c-typeck.c revision 259406
1/* Build expressions with type checking for C compiler. 2 Copyright (C) 1987, 1988, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 3 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006 4 Free Software Foundation, Inc. 5 6This file is part of GCC. 7 8GCC is free software; you can redistribute it and/or modify it under 9the terms of the GNU General Public License as published by the Free 10Software Foundation; either version 2, or (at your option) any later 11version. 12 13GCC is distributed in the hope that it will be useful, but WITHOUT ANY 14WARRANTY; without even the implied warranty of MERCHANTABILITY or 15FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 16for more details. 17 18You should have received a copy of the GNU General Public License 19along with GCC; see the file COPYING. If not, write to the Free 20Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 2102110-1301, USA. */ 22 23 24/* This file is part of the C front end. 25 It contains routines to build C expressions given their operands, 26 including computing the types of the result, C-specific error checks, 27 and some optimization. */ 28 29#include "config.h" 30#include "system.h" 31#include "coretypes.h" 32#include "tm.h" 33#include "rtl.h" 34#include "tree.h" 35#include "langhooks.h" 36#include "c-tree.h" 37#include "tm_p.h" 38#include "flags.h" 39#include "output.h" 40#include "expr.h" 41#include "toplev.h" 42#include "intl.h" 43#include "ggc.h" 44#include "target.h" 45#include "tree-iterator.h" 46#include "tree-gimple.h" 47#include "tree-flow.h" 48 49/* Possible cases of implicit bad conversions. Used to select 50 diagnostic messages in convert_for_assignment. */ 51enum impl_conv { 52 ic_argpass, 53 ic_argpass_nonproto, 54 ic_assign, 55 ic_init, 56 ic_return 57}; 58 59/* The level of nesting inside "__alignof__". */ 60int in_alignof; 61 62/* The level of nesting inside "sizeof". */ 63int in_sizeof; 64 65/* The level of nesting inside "typeof". */ 66int in_typeof; 67 68struct c_label_context_se *label_context_stack_se; 69struct c_label_context_vm *label_context_stack_vm; 70 71/* Nonzero if we've already printed a "missing braces around initializer" 72 message within this initializer. */ 73static int missing_braces_mentioned; 74 75static int require_constant_value; 76static int require_constant_elements; 77 78static bool null_pointer_constant_p (tree); 79static tree qualify_type (tree, tree); 80static int tagged_types_tu_compatible_p (tree, tree); 81static int comp_target_types (tree, tree); 82static int function_types_compatible_p (tree, tree); 83static int type_lists_compatible_p (tree, tree); 84static tree decl_constant_value_for_broken_optimization (tree); 85static tree lookup_field (tree, tree); 86static tree convert_arguments (tree, tree, tree, tree); 87static tree pointer_diff (tree, tree); 88static tree convert_for_assignment (tree, tree, enum impl_conv, tree, tree, 89 int); 90static tree valid_compound_expr_initializer (tree, tree); 91static void push_string (const char *); 92static void push_member_name (tree); 93static int spelling_length (void); 94static char *print_spelling (char *); 95static void warning_init (const char *); 96static tree digest_init (tree, tree, bool, int); 97static void output_init_element (tree, bool, tree, tree, int); 98static void output_pending_init_elements (int); 99static int set_designator (int); 100static void push_range_stack (tree); 101static void add_pending_init (tree, tree); 102static void set_nonincremental_init (void); 103static void set_nonincremental_init_from_string (tree); 104static tree find_init_member (tree); 105static void readonly_error (tree, enum lvalue_use); 106static int lvalue_or_else (tree, enum lvalue_use); 107static int lvalue_p (tree); 108static void record_maybe_used_decl (tree); 109static int comptypes_internal (tree, tree); 110 111/* Return true if EXP is a null pointer constant, false otherwise. */ 112 113static bool 114null_pointer_constant_p (tree expr) 115{ 116 /* This should really operate on c_expr structures, but they aren't 117 yet available everywhere required. */ 118 tree type = TREE_TYPE (expr); 119 return (TREE_CODE (expr) == INTEGER_CST 120 && !TREE_CONSTANT_OVERFLOW (expr) 121 && integer_zerop (expr) 122 && (INTEGRAL_TYPE_P (type) 123 || (TREE_CODE (type) == POINTER_TYPE 124 && VOID_TYPE_P (TREE_TYPE (type)) 125 && TYPE_QUALS (TREE_TYPE (type)) == TYPE_UNQUALIFIED))); 126} 127/* This is a cache to hold if two types are compatible or not. */ 128 129struct tagged_tu_seen_cache { 130 const struct tagged_tu_seen_cache * next; 131 tree t1; 132 tree t2; 133 /* The return value of tagged_types_tu_compatible_p if we had seen 134 these two types already. */ 135 int val; 136}; 137 138static const struct tagged_tu_seen_cache * tagged_tu_seen_base; 139static void free_all_tagged_tu_seen_up_to (const struct tagged_tu_seen_cache *); 140 141/* Do `exp = require_complete_type (exp);' to make sure exp 142 does not have an incomplete type. (That includes void types.) */ 143 144tree 145require_complete_type (tree value) 146{ 147 tree type = TREE_TYPE (value); 148 149 if (value == error_mark_node || type == error_mark_node) 150 return error_mark_node; 151 152 /* First, detect a valid value with a complete type. */ 153 if (COMPLETE_TYPE_P (type)) 154 return value; 155 156 c_incomplete_type_error (value, type); 157 return error_mark_node; 158} 159 160/* Print an error message for invalid use of an incomplete type. 161 VALUE is the expression that was used (or 0 if that isn't known) 162 and TYPE is the type that was invalid. */ 163 164void 165c_incomplete_type_error (tree value, tree type) 166{ 167 const char *type_code_string; 168 169 /* Avoid duplicate error message. */ 170 if (TREE_CODE (type) == ERROR_MARK) 171 return; 172 173 if (value != 0 && (TREE_CODE (value) == VAR_DECL 174 || TREE_CODE (value) == PARM_DECL)) 175 error ("%qD has an incomplete type", value); 176 else 177 { 178 retry: 179 /* We must print an error message. Be clever about what it says. */ 180 181 switch (TREE_CODE (type)) 182 { 183 case RECORD_TYPE: 184 type_code_string = "struct"; 185 break; 186 187 case UNION_TYPE: 188 type_code_string = "union"; 189 break; 190 191 case ENUMERAL_TYPE: 192 type_code_string = "enum"; 193 break; 194 195 case VOID_TYPE: 196 error ("invalid use of void expression"); 197 return; 198 199 case ARRAY_TYPE: 200 if (TYPE_DOMAIN (type)) 201 { 202 if (TYPE_MAX_VALUE (TYPE_DOMAIN (type)) == NULL) 203 { 204 error ("invalid use of flexible array member"); 205 return; 206 } 207 type = TREE_TYPE (type); 208 goto retry; 209 } 210 error ("invalid use of array with unspecified bounds"); 211 return; 212 213 default: 214 gcc_unreachable (); 215 } 216 217 if (TREE_CODE (TYPE_NAME (type)) == IDENTIFIER_NODE) 218 error ("invalid use of undefined type %<%s %E%>", 219 type_code_string, TYPE_NAME (type)); 220 else 221 /* If this type has a typedef-name, the TYPE_NAME is a TYPE_DECL. */ 222 error ("invalid use of incomplete typedef %qD", TYPE_NAME (type)); 223 } 224} 225 226/* Given a type, apply default promotions wrt unnamed function 227 arguments and return the new type. */ 228 229tree 230c_type_promotes_to (tree type) 231{ 232 if (TYPE_MAIN_VARIANT (type) == float_type_node) 233 return double_type_node; 234 235 if (c_promoting_integer_type_p (type)) 236 { 237 /* Preserve unsignedness if not really getting any wider. */ 238 if (TYPE_UNSIGNED (type) 239 && (TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node))) 240 return unsigned_type_node; 241 return integer_type_node; 242 } 243 244 return type; 245} 246 247/* Return a variant of TYPE which has all the type qualifiers of LIKE 248 as well as those of TYPE. */ 249 250static tree 251qualify_type (tree type, tree like) 252{ 253 return c_build_qualified_type (type, 254 TYPE_QUALS (type) | TYPE_QUALS (like)); 255} 256 257/* Return true iff the given tree T is a variable length array. */ 258 259bool 260c_vla_type_p (tree t) 261{ 262 if (TREE_CODE (t) == ARRAY_TYPE 263 && C_TYPE_VARIABLE_SIZE (t)) 264 return true; 265 return false; 266} 267 268/* Return the composite type of two compatible types. 269 270 We assume that comptypes has already been done and returned 271 nonzero; if that isn't so, this may crash. In particular, we 272 assume that qualifiers match. */ 273 274tree 275composite_type (tree t1, tree t2) 276{ 277 enum tree_code code1; 278 enum tree_code code2; 279 tree attributes; 280 281 /* Save time if the two types are the same. */ 282 283 if (t1 == t2) return t1; 284 285 /* If one type is nonsense, use the other. */ 286 if (t1 == error_mark_node) 287 return t2; 288 if (t2 == error_mark_node) 289 return t1; 290 291 code1 = TREE_CODE (t1); 292 code2 = TREE_CODE (t2); 293 294 /* Merge the attributes. */ 295 attributes = targetm.merge_type_attributes (t1, t2); 296 297 /* If one is an enumerated type and the other is the compatible 298 integer type, the composite type might be either of the two 299 (DR#013 question 3). For consistency, use the enumerated type as 300 the composite type. */ 301 302 if (code1 == ENUMERAL_TYPE && code2 == INTEGER_TYPE) 303 return t1; 304 if (code2 == ENUMERAL_TYPE && code1 == INTEGER_TYPE) 305 return t2; 306 307 gcc_assert (code1 == code2); 308 309 switch (code1) 310 { 311 case POINTER_TYPE: 312 /* For two pointers, do this recursively on the target type. */ 313 { 314 tree pointed_to_1 = TREE_TYPE (t1); 315 tree pointed_to_2 = TREE_TYPE (t2); 316 tree target = composite_type (pointed_to_1, pointed_to_2); 317 t1 = build_pointer_type (target); 318 t1 = build_type_attribute_variant (t1, attributes); 319 return qualify_type (t1, t2); 320 } 321 322 case ARRAY_TYPE: 323 { 324 tree elt = composite_type (TREE_TYPE (t1), TREE_TYPE (t2)); 325 int quals; 326 tree unqual_elt; 327 tree d1 = TYPE_DOMAIN (t1); 328 tree d2 = TYPE_DOMAIN (t2); 329 bool d1_variable, d2_variable; 330 bool d1_zero, d2_zero; 331 332 /* We should not have any type quals on arrays at all. */ 333 gcc_assert (!TYPE_QUALS (t1) && !TYPE_QUALS (t2)); 334 335 d1_zero = d1 == 0 || !TYPE_MAX_VALUE (d1); 336 d2_zero = d2 == 0 || !TYPE_MAX_VALUE (d2); 337 338 d1_variable = (!d1_zero 339 && (TREE_CODE (TYPE_MIN_VALUE (d1)) != INTEGER_CST 340 || TREE_CODE (TYPE_MAX_VALUE (d1)) != INTEGER_CST)); 341 d2_variable = (!d2_zero 342 && (TREE_CODE (TYPE_MIN_VALUE (d2)) != INTEGER_CST 343 || TREE_CODE (TYPE_MAX_VALUE (d2)) != INTEGER_CST)); 344 d1_variable = d1_variable || (d1_zero && c_vla_type_p (t1)); 345 d2_variable = d2_variable || (d2_zero && c_vla_type_p (t2)); 346 347 /* Save space: see if the result is identical to one of the args. */ 348 if (elt == TREE_TYPE (t1) && TYPE_DOMAIN (t1) 349 && (d2_variable || d2_zero || !d1_variable)) 350 return build_type_attribute_variant (t1, attributes); 351 if (elt == TREE_TYPE (t2) && TYPE_DOMAIN (t2) 352 && (d1_variable || d1_zero || !d2_variable)) 353 return build_type_attribute_variant (t2, attributes); 354 355 if (elt == TREE_TYPE (t1) && !TYPE_DOMAIN (t2) && !TYPE_DOMAIN (t1)) 356 return build_type_attribute_variant (t1, attributes); 357 if (elt == TREE_TYPE (t2) && !TYPE_DOMAIN (t2) && !TYPE_DOMAIN (t1)) 358 return build_type_attribute_variant (t2, attributes); 359 360 /* Merge the element types, and have a size if either arg has 361 one. We may have qualifiers on the element types. To set 362 up TYPE_MAIN_VARIANT correctly, we need to form the 363 composite of the unqualified types and add the qualifiers 364 back at the end. */ 365 quals = TYPE_QUALS (strip_array_types (elt)); 366 unqual_elt = c_build_qualified_type (elt, TYPE_UNQUALIFIED); 367 t1 = build_array_type (unqual_elt, 368 TYPE_DOMAIN ((TYPE_DOMAIN (t1) 369 && (d2_variable 370 || d2_zero 371 || !d1_variable)) 372 ? t1 373 : t2)); 374 t1 = c_build_qualified_type (t1, quals); 375 return build_type_attribute_variant (t1, attributes); 376 } 377 378 case ENUMERAL_TYPE: 379 case RECORD_TYPE: 380 case UNION_TYPE: 381 if (attributes != NULL) 382 { 383 /* Try harder not to create a new aggregate type. */ 384 if (attribute_list_equal (TYPE_ATTRIBUTES (t1), attributes)) 385 return t1; 386 if (attribute_list_equal (TYPE_ATTRIBUTES (t2), attributes)) 387 return t2; 388 } 389 return build_type_attribute_variant (t1, attributes); 390 391 case FUNCTION_TYPE: 392 /* Function types: prefer the one that specified arg types. 393 If both do, merge the arg types. Also merge the return types. */ 394 { 395 tree valtype = composite_type (TREE_TYPE (t1), TREE_TYPE (t2)); 396 tree p1 = TYPE_ARG_TYPES (t1); 397 tree p2 = TYPE_ARG_TYPES (t2); 398 int len; 399 tree newargs, n; 400 int i; 401 402 /* Save space: see if the result is identical to one of the args. */ 403 if (valtype == TREE_TYPE (t1) && !TYPE_ARG_TYPES (t2)) 404 return build_type_attribute_variant (t1, attributes); 405 if (valtype == TREE_TYPE (t2) && !TYPE_ARG_TYPES (t1)) 406 return build_type_attribute_variant (t2, attributes); 407 408 /* Simple way if one arg fails to specify argument types. */ 409 if (TYPE_ARG_TYPES (t1) == 0) 410 { 411 t1 = build_function_type (valtype, TYPE_ARG_TYPES (t2)); 412 t1 = build_type_attribute_variant (t1, attributes); 413 return qualify_type (t1, t2); 414 } 415 if (TYPE_ARG_TYPES (t2) == 0) 416 { 417 t1 = build_function_type (valtype, TYPE_ARG_TYPES (t1)); 418 t1 = build_type_attribute_variant (t1, attributes); 419 return qualify_type (t1, t2); 420 } 421 422 /* If both args specify argument types, we must merge the two 423 lists, argument by argument. */ 424 /* Tell global_bindings_p to return false so that variable_size 425 doesn't die on VLAs in parameter types. */ 426 c_override_global_bindings_to_false = true; 427 428 len = list_length (p1); 429 newargs = 0; 430 431 for (i = 0; i < len; i++) 432 newargs = tree_cons (NULL_TREE, NULL_TREE, newargs); 433 434 n = newargs; 435 436 for (; p1; 437 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2), n = TREE_CHAIN (n)) 438 { 439 /* A null type means arg type is not specified. 440 Take whatever the other function type has. */ 441 if (TREE_VALUE (p1) == 0) 442 { 443 TREE_VALUE (n) = TREE_VALUE (p2); 444 goto parm_done; 445 } 446 if (TREE_VALUE (p2) == 0) 447 { 448 TREE_VALUE (n) = TREE_VALUE (p1); 449 goto parm_done; 450 } 451 452 /* Given wait (union {union wait *u; int *i} *) 453 and wait (union wait *), 454 prefer union wait * as type of parm. */ 455 if (TREE_CODE (TREE_VALUE (p1)) == UNION_TYPE 456 && TREE_VALUE (p1) != TREE_VALUE (p2)) 457 { 458 tree memb; 459 tree mv2 = TREE_VALUE (p2); 460 if (mv2 && mv2 != error_mark_node 461 && TREE_CODE (mv2) != ARRAY_TYPE) 462 mv2 = TYPE_MAIN_VARIANT (mv2); 463 for (memb = TYPE_FIELDS (TREE_VALUE (p1)); 464 memb; memb = TREE_CHAIN (memb)) 465 { 466 tree mv3 = TREE_TYPE (memb); 467 if (mv3 && mv3 != error_mark_node 468 && TREE_CODE (mv3) != ARRAY_TYPE) 469 mv3 = TYPE_MAIN_VARIANT (mv3); 470 if (comptypes (mv3, mv2)) 471 { 472 TREE_VALUE (n) = composite_type (TREE_TYPE (memb), 473 TREE_VALUE (p2)); 474 if (pedantic) 475 pedwarn ("function types not truly compatible in ISO C"); 476 goto parm_done; 477 } 478 } 479 } 480 if (TREE_CODE (TREE_VALUE (p2)) == UNION_TYPE 481 && TREE_VALUE (p2) != TREE_VALUE (p1)) 482 { 483 tree memb; 484 tree mv1 = TREE_VALUE (p1); 485 if (mv1 && mv1 != error_mark_node 486 && TREE_CODE (mv1) != ARRAY_TYPE) 487 mv1 = TYPE_MAIN_VARIANT (mv1); 488 for (memb = TYPE_FIELDS (TREE_VALUE (p2)); 489 memb; memb = TREE_CHAIN (memb)) 490 { 491 tree mv3 = TREE_TYPE (memb); 492 if (mv3 && mv3 != error_mark_node 493 && TREE_CODE (mv3) != ARRAY_TYPE) 494 mv3 = TYPE_MAIN_VARIANT (mv3); 495 if (comptypes (mv3, mv1)) 496 { 497 TREE_VALUE (n) = composite_type (TREE_TYPE (memb), 498 TREE_VALUE (p1)); 499 if (pedantic) 500 pedwarn ("function types not truly compatible in ISO C"); 501 goto parm_done; 502 } 503 } 504 } 505 TREE_VALUE (n) = composite_type (TREE_VALUE (p1), TREE_VALUE (p2)); 506 parm_done: ; 507 } 508 509 c_override_global_bindings_to_false = false; 510 t1 = build_function_type (valtype, newargs); 511 t1 = qualify_type (t1, t2); 512 /* ... falls through ... */ 513 } 514 515 default: 516 return build_type_attribute_variant (t1, attributes); 517 } 518 519} 520 521/* Return the type of a conditional expression between pointers to 522 possibly differently qualified versions of compatible types. 523 524 We assume that comp_target_types has already been done and returned 525 nonzero; if that isn't so, this may crash. */ 526 527static tree 528common_pointer_type (tree t1, tree t2) 529{ 530 tree attributes; 531 tree pointed_to_1, mv1; 532 tree pointed_to_2, mv2; 533 tree target; 534 535 /* Save time if the two types are the same. */ 536 537 if (t1 == t2) return t1; 538 539 /* If one type is nonsense, use the other. */ 540 if (t1 == error_mark_node) 541 return t2; 542 if (t2 == error_mark_node) 543 return t1; 544 545 gcc_assert (TREE_CODE (t1) == POINTER_TYPE 546 && TREE_CODE (t2) == POINTER_TYPE); 547 548 /* Merge the attributes. */ 549 attributes = targetm.merge_type_attributes (t1, t2); 550 551 /* Find the composite type of the target types, and combine the 552 qualifiers of the two types' targets. Do not lose qualifiers on 553 array element types by taking the TYPE_MAIN_VARIANT. */ 554 mv1 = pointed_to_1 = TREE_TYPE (t1); 555 mv2 = pointed_to_2 = TREE_TYPE (t2); 556 if (TREE_CODE (mv1) != ARRAY_TYPE) 557 mv1 = TYPE_MAIN_VARIANT (pointed_to_1); 558 if (TREE_CODE (mv2) != ARRAY_TYPE) 559 mv2 = TYPE_MAIN_VARIANT (pointed_to_2); 560 target = composite_type (mv1, mv2); 561 t1 = build_pointer_type (c_build_qualified_type 562 (target, 563 TYPE_QUALS (pointed_to_1) | 564 TYPE_QUALS (pointed_to_2))); 565 return build_type_attribute_variant (t1, attributes); 566} 567 568/* Return the common type for two arithmetic types under the usual 569 arithmetic conversions. The default conversions have already been 570 applied, and enumerated types converted to their compatible integer 571 types. The resulting type is unqualified and has no attributes. 572 573 This is the type for the result of most arithmetic operations 574 if the operands have the given two types. */ 575 576static tree 577c_common_type (tree t1, tree t2) 578{ 579 enum tree_code code1; 580 enum tree_code code2; 581 582 /* If one type is nonsense, use the other. */ 583 if (t1 == error_mark_node) 584 return t2; 585 if (t2 == error_mark_node) 586 return t1; 587 588 if (TYPE_QUALS (t1) != TYPE_UNQUALIFIED) 589 t1 = TYPE_MAIN_VARIANT (t1); 590 591 if (TYPE_QUALS (t2) != TYPE_UNQUALIFIED) 592 t2 = TYPE_MAIN_VARIANT (t2); 593 594 if (TYPE_ATTRIBUTES (t1) != NULL_TREE) 595 t1 = build_type_attribute_variant (t1, NULL_TREE); 596 597 if (TYPE_ATTRIBUTES (t2) != NULL_TREE) 598 t2 = build_type_attribute_variant (t2, NULL_TREE); 599 600 /* Save time if the two types are the same. */ 601 602 if (t1 == t2) return t1; 603 604 code1 = TREE_CODE (t1); 605 code2 = TREE_CODE (t2); 606 607 gcc_assert (code1 == VECTOR_TYPE || code1 == COMPLEX_TYPE 608 || code1 == REAL_TYPE || code1 == INTEGER_TYPE); 609 gcc_assert (code2 == VECTOR_TYPE || code2 == COMPLEX_TYPE 610 || code2 == REAL_TYPE || code2 == INTEGER_TYPE); 611 612 /* When one operand is a decimal float type, the other operand cannot be 613 a generic float type or a complex type. We also disallow vector types 614 here. */ 615 if ((DECIMAL_FLOAT_TYPE_P (t1) || DECIMAL_FLOAT_TYPE_P (t2)) 616 && !(DECIMAL_FLOAT_TYPE_P (t1) && DECIMAL_FLOAT_TYPE_P (t2))) 617 { 618 if (code1 == VECTOR_TYPE || code2 == VECTOR_TYPE) 619 { 620 error ("can%'t mix operands of decimal float and vector types"); 621 return error_mark_node; 622 } 623 if (code1 == COMPLEX_TYPE || code2 == COMPLEX_TYPE) 624 { 625 error ("can%'t mix operands of decimal float and complex types"); 626 return error_mark_node; 627 } 628 if (code1 == REAL_TYPE && code2 == REAL_TYPE) 629 { 630 error ("can%'t mix operands of decimal float and other float types"); 631 return error_mark_node; 632 } 633 } 634 635 /* If one type is a vector type, return that type. (How the usual 636 arithmetic conversions apply to the vector types extension is not 637 precisely specified.) */ 638 if (code1 == VECTOR_TYPE) 639 return t1; 640 641 if (code2 == VECTOR_TYPE) 642 return t2; 643 644 /* If one type is complex, form the common type of the non-complex 645 components, then make that complex. Use T1 or T2 if it is the 646 required type. */ 647 if (code1 == COMPLEX_TYPE || code2 == COMPLEX_TYPE) 648 { 649 tree subtype1 = code1 == COMPLEX_TYPE ? TREE_TYPE (t1) : t1; 650 tree subtype2 = code2 == COMPLEX_TYPE ? TREE_TYPE (t2) : t2; 651 tree subtype = c_common_type (subtype1, subtype2); 652 653 if (code1 == COMPLEX_TYPE && TREE_TYPE (t1) == subtype) 654 return t1; 655 else if (code2 == COMPLEX_TYPE && TREE_TYPE (t2) == subtype) 656 return t2; 657 else 658 return build_complex_type (subtype); 659 } 660 661 /* If only one is real, use it as the result. */ 662 663 if (code1 == REAL_TYPE && code2 != REAL_TYPE) 664 return t1; 665 666 if (code2 == REAL_TYPE && code1 != REAL_TYPE) 667 return t2; 668 669 /* If both are real and either are decimal floating point types, use 670 the decimal floating point type with the greater precision. */ 671 672 if (code1 == REAL_TYPE && code2 == REAL_TYPE) 673 { 674 if (TYPE_MAIN_VARIANT (t1) == dfloat128_type_node 675 || TYPE_MAIN_VARIANT (t2) == dfloat128_type_node) 676 return dfloat128_type_node; 677 else if (TYPE_MAIN_VARIANT (t1) == dfloat64_type_node 678 || TYPE_MAIN_VARIANT (t2) == dfloat64_type_node) 679 return dfloat64_type_node; 680 else if (TYPE_MAIN_VARIANT (t1) == dfloat32_type_node 681 || TYPE_MAIN_VARIANT (t2) == dfloat32_type_node) 682 return dfloat32_type_node; 683 } 684 685 /* Both real or both integers; use the one with greater precision. */ 686 687 if (TYPE_PRECISION (t1) > TYPE_PRECISION (t2)) 688 return t1; 689 else if (TYPE_PRECISION (t2) > TYPE_PRECISION (t1)) 690 return t2; 691 692 /* Same precision. Prefer long longs to longs to ints when the 693 same precision, following the C99 rules on integer type rank 694 (which are equivalent to the C90 rules for C90 types). */ 695 696 if (TYPE_MAIN_VARIANT (t1) == long_long_unsigned_type_node 697 || TYPE_MAIN_VARIANT (t2) == long_long_unsigned_type_node) 698 return long_long_unsigned_type_node; 699 700 if (TYPE_MAIN_VARIANT (t1) == long_long_integer_type_node 701 || TYPE_MAIN_VARIANT (t2) == long_long_integer_type_node) 702 { 703 if (TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2)) 704 return long_long_unsigned_type_node; 705 else 706 return long_long_integer_type_node; 707 } 708 709 if (TYPE_MAIN_VARIANT (t1) == long_unsigned_type_node 710 || TYPE_MAIN_VARIANT (t2) == long_unsigned_type_node) 711 return long_unsigned_type_node; 712 713 if (TYPE_MAIN_VARIANT (t1) == long_integer_type_node 714 || TYPE_MAIN_VARIANT (t2) == long_integer_type_node) 715 { 716 /* But preserve unsignedness from the other type, 717 since long cannot hold all the values of an unsigned int. */ 718 if (TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2)) 719 return long_unsigned_type_node; 720 else 721 return long_integer_type_node; 722 } 723 724 /* Likewise, prefer long double to double even if same size. */ 725 if (TYPE_MAIN_VARIANT (t1) == long_double_type_node 726 || TYPE_MAIN_VARIANT (t2) == long_double_type_node) 727 return long_double_type_node; 728 729 /* Otherwise prefer the unsigned one. */ 730 731 if (TYPE_UNSIGNED (t1)) 732 return t1; 733 else 734 return t2; 735} 736 737/* Wrapper around c_common_type that is used by c-common.c and other 738 front end optimizations that remove promotions. ENUMERAL_TYPEs 739 are allowed here and are converted to their compatible integer types. 740 BOOLEAN_TYPEs are allowed here and return either boolean_type_node or 741 preferably a non-Boolean type as the common type. */ 742tree 743common_type (tree t1, tree t2) 744{ 745 if (TREE_CODE (t1) == ENUMERAL_TYPE) 746 t1 = c_common_type_for_size (TYPE_PRECISION (t1), 1); 747 if (TREE_CODE (t2) == ENUMERAL_TYPE) 748 t2 = c_common_type_for_size (TYPE_PRECISION (t2), 1); 749 750 /* If both types are BOOLEAN_TYPE, then return boolean_type_node. */ 751 if (TREE_CODE (t1) == BOOLEAN_TYPE 752 && TREE_CODE (t2) == BOOLEAN_TYPE) 753 return boolean_type_node; 754 755 /* If either type is BOOLEAN_TYPE, then return the other. */ 756 if (TREE_CODE (t1) == BOOLEAN_TYPE) 757 return t2; 758 if (TREE_CODE (t2) == BOOLEAN_TYPE) 759 return t1; 760 761 return c_common_type (t1, t2); 762} 763 764/* Return 1 if TYPE1 and TYPE2 are compatible types for assignment 765 or various other operations. Return 2 if they are compatible 766 but a warning may be needed if you use them together. */ 767 768int 769comptypes (tree type1, tree type2) 770{ 771 const struct tagged_tu_seen_cache * tagged_tu_seen_base1 = tagged_tu_seen_base; 772 int val; 773 774 val = comptypes_internal (type1, type2); 775 free_all_tagged_tu_seen_up_to (tagged_tu_seen_base1); 776 777 return val; 778} 779 780/* Return 1 if TYPE1 and TYPE2 are compatible types for assignment 781 or various other operations. Return 2 if they are compatible 782 but a warning may be needed if you use them together. This 783 differs from comptypes, in that we don't free the seen types. */ 784 785static int 786comptypes_internal (tree type1, tree type2) 787{ 788 tree t1 = type1; 789 tree t2 = type2; 790 int attrval, val; 791 792 /* Suppress errors caused by previously reported errors. */ 793 794 if (t1 == t2 || !t1 || !t2 795 || TREE_CODE (t1) == ERROR_MARK || TREE_CODE (t2) == ERROR_MARK) 796 return 1; 797 798 /* If either type is the internal version of sizetype, return the 799 language version. */ 800 if (TREE_CODE (t1) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t1) 801 && TYPE_ORIG_SIZE_TYPE (t1)) 802 t1 = TYPE_ORIG_SIZE_TYPE (t1); 803 804 if (TREE_CODE (t2) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t2) 805 && TYPE_ORIG_SIZE_TYPE (t2)) 806 t2 = TYPE_ORIG_SIZE_TYPE (t2); 807 808 809 /* Enumerated types are compatible with integer types, but this is 810 not transitive: two enumerated types in the same translation unit 811 are compatible with each other only if they are the same type. */ 812 813 if (TREE_CODE (t1) == ENUMERAL_TYPE && TREE_CODE (t2) != ENUMERAL_TYPE) 814 t1 = c_common_type_for_size (TYPE_PRECISION (t1), TYPE_UNSIGNED (t1)); 815 else if (TREE_CODE (t2) == ENUMERAL_TYPE && TREE_CODE (t1) != ENUMERAL_TYPE) 816 t2 = c_common_type_for_size (TYPE_PRECISION (t2), TYPE_UNSIGNED (t2)); 817 818 if (t1 == t2) 819 return 1; 820 821 /* Different classes of types can't be compatible. */ 822 823 if (TREE_CODE (t1) != TREE_CODE (t2)) 824 return 0; 825 826 /* Qualifiers must match. C99 6.7.3p9 */ 827 828 if (TYPE_QUALS (t1) != TYPE_QUALS (t2)) 829 return 0; 830 831 /* Allow for two different type nodes which have essentially the same 832 definition. Note that we already checked for equality of the type 833 qualifiers (just above). */ 834 835 if (TREE_CODE (t1) != ARRAY_TYPE 836 && TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2)) 837 return 1; 838 839 /* 1 if no need for warning yet, 2 if warning cause has been seen. */ 840 if (!(attrval = targetm.comp_type_attributes (t1, t2))) 841 return 0; 842 843 /* 1 if no need for warning yet, 2 if warning cause has been seen. */ 844 val = 0; 845 846 switch (TREE_CODE (t1)) 847 { 848 case POINTER_TYPE: 849 /* Do not remove mode or aliasing information. */ 850 if (TYPE_MODE (t1) != TYPE_MODE (t2) 851 || TYPE_REF_CAN_ALIAS_ALL (t1) != TYPE_REF_CAN_ALIAS_ALL (t2)) 852 break; 853 val = (TREE_TYPE (t1) == TREE_TYPE (t2) 854 ? 1 : comptypes_internal (TREE_TYPE (t1), TREE_TYPE (t2))); 855 break; 856 857 case FUNCTION_TYPE: 858 val = function_types_compatible_p (t1, t2); 859 break; 860 861 case ARRAY_TYPE: 862 { 863 tree d1 = TYPE_DOMAIN (t1); 864 tree d2 = TYPE_DOMAIN (t2); 865 bool d1_variable, d2_variable; 866 bool d1_zero, d2_zero; 867 val = 1; 868 869 /* Target types must match incl. qualifiers. */ 870 if (TREE_TYPE (t1) != TREE_TYPE (t2) 871 && 0 == (val = comptypes_internal (TREE_TYPE (t1), TREE_TYPE (t2)))) 872 return 0; 873 874 /* Sizes must match unless one is missing or variable. */ 875 if (d1 == 0 || d2 == 0 || d1 == d2) 876 break; 877 878 d1_zero = !TYPE_MAX_VALUE (d1); 879 d2_zero = !TYPE_MAX_VALUE (d2); 880 881 d1_variable = (!d1_zero 882 && (TREE_CODE (TYPE_MIN_VALUE (d1)) != INTEGER_CST 883 || TREE_CODE (TYPE_MAX_VALUE (d1)) != INTEGER_CST)); 884 d2_variable = (!d2_zero 885 && (TREE_CODE (TYPE_MIN_VALUE (d2)) != INTEGER_CST 886 || TREE_CODE (TYPE_MAX_VALUE (d2)) != INTEGER_CST)); 887 d1_variable = d1_variable || (d1_zero && c_vla_type_p (t1)); 888 d2_variable = d2_variable || (d2_zero && c_vla_type_p (t2)); 889 890 if (d1_variable || d2_variable) 891 break; 892 if (d1_zero && d2_zero) 893 break; 894 if (d1_zero || d2_zero 895 || !tree_int_cst_equal (TYPE_MIN_VALUE (d1), TYPE_MIN_VALUE (d2)) 896 || !tree_int_cst_equal (TYPE_MAX_VALUE (d1), TYPE_MAX_VALUE (d2))) 897 val = 0; 898 899 break; 900 } 901 902 case ENUMERAL_TYPE: 903 case RECORD_TYPE: 904 case UNION_TYPE: 905 if (val != 1 && !same_translation_unit_p (t1, t2)) 906 { 907 tree a1 = TYPE_ATTRIBUTES (t1); 908 tree a2 = TYPE_ATTRIBUTES (t2); 909 910 if (! attribute_list_contained (a1, a2) 911 && ! attribute_list_contained (a2, a1)) 912 break; 913 914 if (attrval != 2) 915 return tagged_types_tu_compatible_p (t1, t2); 916 val = tagged_types_tu_compatible_p (t1, t2); 917 } 918 break; 919 920 case VECTOR_TYPE: 921 val = TYPE_VECTOR_SUBPARTS (t1) == TYPE_VECTOR_SUBPARTS (t2) 922 && comptypes_internal (TREE_TYPE (t1), TREE_TYPE (t2)); 923 break; 924 925 default: 926 break; 927 } 928 return attrval == 2 && val == 1 ? 2 : val; 929} 930 931/* Return 1 if TTL and TTR are pointers to types that are equivalent, 932 ignoring their qualifiers. */ 933 934static int 935comp_target_types (tree ttl, tree ttr) 936{ 937 int val; 938 tree mvl, mvr; 939 940 /* Do not lose qualifiers on element types of array types that are 941 pointer targets by taking their TYPE_MAIN_VARIANT. */ 942 mvl = TREE_TYPE (ttl); 943 mvr = TREE_TYPE (ttr); 944 if (TREE_CODE (mvl) != ARRAY_TYPE) 945 mvl = TYPE_MAIN_VARIANT (mvl); 946 if (TREE_CODE (mvr) != ARRAY_TYPE) 947 mvr = TYPE_MAIN_VARIANT (mvr); 948 val = comptypes (mvl, mvr); 949 950 if (val == 2 && pedantic) 951 pedwarn ("types are not quite compatible"); 952 return val; 953} 954 955/* Subroutines of `comptypes'. */ 956 957/* Determine whether two trees derive from the same translation unit. 958 If the CONTEXT chain ends in a null, that tree's context is still 959 being parsed, so if two trees have context chains ending in null, 960 they're in the same translation unit. */ 961int 962same_translation_unit_p (tree t1, tree t2) 963{ 964 while (t1 && TREE_CODE (t1) != TRANSLATION_UNIT_DECL) 965 switch (TREE_CODE_CLASS (TREE_CODE (t1))) 966 { 967 case tcc_declaration: 968 t1 = DECL_CONTEXT (t1); break; 969 case tcc_type: 970 t1 = TYPE_CONTEXT (t1); break; 971 case tcc_exceptional: 972 t1 = BLOCK_SUPERCONTEXT (t1); break; /* assume block */ 973 default: gcc_unreachable (); 974 } 975 976 while (t2 && TREE_CODE (t2) != TRANSLATION_UNIT_DECL) 977 switch (TREE_CODE_CLASS (TREE_CODE (t2))) 978 { 979 case tcc_declaration: 980 t2 = DECL_CONTEXT (t2); break; 981 case tcc_type: 982 t2 = TYPE_CONTEXT (t2); break; 983 case tcc_exceptional: 984 t2 = BLOCK_SUPERCONTEXT (t2); break; /* assume block */ 985 default: gcc_unreachable (); 986 } 987 988 return t1 == t2; 989} 990 991/* Allocate the seen two types, assuming that they are compatible. */ 992 993static struct tagged_tu_seen_cache * 994alloc_tagged_tu_seen_cache (tree t1, tree t2) 995{ 996 struct tagged_tu_seen_cache *tu = XNEW (struct tagged_tu_seen_cache); 997 tu->next = tagged_tu_seen_base; 998 tu->t1 = t1; 999 tu->t2 = t2; 1000 1001 tagged_tu_seen_base = tu; 1002 1003 /* The C standard says that two structures in different translation 1004 units are compatible with each other only if the types of their 1005 fields are compatible (among other things). We assume that they 1006 are compatible until proven otherwise when building the cache. 1007 An example where this can occur is: 1008 struct a 1009 { 1010 struct a *next; 1011 }; 1012 If we are comparing this against a similar struct in another TU, 1013 and did not assume they were compatible, we end up with an infinite 1014 loop. */ 1015 tu->val = 1; 1016 return tu; 1017} 1018 1019/* Free the seen types until we get to TU_TIL. */ 1020 1021static void 1022free_all_tagged_tu_seen_up_to (const struct tagged_tu_seen_cache *tu_til) 1023{ 1024 const struct tagged_tu_seen_cache *tu = tagged_tu_seen_base; 1025 while (tu != tu_til) 1026 { 1027 struct tagged_tu_seen_cache *tu1 = (struct tagged_tu_seen_cache*)tu; 1028 tu = tu1->next; 1029 free (tu1); 1030 } 1031 tagged_tu_seen_base = tu_til; 1032} 1033 1034/* Return 1 if two 'struct', 'union', or 'enum' types T1 and T2 are 1035 compatible. If the two types are not the same (which has been 1036 checked earlier), this can only happen when multiple translation 1037 units are being compiled. See C99 6.2.7 paragraph 1 for the exact 1038 rules. */ 1039 1040static int 1041tagged_types_tu_compatible_p (tree t1, tree t2) 1042{ 1043 tree s1, s2; 1044 bool needs_warning = false; 1045 1046 /* We have to verify that the tags of the types are the same. This 1047 is harder than it looks because this may be a typedef, so we have 1048 to go look at the original type. It may even be a typedef of a 1049 typedef... 1050 In the case of compiler-created builtin structs the TYPE_DECL 1051 may be a dummy, with no DECL_ORIGINAL_TYPE. Don't fault. */ 1052 while (TYPE_NAME (t1) 1053 && TREE_CODE (TYPE_NAME (t1)) == TYPE_DECL 1054 && DECL_ORIGINAL_TYPE (TYPE_NAME (t1))) 1055 t1 = DECL_ORIGINAL_TYPE (TYPE_NAME (t1)); 1056 1057 while (TYPE_NAME (t2) 1058 && TREE_CODE (TYPE_NAME (t2)) == TYPE_DECL 1059 && DECL_ORIGINAL_TYPE (TYPE_NAME (t2))) 1060 t2 = DECL_ORIGINAL_TYPE (TYPE_NAME (t2)); 1061 1062 /* C90 didn't have the requirement that the two tags be the same. */ 1063 if (flag_isoc99 && TYPE_NAME (t1) != TYPE_NAME (t2)) 1064 return 0; 1065 1066 /* C90 didn't say what happened if one or both of the types were 1067 incomplete; we choose to follow C99 rules here, which is that they 1068 are compatible. */ 1069 if (TYPE_SIZE (t1) == NULL 1070 || TYPE_SIZE (t2) == NULL) 1071 return 1; 1072 1073 { 1074 const struct tagged_tu_seen_cache * tts_i; 1075 for (tts_i = tagged_tu_seen_base; tts_i != NULL; tts_i = tts_i->next) 1076 if (tts_i->t1 == t1 && tts_i->t2 == t2) 1077 return tts_i->val; 1078 } 1079 1080 switch (TREE_CODE (t1)) 1081 { 1082 case ENUMERAL_TYPE: 1083 { 1084 struct tagged_tu_seen_cache *tu = alloc_tagged_tu_seen_cache (t1, t2); 1085 /* Speed up the case where the type values are in the same order. */ 1086 tree tv1 = TYPE_VALUES (t1); 1087 tree tv2 = TYPE_VALUES (t2); 1088 1089 if (tv1 == tv2) 1090 { 1091 return 1; 1092 } 1093 1094 for (;tv1 && tv2; tv1 = TREE_CHAIN (tv1), tv2 = TREE_CHAIN (tv2)) 1095 { 1096 if (TREE_PURPOSE (tv1) != TREE_PURPOSE (tv2)) 1097 break; 1098 if (simple_cst_equal (TREE_VALUE (tv1), TREE_VALUE (tv2)) != 1) 1099 { 1100 tu->val = 0; 1101 return 0; 1102 } 1103 } 1104 1105 if (tv1 == NULL_TREE && tv2 == NULL_TREE) 1106 { 1107 return 1; 1108 } 1109 if (tv1 == NULL_TREE || tv2 == NULL_TREE) 1110 { 1111 tu->val = 0; 1112 return 0; 1113 } 1114 1115 if (list_length (TYPE_VALUES (t1)) != list_length (TYPE_VALUES (t2))) 1116 { 1117 tu->val = 0; 1118 return 0; 1119 } 1120 1121 for (s1 = TYPE_VALUES (t1); s1; s1 = TREE_CHAIN (s1)) 1122 { 1123 s2 = purpose_member (TREE_PURPOSE (s1), TYPE_VALUES (t2)); 1124 if (s2 == NULL 1125 || simple_cst_equal (TREE_VALUE (s1), TREE_VALUE (s2)) != 1) 1126 { 1127 tu->val = 0; 1128 return 0; 1129 } 1130 } 1131 return 1; 1132 } 1133 1134 case UNION_TYPE: 1135 { 1136 struct tagged_tu_seen_cache *tu = alloc_tagged_tu_seen_cache (t1, t2); 1137 if (list_length (TYPE_FIELDS (t1)) != list_length (TYPE_FIELDS (t2))) 1138 { 1139 tu->val = 0; 1140 return 0; 1141 } 1142 1143 /* Speed up the common case where the fields are in the same order. */ 1144 for (s1 = TYPE_FIELDS (t1), s2 = TYPE_FIELDS (t2); s1 && s2; 1145 s1 = TREE_CHAIN (s1), s2 = TREE_CHAIN (s2)) 1146 { 1147 int result; 1148 1149 1150 if (DECL_NAME (s1) == NULL 1151 || DECL_NAME (s1) != DECL_NAME (s2)) 1152 break; 1153 result = comptypes_internal (TREE_TYPE (s1), TREE_TYPE (s2)); 1154 if (result == 0) 1155 { 1156 tu->val = 0; 1157 return 0; 1158 } 1159 if (result == 2) 1160 needs_warning = true; 1161 1162 if (TREE_CODE (s1) == FIELD_DECL 1163 && simple_cst_equal (DECL_FIELD_BIT_OFFSET (s1), 1164 DECL_FIELD_BIT_OFFSET (s2)) != 1) 1165 { 1166 tu->val = 0; 1167 return 0; 1168 } 1169 } 1170 if (!s1 && !s2) 1171 { 1172 tu->val = needs_warning ? 2 : 1; 1173 return tu->val; 1174 } 1175 1176 for (s1 = TYPE_FIELDS (t1); s1; s1 = TREE_CHAIN (s1)) 1177 { 1178 bool ok = false; 1179 1180 if (DECL_NAME (s1) != NULL) 1181 for (s2 = TYPE_FIELDS (t2); s2; s2 = TREE_CHAIN (s2)) 1182 if (DECL_NAME (s1) == DECL_NAME (s2)) 1183 { 1184 int result; 1185 result = comptypes_internal (TREE_TYPE (s1), TREE_TYPE (s2)); 1186 if (result == 0) 1187 { 1188 tu->val = 0; 1189 return 0; 1190 } 1191 if (result == 2) 1192 needs_warning = true; 1193 1194 if (TREE_CODE (s1) == FIELD_DECL 1195 && simple_cst_equal (DECL_FIELD_BIT_OFFSET (s1), 1196 DECL_FIELD_BIT_OFFSET (s2)) != 1) 1197 break; 1198 1199 ok = true; 1200 break; 1201 } 1202 if (!ok) 1203 { 1204 tu->val = 0; 1205 return 0; 1206 } 1207 } 1208 tu->val = needs_warning ? 2 : 10; 1209 return tu->val; 1210 } 1211 1212 case RECORD_TYPE: 1213 { 1214 struct tagged_tu_seen_cache *tu = alloc_tagged_tu_seen_cache (t1, t2); 1215 1216 for (s1 = TYPE_FIELDS (t1), s2 = TYPE_FIELDS (t2); 1217 s1 && s2; 1218 s1 = TREE_CHAIN (s1), s2 = TREE_CHAIN (s2)) 1219 { 1220 int result; 1221 if (TREE_CODE (s1) != TREE_CODE (s2) 1222 || DECL_NAME (s1) != DECL_NAME (s2)) 1223 break; 1224 result = comptypes_internal (TREE_TYPE (s1), TREE_TYPE (s2)); 1225 if (result == 0) 1226 break; 1227 if (result == 2) 1228 needs_warning = true; 1229 1230 if (TREE_CODE (s1) == FIELD_DECL 1231 && simple_cst_equal (DECL_FIELD_BIT_OFFSET (s1), 1232 DECL_FIELD_BIT_OFFSET (s2)) != 1) 1233 break; 1234 } 1235 if (s1 && s2) 1236 tu->val = 0; 1237 else 1238 tu->val = needs_warning ? 2 : 1; 1239 return tu->val; 1240 } 1241 1242 default: 1243 gcc_unreachable (); 1244 } 1245} 1246 1247/* Return 1 if two function types F1 and F2 are compatible. 1248 If either type specifies no argument types, 1249 the other must specify a fixed number of self-promoting arg types. 1250 Otherwise, if one type specifies only the number of arguments, 1251 the other must specify that number of self-promoting arg types. 1252 Otherwise, the argument types must match. */ 1253 1254static int 1255function_types_compatible_p (tree f1, tree f2) 1256{ 1257 tree args1, args2; 1258 /* 1 if no need for warning yet, 2 if warning cause has been seen. */ 1259 int val = 1; 1260 int val1; 1261 tree ret1, ret2; 1262 1263 ret1 = TREE_TYPE (f1); 1264 ret2 = TREE_TYPE (f2); 1265 1266 /* 'volatile' qualifiers on a function's return type used to mean 1267 the function is noreturn. */ 1268 if (TYPE_VOLATILE (ret1) != TYPE_VOLATILE (ret2)) 1269 pedwarn ("function return types not compatible due to %<volatile%>"); 1270 if (TYPE_VOLATILE (ret1)) 1271 ret1 = build_qualified_type (TYPE_MAIN_VARIANT (ret1), 1272 TYPE_QUALS (ret1) & ~TYPE_QUAL_VOLATILE); 1273 if (TYPE_VOLATILE (ret2)) 1274 ret2 = build_qualified_type (TYPE_MAIN_VARIANT (ret2), 1275 TYPE_QUALS (ret2) & ~TYPE_QUAL_VOLATILE); 1276 val = comptypes_internal (ret1, ret2); 1277 if (val == 0) 1278 return 0; 1279 1280 args1 = TYPE_ARG_TYPES (f1); 1281 args2 = TYPE_ARG_TYPES (f2); 1282 1283 /* An unspecified parmlist matches any specified parmlist 1284 whose argument types don't need default promotions. */ 1285 1286 if (args1 == 0) 1287 { 1288 if (!self_promoting_args_p (args2)) 1289 return 0; 1290 /* If one of these types comes from a non-prototype fn definition, 1291 compare that with the other type's arglist. 1292 If they don't match, ask for a warning (but no error). */ 1293 if (TYPE_ACTUAL_ARG_TYPES (f1) 1294 && 1 != type_lists_compatible_p (args2, TYPE_ACTUAL_ARG_TYPES (f1))) 1295 val = 2; 1296 return val; 1297 } 1298 if (args2 == 0) 1299 { 1300 if (!self_promoting_args_p (args1)) 1301 return 0; 1302 if (TYPE_ACTUAL_ARG_TYPES (f2) 1303 && 1 != type_lists_compatible_p (args1, TYPE_ACTUAL_ARG_TYPES (f2))) 1304 val = 2; 1305 return val; 1306 } 1307 1308 /* Both types have argument lists: compare them and propagate results. */ 1309 val1 = type_lists_compatible_p (args1, args2); 1310 return val1 != 1 ? val1 : val; 1311} 1312 1313/* Check two lists of types for compatibility, 1314 returning 0 for incompatible, 1 for compatible, 1315 or 2 for compatible with warning. */ 1316 1317static int 1318type_lists_compatible_p (tree args1, tree args2) 1319{ 1320 /* 1 if no need for warning yet, 2 if warning cause has been seen. */ 1321 int val = 1; 1322 int newval = 0; 1323 1324 while (1) 1325 { 1326 tree a1, mv1, a2, mv2; 1327 if (args1 == 0 && args2 == 0) 1328 return val; 1329 /* If one list is shorter than the other, 1330 they fail to match. */ 1331 if (args1 == 0 || args2 == 0) 1332 return 0; 1333 mv1 = a1 = TREE_VALUE (args1); 1334 mv2 = a2 = TREE_VALUE (args2); 1335 if (mv1 && mv1 != error_mark_node && TREE_CODE (mv1) != ARRAY_TYPE) 1336 mv1 = TYPE_MAIN_VARIANT (mv1); 1337 if (mv2 && mv2 != error_mark_node && TREE_CODE (mv2) != ARRAY_TYPE) 1338 mv2 = TYPE_MAIN_VARIANT (mv2); 1339 /* A null pointer instead of a type 1340 means there is supposed to be an argument 1341 but nothing is specified about what type it has. 1342 So match anything that self-promotes. */ 1343 if (a1 == 0) 1344 { 1345 if (c_type_promotes_to (a2) != a2) 1346 return 0; 1347 } 1348 else if (a2 == 0) 1349 { 1350 if (c_type_promotes_to (a1) != a1) 1351 return 0; 1352 } 1353 /* If one of the lists has an error marker, ignore this arg. */ 1354 else if (TREE_CODE (a1) == ERROR_MARK 1355 || TREE_CODE (a2) == ERROR_MARK) 1356 ; 1357 else if (!(newval = comptypes_internal (mv1, mv2))) 1358 { 1359 /* Allow wait (union {union wait *u; int *i} *) 1360 and wait (union wait *) to be compatible. */ 1361 if (TREE_CODE (a1) == UNION_TYPE 1362 && (TYPE_NAME (a1) == 0 1363 || TYPE_TRANSPARENT_UNION (a1)) 1364 && TREE_CODE (TYPE_SIZE (a1)) == INTEGER_CST 1365 && tree_int_cst_equal (TYPE_SIZE (a1), 1366 TYPE_SIZE (a2))) 1367 { 1368 tree memb; 1369 for (memb = TYPE_FIELDS (a1); 1370 memb; memb = TREE_CHAIN (memb)) 1371 { 1372 tree mv3 = TREE_TYPE (memb); 1373 if (mv3 && mv3 != error_mark_node 1374 && TREE_CODE (mv3) != ARRAY_TYPE) 1375 mv3 = TYPE_MAIN_VARIANT (mv3); 1376 if (comptypes_internal (mv3, mv2)) 1377 break; 1378 } 1379 if (memb == 0) 1380 return 0; 1381 } 1382 else if (TREE_CODE (a2) == UNION_TYPE 1383 && (TYPE_NAME (a2) == 0 1384 || TYPE_TRANSPARENT_UNION (a2)) 1385 && TREE_CODE (TYPE_SIZE (a2)) == INTEGER_CST 1386 && tree_int_cst_equal (TYPE_SIZE (a2), 1387 TYPE_SIZE (a1))) 1388 { 1389 tree memb; 1390 for (memb = TYPE_FIELDS (a2); 1391 memb; memb = TREE_CHAIN (memb)) 1392 { 1393 tree mv3 = TREE_TYPE (memb); 1394 if (mv3 && mv3 != error_mark_node 1395 && TREE_CODE (mv3) != ARRAY_TYPE) 1396 mv3 = TYPE_MAIN_VARIANT (mv3); 1397 if (comptypes_internal (mv3, mv1)) 1398 break; 1399 } 1400 if (memb == 0) 1401 return 0; 1402 } 1403 else 1404 return 0; 1405 } 1406 1407 /* comptypes said ok, but record if it said to warn. */ 1408 if (newval > val) 1409 val = newval; 1410 1411 args1 = TREE_CHAIN (args1); 1412 args2 = TREE_CHAIN (args2); 1413 } 1414} 1415 1416/* Compute the size to increment a pointer by. */ 1417 1418static tree 1419c_size_in_bytes (tree type) 1420{ 1421 enum tree_code code = TREE_CODE (type); 1422 1423 if (code == FUNCTION_TYPE || code == VOID_TYPE || code == ERROR_MARK) 1424 return size_one_node; 1425 1426 if (!COMPLETE_OR_VOID_TYPE_P (type)) 1427 { 1428 error ("arithmetic on pointer to an incomplete type"); 1429 return size_one_node; 1430 } 1431 1432 /* Convert in case a char is more than one unit. */ 1433 return size_binop (CEIL_DIV_EXPR, TYPE_SIZE_UNIT (type), 1434 size_int (TYPE_PRECISION (char_type_node) 1435 / BITS_PER_UNIT)); 1436} 1437 1438/* Return either DECL or its known constant value (if it has one). */ 1439 1440tree 1441decl_constant_value (tree decl) 1442{ 1443 if (/* Don't change a variable array bound or initial value to a constant 1444 in a place where a variable is invalid. Note that DECL_INITIAL 1445 isn't valid for a PARM_DECL. */ 1446 current_function_decl != 0 1447 && TREE_CODE (decl) != PARM_DECL 1448 && !TREE_THIS_VOLATILE (decl) 1449 && TREE_READONLY (decl) 1450 && DECL_INITIAL (decl) != 0 1451 && TREE_CODE (DECL_INITIAL (decl)) != ERROR_MARK 1452 /* This is invalid if initial value is not constant. 1453 If it has either a function call, a memory reference, 1454 or a variable, then re-evaluating it could give different results. */ 1455 && TREE_CONSTANT (DECL_INITIAL (decl)) 1456 /* Check for cases where this is sub-optimal, even though valid. */ 1457 && TREE_CODE (DECL_INITIAL (decl)) != CONSTRUCTOR) 1458 return DECL_INITIAL (decl); 1459 return decl; 1460} 1461 1462/* Return either DECL or its known constant value (if it has one), but 1463 return DECL if pedantic or DECL has mode BLKmode. This is for 1464 bug-compatibility with the old behavior of decl_constant_value 1465 (before GCC 3.0); every use of this function is a bug and it should 1466 be removed before GCC 3.1. It is not appropriate to use pedantic 1467 in a way that affects optimization, and BLKmode is probably not the 1468 right test for avoiding misoptimizations either. */ 1469 1470static tree 1471decl_constant_value_for_broken_optimization (tree decl) 1472{ 1473 tree ret; 1474 1475 if (pedantic || DECL_MODE (decl) == BLKmode) 1476 return decl; 1477 1478 ret = decl_constant_value (decl); 1479 /* Avoid unwanted tree sharing between the initializer and current 1480 function's body where the tree can be modified e.g. by the 1481 gimplifier. */ 1482 if (ret != decl && TREE_STATIC (decl)) 1483 ret = unshare_expr (ret); 1484 return ret; 1485} 1486 1487/* Convert the array expression EXP to a pointer. */ 1488static tree 1489array_to_pointer_conversion (tree exp) 1490{ 1491 tree orig_exp = exp; 1492 tree type = TREE_TYPE (exp); 1493 tree adr; 1494 tree restype = TREE_TYPE (type); 1495 tree ptrtype; 1496 1497 gcc_assert (TREE_CODE (type) == ARRAY_TYPE); 1498 1499 STRIP_TYPE_NOPS (exp); 1500 1501 if (TREE_NO_WARNING (orig_exp)) 1502 TREE_NO_WARNING (exp) = 1; 1503 1504 ptrtype = build_pointer_type (restype); 1505 1506 if (TREE_CODE (exp) == INDIRECT_REF) 1507 return convert (ptrtype, TREE_OPERAND (exp, 0)); 1508 1509 if (TREE_CODE (exp) == VAR_DECL) 1510 { 1511 /* We are making an ADDR_EXPR of ptrtype. This is a valid 1512 ADDR_EXPR because it's the best way of representing what 1513 happens in C when we take the address of an array and place 1514 it in a pointer to the element type. */ 1515 adr = build1 (ADDR_EXPR, ptrtype, exp); 1516 if (!c_mark_addressable (exp)) 1517 return error_mark_node; 1518 TREE_SIDE_EFFECTS (adr) = 0; /* Default would be, same as EXP. */ 1519 return adr; 1520 } 1521 1522 /* This way is better for a COMPONENT_REF since it can 1523 simplify the offset for a component. */ 1524 adr = build_unary_op (ADDR_EXPR, exp, 1); 1525 return convert (ptrtype, adr); 1526} 1527 1528/* Convert the function expression EXP to a pointer. */ 1529static tree 1530function_to_pointer_conversion (tree exp) 1531{ 1532 tree orig_exp = exp; 1533 1534 gcc_assert (TREE_CODE (TREE_TYPE (exp)) == FUNCTION_TYPE); 1535 1536 STRIP_TYPE_NOPS (exp); 1537 1538 if (TREE_NO_WARNING (orig_exp)) 1539 TREE_NO_WARNING (exp) = 1; 1540 1541 return build_unary_op (ADDR_EXPR, exp, 0); 1542} 1543 1544/* Perform the default conversion of arrays and functions to pointers. 1545 Return the result of converting EXP. For any other expression, just 1546 return EXP after removing NOPs. */ 1547 1548struct c_expr 1549default_function_array_conversion (struct c_expr exp) 1550{ 1551 tree orig_exp = exp.value; 1552 tree type = TREE_TYPE (exp.value); 1553 enum tree_code code = TREE_CODE (type); 1554 1555 switch (code) 1556 { 1557 case ARRAY_TYPE: 1558 { 1559 bool not_lvalue = false; 1560 bool lvalue_array_p; 1561 1562 while ((TREE_CODE (exp.value) == NON_LVALUE_EXPR 1563 || TREE_CODE (exp.value) == NOP_EXPR 1564 || TREE_CODE (exp.value) == CONVERT_EXPR) 1565 && TREE_TYPE (TREE_OPERAND (exp.value, 0)) == type) 1566 { 1567 if (TREE_CODE (exp.value) == NON_LVALUE_EXPR) 1568 not_lvalue = true; 1569 exp.value = TREE_OPERAND (exp.value, 0); 1570 } 1571 1572 if (TREE_NO_WARNING (orig_exp)) 1573 TREE_NO_WARNING (exp.value) = 1; 1574 1575 lvalue_array_p = !not_lvalue && lvalue_p (exp.value); 1576 if (!flag_isoc99 && !lvalue_array_p) 1577 { 1578 /* Before C99, non-lvalue arrays do not decay to pointers. 1579 Normally, using such an array would be invalid; but it can 1580 be used correctly inside sizeof or as a statement expression. 1581 Thus, do not give an error here; an error will result later. */ 1582 return exp; 1583 } 1584 1585 exp.value = array_to_pointer_conversion (exp.value); 1586 } 1587 break; 1588 case FUNCTION_TYPE: 1589 exp.value = function_to_pointer_conversion (exp.value); 1590 break; 1591 default: 1592 STRIP_TYPE_NOPS (exp.value); 1593 if (TREE_NO_WARNING (orig_exp)) 1594 TREE_NO_WARNING (exp.value) = 1; 1595 break; 1596 } 1597 1598 return exp; 1599} 1600 1601 1602/* EXP is an expression of integer type. Apply the integer promotions 1603 to it and return the promoted value. */ 1604 1605tree 1606perform_integral_promotions (tree exp) 1607{ 1608 tree type = TREE_TYPE (exp); 1609 enum tree_code code = TREE_CODE (type); 1610 1611 gcc_assert (INTEGRAL_TYPE_P (type)); 1612 1613 /* Normally convert enums to int, 1614 but convert wide enums to something wider. */ 1615 if (code == ENUMERAL_TYPE) 1616 { 1617 type = c_common_type_for_size (MAX (TYPE_PRECISION (type), 1618 TYPE_PRECISION (integer_type_node)), 1619 ((TYPE_PRECISION (type) 1620 >= TYPE_PRECISION (integer_type_node)) 1621 && TYPE_UNSIGNED (type))); 1622 1623 return convert (type, exp); 1624 } 1625 1626 /* ??? This should no longer be needed now bit-fields have their 1627 proper types. */ 1628 if (TREE_CODE (exp) == COMPONENT_REF 1629 && DECL_C_BIT_FIELD (TREE_OPERAND (exp, 1)) 1630 /* If it's thinner than an int, promote it like a 1631 c_promoting_integer_type_p, otherwise leave it alone. */ 1632 && 0 > compare_tree_int (DECL_SIZE (TREE_OPERAND (exp, 1)), 1633 TYPE_PRECISION (integer_type_node))) 1634 return convert (integer_type_node, exp); 1635 1636 if (c_promoting_integer_type_p (type)) 1637 { 1638 /* Preserve unsignedness if not really getting any wider. */ 1639 if (TYPE_UNSIGNED (type) 1640 && TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node)) 1641 return convert (unsigned_type_node, exp); 1642 1643 return convert (integer_type_node, exp); 1644 } 1645 1646 return exp; 1647} 1648 1649 1650/* Perform default promotions for C data used in expressions. 1651 Enumeral types or short or char are converted to int. 1652 In addition, manifest constants symbols are replaced by their values. */ 1653 1654tree 1655default_conversion (tree exp) 1656{ 1657 tree orig_exp; 1658 tree type = TREE_TYPE (exp); 1659 enum tree_code code = TREE_CODE (type); 1660 1661 /* Functions and arrays have been converted during parsing. */ 1662 gcc_assert (code != FUNCTION_TYPE); 1663 if (code == ARRAY_TYPE) 1664 return exp; 1665 1666 /* Constants can be used directly unless they're not loadable. */ 1667 if (TREE_CODE (exp) == CONST_DECL) 1668 exp = DECL_INITIAL (exp); 1669 1670 /* Replace a nonvolatile const static variable with its value unless 1671 it is an array, in which case we must be sure that taking the 1672 address of the array produces consistent results. */ 1673 else if (optimize && TREE_CODE (exp) == VAR_DECL && code != ARRAY_TYPE) 1674 { 1675 exp = decl_constant_value_for_broken_optimization (exp); 1676 type = TREE_TYPE (exp); 1677 } 1678 1679 /* Strip no-op conversions. */ 1680 orig_exp = exp; 1681 STRIP_TYPE_NOPS (exp); 1682 1683 if (TREE_NO_WARNING (orig_exp)) 1684 TREE_NO_WARNING (exp) = 1; 1685 1686 if (INTEGRAL_TYPE_P (type)) 1687 return perform_integral_promotions (exp); 1688 1689 if (code == VOID_TYPE) 1690 { 1691 error ("void value not ignored as it ought to be"); 1692 return error_mark_node; 1693 } 1694 return exp; 1695} 1696 1697/* Look up COMPONENT in a structure or union DECL. 1698 1699 If the component name is not found, returns NULL_TREE. Otherwise, 1700 the return value is a TREE_LIST, with each TREE_VALUE a FIELD_DECL 1701 stepping down the chain to the component, which is in the last 1702 TREE_VALUE of the list. Normally the list is of length one, but if 1703 the component is embedded within (nested) anonymous structures or 1704 unions, the list steps down the chain to the component. */ 1705 1706static tree 1707lookup_field (tree decl, tree component) 1708{ 1709 tree type = TREE_TYPE (decl); 1710 tree field; 1711 1712 /* If TYPE_LANG_SPECIFIC is set, then it is a sorted array of pointers 1713 to the field elements. Use a binary search on this array to quickly 1714 find the element. Otherwise, do a linear search. TYPE_LANG_SPECIFIC 1715 will always be set for structures which have many elements. */ 1716 1717 if (TYPE_LANG_SPECIFIC (type) && TYPE_LANG_SPECIFIC (type)->s) 1718 { 1719 int bot, top, half; 1720 tree *field_array = &TYPE_LANG_SPECIFIC (type)->s->elts[0]; 1721 1722 field = TYPE_FIELDS (type); 1723 bot = 0; 1724 top = TYPE_LANG_SPECIFIC (type)->s->len; 1725 while (top - bot > 1) 1726 { 1727 half = (top - bot + 1) >> 1; 1728 field = field_array[bot+half]; 1729 1730 if (DECL_NAME (field) == NULL_TREE) 1731 { 1732 /* Step through all anon unions in linear fashion. */ 1733 while (DECL_NAME (field_array[bot]) == NULL_TREE) 1734 { 1735 field = field_array[bot++]; 1736 if (TREE_CODE (TREE_TYPE (field)) == RECORD_TYPE 1737 || TREE_CODE (TREE_TYPE (field)) == UNION_TYPE) 1738 { 1739 tree anon = lookup_field (field, component); 1740 1741 if (anon) 1742 return tree_cons (NULL_TREE, field, anon); 1743 } 1744 } 1745 1746 /* Entire record is only anon unions. */ 1747 if (bot > top) 1748 return NULL_TREE; 1749 1750 /* Restart the binary search, with new lower bound. */ 1751 continue; 1752 } 1753 1754 if (DECL_NAME (field) == component) 1755 break; 1756 if (DECL_NAME (field) < component) 1757 bot += half; 1758 else 1759 top = bot + half; 1760 } 1761 1762 if (DECL_NAME (field_array[bot]) == component) 1763 field = field_array[bot]; 1764 else if (DECL_NAME (field) != component) 1765 return NULL_TREE; 1766 } 1767 else 1768 { 1769 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field)) 1770 { 1771 if (DECL_NAME (field) == NULL_TREE 1772 && (TREE_CODE (TREE_TYPE (field)) == RECORD_TYPE 1773 || TREE_CODE (TREE_TYPE (field)) == UNION_TYPE)) 1774 { 1775 tree anon = lookup_field (field, component); 1776 1777 if (anon) 1778 return tree_cons (NULL_TREE, field, anon); 1779 } 1780 1781 if (DECL_NAME (field) == component) 1782 break; 1783 } 1784 1785 if (field == NULL_TREE) 1786 return NULL_TREE; 1787 } 1788 1789 return tree_cons (NULL_TREE, field, NULL_TREE); 1790} 1791 1792/* Make an expression to refer to the COMPONENT field of 1793 structure or union value DATUM. COMPONENT is an IDENTIFIER_NODE. */ 1794 1795tree 1796build_component_ref (tree datum, tree component) 1797{ 1798 tree type = TREE_TYPE (datum); 1799 enum tree_code code = TREE_CODE (type); 1800 tree field = NULL; 1801 tree ref; 1802 1803 if (!objc_is_public (datum, component)) 1804 return error_mark_node; 1805 1806 /* See if there is a field or component with name COMPONENT. */ 1807 1808 if (code == RECORD_TYPE || code == UNION_TYPE) 1809 { 1810 if (!COMPLETE_TYPE_P (type)) 1811 { 1812 c_incomplete_type_error (NULL_TREE, type); 1813 return error_mark_node; 1814 } 1815 1816 field = lookup_field (datum, component); 1817 1818 if (!field) 1819 { 1820 error ("%qT has no member named %qE", type, component); 1821 return error_mark_node; 1822 } 1823 1824 /* Chain the COMPONENT_REFs if necessary down to the FIELD. 1825 This might be better solved in future the way the C++ front 1826 end does it - by giving the anonymous entities each a 1827 separate name and type, and then have build_component_ref 1828 recursively call itself. We can't do that here. */ 1829 do 1830 { 1831 tree subdatum = TREE_VALUE (field); 1832 int quals; 1833 tree subtype; 1834 1835 if (TREE_TYPE (subdatum) == error_mark_node) 1836 return error_mark_node; 1837 1838 quals = TYPE_QUALS (strip_array_types (TREE_TYPE (subdatum))); 1839 quals |= TYPE_QUALS (TREE_TYPE (datum)); 1840 subtype = c_build_qualified_type (TREE_TYPE (subdatum), quals); 1841 1842 ref = build3 (COMPONENT_REF, subtype, datum, subdatum, 1843 NULL_TREE); 1844 if (TREE_READONLY (datum) || TREE_READONLY (subdatum)) 1845 TREE_READONLY (ref) = 1; 1846 if (TREE_THIS_VOLATILE (datum) || TREE_THIS_VOLATILE (subdatum)) 1847 TREE_THIS_VOLATILE (ref) = 1; 1848 1849 if (TREE_DEPRECATED (subdatum)) 1850 warn_deprecated_use (subdatum); 1851 1852 datum = ref; 1853 1854 field = TREE_CHAIN (field); 1855 } 1856 while (field); 1857 1858 return ref; 1859 } 1860 else if (code != ERROR_MARK) 1861 error ("request for member %qE in something not a structure or union", 1862 component); 1863 1864 return error_mark_node; 1865} 1866 1867/* Given an expression PTR for a pointer, return an expression 1868 for the value pointed to. 1869 ERRORSTRING is the name of the operator to appear in error messages. */ 1870 1871tree 1872build_indirect_ref (tree ptr, const char *errorstring) 1873{ 1874 tree pointer = default_conversion (ptr); 1875 tree type = TREE_TYPE (pointer); 1876 1877 if (TREE_CODE (type) == POINTER_TYPE) 1878 { 1879 if (TREE_CODE (pointer) == CONVERT_EXPR 1880 || TREE_CODE (pointer) == NOP_EXPR 1881 || TREE_CODE (pointer) == VIEW_CONVERT_EXPR) 1882 { 1883 /* If a warning is issued, mark it to avoid duplicates from 1884 the backend. This only needs to be done at 1885 warn_strict_aliasing > 2. */ 1886 if (warn_strict_aliasing > 2) 1887 if (strict_aliasing_warning (TREE_TYPE (TREE_OPERAND (pointer, 0)), 1888 type, TREE_OPERAND (pointer, 0))) 1889 TREE_NO_WARNING (pointer) = 1; 1890 } 1891 1892 if (TREE_CODE (pointer) == ADDR_EXPR 1893 && (TREE_TYPE (TREE_OPERAND (pointer, 0)) 1894 == TREE_TYPE (type))) 1895 return TREE_OPERAND (pointer, 0); 1896 else 1897 { 1898 tree t = TREE_TYPE (type); 1899 tree ref; 1900 1901 ref = build1 (INDIRECT_REF, t, pointer); 1902 1903 if (!COMPLETE_OR_VOID_TYPE_P (t) && TREE_CODE (t) != ARRAY_TYPE) 1904 { 1905 error ("dereferencing pointer to incomplete type"); 1906 return error_mark_node; 1907 } 1908 if (VOID_TYPE_P (t) && skip_evaluation == 0) 1909 warning (0, "dereferencing %<void *%> pointer"); 1910 1911 /* We *must* set TREE_READONLY when dereferencing a pointer to const, 1912 so that we get the proper error message if the result is used 1913 to assign to. Also, &* is supposed to be a no-op. 1914 And ANSI C seems to specify that the type of the result 1915 should be the const type. */ 1916 /* A de-reference of a pointer to const is not a const. It is valid 1917 to change it via some other pointer. */ 1918 TREE_READONLY (ref) = TYPE_READONLY (t); 1919 TREE_SIDE_EFFECTS (ref) 1920 = TYPE_VOLATILE (t) || TREE_SIDE_EFFECTS (pointer); 1921 TREE_THIS_VOLATILE (ref) = TYPE_VOLATILE (t); 1922 return ref; 1923 } 1924 } 1925 else if (TREE_CODE (pointer) != ERROR_MARK) 1926 error ("invalid type argument of %qs", errorstring); 1927 return error_mark_node; 1928} 1929 1930/* This handles expressions of the form "a[i]", which denotes 1931 an array reference. 1932 1933 This is logically equivalent in C to *(a+i), but we may do it differently. 1934 If A is a variable or a member, we generate a primitive ARRAY_REF. 1935 This avoids forcing the array out of registers, and can work on 1936 arrays that are not lvalues (for example, members of structures returned 1937 by functions). */ 1938 1939tree 1940build_array_ref (tree array, tree index) 1941{ 1942 bool swapped = false; 1943 if (TREE_TYPE (array) == error_mark_node 1944 || TREE_TYPE (index) == error_mark_node) 1945 return error_mark_node; 1946 1947 if (TREE_CODE (TREE_TYPE (array)) != ARRAY_TYPE 1948 && TREE_CODE (TREE_TYPE (array)) != POINTER_TYPE) 1949 { 1950 tree temp; 1951 if (TREE_CODE (TREE_TYPE (index)) != ARRAY_TYPE 1952 && TREE_CODE (TREE_TYPE (index)) != POINTER_TYPE) 1953 { 1954 error ("subscripted value is neither array nor pointer"); 1955 return error_mark_node; 1956 } 1957 temp = array; 1958 array = index; 1959 index = temp; 1960 swapped = true; 1961 } 1962 1963 if (!INTEGRAL_TYPE_P (TREE_TYPE (index))) 1964 { 1965 error ("array subscript is not an integer"); 1966 return error_mark_node; 1967 } 1968 1969 if (TREE_CODE (TREE_TYPE (TREE_TYPE (array))) == FUNCTION_TYPE) 1970 { 1971 error ("subscripted value is pointer to function"); 1972 return error_mark_node; 1973 } 1974 1975 /* ??? Existing practice has been to warn only when the char 1976 index is syntactically the index, not for char[array]. */ 1977 if (!swapped) 1978 warn_array_subscript_with_type_char (index); 1979 1980 /* Apply default promotions *after* noticing character types. */ 1981 index = default_conversion (index); 1982 1983 gcc_assert (TREE_CODE (TREE_TYPE (index)) == INTEGER_TYPE); 1984 1985 if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE) 1986 { 1987 tree rval, type; 1988 1989 /* An array that is indexed by a non-constant 1990 cannot be stored in a register; we must be able to do 1991 address arithmetic on its address. 1992 Likewise an array of elements of variable size. */ 1993 if (TREE_CODE (index) != INTEGER_CST 1994 || (COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (array))) 1995 && TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array)))) != INTEGER_CST)) 1996 { 1997 if (!c_mark_addressable (array)) 1998 return error_mark_node; 1999 } 2000 /* An array that is indexed by a constant value which is not within 2001 the array bounds cannot be stored in a register either; because we 2002 would get a crash in store_bit_field/extract_bit_field when trying 2003 to access a non-existent part of the register. */ 2004 if (TREE_CODE (index) == INTEGER_CST 2005 && TYPE_DOMAIN (TREE_TYPE (array)) 2006 && !int_fits_type_p (index, TYPE_DOMAIN (TREE_TYPE (array)))) 2007 { 2008 if (!c_mark_addressable (array)) 2009 return error_mark_node; 2010 } 2011 2012 if (pedantic) 2013 { 2014 tree foo = array; 2015 while (TREE_CODE (foo) == COMPONENT_REF) 2016 foo = TREE_OPERAND (foo, 0); 2017 if (TREE_CODE (foo) == VAR_DECL && C_DECL_REGISTER (foo)) 2018 pedwarn ("ISO C forbids subscripting %<register%> array"); 2019 else if (!flag_isoc99 && !lvalue_p (foo)) 2020 pedwarn ("ISO C90 forbids subscripting non-lvalue array"); 2021 } 2022 2023 type = TREE_TYPE (TREE_TYPE (array)); 2024 if (TREE_CODE (type) != ARRAY_TYPE) 2025 type = TYPE_MAIN_VARIANT (type); 2026 rval = build4 (ARRAY_REF, type, array, index, NULL_TREE, NULL_TREE); 2027 /* Array ref is const/volatile if the array elements are 2028 or if the array is. */ 2029 TREE_READONLY (rval) 2030 |= (TYPE_READONLY (TREE_TYPE (TREE_TYPE (array))) 2031 | TREE_READONLY (array)); 2032 TREE_SIDE_EFFECTS (rval) 2033 |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array))) 2034 | TREE_SIDE_EFFECTS (array)); 2035 TREE_THIS_VOLATILE (rval) 2036 |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array))) 2037 /* This was added by rms on 16 Nov 91. 2038 It fixes vol struct foo *a; a->elts[1] 2039 in an inline function. 2040 Hope it doesn't break something else. */ 2041 | TREE_THIS_VOLATILE (array)); 2042 return require_complete_type (fold (rval)); 2043 } 2044 else 2045 { 2046 tree ar = default_conversion (array); 2047 2048 if (ar == error_mark_node) 2049 return ar; 2050 2051 gcc_assert (TREE_CODE (TREE_TYPE (ar)) == POINTER_TYPE); 2052 gcc_assert (TREE_CODE (TREE_TYPE (TREE_TYPE (ar))) != FUNCTION_TYPE); 2053 2054 return build_indirect_ref (build_binary_op (PLUS_EXPR, ar, index, 0), 2055 "array indexing"); 2056 } 2057} 2058 2059/* Build an external reference to identifier ID. FUN indicates 2060 whether this will be used for a function call. LOC is the source 2061 location of the identifier. */ 2062tree 2063build_external_ref (tree id, int fun, location_t loc) 2064{ 2065 tree ref; 2066 tree decl = lookup_name (id); 2067 2068 /* In Objective-C, an instance variable (ivar) may be preferred to 2069 whatever lookup_name() found. */ 2070 decl = objc_lookup_ivar (decl, id); 2071 2072 if (decl && decl != error_mark_node) 2073 ref = decl; 2074 else if (fun) 2075 /* Implicit function declaration. */ 2076 ref = implicitly_declare (id); 2077 else if (decl == error_mark_node) 2078 /* Don't complain about something that's already been 2079 complained about. */ 2080 return error_mark_node; 2081 else 2082 { 2083 undeclared_variable (id, loc); 2084 return error_mark_node; 2085 } 2086 2087 if (TREE_TYPE (ref) == error_mark_node) 2088 return error_mark_node; 2089 2090 if (TREE_DEPRECATED (ref)) 2091 warn_deprecated_use (ref); 2092 2093 if (!skip_evaluation) 2094 assemble_external (ref); 2095 TREE_USED (ref) = 1; 2096 2097 if (TREE_CODE (ref) == FUNCTION_DECL && !in_alignof) 2098 { 2099 if (!in_sizeof && !in_typeof) 2100 C_DECL_USED (ref) = 1; 2101 else if (DECL_INITIAL (ref) == 0 2102 && DECL_EXTERNAL (ref) 2103 && !TREE_PUBLIC (ref)) 2104 record_maybe_used_decl (ref); 2105 } 2106 2107 if (TREE_CODE (ref) == CONST_DECL) 2108 { 2109 used_types_insert (TREE_TYPE (ref)); 2110 ref = DECL_INITIAL (ref); 2111 TREE_CONSTANT (ref) = 1; 2112 TREE_INVARIANT (ref) = 1; 2113 } 2114 else if (current_function_decl != 0 2115 && !DECL_FILE_SCOPE_P (current_function_decl) 2116 && (TREE_CODE (ref) == VAR_DECL 2117 || TREE_CODE (ref) == PARM_DECL 2118 || TREE_CODE (ref) == FUNCTION_DECL)) 2119 { 2120 tree context = decl_function_context (ref); 2121 2122 if (context != 0 && context != current_function_decl) 2123 DECL_NONLOCAL (ref) = 1; 2124 } 2125 /* C99 6.7.4p3: An inline definition of a function with external 2126 linkage ... shall not contain a reference to an identifier with 2127 internal linkage. */ 2128 else if (current_function_decl != 0 2129 && DECL_DECLARED_INLINE_P (current_function_decl) 2130 && DECL_EXTERNAL (current_function_decl) 2131 && VAR_OR_FUNCTION_DECL_P (ref) 2132 && DECL_FILE_SCOPE_P (ref) 2133 && pedantic 2134 && (TREE_CODE (ref) != VAR_DECL || TREE_STATIC (ref)) 2135 && ! TREE_PUBLIC (ref)) 2136 pedwarn ("%H%qD is static but used in inline function %qD " 2137 "which is not static", &loc, ref, current_function_decl); 2138 2139 return ref; 2140} 2141 2142/* Record details of decls possibly used inside sizeof or typeof. */ 2143struct maybe_used_decl 2144{ 2145 /* The decl. */ 2146 tree decl; 2147 /* The level seen at (in_sizeof + in_typeof). */ 2148 int level; 2149 /* The next one at this level or above, or NULL. */ 2150 struct maybe_used_decl *next; 2151}; 2152 2153static struct maybe_used_decl *maybe_used_decls; 2154 2155/* Record that DECL, an undefined static function reference seen 2156 inside sizeof or typeof, might be used if the operand of sizeof is 2157 a VLA type or the operand of typeof is a variably modified 2158 type. */ 2159 2160static void 2161record_maybe_used_decl (tree decl) 2162{ 2163 struct maybe_used_decl *t = XOBNEW (&parser_obstack, struct maybe_used_decl); 2164 t->decl = decl; 2165 t->level = in_sizeof + in_typeof; 2166 t->next = maybe_used_decls; 2167 maybe_used_decls = t; 2168} 2169 2170/* Pop the stack of decls possibly used inside sizeof or typeof. If 2171 USED is false, just discard them. If it is true, mark them used 2172 (if no longer inside sizeof or typeof) or move them to the next 2173 level up (if still inside sizeof or typeof). */ 2174 2175void 2176pop_maybe_used (bool used) 2177{ 2178 struct maybe_used_decl *p = maybe_used_decls; 2179 int cur_level = in_sizeof + in_typeof; 2180 while (p && p->level > cur_level) 2181 { 2182 if (used) 2183 { 2184 if (cur_level == 0) 2185 C_DECL_USED (p->decl) = 1; 2186 else 2187 p->level = cur_level; 2188 } 2189 p = p->next; 2190 } 2191 if (!used || cur_level == 0) 2192 maybe_used_decls = p; 2193} 2194 2195/* Return the result of sizeof applied to EXPR. */ 2196 2197struct c_expr 2198c_expr_sizeof_expr (struct c_expr expr) 2199{ 2200 struct c_expr ret; 2201 if (expr.value == error_mark_node) 2202 { 2203 ret.value = error_mark_node; 2204 ret.original_code = ERROR_MARK; 2205 pop_maybe_used (false); 2206 } 2207 else 2208 { 2209 ret.value = c_sizeof (TREE_TYPE (expr.value)); 2210 ret.original_code = ERROR_MARK; 2211 if (c_vla_type_p (TREE_TYPE (expr.value))) 2212 { 2213 /* sizeof is evaluated when given a vla (C99 6.5.3.4p2). */ 2214 ret.value = build2 (COMPOUND_EXPR, TREE_TYPE (ret.value), expr.value, ret.value); 2215 } 2216 pop_maybe_used (C_TYPE_VARIABLE_SIZE (TREE_TYPE (expr.value))); 2217 } 2218 return ret; 2219} 2220 2221/* Return the result of sizeof applied to T, a structure for the type 2222 name passed to sizeof (rather than the type itself). */ 2223 2224struct c_expr 2225c_expr_sizeof_type (struct c_type_name *t) 2226{ 2227 tree type; 2228 struct c_expr ret; 2229 type = groktypename (t); 2230 ret.value = c_sizeof (type); 2231 ret.original_code = ERROR_MARK; 2232 pop_maybe_used (type != error_mark_node 2233 ? C_TYPE_VARIABLE_SIZE (type) : false); 2234 return ret; 2235} 2236 2237/* Build a function call to function FUNCTION with parameters PARAMS. 2238 PARAMS is a list--a chain of TREE_LIST nodes--in which the 2239 TREE_VALUE of each node is a parameter-expression. 2240 FUNCTION's data type may be a function type or a pointer-to-function. */ 2241 2242tree 2243build_function_call (tree function, tree params) 2244{ 2245 tree fntype, fundecl = 0; 2246 tree coerced_params; 2247 tree name = NULL_TREE, result; 2248 tree tem; 2249 2250 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */ 2251 STRIP_TYPE_NOPS (function); 2252 2253 /* Convert anything with function type to a pointer-to-function. */ 2254 if (TREE_CODE (function) == FUNCTION_DECL) 2255 { 2256 /* Implement type-directed function overloading for builtins. 2257 resolve_overloaded_builtin and targetm.resolve_overloaded_builtin 2258 handle all the type checking. The result is a complete expression 2259 that implements this function call. */ 2260 tem = resolve_overloaded_builtin (function, params); 2261 if (tem) 2262 return tem; 2263 2264 name = DECL_NAME (function); 2265 fundecl = function; 2266 } 2267 if (TREE_CODE (TREE_TYPE (function)) == FUNCTION_TYPE) 2268 function = function_to_pointer_conversion (function); 2269 2270 /* For Objective-C, convert any calls via a cast to OBJC_TYPE_REF 2271 expressions, like those used for ObjC messenger dispatches. */ 2272 function = objc_rewrite_function_call (function, params); 2273 2274 fntype = TREE_TYPE (function); 2275 2276 if (TREE_CODE (fntype) == ERROR_MARK) 2277 return error_mark_node; 2278 2279 if (!(TREE_CODE (fntype) == POINTER_TYPE 2280 && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE)) 2281 { 2282 error ("called object %qE is not a function", function); 2283 return error_mark_node; 2284 } 2285 2286 if (fundecl && TREE_THIS_VOLATILE (fundecl)) 2287 current_function_returns_abnormally = 1; 2288 2289 /* fntype now gets the type of function pointed to. */ 2290 fntype = TREE_TYPE (fntype); 2291 2292 /* Check that the function is called through a compatible prototype. 2293 If it is not, replace the call by a trap, wrapped up in a compound 2294 expression if necessary. This has the nice side-effect to prevent 2295 the tree-inliner from generating invalid assignment trees which may 2296 blow up in the RTL expander later. */ 2297 if ((TREE_CODE (function) == NOP_EXPR 2298 || TREE_CODE (function) == CONVERT_EXPR) 2299 && TREE_CODE (tem = TREE_OPERAND (function, 0)) == ADDR_EXPR 2300 && TREE_CODE (tem = TREE_OPERAND (tem, 0)) == FUNCTION_DECL 2301 && !comptypes (fntype, TREE_TYPE (tem))) 2302 { 2303 tree return_type = TREE_TYPE (fntype); 2304 tree trap = build_function_call (built_in_decls[BUILT_IN_TRAP], 2305 NULL_TREE); 2306 2307 /* This situation leads to run-time undefined behavior. We can't, 2308 therefore, simply error unless we can prove that all possible 2309 executions of the program must execute the code. */ 2310 warning (0, "function called through a non-compatible type"); 2311 2312 /* We can, however, treat "undefined" any way we please. 2313 Call abort to encourage the user to fix the program. */ 2314 inform ("if this code is reached, the program will abort"); 2315 2316 if (VOID_TYPE_P (return_type)) 2317 return trap; 2318 else 2319 { 2320 tree rhs; 2321 2322 if (AGGREGATE_TYPE_P (return_type)) 2323 rhs = build_compound_literal (return_type, 2324 build_constructor (return_type, 0)); 2325 else 2326 rhs = fold_convert (return_type, integer_zero_node); 2327 2328 return build2 (COMPOUND_EXPR, return_type, trap, rhs); 2329 } 2330 } 2331 2332 /* Convert the parameters to the types declared in the 2333 function prototype, or apply default promotions. */ 2334 2335 coerced_params 2336 = convert_arguments (TYPE_ARG_TYPES (fntype), params, function, fundecl); 2337 2338 if (coerced_params == error_mark_node) 2339 return error_mark_node; 2340 2341 /* Check that the arguments to the function are valid. */ 2342 2343 check_function_arguments (TYPE_ATTRIBUTES (fntype), coerced_params, 2344 TYPE_ARG_TYPES (fntype)); 2345 2346 if (require_constant_value) 2347 { 2348 result = fold_build3_initializer (CALL_EXPR, TREE_TYPE (fntype), 2349 function, coerced_params, NULL_TREE); 2350 2351 if (TREE_CONSTANT (result) 2352 && (name == NULL_TREE 2353 || strncmp (IDENTIFIER_POINTER (name), "__builtin_", 10) != 0)) 2354 pedwarn_init ("initializer element is not constant"); 2355 } 2356 else 2357 result = fold_build3 (CALL_EXPR, TREE_TYPE (fntype), 2358 function, coerced_params, NULL_TREE); 2359 2360 if (VOID_TYPE_P (TREE_TYPE (result))) 2361 return result; 2362 return require_complete_type (result); 2363} 2364 2365/* Convert the argument expressions in the list VALUES 2366 to the types in the list TYPELIST. The result is a list of converted 2367 argument expressions, unless there are too few arguments in which 2368 case it is error_mark_node. 2369 2370 If TYPELIST is exhausted, or when an element has NULL as its type, 2371 perform the default conversions. 2372 2373 PARMLIST is the chain of parm decls for the function being called. 2374 It may be 0, if that info is not available. 2375 It is used only for generating error messages. 2376 2377 FUNCTION is a tree for the called function. It is used only for 2378 error messages, where it is formatted with %qE. 2379 2380 This is also where warnings about wrong number of args are generated. 2381 2382 Both VALUES and the returned value are chains of TREE_LIST nodes 2383 with the elements of the list in the TREE_VALUE slots of those nodes. */ 2384 2385static tree 2386convert_arguments (tree typelist, tree values, tree function, tree fundecl) 2387{ 2388 tree typetail, valtail; 2389 tree result = NULL; 2390 int parmnum; 2391 tree selector; 2392 2393 /* Change pointer to function to the function itself for 2394 diagnostics. */ 2395 if (TREE_CODE (function) == ADDR_EXPR 2396 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL) 2397 function = TREE_OPERAND (function, 0); 2398 2399 /* Handle an ObjC selector specially for diagnostics. */ 2400 selector = objc_message_selector (); 2401 2402 /* Scan the given expressions and types, producing individual 2403 converted arguments and pushing them on RESULT in reverse order. */ 2404 2405 for (valtail = values, typetail = typelist, parmnum = 0; 2406 valtail; 2407 valtail = TREE_CHAIN (valtail), parmnum++) 2408 { 2409 tree type = typetail ? TREE_VALUE (typetail) : 0; 2410 tree val = TREE_VALUE (valtail); 2411 tree rname = function; 2412 int argnum = parmnum + 1; 2413 const char *invalid_func_diag; 2414 2415 if (type == void_type_node) 2416 { 2417 error ("too many arguments to function %qE", function); 2418 break; 2419 } 2420 2421 if (selector && argnum > 2) 2422 { 2423 rname = selector; 2424 argnum -= 2; 2425 } 2426 2427 STRIP_TYPE_NOPS (val); 2428 2429 val = require_complete_type (val); 2430 2431 if (type != 0) 2432 { 2433 /* Formal parm type is specified by a function prototype. */ 2434 tree parmval; 2435 2436 if (type == error_mark_node || !COMPLETE_TYPE_P (type)) 2437 { 2438 error ("type of formal parameter %d is incomplete", parmnum + 1); 2439 parmval = val; 2440 } 2441 else 2442 { 2443 /* Optionally warn about conversions that 2444 differ from the default conversions. */ 2445 if (warn_conversion || warn_traditional) 2446 { 2447 unsigned int formal_prec = TYPE_PRECISION (type); 2448 2449 if (INTEGRAL_TYPE_P (type) 2450 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE) 2451 warning (0, "passing argument %d of %qE as integer " 2452 "rather than floating due to prototype", 2453 argnum, rname); 2454 if (INTEGRAL_TYPE_P (type) 2455 && TREE_CODE (TREE_TYPE (val)) == COMPLEX_TYPE) 2456 warning (0, "passing argument %d of %qE as integer " 2457 "rather than complex due to prototype", 2458 argnum, rname); 2459 else if (TREE_CODE (type) == COMPLEX_TYPE 2460 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE) 2461 warning (0, "passing argument %d of %qE as complex " 2462 "rather than floating due to prototype", 2463 argnum, rname); 2464 else if (TREE_CODE (type) == REAL_TYPE 2465 && INTEGRAL_TYPE_P (TREE_TYPE (val))) 2466 warning (0, "passing argument %d of %qE as floating " 2467 "rather than integer due to prototype", 2468 argnum, rname); 2469 else if (TREE_CODE (type) == COMPLEX_TYPE 2470 && INTEGRAL_TYPE_P (TREE_TYPE (val))) 2471 warning (0, "passing argument %d of %qE as complex " 2472 "rather than integer due to prototype", 2473 argnum, rname); 2474 else if (TREE_CODE (type) == REAL_TYPE 2475 && TREE_CODE (TREE_TYPE (val)) == COMPLEX_TYPE) 2476 warning (0, "passing argument %d of %qE as floating " 2477 "rather than complex due to prototype", 2478 argnum, rname); 2479 /* ??? At some point, messages should be written about 2480 conversions between complex types, but that's too messy 2481 to do now. */ 2482 else if (TREE_CODE (type) == REAL_TYPE 2483 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE) 2484 { 2485 /* Warn if any argument is passed as `float', 2486 since without a prototype it would be `double'. */ 2487 if (formal_prec == TYPE_PRECISION (float_type_node) 2488 && type != dfloat32_type_node) 2489 warning (0, "passing argument %d of %qE as %<float%> " 2490 "rather than %<double%> due to prototype", 2491 argnum, rname); 2492 2493 /* Warn if mismatch between argument and prototype 2494 for decimal float types. Warn of conversions with 2495 binary float types and of precision narrowing due to 2496 prototype. */ 2497 else if (type != TREE_TYPE (val) 2498 && (type == dfloat32_type_node 2499 || type == dfloat64_type_node 2500 || type == dfloat128_type_node 2501 || TREE_TYPE (val) == dfloat32_type_node 2502 || TREE_TYPE (val) == dfloat64_type_node 2503 || TREE_TYPE (val) == dfloat128_type_node) 2504 && (formal_prec 2505 <= TYPE_PRECISION (TREE_TYPE (val)) 2506 || (type == dfloat128_type_node 2507 && (TREE_TYPE (val) 2508 != dfloat64_type_node 2509 && (TREE_TYPE (val) 2510 != dfloat32_type_node))) 2511 || (type == dfloat64_type_node 2512 && (TREE_TYPE (val) 2513 != dfloat32_type_node)))) 2514 warning (0, "passing argument %d of %qE as %qT " 2515 "rather than %qT due to prototype", 2516 argnum, rname, type, TREE_TYPE (val)); 2517 2518 } 2519 /* Detect integer changing in width or signedness. 2520 These warnings are only activated with 2521 -Wconversion, not with -Wtraditional. */ 2522 else if (warn_conversion && INTEGRAL_TYPE_P (type) 2523 && INTEGRAL_TYPE_P (TREE_TYPE (val))) 2524 { 2525 tree would_have_been = default_conversion (val); 2526 tree type1 = TREE_TYPE (would_have_been); 2527 2528 if (TREE_CODE (type) == ENUMERAL_TYPE 2529 && (TYPE_MAIN_VARIANT (type) 2530 == TYPE_MAIN_VARIANT (TREE_TYPE (val)))) 2531 /* No warning if function asks for enum 2532 and the actual arg is that enum type. */ 2533 ; 2534 else if (formal_prec != TYPE_PRECISION (type1)) 2535 warning (OPT_Wconversion, "passing argument %d of %qE " 2536 "with different width due to prototype", 2537 argnum, rname); 2538 else if (TYPE_UNSIGNED (type) == TYPE_UNSIGNED (type1)) 2539 ; 2540 /* Don't complain if the formal parameter type 2541 is an enum, because we can't tell now whether 2542 the value was an enum--even the same enum. */ 2543 else if (TREE_CODE (type) == ENUMERAL_TYPE) 2544 ; 2545 else if (TREE_CODE (val) == INTEGER_CST 2546 && int_fits_type_p (val, type)) 2547 /* Change in signedness doesn't matter 2548 if a constant value is unaffected. */ 2549 ; 2550 /* If the value is extended from a narrower 2551 unsigned type, it doesn't matter whether we 2552 pass it as signed or unsigned; the value 2553 certainly is the same either way. */ 2554 else if (TYPE_PRECISION (TREE_TYPE (val)) < TYPE_PRECISION (type) 2555 && TYPE_UNSIGNED (TREE_TYPE (val))) 2556 ; 2557 else if (TYPE_UNSIGNED (type)) 2558 warning (OPT_Wconversion, "passing argument %d of %qE " 2559 "as unsigned due to prototype", 2560 argnum, rname); 2561 else 2562 warning (OPT_Wconversion, "passing argument %d of %qE " 2563 "as signed due to prototype", argnum, rname); 2564 } 2565 } 2566 2567 parmval = convert_for_assignment (type, val, ic_argpass, 2568 fundecl, function, 2569 parmnum + 1); 2570 2571 if (targetm.calls.promote_prototypes (fundecl ? TREE_TYPE (fundecl) : 0) 2572 && INTEGRAL_TYPE_P (type) 2573 && (TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node))) 2574 parmval = default_conversion (parmval); 2575 } 2576 result = tree_cons (NULL_TREE, parmval, result); 2577 } 2578 else if (TREE_CODE (TREE_TYPE (val)) == REAL_TYPE 2579 && (TYPE_PRECISION (TREE_TYPE (val)) 2580 < TYPE_PRECISION (double_type_node)) 2581 && !DECIMAL_FLOAT_MODE_P (TYPE_MODE (TREE_TYPE (val)))) 2582 /* Convert `float' to `double'. */ 2583 result = tree_cons (NULL_TREE, convert (double_type_node, val), result); 2584 else if ((invalid_func_diag = 2585 targetm.calls.invalid_arg_for_unprototyped_fn (typelist, fundecl, val))) 2586 { 2587 error (invalid_func_diag); 2588 return error_mark_node; 2589 } 2590 else 2591 /* Convert `short' and `char' to full-size `int'. */ 2592 result = tree_cons (NULL_TREE, default_conversion (val), result); 2593 2594 if (typetail) 2595 typetail = TREE_CHAIN (typetail); 2596 } 2597 2598 if (typetail != 0 && TREE_VALUE (typetail) != void_type_node) 2599 { 2600 error ("too few arguments to function %qE", function); 2601 return error_mark_node; 2602 } 2603 2604 return nreverse (result); 2605} 2606 2607/* This is the entry point used by the parser to build unary operators 2608 in the input. CODE, a tree_code, specifies the unary operator, and 2609 ARG is the operand. For unary plus, the C parser currently uses 2610 CONVERT_EXPR for code. */ 2611 2612struct c_expr 2613parser_build_unary_op (enum tree_code code, struct c_expr arg) 2614{ 2615 struct c_expr result; 2616 2617 result.original_code = ERROR_MARK; 2618 result.value = build_unary_op (code, arg.value, 0); 2619 overflow_warning (result.value); 2620 return result; 2621} 2622 2623/* This is the entry point used by the parser to build binary operators 2624 in the input. CODE, a tree_code, specifies the binary operator, and 2625 ARG1 and ARG2 are the operands. In addition to constructing the 2626 expression, we check for operands that were written with other binary 2627 operators in a way that is likely to confuse the user. */ 2628 2629struct c_expr 2630parser_build_binary_op (enum tree_code code, struct c_expr arg1, 2631 struct c_expr arg2) 2632{ 2633 struct c_expr result; 2634 2635 enum tree_code code1 = arg1.original_code; 2636 enum tree_code code2 = arg2.original_code; 2637 2638 result.value = build_binary_op (code, arg1.value, arg2.value, 1); 2639 result.original_code = code; 2640 2641 if (TREE_CODE (result.value) == ERROR_MARK) 2642 return result; 2643 2644 /* Check for cases such as x+y<<z which users are likely 2645 to misinterpret. */ 2646 if (warn_parentheses) 2647 warn_about_parentheses (code, code1, code2); 2648 2649 /* Warn about comparisons against string literals, with the exception 2650 of testing for equality or inequality of a string literal with NULL. */ 2651 if (code == EQ_EXPR || code == NE_EXPR) 2652 { 2653 if ((code1 == STRING_CST && !integer_zerop (arg2.value)) 2654 || (code2 == STRING_CST && !integer_zerop (arg1.value))) 2655 warning (OPT_Waddress, 2656 "comparison with string literal results in unspecified behaviour"); 2657 } 2658 else if (TREE_CODE_CLASS (code) == tcc_comparison 2659 && (code1 == STRING_CST || code2 == STRING_CST)) 2660 warning (OPT_Waddress, 2661 "comparison with string literal results in unspecified behaviour"); 2662 2663 overflow_warning (result.value); 2664 2665 return result; 2666} 2667 2668/* Return a tree for the difference of pointers OP0 and OP1. 2669 The resulting tree has type int. */ 2670 2671static tree 2672pointer_diff (tree op0, tree op1) 2673{ 2674 tree restype = ptrdiff_type_node; 2675 2676 tree target_type = TREE_TYPE (TREE_TYPE (op0)); 2677 tree con0, con1, lit0, lit1; 2678 tree orig_op1 = op1; 2679 2680 if (pedantic || warn_pointer_arith) 2681 { 2682 if (TREE_CODE (target_type) == VOID_TYPE) 2683 pedwarn ("pointer of type %<void *%> used in subtraction"); 2684 if (TREE_CODE (target_type) == FUNCTION_TYPE) 2685 pedwarn ("pointer to a function used in subtraction"); 2686 } 2687 2688 /* If the conversion to ptrdiff_type does anything like widening or 2689 converting a partial to an integral mode, we get a convert_expression 2690 that is in the way to do any simplifications. 2691 (fold-const.c doesn't know that the extra bits won't be needed. 2692 split_tree uses STRIP_SIGN_NOPS, which leaves conversions to a 2693 different mode in place.) 2694 So first try to find a common term here 'by hand'; we want to cover 2695 at least the cases that occur in legal static initializers. */ 2696 if ((TREE_CODE (op0) == NOP_EXPR || TREE_CODE (op0) == CONVERT_EXPR) 2697 && (TYPE_PRECISION (TREE_TYPE (op0)) 2698 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op0, 0))))) 2699 con0 = TREE_OPERAND (op0, 0); 2700 else 2701 con0 = op0; 2702 if ((TREE_CODE (op1) == NOP_EXPR || TREE_CODE (op1) == CONVERT_EXPR) 2703 && (TYPE_PRECISION (TREE_TYPE (op1)) 2704 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op1, 0))))) 2705 con1 = TREE_OPERAND (op1, 0); 2706 else 2707 con1 = op1; 2708 2709 if (TREE_CODE (con0) == PLUS_EXPR) 2710 { 2711 lit0 = TREE_OPERAND (con0, 1); 2712 con0 = TREE_OPERAND (con0, 0); 2713 } 2714 else 2715 lit0 = integer_zero_node; 2716 2717 if (TREE_CODE (con1) == PLUS_EXPR) 2718 { 2719 lit1 = TREE_OPERAND (con1, 1); 2720 con1 = TREE_OPERAND (con1, 0); 2721 } 2722 else 2723 lit1 = integer_zero_node; 2724 2725 if (operand_equal_p (con0, con1, 0)) 2726 { 2727 op0 = lit0; 2728 op1 = lit1; 2729 } 2730 2731 2732 /* First do the subtraction as integers; 2733 then drop through to build the divide operator. 2734 Do not do default conversions on the minus operator 2735 in case restype is a short type. */ 2736 2737 op0 = build_binary_op (MINUS_EXPR, convert (restype, op0), 2738 convert (restype, op1), 0); 2739 /* This generates an error if op1 is pointer to incomplete type. */ 2740 if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (TREE_TYPE (orig_op1)))) 2741 error ("arithmetic on pointer to an incomplete type"); 2742 2743 /* This generates an error if op0 is pointer to incomplete type. */ 2744 op1 = c_size_in_bytes (target_type); 2745 2746 /* Divide by the size, in easiest possible way. */ 2747 return fold_build2 (EXACT_DIV_EXPR, restype, op0, convert (restype, op1)); 2748} 2749 2750/* Construct and perhaps optimize a tree representation 2751 for a unary operation. CODE, a tree_code, specifies the operation 2752 and XARG is the operand. 2753 For any CODE other than ADDR_EXPR, FLAG nonzero suppresses 2754 the default promotions (such as from short to int). 2755 For ADDR_EXPR, the default promotions are not applied; FLAG nonzero 2756 allows non-lvalues; this is only used to handle conversion of non-lvalue 2757 arrays to pointers in C99. */ 2758 2759tree 2760build_unary_op (enum tree_code code, tree xarg, int flag) 2761{ 2762 /* No default_conversion here. It causes trouble for ADDR_EXPR. */ 2763 tree arg = xarg; 2764 tree argtype = 0; 2765 enum tree_code typecode = TREE_CODE (TREE_TYPE (arg)); 2766 tree val; 2767 int noconvert = flag; 2768 const char *invalid_op_diag; 2769 2770 if (typecode == ERROR_MARK) 2771 return error_mark_node; 2772 if (typecode == ENUMERAL_TYPE || typecode == BOOLEAN_TYPE) 2773 typecode = INTEGER_TYPE; 2774 2775 if ((invalid_op_diag 2776 = targetm.invalid_unary_op (code, TREE_TYPE (xarg)))) 2777 { 2778 error (invalid_op_diag); 2779 return error_mark_node; 2780 } 2781 2782 switch (code) 2783 { 2784 case CONVERT_EXPR: 2785 /* This is used for unary plus, because a CONVERT_EXPR 2786 is enough to prevent anybody from looking inside for 2787 associativity, but won't generate any code. */ 2788 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE 2789 || typecode == COMPLEX_TYPE 2790 || typecode == VECTOR_TYPE)) 2791 { 2792 error ("wrong type argument to unary plus"); 2793 return error_mark_node; 2794 } 2795 else if (!noconvert) 2796 arg = default_conversion (arg); 2797 arg = non_lvalue (arg); 2798 break; 2799 2800 case NEGATE_EXPR: 2801 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE 2802 || typecode == COMPLEX_TYPE 2803 || typecode == VECTOR_TYPE)) 2804 { 2805 error ("wrong type argument to unary minus"); 2806 return error_mark_node; 2807 } 2808 else if (!noconvert) 2809 arg = default_conversion (arg); 2810 break; 2811 2812 case BIT_NOT_EXPR: 2813 if (typecode == INTEGER_TYPE || typecode == VECTOR_TYPE) 2814 { 2815 if (!noconvert) 2816 arg = default_conversion (arg); 2817 } 2818 else if (typecode == COMPLEX_TYPE) 2819 { 2820 code = CONJ_EXPR; 2821 if (pedantic) 2822 pedwarn ("ISO C does not support %<~%> for complex conjugation"); 2823 if (!noconvert) 2824 arg = default_conversion (arg); 2825 } 2826 else 2827 { 2828 error ("wrong type argument to bit-complement"); 2829 return error_mark_node; 2830 } 2831 break; 2832 2833 case ABS_EXPR: 2834 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE)) 2835 { 2836 error ("wrong type argument to abs"); 2837 return error_mark_node; 2838 } 2839 else if (!noconvert) 2840 arg = default_conversion (arg); 2841 break; 2842 2843 case CONJ_EXPR: 2844 /* Conjugating a real value is a no-op, but allow it anyway. */ 2845 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE 2846 || typecode == COMPLEX_TYPE)) 2847 { 2848 error ("wrong type argument to conjugation"); 2849 return error_mark_node; 2850 } 2851 else if (!noconvert) 2852 arg = default_conversion (arg); 2853 break; 2854 2855 case TRUTH_NOT_EXPR: 2856 if (typecode != INTEGER_TYPE 2857 && typecode != REAL_TYPE && typecode != POINTER_TYPE 2858 && typecode != COMPLEX_TYPE) 2859 { 2860 error ("wrong type argument to unary exclamation mark"); 2861 return error_mark_node; 2862 } 2863 arg = c_objc_common_truthvalue_conversion (arg); 2864 return invert_truthvalue (arg); 2865 2866 case REALPART_EXPR: 2867 if (TREE_CODE (arg) == COMPLEX_CST) 2868 return TREE_REALPART (arg); 2869 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE) 2870 return fold_build1 (REALPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg); 2871 else 2872 return arg; 2873 2874 case IMAGPART_EXPR: 2875 if (TREE_CODE (arg) == COMPLEX_CST) 2876 return TREE_IMAGPART (arg); 2877 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE) 2878 return fold_build1 (IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg); 2879 else 2880 return convert (TREE_TYPE (arg), integer_zero_node); 2881 2882 case PREINCREMENT_EXPR: 2883 case POSTINCREMENT_EXPR: 2884 case PREDECREMENT_EXPR: 2885 case POSTDECREMENT_EXPR: 2886 2887 /* Increment or decrement the real part of the value, 2888 and don't change the imaginary part. */ 2889 if (typecode == COMPLEX_TYPE) 2890 { 2891 tree real, imag; 2892 2893 if (pedantic) 2894 pedwarn ("ISO C does not support %<++%> and %<--%>" 2895 " on complex types"); 2896 2897 arg = stabilize_reference (arg); 2898 real = build_unary_op (REALPART_EXPR, arg, 1); 2899 imag = build_unary_op (IMAGPART_EXPR, arg, 1); 2900 return build2 (COMPLEX_EXPR, TREE_TYPE (arg), 2901 build_unary_op (code, real, 1), imag); 2902 } 2903 2904 /* Report invalid types. */ 2905 2906 if (typecode != POINTER_TYPE 2907 && typecode != INTEGER_TYPE && typecode != REAL_TYPE) 2908 { 2909 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR) 2910 error ("wrong type argument to increment"); 2911 else 2912 error ("wrong type argument to decrement"); 2913 2914 return error_mark_node; 2915 } 2916 2917 { 2918 tree inc; 2919 tree result_type = TREE_TYPE (arg); 2920 2921 arg = get_unwidened (arg, 0); 2922 argtype = TREE_TYPE (arg); 2923 2924 /* Compute the increment. */ 2925 2926 if (typecode == POINTER_TYPE) 2927 { 2928 /* If pointer target is an undefined struct, 2929 we just cannot know how to do the arithmetic. */ 2930 if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (result_type))) 2931 { 2932 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR) 2933 error ("increment of pointer to unknown structure"); 2934 else 2935 error ("decrement of pointer to unknown structure"); 2936 } 2937 else if ((pedantic || warn_pointer_arith) 2938 && (TREE_CODE (TREE_TYPE (result_type)) == FUNCTION_TYPE 2939 || TREE_CODE (TREE_TYPE (result_type)) == VOID_TYPE)) 2940 { 2941 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR) 2942 pedwarn ("wrong type argument to increment"); 2943 else 2944 pedwarn ("wrong type argument to decrement"); 2945 } 2946 2947 inc = c_size_in_bytes (TREE_TYPE (result_type)); 2948 } 2949 else 2950 inc = integer_one_node; 2951 2952 inc = convert (argtype, inc); 2953 2954 /* Complain about anything else that is not a true lvalue. */ 2955 if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR 2956 || code == POSTINCREMENT_EXPR) 2957 ? lv_increment 2958 : lv_decrement))) 2959 return error_mark_node; 2960 2961 /* Report a read-only lvalue. */ 2962 if (TREE_READONLY (arg)) 2963 { 2964 readonly_error (arg, 2965 ((code == PREINCREMENT_EXPR 2966 || code == POSTINCREMENT_EXPR) 2967 ? lv_increment : lv_decrement)); 2968 return error_mark_node; 2969 } 2970 2971 if (TREE_CODE (TREE_TYPE (arg)) == BOOLEAN_TYPE) 2972 val = boolean_increment (code, arg); 2973 else 2974 val = build2 (code, TREE_TYPE (arg), arg, inc); 2975 TREE_SIDE_EFFECTS (val) = 1; 2976 val = convert (result_type, val); 2977 if (TREE_CODE (val) != code) 2978 TREE_NO_WARNING (val) = 1; 2979 return val; 2980 } 2981 2982 case ADDR_EXPR: 2983 /* Note that this operation never does default_conversion. */ 2984 2985 /* Let &* cancel out to simplify resulting code. */ 2986 if (TREE_CODE (arg) == INDIRECT_REF) 2987 { 2988 /* Don't let this be an lvalue. */ 2989 if (lvalue_p (TREE_OPERAND (arg, 0))) 2990 return non_lvalue (TREE_OPERAND (arg, 0)); 2991 return TREE_OPERAND (arg, 0); 2992 } 2993 2994 /* For &x[y], return x+y */ 2995 if (TREE_CODE (arg) == ARRAY_REF) 2996 { 2997 tree op0 = TREE_OPERAND (arg, 0); 2998 if (!c_mark_addressable (op0)) 2999 return error_mark_node; 3000 return build_binary_op (PLUS_EXPR, 3001 (TREE_CODE (TREE_TYPE (op0)) == ARRAY_TYPE 3002 ? array_to_pointer_conversion (op0) 3003 : op0), 3004 TREE_OPERAND (arg, 1), 1); 3005 } 3006 3007 /* Anything not already handled and not a true memory reference 3008 or a non-lvalue array is an error. */ 3009 else if (typecode != FUNCTION_TYPE && !flag 3010 && !lvalue_or_else (arg, lv_addressof)) 3011 return error_mark_node; 3012 3013 /* Ordinary case; arg is a COMPONENT_REF or a decl. */ 3014 argtype = TREE_TYPE (arg); 3015 3016 /* If the lvalue is const or volatile, merge that into the type 3017 to which the address will point. Note that you can't get a 3018 restricted pointer by taking the address of something, so we 3019 only have to deal with `const' and `volatile' here. */ 3020 if ((DECL_P (arg) || REFERENCE_CLASS_P (arg)) 3021 && (TREE_READONLY (arg) || TREE_THIS_VOLATILE (arg))) 3022 argtype = c_build_type_variant (argtype, 3023 TREE_READONLY (arg), 3024 TREE_THIS_VOLATILE (arg)); 3025 3026 if (!c_mark_addressable (arg)) 3027 return error_mark_node; 3028 3029 gcc_assert (TREE_CODE (arg) != COMPONENT_REF 3030 || !DECL_C_BIT_FIELD (TREE_OPERAND (arg, 1))); 3031 3032 argtype = build_pointer_type (argtype); 3033 3034 /* ??? Cope with user tricks that amount to offsetof. Delete this 3035 when we have proper support for integer constant expressions. */ 3036 val = get_base_address (arg); 3037 if (val && TREE_CODE (val) == INDIRECT_REF 3038 && TREE_CONSTANT (TREE_OPERAND (val, 0))) 3039 { 3040 tree op0 = fold_convert (argtype, fold_offsetof (arg, val)), op1; 3041 3042 op1 = fold_convert (argtype, TREE_OPERAND (val, 0)); 3043 return fold_build2 (PLUS_EXPR, argtype, op0, op1); 3044 } 3045 3046 val = build1 (ADDR_EXPR, argtype, arg); 3047 3048 return val; 3049 3050 default: 3051 gcc_unreachable (); 3052 } 3053 3054 if (argtype == 0) 3055 argtype = TREE_TYPE (arg); 3056 return require_constant_value ? fold_build1_initializer (code, argtype, arg) 3057 : fold_build1 (code, argtype, arg); 3058} 3059 3060/* Return nonzero if REF is an lvalue valid for this language. 3061 Lvalues can be assigned, unless their type has TYPE_READONLY. 3062 Lvalues can have their address taken, unless they have C_DECL_REGISTER. */ 3063 3064static int 3065lvalue_p (tree ref) 3066{ 3067 enum tree_code code = TREE_CODE (ref); 3068 3069 switch (code) 3070 { 3071 case REALPART_EXPR: 3072 case IMAGPART_EXPR: 3073 case COMPONENT_REF: 3074 return lvalue_p (TREE_OPERAND (ref, 0)); 3075 3076 case COMPOUND_LITERAL_EXPR: 3077 case STRING_CST: 3078 return 1; 3079 3080 case INDIRECT_REF: 3081 case ARRAY_REF: 3082 case VAR_DECL: 3083 case PARM_DECL: 3084 case RESULT_DECL: 3085 case ERROR_MARK: 3086 return (TREE_CODE (TREE_TYPE (ref)) != FUNCTION_TYPE 3087 && TREE_CODE (TREE_TYPE (ref)) != METHOD_TYPE); 3088 3089 case BIND_EXPR: 3090 return TREE_CODE (TREE_TYPE (ref)) == ARRAY_TYPE; 3091 3092 default: 3093 return 0; 3094 } 3095} 3096 3097/* Give an error for storing in something that is 'const'. */ 3098 3099static void 3100readonly_error (tree arg, enum lvalue_use use) 3101{ 3102 gcc_assert (use == lv_assign || use == lv_increment || use == lv_decrement 3103 || use == lv_asm); 3104 /* Using this macro rather than (for example) arrays of messages 3105 ensures that all the format strings are checked at compile 3106 time. */ 3107#define READONLY_MSG(A, I, D, AS) (use == lv_assign ? (A) \ 3108 : (use == lv_increment ? (I) \ 3109 : (use == lv_decrement ? (D) : (AS)))) 3110 if (TREE_CODE (arg) == COMPONENT_REF) 3111 { 3112 if (TYPE_READONLY (TREE_TYPE (TREE_OPERAND (arg, 0)))) 3113 readonly_error (TREE_OPERAND (arg, 0), use); 3114 else 3115 error (READONLY_MSG (G_("assignment of read-only member %qD"), 3116 G_("increment of read-only member %qD"), 3117 G_("decrement of read-only member %qD"), 3118 G_("read-only member %qD used as %<asm%> output")), 3119 TREE_OPERAND (arg, 1)); 3120 } 3121 else if (TREE_CODE (arg) == VAR_DECL) 3122 error (READONLY_MSG (G_("assignment of read-only variable %qD"), 3123 G_("increment of read-only variable %qD"), 3124 G_("decrement of read-only variable %qD"), 3125 G_("read-only variable %qD used as %<asm%> output")), 3126 arg); 3127 else 3128 error (READONLY_MSG (G_("assignment of read-only location"), 3129 G_("increment of read-only location"), 3130 G_("decrement of read-only location"), 3131 G_("read-only location used as %<asm%> output"))); 3132} 3133 3134 3135/* Return nonzero if REF is an lvalue valid for this language; 3136 otherwise, print an error message and return zero. USE says 3137 how the lvalue is being used and so selects the error message. */ 3138 3139static int 3140lvalue_or_else (tree ref, enum lvalue_use use) 3141{ 3142 int win = lvalue_p (ref); 3143 3144 if (!win) 3145 lvalue_error (use); 3146 3147 return win; 3148} 3149 3150/* Mark EXP saying that we need to be able to take the 3151 address of it; it should not be allocated in a register. 3152 Returns true if successful. */ 3153 3154bool 3155c_mark_addressable (tree exp) 3156{ 3157 tree x = exp; 3158 3159 while (1) 3160 switch (TREE_CODE (x)) 3161 { 3162 case COMPONENT_REF: 3163 if (DECL_C_BIT_FIELD (TREE_OPERAND (x, 1))) 3164 { 3165 error 3166 ("cannot take address of bit-field %qD", TREE_OPERAND (x, 1)); 3167 return false; 3168 } 3169 3170 /* ... fall through ... */ 3171 3172 case ADDR_EXPR: 3173 case ARRAY_REF: 3174 case REALPART_EXPR: 3175 case IMAGPART_EXPR: 3176 x = TREE_OPERAND (x, 0); 3177 break; 3178 3179 case COMPOUND_LITERAL_EXPR: 3180 case CONSTRUCTOR: 3181 TREE_ADDRESSABLE (x) = 1; 3182 return true; 3183 3184 case VAR_DECL: 3185 case CONST_DECL: 3186 case PARM_DECL: 3187 case RESULT_DECL: 3188 if (C_DECL_REGISTER (x) 3189 && DECL_NONLOCAL (x)) 3190 { 3191 if (TREE_PUBLIC (x) || TREE_STATIC (x) || DECL_EXTERNAL (x)) 3192 { 3193 error 3194 ("global register variable %qD used in nested function", x); 3195 return false; 3196 } 3197 pedwarn ("register variable %qD used in nested function", x); 3198 } 3199 else if (C_DECL_REGISTER (x)) 3200 { 3201 if (TREE_PUBLIC (x) || TREE_STATIC (x) || DECL_EXTERNAL (x)) 3202 error ("address of global register variable %qD requested", x); 3203 else 3204 error ("address of register variable %qD requested", x); 3205 return false; 3206 } 3207 3208 /* drops in */ 3209 case FUNCTION_DECL: 3210 TREE_ADDRESSABLE (x) = 1; 3211 /* drops out */ 3212 default: 3213 return true; 3214 } 3215} 3216 3217/* Build and return a conditional expression IFEXP ? OP1 : OP2. */ 3218 3219tree 3220build_conditional_expr (tree ifexp, tree op1, tree op2) 3221{ 3222 tree type1; 3223 tree type2; 3224 enum tree_code code1; 3225 enum tree_code code2; 3226 tree result_type = NULL; 3227 tree orig_op1 = op1, orig_op2 = op2; 3228 3229 /* Promote both alternatives. */ 3230 3231 if (TREE_CODE (TREE_TYPE (op1)) != VOID_TYPE) 3232 op1 = default_conversion (op1); 3233 if (TREE_CODE (TREE_TYPE (op2)) != VOID_TYPE) 3234 op2 = default_conversion (op2); 3235 3236 if (TREE_CODE (ifexp) == ERROR_MARK 3237 || TREE_CODE (TREE_TYPE (op1)) == ERROR_MARK 3238 || TREE_CODE (TREE_TYPE (op2)) == ERROR_MARK) 3239 return error_mark_node; 3240 3241 type1 = TREE_TYPE (op1); 3242 code1 = TREE_CODE (type1); 3243 type2 = TREE_TYPE (op2); 3244 code2 = TREE_CODE (type2); 3245 3246 /* C90 does not permit non-lvalue arrays in conditional expressions. 3247 In C99 they will be pointers by now. */ 3248 if (code1 == ARRAY_TYPE || code2 == ARRAY_TYPE) 3249 { 3250 error ("non-lvalue array in conditional expression"); 3251 return error_mark_node; 3252 } 3253 3254 /* Quickly detect the usual case where op1 and op2 have the same type 3255 after promotion. */ 3256 if (TYPE_MAIN_VARIANT (type1) == TYPE_MAIN_VARIANT (type2)) 3257 { 3258 if (type1 == type2) 3259 result_type = type1; 3260 else 3261 result_type = TYPE_MAIN_VARIANT (type1); 3262 } 3263 else if ((code1 == INTEGER_TYPE || code1 == REAL_TYPE 3264 || code1 == COMPLEX_TYPE) 3265 && (code2 == INTEGER_TYPE || code2 == REAL_TYPE 3266 || code2 == COMPLEX_TYPE)) 3267 { 3268 result_type = c_common_type (type1, type2); 3269 3270 /* If -Wsign-compare, warn here if type1 and type2 have 3271 different signedness. We'll promote the signed to unsigned 3272 and later code won't know it used to be different. 3273 Do this check on the original types, so that explicit casts 3274 will be considered, but default promotions won't. */ 3275 if (warn_sign_compare && !skip_evaluation) 3276 { 3277 int unsigned_op1 = TYPE_UNSIGNED (TREE_TYPE (orig_op1)); 3278 int unsigned_op2 = TYPE_UNSIGNED (TREE_TYPE (orig_op2)); 3279 3280 if (unsigned_op1 ^ unsigned_op2) 3281 { 3282 bool ovf; 3283 3284 /* Do not warn if the result type is signed, since the 3285 signed type will only be chosen if it can represent 3286 all the values of the unsigned type. */ 3287 if (!TYPE_UNSIGNED (result_type)) 3288 /* OK */; 3289 /* Do not warn if the signed quantity is an unsuffixed 3290 integer literal (or some static constant expression 3291 involving such literals) and it is non-negative. */ 3292 else if ((unsigned_op2 3293 && tree_expr_nonnegative_warnv_p (op1, &ovf)) 3294 || (unsigned_op1 3295 && tree_expr_nonnegative_warnv_p (op2, &ovf))) 3296 /* OK */; 3297 else 3298 warning (0, "signed and unsigned type in conditional expression"); 3299 } 3300 } 3301 } 3302 else if (code1 == VOID_TYPE || code2 == VOID_TYPE) 3303 { 3304 if (pedantic && (code1 != VOID_TYPE || code2 != VOID_TYPE)) 3305 pedwarn ("ISO C forbids conditional expr with only one void side"); 3306 result_type = void_type_node; 3307 } 3308 else if (code1 == POINTER_TYPE && code2 == POINTER_TYPE) 3309 { 3310 if (comp_target_types (type1, type2)) 3311 result_type = common_pointer_type (type1, type2); 3312 else if (null_pointer_constant_p (orig_op1)) 3313 result_type = qualify_type (type2, type1); 3314 else if (null_pointer_constant_p (orig_op2)) 3315 result_type = qualify_type (type1, type2); 3316 else if (VOID_TYPE_P (TREE_TYPE (type1))) 3317 { 3318 if (pedantic && TREE_CODE (TREE_TYPE (type2)) == FUNCTION_TYPE) 3319 pedwarn ("ISO C forbids conditional expr between " 3320 "%<void *%> and function pointer"); 3321 result_type = build_pointer_type (qualify_type (TREE_TYPE (type1), 3322 TREE_TYPE (type2))); 3323 } 3324 else if (VOID_TYPE_P (TREE_TYPE (type2))) 3325 { 3326 if (pedantic && TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE) 3327 pedwarn ("ISO C forbids conditional expr between " 3328 "%<void *%> and function pointer"); 3329 result_type = build_pointer_type (qualify_type (TREE_TYPE (type2), 3330 TREE_TYPE (type1))); 3331 } 3332 else 3333 { 3334 pedwarn ("pointer type mismatch in conditional expression"); 3335 result_type = build_pointer_type (void_type_node); 3336 } 3337 } 3338 else if (code1 == POINTER_TYPE && code2 == INTEGER_TYPE) 3339 { 3340 if (!null_pointer_constant_p (orig_op2)) 3341 pedwarn ("pointer/integer type mismatch in conditional expression"); 3342 else 3343 { 3344 op2 = null_pointer_node; 3345 } 3346 result_type = type1; 3347 } 3348 else if (code2 == POINTER_TYPE && code1 == INTEGER_TYPE) 3349 { 3350 if (!null_pointer_constant_p (orig_op1)) 3351 pedwarn ("pointer/integer type mismatch in conditional expression"); 3352 else 3353 { 3354 op1 = null_pointer_node; 3355 } 3356 result_type = type2; 3357 } 3358 3359 if (!result_type) 3360 { 3361 if (flag_cond_mismatch) 3362 result_type = void_type_node; 3363 else 3364 { 3365 error ("type mismatch in conditional expression"); 3366 return error_mark_node; 3367 } 3368 } 3369 3370 /* Merge const and volatile flags of the incoming types. */ 3371 result_type 3372 = build_type_variant (result_type, 3373 TREE_READONLY (op1) || TREE_READONLY (op2), 3374 TREE_THIS_VOLATILE (op1) || TREE_THIS_VOLATILE (op2)); 3375 3376 if (result_type != TREE_TYPE (op1)) 3377 op1 = convert_and_check (result_type, op1); 3378 if (result_type != TREE_TYPE (op2)) 3379 op2 = convert_and_check (result_type, op2); 3380 3381 return fold_build3 (COND_EXPR, result_type, ifexp, op1, op2); 3382} 3383 3384/* Return a compound expression that performs two expressions and 3385 returns the value of the second of them. */ 3386 3387tree 3388build_compound_expr (tree expr1, tree expr2) 3389{ 3390 if (!TREE_SIDE_EFFECTS (expr1)) 3391 { 3392 /* The left-hand operand of a comma expression is like an expression 3393 statement: with -Wextra or -Wunused, we should warn if it doesn't have 3394 any side-effects, unless it was explicitly cast to (void). */ 3395 if (warn_unused_value) 3396 { 3397 if (VOID_TYPE_P (TREE_TYPE (expr1)) 3398 && (TREE_CODE (expr1) == NOP_EXPR 3399 || TREE_CODE (expr1) == CONVERT_EXPR)) 3400 ; /* (void) a, b */ 3401 else if (VOID_TYPE_P (TREE_TYPE (expr1)) 3402 && TREE_CODE (expr1) == COMPOUND_EXPR 3403 && (TREE_CODE (TREE_OPERAND (expr1, 1)) == CONVERT_EXPR 3404 || TREE_CODE (TREE_OPERAND (expr1, 1)) == NOP_EXPR)) 3405 ; /* (void) a, (void) b, c */ 3406 else 3407 warning (0, "left-hand operand of comma expression has no effect"); 3408 } 3409 } 3410 3411 /* With -Wunused, we should also warn if the left-hand operand does have 3412 side-effects, but computes a value which is not used. For example, in 3413 `foo() + bar(), baz()' the result of the `+' operator is not used, 3414 so we should issue a warning. */ 3415 else if (warn_unused_value) 3416 warn_if_unused_value (expr1, input_location); 3417 3418 if (expr2 == error_mark_node) 3419 return error_mark_node; 3420 3421 return build2 (COMPOUND_EXPR, TREE_TYPE (expr2), expr1, expr2); 3422} 3423 3424/* Build an expression representing a cast to type TYPE of expression EXPR. */ 3425 3426tree 3427build_c_cast (tree type, tree expr) 3428{ 3429 tree value = expr; 3430 3431 if (type == error_mark_node || expr == error_mark_node) 3432 return error_mark_node; 3433 3434 /* The ObjC front-end uses TYPE_MAIN_VARIANT to tie together types differing 3435 only in <protocol> qualifications. But when constructing cast expressions, 3436 the protocols do matter and must be kept around. */ 3437 if (objc_is_object_ptr (type) && objc_is_object_ptr (TREE_TYPE (expr))) 3438 return build1 (NOP_EXPR, type, expr); 3439 3440 type = TYPE_MAIN_VARIANT (type); 3441 3442 if (TREE_CODE (type) == ARRAY_TYPE) 3443 { 3444 error ("cast specifies array type"); 3445 return error_mark_node; 3446 } 3447 3448 if (TREE_CODE (type) == FUNCTION_TYPE) 3449 { 3450 error ("cast specifies function type"); 3451 return error_mark_node; 3452 } 3453 3454 if (type == TYPE_MAIN_VARIANT (TREE_TYPE (value))) 3455 { 3456 if (pedantic) 3457 { 3458 if (TREE_CODE (type) == RECORD_TYPE 3459 || TREE_CODE (type) == UNION_TYPE) 3460 pedwarn ("ISO C forbids casting nonscalar to the same type"); 3461 } 3462 } 3463 else if (TREE_CODE (type) == UNION_TYPE) 3464 { 3465 tree field; 3466 3467 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field)) 3468 if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (field)), 3469 TYPE_MAIN_VARIANT (TREE_TYPE (value)))) 3470 break; 3471 3472 if (field) 3473 { 3474 tree t; 3475 3476 if (pedantic) 3477 pedwarn ("ISO C forbids casts to union type"); 3478 t = digest_init (type, 3479 build_constructor_single (type, field, value), 3480 true, 0); 3481 TREE_CONSTANT (t) = TREE_CONSTANT (value); 3482 TREE_INVARIANT (t) = TREE_INVARIANT (value); 3483 return t; 3484 } 3485 error ("cast to union type from type not present in union"); 3486 return error_mark_node; 3487 } 3488 else 3489 { 3490 tree otype, ovalue; 3491 3492 if (type == void_type_node) 3493 return build1 (CONVERT_EXPR, type, value); 3494 3495 otype = TREE_TYPE (value); 3496 3497 /* Optionally warn about potentially worrisome casts. */ 3498 3499 if (warn_cast_qual 3500 && TREE_CODE (type) == POINTER_TYPE 3501 && TREE_CODE (otype) == POINTER_TYPE) 3502 { 3503 tree in_type = type; 3504 tree in_otype = otype; 3505 int added = 0; 3506 int discarded = 0; 3507 3508 /* Check that the qualifiers on IN_TYPE are a superset of 3509 the qualifiers of IN_OTYPE. The outermost level of 3510 POINTER_TYPE nodes is uninteresting and we stop as soon 3511 as we hit a non-POINTER_TYPE node on either type. */ 3512 do 3513 { 3514 in_otype = TREE_TYPE (in_otype); 3515 in_type = TREE_TYPE (in_type); 3516 3517 /* GNU C allows cv-qualified function types. 'const' 3518 means the function is very pure, 'volatile' means it 3519 can't return. We need to warn when such qualifiers 3520 are added, not when they're taken away. */ 3521 if (TREE_CODE (in_otype) == FUNCTION_TYPE 3522 && TREE_CODE (in_type) == FUNCTION_TYPE) 3523 added |= (TYPE_QUALS (in_type) & ~TYPE_QUALS (in_otype)); 3524 else 3525 discarded |= (TYPE_QUALS (in_otype) & ~TYPE_QUALS (in_type)); 3526 } 3527 while (TREE_CODE (in_type) == POINTER_TYPE 3528 && TREE_CODE (in_otype) == POINTER_TYPE); 3529 3530 if (added) 3531 warning (0, "cast adds new qualifiers to function type"); 3532 3533 if (discarded) 3534 /* There are qualifiers present in IN_OTYPE that are not 3535 present in IN_TYPE. */ 3536 warning (0, "cast discards qualifiers from pointer target type"); 3537 } 3538 3539 /* Warn about possible alignment problems. */ 3540 if (STRICT_ALIGNMENT 3541 && TREE_CODE (type) == POINTER_TYPE 3542 && TREE_CODE (otype) == POINTER_TYPE 3543 && TREE_CODE (TREE_TYPE (otype)) != VOID_TYPE 3544 && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE 3545 /* Don't warn about opaque types, where the actual alignment 3546 restriction is unknown. */ 3547 && !((TREE_CODE (TREE_TYPE (otype)) == UNION_TYPE 3548 || TREE_CODE (TREE_TYPE (otype)) == RECORD_TYPE) 3549 && TYPE_MODE (TREE_TYPE (otype)) == VOIDmode) 3550 && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (otype))) 3551 warning (OPT_Wcast_align, 3552 "cast increases required alignment of target type"); 3553 3554 if (TREE_CODE (type) == INTEGER_TYPE 3555 && TREE_CODE (otype) == POINTER_TYPE 3556 && TYPE_PRECISION (type) != TYPE_PRECISION (otype)) 3557 /* Unlike conversion of integers to pointers, where the 3558 warning is disabled for converting constants because 3559 of cases such as SIG_*, warn about converting constant 3560 pointers to integers. In some cases it may cause unwanted 3561 sign extension, and a warning is appropriate. */ 3562 warning (OPT_Wpointer_to_int_cast, 3563 "cast from pointer to integer of different size"); 3564 3565 if (TREE_CODE (value) == CALL_EXPR 3566 && TREE_CODE (type) != TREE_CODE (otype)) 3567 warning (OPT_Wbad_function_cast, "cast from function call of type %qT " 3568 "to non-matching type %qT", otype, type); 3569 3570 if (TREE_CODE (type) == POINTER_TYPE 3571 && TREE_CODE (otype) == INTEGER_TYPE 3572 && TYPE_PRECISION (type) != TYPE_PRECISION (otype) 3573 /* Don't warn about converting any constant. */ 3574 && !TREE_CONSTANT (value)) 3575 warning (OPT_Wint_to_pointer_cast, "cast to pointer from integer " 3576 "of different size"); 3577 3578 if (warn_strict_aliasing <= 2) 3579 strict_aliasing_warning (otype, type, expr); 3580 3581 /* If pedantic, warn for conversions between function and object 3582 pointer types, except for converting a null pointer constant 3583 to function pointer type. */ 3584 if (pedantic 3585 && TREE_CODE (type) == POINTER_TYPE 3586 && TREE_CODE (otype) == POINTER_TYPE 3587 && TREE_CODE (TREE_TYPE (otype)) == FUNCTION_TYPE 3588 && TREE_CODE (TREE_TYPE (type)) != FUNCTION_TYPE) 3589 pedwarn ("ISO C forbids conversion of function pointer to object pointer type"); 3590 3591 if (pedantic 3592 && TREE_CODE (type) == POINTER_TYPE 3593 && TREE_CODE (otype) == POINTER_TYPE 3594 && TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE 3595 && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE 3596 && !null_pointer_constant_p (value)) 3597 pedwarn ("ISO C forbids conversion of object pointer to function pointer type"); 3598 3599 ovalue = value; 3600 value = convert (type, value); 3601 3602 /* Ignore any integer overflow caused by the cast. */ 3603 if (TREE_CODE (value) == INTEGER_CST) 3604 { 3605 if (CONSTANT_CLASS_P (ovalue) 3606 && (TREE_OVERFLOW (ovalue) || TREE_CONSTANT_OVERFLOW (ovalue))) 3607 { 3608 /* Avoid clobbering a shared constant. */ 3609 value = copy_node (value); 3610 TREE_OVERFLOW (value) = TREE_OVERFLOW (ovalue); 3611 TREE_CONSTANT_OVERFLOW (value) = TREE_CONSTANT_OVERFLOW (ovalue); 3612 } 3613 else if (TREE_OVERFLOW (value) || TREE_CONSTANT_OVERFLOW (value)) 3614 /* Reset VALUE's overflow flags, ensuring constant sharing. */ 3615 value = build_int_cst_wide (TREE_TYPE (value), 3616 TREE_INT_CST_LOW (value), 3617 TREE_INT_CST_HIGH (value)); 3618 } 3619 } 3620 3621 /* Don't let a cast be an lvalue. */ 3622 if (value == expr) 3623 value = non_lvalue (value); 3624 3625 return value; 3626} 3627 3628/* Interpret a cast of expression EXPR to type TYPE. */ 3629tree 3630c_cast_expr (struct c_type_name *type_name, tree expr) 3631{ 3632 tree type; 3633 int saved_wsp = warn_strict_prototypes; 3634 3635 /* This avoids warnings about unprototyped casts on 3636 integers. E.g. "#define SIG_DFL (void(*)())0". */ 3637 if (TREE_CODE (expr) == INTEGER_CST) 3638 warn_strict_prototypes = 0; 3639 type = groktypename (type_name); 3640 warn_strict_prototypes = saved_wsp; 3641 3642 return build_c_cast (type, expr); 3643} 3644 3645/* Build an assignment expression of lvalue LHS from value RHS. 3646 MODIFYCODE is the code for a binary operator that we use 3647 to combine the old value of LHS with RHS to get the new value. 3648 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment. */ 3649 3650tree 3651build_modify_expr (tree lhs, enum tree_code modifycode, tree rhs) 3652{ 3653 tree result; 3654 tree newrhs; 3655 tree lhstype = TREE_TYPE (lhs); 3656 tree olhstype = lhstype; 3657 3658 /* Types that aren't fully specified cannot be used in assignments. */ 3659 lhs = require_complete_type (lhs); 3660 3661 /* Avoid duplicate error messages from operands that had errors. */ 3662 if (TREE_CODE (lhs) == ERROR_MARK || TREE_CODE (rhs) == ERROR_MARK) 3663 return error_mark_node; 3664 3665 if (!lvalue_or_else (lhs, lv_assign)) 3666 return error_mark_node; 3667 3668 STRIP_TYPE_NOPS (rhs); 3669 3670 newrhs = rhs; 3671 3672 /* If a binary op has been requested, combine the old LHS value with the RHS 3673 producing the value we should actually store into the LHS. */ 3674 3675 if (modifycode != NOP_EXPR) 3676 { 3677 lhs = stabilize_reference (lhs); 3678 newrhs = build_binary_op (modifycode, lhs, rhs, 1); 3679 } 3680 3681 /* Give an error for storing in something that is 'const'. */ 3682 3683 if (TREE_READONLY (lhs) || TYPE_READONLY (lhstype) 3684 || ((TREE_CODE (lhstype) == RECORD_TYPE 3685 || TREE_CODE (lhstype) == UNION_TYPE) 3686 && C_TYPE_FIELDS_READONLY (lhstype))) 3687 { 3688 readonly_error (lhs, lv_assign); 3689 return error_mark_node; 3690 } 3691 3692 /* If storing into a structure or union member, 3693 it has probably been given type `int'. 3694 Compute the type that would go with 3695 the actual amount of storage the member occupies. */ 3696 3697 if (TREE_CODE (lhs) == COMPONENT_REF 3698 && (TREE_CODE (lhstype) == INTEGER_TYPE 3699 || TREE_CODE (lhstype) == BOOLEAN_TYPE 3700 || TREE_CODE (lhstype) == REAL_TYPE 3701 || TREE_CODE (lhstype) == ENUMERAL_TYPE)) 3702 lhstype = TREE_TYPE (get_unwidened (lhs, 0)); 3703 3704 /* If storing in a field that is in actuality a short or narrower than one, 3705 we must store in the field in its actual type. */ 3706 3707 if (lhstype != TREE_TYPE (lhs)) 3708 { 3709 lhs = copy_node (lhs); 3710 TREE_TYPE (lhs) = lhstype; 3711 } 3712 3713 /* Convert new value to destination type. */ 3714 3715 newrhs = convert_for_assignment (lhstype, newrhs, ic_assign, 3716 NULL_TREE, NULL_TREE, 0); 3717 if (TREE_CODE (newrhs) == ERROR_MARK) 3718 return error_mark_node; 3719 3720 /* Emit ObjC write barrier, if necessary. */ 3721 if (c_dialect_objc () && flag_objc_gc) 3722 { 3723 result = objc_generate_write_barrier (lhs, modifycode, newrhs); 3724 if (result) 3725 return result; 3726 } 3727 3728 /* Scan operands. */ 3729 3730 result = build2 (MODIFY_EXPR, lhstype, lhs, newrhs); 3731 TREE_SIDE_EFFECTS (result) = 1; 3732 3733 /* If we got the LHS in a different type for storing in, 3734 convert the result back to the nominal type of LHS 3735 so that the value we return always has the same type 3736 as the LHS argument. */ 3737 3738 if (olhstype == TREE_TYPE (result)) 3739 return result; 3740 return convert_for_assignment (olhstype, result, ic_assign, 3741 NULL_TREE, NULL_TREE, 0); 3742} 3743 3744/* Convert value RHS to type TYPE as preparation for an assignment 3745 to an lvalue of type TYPE. 3746 The real work of conversion is done by `convert'. 3747 The purpose of this function is to generate error messages 3748 for assignments that are not allowed in C. 3749 ERRTYPE says whether it is argument passing, assignment, 3750 initialization or return. 3751 3752 FUNCTION is a tree for the function being called. 3753 PARMNUM is the number of the argument, for printing in error messages. */ 3754 3755static tree 3756convert_for_assignment (tree type, tree rhs, enum impl_conv errtype, 3757 tree fundecl, tree function, int parmnum) 3758{ 3759 enum tree_code codel = TREE_CODE (type); 3760 tree rhstype; 3761 enum tree_code coder; 3762 tree rname = NULL_TREE; 3763 bool objc_ok = false; 3764 3765 if (errtype == ic_argpass || errtype == ic_argpass_nonproto) 3766 { 3767 tree selector; 3768 /* Change pointer to function to the function itself for 3769 diagnostics. */ 3770 if (TREE_CODE (function) == ADDR_EXPR 3771 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL) 3772 function = TREE_OPERAND (function, 0); 3773 3774 /* Handle an ObjC selector specially for diagnostics. */ 3775 selector = objc_message_selector (); 3776 rname = function; 3777 if (selector && parmnum > 2) 3778 { 3779 rname = selector; 3780 parmnum -= 2; 3781 } 3782 } 3783 3784 /* This macro is used to emit diagnostics to ensure that all format 3785 strings are complete sentences, visible to gettext and checked at 3786 compile time. */ 3787#define WARN_FOR_ASSIGNMENT(AR, AS, IN, RE) \ 3788 do { \ 3789 switch (errtype) \ 3790 { \ 3791 case ic_argpass: \ 3792 pedwarn (AR, parmnum, rname); \ 3793 break; \ 3794 case ic_argpass_nonproto: \ 3795 warning (0, AR, parmnum, rname); \ 3796 break; \ 3797 case ic_assign: \ 3798 pedwarn (AS); \ 3799 break; \ 3800 case ic_init: \ 3801 pedwarn (IN); \ 3802 break; \ 3803 case ic_return: \ 3804 pedwarn (RE); \ 3805 break; \ 3806 default: \ 3807 gcc_unreachable (); \ 3808 } \ 3809 } while (0) 3810 3811 STRIP_TYPE_NOPS (rhs); 3812 3813 if (optimize && TREE_CODE (rhs) == VAR_DECL 3814 && TREE_CODE (TREE_TYPE (rhs)) != ARRAY_TYPE) 3815 rhs = decl_constant_value_for_broken_optimization (rhs); 3816 3817 rhstype = TREE_TYPE (rhs); 3818 coder = TREE_CODE (rhstype); 3819 3820 if (coder == ERROR_MARK) 3821 return error_mark_node; 3822 3823 if (c_dialect_objc ()) 3824 { 3825 int parmno; 3826 3827 switch (errtype) 3828 { 3829 case ic_return: 3830 parmno = 0; 3831 break; 3832 3833 case ic_assign: 3834 parmno = -1; 3835 break; 3836 3837 case ic_init: 3838 parmno = -2; 3839 break; 3840 3841 default: 3842 parmno = parmnum; 3843 break; 3844 } 3845 3846 objc_ok = objc_compare_types (type, rhstype, parmno, rname); 3847 } 3848 3849 if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (rhstype)) 3850 { 3851 overflow_warning (rhs); 3852 return rhs; 3853 } 3854 3855 if (coder == VOID_TYPE) 3856 { 3857 /* Except for passing an argument to an unprototyped function, 3858 this is a constraint violation. When passing an argument to 3859 an unprototyped function, it is compile-time undefined; 3860 making it a constraint in that case was rejected in 3861 DR#252. */ 3862 error ("void value not ignored as it ought to be"); 3863 return error_mark_node; 3864 } 3865 /* A type converts to a reference to it. 3866 This code doesn't fully support references, it's just for the 3867 special case of va_start and va_copy. */ 3868 if (codel == REFERENCE_TYPE 3869 && comptypes (TREE_TYPE (type), TREE_TYPE (rhs)) == 1) 3870 { 3871 if (!lvalue_p (rhs)) 3872 { 3873 error ("cannot pass rvalue to reference parameter"); 3874 return error_mark_node; 3875 } 3876 if (!c_mark_addressable (rhs)) 3877 return error_mark_node; 3878 rhs = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (rhs)), rhs); 3879 3880 /* We already know that these two types are compatible, but they 3881 may not be exactly identical. In fact, `TREE_TYPE (type)' is 3882 likely to be __builtin_va_list and `TREE_TYPE (rhs)' is 3883 likely to be va_list, a typedef to __builtin_va_list, which 3884 is different enough that it will cause problems later. */ 3885 if (TREE_TYPE (TREE_TYPE (rhs)) != TREE_TYPE (type)) 3886 rhs = build1 (NOP_EXPR, build_pointer_type (TREE_TYPE (type)), rhs); 3887 3888 rhs = build1 (NOP_EXPR, type, rhs); 3889 return rhs; 3890 } 3891 /* Some types can interconvert without explicit casts. */ 3892 else if (codel == VECTOR_TYPE && coder == VECTOR_TYPE 3893 && vector_types_convertible_p (type, TREE_TYPE (rhs))) 3894 return convert (type, rhs); 3895 /* Arithmetic types all interconvert, and enum is treated like int. */ 3896 else if ((codel == INTEGER_TYPE || codel == REAL_TYPE 3897 || codel == ENUMERAL_TYPE || codel == COMPLEX_TYPE 3898 || codel == BOOLEAN_TYPE) 3899 && (coder == INTEGER_TYPE || coder == REAL_TYPE 3900 || coder == ENUMERAL_TYPE || coder == COMPLEX_TYPE 3901 || coder == BOOLEAN_TYPE)) 3902 return convert_and_check (type, rhs); 3903 3904 /* Aggregates in different TUs might need conversion. */ 3905 if ((codel == RECORD_TYPE || codel == UNION_TYPE) 3906 && codel == coder 3907 && comptypes (type, rhstype)) 3908 return convert_and_check (type, rhs); 3909 3910 /* Conversion to a transparent union from its member types. 3911 This applies only to function arguments. */ 3912 if (codel == UNION_TYPE && TYPE_TRANSPARENT_UNION (type) 3913 && (errtype == ic_argpass || errtype == ic_argpass_nonproto)) 3914 { 3915 tree memb, marginal_memb = NULL_TREE; 3916 3917 for (memb = TYPE_FIELDS (type); memb ; memb = TREE_CHAIN (memb)) 3918 { 3919 tree memb_type = TREE_TYPE (memb); 3920 3921 if (comptypes (TYPE_MAIN_VARIANT (memb_type), 3922 TYPE_MAIN_VARIANT (rhstype))) 3923 break; 3924 3925 if (TREE_CODE (memb_type) != POINTER_TYPE) 3926 continue; 3927 3928 if (coder == POINTER_TYPE) 3929 { 3930 tree ttl = TREE_TYPE (memb_type); 3931 tree ttr = TREE_TYPE (rhstype); 3932 3933 /* Any non-function converts to a [const][volatile] void * 3934 and vice versa; otherwise, targets must be the same. 3935 Meanwhile, the lhs target must have all the qualifiers of 3936 the rhs. */ 3937 if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr) 3938 || comp_target_types (memb_type, rhstype)) 3939 { 3940 /* If this type won't generate any warnings, use it. */ 3941 if (TYPE_QUALS (ttl) == TYPE_QUALS (ttr) 3942 || ((TREE_CODE (ttr) == FUNCTION_TYPE 3943 && TREE_CODE (ttl) == FUNCTION_TYPE) 3944 ? ((TYPE_QUALS (ttl) | TYPE_QUALS (ttr)) 3945 == TYPE_QUALS (ttr)) 3946 : ((TYPE_QUALS (ttl) | TYPE_QUALS (ttr)) 3947 == TYPE_QUALS (ttl)))) 3948 break; 3949 3950 /* Keep looking for a better type, but remember this one. */ 3951 if (!marginal_memb) 3952 marginal_memb = memb; 3953 } 3954 } 3955 3956 /* Can convert integer zero to any pointer type. */ 3957 if (null_pointer_constant_p (rhs)) 3958 { 3959 rhs = null_pointer_node; 3960 break; 3961 } 3962 } 3963 3964 if (memb || marginal_memb) 3965 { 3966 if (!memb) 3967 { 3968 /* We have only a marginally acceptable member type; 3969 it needs a warning. */ 3970 tree ttl = TREE_TYPE (TREE_TYPE (marginal_memb)); 3971 tree ttr = TREE_TYPE (rhstype); 3972 3973 /* Const and volatile mean something different for function 3974 types, so the usual warnings are not appropriate. */ 3975 if (TREE_CODE (ttr) == FUNCTION_TYPE 3976 && TREE_CODE (ttl) == FUNCTION_TYPE) 3977 { 3978 /* Because const and volatile on functions are 3979 restrictions that say the function will not do 3980 certain things, it is okay to use a const or volatile 3981 function where an ordinary one is wanted, but not 3982 vice-versa. */ 3983 if (TYPE_QUALS (ttl) & ~TYPE_QUALS (ttr)) 3984 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE " 3985 "makes qualified function " 3986 "pointer from unqualified"), 3987 G_("assignment makes qualified " 3988 "function pointer from " 3989 "unqualified"), 3990 G_("initialization makes qualified " 3991 "function pointer from " 3992 "unqualified"), 3993 G_("return makes qualified function " 3994 "pointer from unqualified")); 3995 } 3996 else if (TYPE_QUALS (ttr) & ~TYPE_QUALS (ttl)) 3997 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE discards " 3998 "qualifiers from pointer target type"), 3999 G_("assignment discards qualifiers " 4000 "from pointer target type"), 4001 G_("initialization discards qualifiers " 4002 "from pointer target type"), 4003 G_("return discards qualifiers from " 4004 "pointer target type")); 4005 4006 memb = marginal_memb; 4007 } 4008 4009 if (pedantic && (!fundecl || !DECL_IN_SYSTEM_HEADER (fundecl))) 4010 pedwarn ("ISO C prohibits argument conversion to union type"); 4011 4012 return build_constructor_single (type, memb, rhs); 4013 } 4014 } 4015 4016 /* Conversions among pointers */ 4017 else if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE) 4018 && (coder == codel)) 4019 { 4020 tree ttl = TREE_TYPE (type); 4021 tree ttr = TREE_TYPE (rhstype); 4022 tree mvl = ttl; 4023 tree mvr = ttr; 4024 bool is_opaque_pointer; 4025 int target_cmp = 0; /* Cache comp_target_types () result. */ 4026 4027 if (TREE_CODE (mvl) != ARRAY_TYPE) 4028 mvl = TYPE_MAIN_VARIANT (mvl); 4029 if (TREE_CODE (mvr) != ARRAY_TYPE) 4030 mvr = TYPE_MAIN_VARIANT (mvr); 4031 /* Opaque pointers are treated like void pointers. */ 4032 is_opaque_pointer = (targetm.vector_opaque_p (type) 4033 || targetm.vector_opaque_p (rhstype)) 4034 && TREE_CODE (ttl) == VECTOR_TYPE 4035 && TREE_CODE (ttr) == VECTOR_TYPE; 4036 4037 /* C++ does not allow the implicit conversion void* -> T*. However, 4038 for the purpose of reducing the number of false positives, we 4039 tolerate the special case of 4040 4041 int *p = NULL; 4042 4043 where NULL is typically defined in C to be '(void *) 0'. */ 4044 if (VOID_TYPE_P (ttr) && rhs != null_pointer_node && !VOID_TYPE_P (ttl)) 4045 warning (OPT_Wc___compat, "request for implicit conversion from " 4046 "%qT to %qT not permitted in C++", rhstype, type); 4047 4048 /* Check if the right-hand side has a format attribute but the 4049 left-hand side doesn't. */ 4050 if (warn_missing_format_attribute 4051 && check_missing_format_attribute (type, rhstype)) 4052 { 4053 switch (errtype) 4054 { 4055 case ic_argpass: 4056 case ic_argpass_nonproto: 4057 warning (OPT_Wmissing_format_attribute, 4058 "argument %d of %qE might be " 4059 "a candidate for a format attribute", 4060 parmnum, rname); 4061 break; 4062 case ic_assign: 4063 warning (OPT_Wmissing_format_attribute, 4064 "assignment left-hand side might be " 4065 "a candidate for a format attribute"); 4066 break; 4067 case ic_init: 4068 warning (OPT_Wmissing_format_attribute, 4069 "initialization left-hand side might be " 4070 "a candidate for a format attribute"); 4071 break; 4072 case ic_return: 4073 warning (OPT_Wmissing_format_attribute, 4074 "return type might be " 4075 "a candidate for a format attribute"); 4076 break; 4077 default: 4078 gcc_unreachable (); 4079 } 4080 } 4081 4082 /* Any non-function converts to a [const][volatile] void * 4083 and vice versa; otherwise, targets must be the same. 4084 Meanwhile, the lhs target must have all the qualifiers of the rhs. */ 4085 if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr) 4086 || (target_cmp = comp_target_types (type, rhstype)) 4087 || is_opaque_pointer 4088 || (c_common_unsigned_type (mvl) 4089 == c_common_unsigned_type (mvr))) 4090 { 4091 if (pedantic 4092 && ((VOID_TYPE_P (ttl) && TREE_CODE (ttr) == FUNCTION_TYPE) 4093 || 4094 (VOID_TYPE_P (ttr) 4095 && !null_pointer_constant_p (rhs) 4096 && TREE_CODE (ttl) == FUNCTION_TYPE))) 4097 WARN_FOR_ASSIGNMENT (G_("ISO C forbids passing argument %d of " 4098 "%qE between function pointer " 4099 "and %<void *%>"), 4100 G_("ISO C forbids assignment between " 4101 "function pointer and %<void *%>"), 4102 G_("ISO C forbids initialization between " 4103 "function pointer and %<void *%>"), 4104 G_("ISO C forbids return between function " 4105 "pointer and %<void *%>")); 4106 /* Const and volatile mean something different for function types, 4107 so the usual warnings are not appropriate. */ 4108 else if (TREE_CODE (ttr) != FUNCTION_TYPE 4109 && TREE_CODE (ttl) != FUNCTION_TYPE) 4110 { 4111 if (TYPE_QUALS (ttr) & ~TYPE_QUALS (ttl)) 4112 { 4113 /* Types differing only by the presence of the 'volatile' 4114 qualifier are acceptable if the 'volatile' has been added 4115 in by the Objective-C EH machinery. */ 4116 if (!objc_type_quals_match (ttl, ttr)) 4117 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE discards " 4118 "qualifiers from pointer target type"), 4119 G_("assignment discards qualifiers " 4120 "from pointer target type"), 4121 G_("initialization discards qualifiers " 4122 "from pointer target type"), 4123 G_("return discards qualifiers from " 4124 "pointer target type")); 4125 } 4126 /* If this is not a case of ignoring a mismatch in signedness, 4127 no warning. */ 4128 else if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr) 4129 || target_cmp) 4130 ; 4131 /* If there is a mismatch, do warn. */ 4132 else if (warn_pointer_sign) 4133 WARN_FOR_ASSIGNMENT (G_("pointer targets in passing argument " 4134 "%d of %qE differ in signedness"), 4135 G_("pointer targets in assignment " 4136 "differ in signedness"), 4137 G_("pointer targets in initialization " 4138 "differ in signedness"), 4139 G_("pointer targets in return differ " 4140 "in signedness")); 4141 } 4142 else if (TREE_CODE (ttl) == FUNCTION_TYPE 4143 && TREE_CODE (ttr) == FUNCTION_TYPE) 4144 { 4145 /* Because const and volatile on functions are restrictions 4146 that say the function will not do certain things, 4147 it is okay to use a const or volatile function 4148 where an ordinary one is wanted, but not vice-versa. */ 4149 if (TYPE_QUALS (ttl) & ~TYPE_QUALS (ttr)) 4150 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE makes " 4151 "qualified function pointer " 4152 "from unqualified"), 4153 G_("assignment makes qualified function " 4154 "pointer from unqualified"), 4155 G_("initialization makes qualified " 4156 "function pointer from unqualified"), 4157 G_("return makes qualified function " 4158 "pointer from unqualified")); 4159 } 4160 } 4161 else 4162 /* Avoid warning about the volatile ObjC EH puts on decls. */ 4163 if (!objc_ok) 4164 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE from " 4165 "incompatible pointer type"), 4166 G_("assignment from incompatible pointer type"), 4167 G_("initialization from incompatible " 4168 "pointer type"), 4169 G_("return from incompatible pointer type")); 4170 4171 return convert (type, rhs); 4172 } 4173 else if (codel == POINTER_TYPE && coder == ARRAY_TYPE) 4174 { 4175 /* ??? This should not be an error when inlining calls to 4176 unprototyped functions. */ 4177 error ("invalid use of non-lvalue array"); 4178 return error_mark_node; 4179 } 4180 else if (codel == POINTER_TYPE && coder == INTEGER_TYPE) 4181 { 4182 /* An explicit constant 0 can convert to a pointer, 4183 or one that results from arithmetic, even including 4184 a cast to integer type. */ 4185 if (!null_pointer_constant_p (rhs)) 4186 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE makes " 4187 "pointer from integer without a cast"), 4188 G_("assignment makes pointer from integer " 4189 "without a cast"), 4190 G_("initialization makes pointer from " 4191 "integer without a cast"), 4192 G_("return makes pointer from integer " 4193 "without a cast")); 4194 4195 return convert (type, rhs); 4196 } 4197 else if (codel == INTEGER_TYPE && coder == POINTER_TYPE) 4198 { 4199 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE makes integer " 4200 "from pointer without a cast"), 4201 G_("assignment makes integer from pointer " 4202 "without a cast"), 4203 G_("initialization makes integer from pointer " 4204 "without a cast"), 4205 G_("return makes integer from pointer " 4206 "without a cast")); 4207 return convert (type, rhs); 4208 } 4209 else if (codel == BOOLEAN_TYPE && coder == POINTER_TYPE) 4210 return convert (type, rhs); 4211 4212 switch (errtype) 4213 { 4214 case ic_argpass: 4215 case ic_argpass_nonproto: 4216 /* ??? This should not be an error when inlining calls to 4217 unprototyped functions. */ 4218 error ("incompatible type for argument %d of %qE", parmnum, rname); 4219 break; 4220 case ic_assign: 4221 error ("incompatible types in assignment"); 4222 break; 4223 case ic_init: 4224 error ("incompatible types in initialization"); 4225 break; 4226 case ic_return: 4227 error ("incompatible types in return"); 4228 break; 4229 default: 4230 gcc_unreachable (); 4231 } 4232 4233 return error_mark_node; 4234} 4235 4236/* Convert VALUE for assignment into inlined parameter PARM. ARGNUM 4237 is used for error and warning reporting and indicates which argument 4238 is being processed. */ 4239 4240tree 4241c_convert_parm_for_inlining (tree parm, tree value, tree fn, int argnum) 4242{ 4243 tree ret, type; 4244 4245 /* If FN was prototyped at the call site, the value has been converted 4246 already in convert_arguments. 4247 However, we might see a prototype now that was not in place when 4248 the function call was seen, so check that the VALUE actually matches 4249 PARM before taking an early exit. */ 4250 if (!value 4251 || (TYPE_ARG_TYPES (TREE_TYPE (fn)) 4252 && (TYPE_MAIN_VARIANT (TREE_TYPE (parm)) 4253 == TYPE_MAIN_VARIANT (TREE_TYPE (value))))) 4254 return value; 4255 4256 type = TREE_TYPE (parm); 4257 ret = convert_for_assignment (type, value, 4258 ic_argpass_nonproto, fn, 4259 fn, argnum); 4260 if (targetm.calls.promote_prototypes (TREE_TYPE (fn)) 4261 && INTEGRAL_TYPE_P (type) 4262 && (TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node))) 4263 ret = default_conversion (ret); 4264 return ret; 4265} 4266 4267/* If VALUE is a compound expr all of whose expressions are constant, then 4268 return its value. Otherwise, return error_mark_node. 4269 4270 This is for handling COMPOUND_EXPRs as initializer elements 4271 which is allowed with a warning when -pedantic is specified. */ 4272 4273static tree 4274valid_compound_expr_initializer (tree value, tree endtype) 4275{ 4276 if (TREE_CODE (value) == COMPOUND_EXPR) 4277 { 4278 if (valid_compound_expr_initializer (TREE_OPERAND (value, 0), endtype) 4279 == error_mark_node) 4280 return error_mark_node; 4281 return valid_compound_expr_initializer (TREE_OPERAND (value, 1), 4282 endtype); 4283 } 4284 else if (!initializer_constant_valid_p (value, endtype)) 4285 return error_mark_node; 4286 else 4287 return value; 4288} 4289 4290/* Perform appropriate conversions on the initial value of a variable, 4291 store it in the declaration DECL, 4292 and print any error messages that are appropriate. 4293 If the init is invalid, store an ERROR_MARK. */ 4294 4295void 4296store_init_value (tree decl, tree init) 4297{ 4298 tree value, type; 4299 4300 /* If variable's type was invalidly declared, just ignore it. */ 4301 4302 type = TREE_TYPE (decl); 4303 if (TREE_CODE (type) == ERROR_MARK) 4304 return; 4305 4306 /* Digest the specified initializer into an expression. */ 4307 4308 value = digest_init (type, init, true, TREE_STATIC (decl)); 4309 4310 /* Store the expression if valid; else report error. */ 4311 4312 if (!in_system_header 4313 && AGGREGATE_TYPE_P (TREE_TYPE (decl)) && !TREE_STATIC (decl)) 4314 warning (OPT_Wtraditional, "traditional C rejects automatic " 4315 "aggregate initialization"); 4316 4317 DECL_INITIAL (decl) = value; 4318 4319 /* ANSI wants warnings about out-of-range constant initializers. */ 4320 STRIP_TYPE_NOPS (value); 4321 constant_expression_warning (value); 4322 4323 /* Check if we need to set array size from compound literal size. */ 4324 if (TREE_CODE (type) == ARRAY_TYPE 4325 && TYPE_DOMAIN (type) == 0 4326 && value != error_mark_node) 4327 { 4328 tree inside_init = init; 4329 4330 STRIP_TYPE_NOPS (inside_init); 4331 inside_init = fold (inside_init); 4332 4333 if (TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR) 4334 { 4335 tree cldecl = COMPOUND_LITERAL_EXPR_DECL (inside_init); 4336 4337 if (TYPE_DOMAIN (TREE_TYPE (cldecl))) 4338 { 4339 /* For int foo[] = (int [3]){1}; we need to set array size 4340 now since later on array initializer will be just the 4341 brace enclosed list of the compound literal. */ 4342 type = build_distinct_type_copy (TYPE_MAIN_VARIANT (type)); 4343 TREE_TYPE (decl) = type; 4344 TYPE_DOMAIN (type) = TYPE_DOMAIN (TREE_TYPE (cldecl)); 4345 layout_type (type); 4346 layout_decl (cldecl, 0); 4347 } 4348 } 4349 } 4350} 4351 4352/* Methods for storing and printing names for error messages. */ 4353 4354/* Implement a spelling stack that allows components of a name to be pushed 4355 and popped. Each element on the stack is this structure. */ 4356 4357struct spelling 4358{ 4359 int kind; 4360 union 4361 { 4362 unsigned HOST_WIDE_INT i; 4363 const char *s; 4364 } u; 4365}; 4366 4367#define SPELLING_STRING 1 4368#define SPELLING_MEMBER 2 4369#define SPELLING_BOUNDS 3 4370 4371static struct spelling *spelling; /* Next stack element (unused). */ 4372static struct spelling *spelling_base; /* Spelling stack base. */ 4373static int spelling_size; /* Size of the spelling stack. */ 4374 4375/* Macros to save and restore the spelling stack around push_... functions. 4376 Alternative to SAVE_SPELLING_STACK. */ 4377 4378#define SPELLING_DEPTH() (spelling - spelling_base) 4379#define RESTORE_SPELLING_DEPTH(DEPTH) (spelling = spelling_base + (DEPTH)) 4380 4381/* Push an element on the spelling stack with type KIND and assign VALUE 4382 to MEMBER. */ 4383 4384#define PUSH_SPELLING(KIND, VALUE, MEMBER) \ 4385{ \ 4386 int depth = SPELLING_DEPTH (); \ 4387 \ 4388 if (depth >= spelling_size) \ 4389 { \ 4390 spelling_size += 10; \ 4391 spelling_base = XRESIZEVEC (struct spelling, spelling_base, \ 4392 spelling_size); \ 4393 RESTORE_SPELLING_DEPTH (depth); \ 4394 } \ 4395 \ 4396 spelling->kind = (KIND); \ 4397 spelling->MEMBER = (VALUE); \ 4398 spelling++; \ 4399} 4400 4401/* Push STRING on the stack. Printed literally. */ 4402 4403static void 4404push_string (const char *string) 4405{ 4406 PUSH_SPELLING (SPELLING_STRING, string, u.s); 4407} 4408 4409/* Push a member name on the stack. Printed as '.' STRING. */ 4410 4411static void 4412push_member_name (tree decl) 4413{ 4414 const char *const string 4415 = DECL_NAME (decl) ? IDENTIFIER_POINTER (DECL_NAME (decl)) : "<anonymous>"; 4416 PUSH_SPELLING (SPELLING_MEMBER, string, u.s); 4417} 4418 4419/* Push an array bounds on the stack. Printed as [BOUNDS]. */ 4420 4421static void 4422push_array_bounds (unsigned HOST_WIDE_INT bounds) 4423{ 4424 PUSH_SPELLING (SPELLING_BOUNDS, bounds, u.i); 4425} 4426 4427/* Compute the maximum size in bytes of the printed spelling. */ 4428 4429static int 4430spelling_length (void) 4431{ 4432 int size = 0; 4433 struct spelling *p; 4434 4435 for (p = spelling_base; p < spelling; p++) 4436 { 4437 if (p->kind == SPELLING_BOUNDS) 4438 size += 25; 4439 else 4440 size += strlen (p->u.s) + 1; 4441 } 4442 4443 return size; 4444} 4445 4446/* Print the spelling to BUFFER and return it. */ 4447 4448static char * 4449print_spelling (char *buffer) 4450{ 4451 char *d = buffer; 4452 struct spelling *p; 4453 4454 for (p = spelling_base; p < spelling; p++) 4455 if (p->kind == SPELLING_BOUNDS) 4456 { 4457 sprintf (d, "[" HOST_WIDE_INT_PRINT_UNSIGNED "]", p->u.i); 4458 d += strlen (d); 4459 } 4460 else 4461 { 4462 const char *s; 4463 if (p->kind == SPELLING_MEMBER) 4464 *d++ = '.'; 4465 for (s = p->u.s; (*d = *s++); d++) 4466 ; 4467 } 4468 *d++ = '\0'; 4469 return buffer; 4470} 4471 4472/* Issue an error message for a bad initializer component. 4473 MSGID identifies the message. 4474 The component name is taken from the spelling stack. */ 4475 4476void 4477error_init (const char *msgid) 4478{ 4479 char *ofwhat; 4480 4481 error ("%s", _(msgid)); 4482 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1)); 4483 if (*ofwhat) 4484 error ("(near initialization for %qs)", ofwhat); 4485} 4486 4487/* Issue a pedantic warning for a bad initializer component. 4488 MSGID identifies the message. 4489 The component name is taken from the spelling stack. */ 4490 4491void 4492pedwarn_init (const char *msgid) 4493{ 4494 char *ofwhat; 4495 4496 pedwarn ("%s", _(msgid)); 4497 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1)); 4498 if (*ofwhat) 4499 pedwarn ("(near initialization for %qs)", ofwhat); 4500} 4501 4502/* Issue a warning for a bad initializer component. 4503 MSGID identifies the message. 4504 The component name is taken from the spelling stack. */ 4505 4506static void 4507warning_init (const char *msgid) 4508{ 4509 char *ofwhat; 4510 4511 warning (0, "%s", _(msgid)); 4512 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1)); 4513 if (*ofwhat) 4514 warning (0, "(near initialization for %qs)", ofwhat); 4515} 4516 4517/* If TYPE is an array type and EXPR is a parenthesized string 4518 constant, warn if pedantic that EXPR is being used to initialize an 4519 object of type TYPE. */ 4520 4521void 4522maybe_warn_string_init (tree type, struct c_expr expr) 4523{ 4524 if (pedantic 4525 && TREE_CODE (type) == ARRAY_TYPE 4526 && TREE_CODE (expr.value) == STRING_CST 4527 && expr.original_code != STRING_CST) 4528 pedwarn_init ("array initialized from parenthesized string constant"); 4529} 4530 4531/* Digest the parser output INIT as an initializer for type TYPE. 4532 Return a C expression of type TYPE to represent the initial value. 4533 4534 If INIT is a string constant, STRICT_STRING is true if it is 4535 unparenthesized or we should not warn here for it being parenthesized. 4536 For other types of INIT, STRICT_STRING is not used. 4537 4538 REQUIRE_CONSTANT requests an error if non-constant initializers or 4539 elements are seen. */ 4540 4541static tree 4542digest_init (tree type, tree init, bool strict_string, int require_constant) 4543{ 4544 enum tree_code code = TREE_CODE (type); 4545 tree inside_init = init; 4546 4547 if (type == error_mark_node 4548 || !init 4549 || init == error_mark_node 4550 || TREE_TYPE (init) == error_mark_node) 4551 return error_mark_node; 4552 4553 STRIP_TYPE_NOPS (inside_init); 4554 4555 inside_init = fold (inside_init); 4556 4557 /* Initialization of an array of chars from a string constant 4558 optionally enclosed in braces. */ 4559 4560 if (code == ARRAY_TYPE && inside_init 4561 && TREE_CODE (inside_init) == STRING_CST) 4562 { 4563 tree typ1 = TYPE_MAIN_VARIANT (TREE_TYPE (type)); 4564 /* Note that an array could be both an array of character type 4565 and an array of wchar_t if wchar_t is signed char or unsigned 4566 char. */ 4567 bool char_array = (typ1 == char_type_node 4568 || typ1 == signed_char_type_node 4569 || typ1 == unsigned_char_type_node); 4570 bool wchar_array = !!comptypes (typ1, wchar_type_node); 4571 if (char_array || wchar_array) 4572 { 4573 struct c_expr expr; 4574 bool char_string; 4575 expr.value = inside_init; 4576 expr.original_code = (strict_string ? STRING_CST : ERROR_MARK); 4577 maybe_warn_string_init (type, expr); 4578 4579 char_string 4580 = (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (inside_init))) 4581 == char_type_node); 4582 4583 if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)), 4584 TYPE_MAIN_VARIANT (type))) 4585 return inside_init; 4586 4587 if (!wchar_array && !char_string) 4588 { 4589 error_init ("char-array initialized from wide string"); 4590 return error_mark_node; 4591 } 4592 if (char_string && !char_array) 4593 { 4594 error_init ("wchar_t-array initialized from non-wide string"); 4595 return error_mark_node; 4596 } 4597 4598 TREE_TYPE (inside_init) = type; 4599 if (TYPE_DOMAIN (type) != 0 4600 && TYPE_SIZE (type) != 0 4601 && TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST 4602 /* Subtract 1 (or sizeof (wchar_t)) 4603 because it's ok to ignore the terminating null char 4604 that is counted in the length of the constant. */ 4605 && 0 > compare_tree_int (TYPE_SIZE_UNIT (type), 4606 TREE_STRING_LENGTH (inside_init) 4607 - ((TYPE_PRECISION (typ1) 4608 != TYPE_PRECISION (char_type_node)) 4609 ? (TYPE_PRECISION (wchar_type_node) 4610 / BITS_PER_UNIT) 4611 : 1))) 4612 pedwarn_init ("initializer-string for array of chars is too long"); 4613 4614 return inside_init; 4615 } 4616 else if (INTEGRAL_TYPE_P (typ1)) 4617 { 4618 error_init ("array of inappropriate type initialized " 4619 "from string constant"); 4620 return error_mark_node; 4621 } 4622 } 4623 4624 /* Build a VECTOR_CST from a *constant* vector constructor. If the 4625 vector constructor is not constant (e.g. {1,2,3,foo()}) then punt 4626 below and handle as a constructor. */ 4627 if (code == VECTOR_TYPE 4628 && TREE_CODE (TREE_TYPE (inside_init)) == VECTOR_TYPE 4629 && vector_types_convertible_p (TREE_TYPE (inside_init), type) 4630 && TREE_CONSTANT (inside_init)) 4631 { 4632 if (TREE_CODE (inside_init) == VECTOR_CST 4633 && comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)), 4634 TYPE_MAIN_VARIANT (type))) 4635 return inside_init; 4636 4637 if (TREE_CODE (inside_init) == CONSTRUCTOR) 4638 { 4639 unsigned HOST_WIDE_INT ix; 4640 tree value; 4641 bool constant_p = true; 4642 4643 /* Iterate through elements and check if all constructor 4644 elements are *_CSTs. */ 4645 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (inside_init), ix, value) 4646 if (!CONSTANT_CLASS_P (value)) 4647 { 4648 constant_p = false; 4649 break; 4650 } 4651 4652 if (constant_p) 4653 return build_vector_from_ctor (type, 4654 CONSTRUCTOR_ELTS (inside_init)); 4655 } 4656 } 4657 4658 /* Any type can be initialized 4659 from an expression of the same type, optionally with braces. */ 4660 4661 if (inside_init && TREE_TYPE (inside_init) != 0 4662 && (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)), 4663 TYPE_MAIN_VARIANT (type)) 4664 || (code == ARRAY_TYPE 4665 && comptypes (TREE_TYPE (inside_init), type)) 4666 || (code == VECTOR_TYPE 4667 && comptypes (TREE_TYPE (inside_init), type)) 4668 || (code == POINTER_TYPE 4669 && TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE 4670 && comptypes (TREE_TYPE (TREE_TYPE (inside_init)), 4671 TREE_TYPE (type))))) 4672 { 4673 if (code == POINTER_TYPE) 4674 { 4675 if (TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE) 4676 { 4677 if (TREE_CODE (inside_init) == STRING_CST 4678 || TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR) 4679 inside_init = array_to_pointer_conversion (inside_init); 4680 else 4681 { 4682 error_init ("invalid use of non-lvalue array"); 4683 return error_mark_node; 4684 } 4685 } 4686 } 4687 4688 if (code == VECTOR_TYPE) 4689 /* Although the types are compatible, we may require a 4690 conversion. */ 4691 inside_init = convert (type, inside_init); 4692 4693 if (require_constant 4694 && (code == VECTOR_TYPE || !flag_isoc99) 4695 && TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR) 4696 { 4697 /* As an extension, allow initializing objects with static storage 4698 duration with compound literals (which are then treated just as 4699 the brace enclosed list they contain). Also allow this for 4700 vectors, as we can only assign them with compound literals. */ 4701 tree decl = COMPOUND_LITERAL_EXPR_DECL (inside_init); 4702 inside_init = DECL_INITIAL (decl); 4703 } 4704 4705 if (code == ARRAY_TYPE && TREE_CODE (inside_init) != STRING_CST 4706 && TREE_CODE (inside_init) != CONSTRUCTOR) 4707 { 4708 error_init ("array initialized from non-constant array expression"); 4709 return error_mark_node; 4710 } 4711 4712 if (optimize && TREE_CODE (inside_init) == VAR_DECL) 4713 inside_init = decl_constant_value_for_broken_optimization (inside_init); 4714 4715 /* Compound expressions can only occur here if -pedantic or 4716 -pedantic-errors is specified. In the later case, we always want 4717 an error. In the former case, we simply want a warning. */ 4718 if (require_constant && pedantic 4719 && TREE_CODE (inside_init) == COMPOUND_EXPR) 4720 { 4721 inside_init 4722 = valid_compound_expr_initializer (inside_init, 4723 TREE_TYPE (inside_init)); 4724 if (inside_init == error_mark_node) 4725 error_init ("initializer element is not constant"); 4726 else 4727 pedwarn_init ("initializer element is not constant"); 4728 if (flag_pedantic_errors) 4729 inside_init = error_mark_node; 4730 } 4731 else if (require_constant 4732 && !initializer_constant_valid_p (inside_init, 4733 TREE_TYPE (inside_init))) 4734 { 4735 error_init ("initializer element is not constant"); 4736 inside_init = error_mark_node; 4737 } 4738 4739 /* Added to enable additional -Wmissing-format-attribute warnings. */ 4740 if (TREE_CODE (TREE_TYPE (inside_init)) == POINTER_TYPE) 4741 inside_init = convert_for_assignment (type, inside_init, ic_init, NULL_TREE, 4742 NULL_TREE, 0); 4743 return inside_init; 4744 } 4745 4746 /* Handle scalar types, including conversions. */ 4747 4748 if (code == INTEGER_TYPE || code == REAL_TYPE || code == POINTER_TYPE 4749 || code == ENUMERAL_TYPE || code == BOOLEAN_TYPE || code == COMPLEX_TYPE 4750 || code == VECTOR_TYPE) 4751 { 4752 if (TREE_CODE (TREE_TYPE (init)) == ARRAY_TYPE 4753 && (TREE_CODE (init) == STRING_CST 4754 || TREE_CODE (init) == COMPOUND_LITERAL_EXPR)) 4755 init = array_to_pointer_conversion (init); 4756 inside_init 4757 = convert_for_assignment (type, init, ic_init, 4758 NULL_TREE, NULL_TREE, 0); 4759 4760 /* Check to see if we have already given an error message. */ 4761 if (inside_init == error_mark_node) 4762 ; 4763 else if (require_constant && !TREE_CONSTANT (inside_init)) 4764 { 4765 error_init ("initializer element is not constant"); 4766 inside_init = error_mark_node; 4767 } 4768 else if (require_constant 4769 && !initializer_constant_valid_p (inside_init, 4770 TREE_TYPE (inside_init))) 4771 { 4772 error_init ("initializer element is not computable at load time"); 4773 inside_init = error_mark_node; 4774 } 4775 4776 return inside_init; 4777 } 4778 4779 /* Come here only for records and arrays. */ 4780 4781 if (COMPLETE_TYPE_P (type) && TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST) 4782 { 4783 error_init ("variable-sized object may not be initialized"); 4784 return error_mark_node; 4785 } 4786 4787 error_init ("invalid initializer"); 4788 return error_mark_node; 4789} 4790 4791/* Handle initializers that use braces. */ 4792 4793/* Type of object we are accumulating a constructor for. 4794 This type is always a RECORD_TYPE, UNION_TYPE or ARRAY_TYPE. */ 4795static tree constructor_type; 4796 4797/* For a RECORD_TYPE or UNION_TYPE, this is the chain of fields 4798 left to fill. */ 4799static tree constructor_fields; 4800 4801/* For an ARRAY_TYPE, this is the specified index 4802 at which to store the next element we get. */ 4803static tree constructor_index; 4804 4805/* For an ARRAY_TYPE, this is the maximum index. */ 4806static tree constructor_max_index; 4807 4808/* For a RECORD_TYPE, this is the first field not yet written out. */ 4809static tree constructor_unfilled_fields; 4810 4811/* For an ARRAY_TYPE, this is the index of the first element 4812 not yet written out. */ 4813static tree constructor_unfilled_index; 4814 4815/* In a RECORD_TYPE, the byte index of the next consecutive field. 4816 This is so we can generate gaps between fields, when appropriate. */ 4817static tree constructor_bit_index; 4818 4819/* If we are saving up the elements rather than allocating them, 4820 this is the list of elements so far (in reverse order, 4821 most recent first). */ 4822static VEC(constructor_elt,gc) *constructor_elements; 4823 4824/* 1 if constructor should be incrementally stored into a constructor chain, 4825 0 if all the elements should be kept in AVL tree. */ 4826static int constructor_incremental; 4827 4828/* 1 if so far this constructor's elements are all compile-time constants. */ 4829static int constructor_constant; 4830 4831/* 1 if so far this constructor's elements are all valid address constants. */ 4832static int constructor_simple; 4833 4834/* 1 if this constructor is erroneous so far. */ 4835static int constructor_erroneous; 4836 4837/* Structure for managing pending initializer elements, organized as an 4838 AVL tree. */ 4839 4840struct init_node 4841{ 4842 struct init_node *left, *right; 4843 struct init_node *parent; 4844 int balance; 4845 tree purpose; 4846 tree value; 4847}; 4848 4849/* Tree of pending elements at this constructor level. 4850 These are elements encountered out of order 4851 which belong at places we haven't reached yet in actually 4852 writing the output. 4853 Will never hold tree nodes across GC runs. */ 4854static struct init_node *constructor_pending_elts; 4855 4856/* The SPELLING_DEPTH of this constructor. */ 4857static int constructor_depth; 4858 4859/* DECL node for which an initializer is being read. 4860 0 means we are reading a constructor expression 4861 such as (struct foo) {...}. */ 4862static tree constructor_decl; 4863 4864/* Nonzero if this is an initializer for a top-level decl. */ 4865static int constructor_top_level; 4866 4867/* Nonzero if there were any member designators in this initializer. */ 4868static int constructor_designated; 4869 4870/* Nesting depth of designator list. */ 4871static int designator_depth; 4872 4873/* Nonzero if there were diagnosed errors in this designator list. */ 4874static int designator_erroneous; 4875 4876 4877/* This stack has a level for each implicit or explicit level of 4878 structuring in the initializer, including the outermost one. It 4879 saves the values of most of the variables above. */ 4880 4881struct constructor_range_stack; 4882 4883struct constructor_stack 4884{ 4885 struct constructor_stack *next; 4886 tree type; 4887 tree fields; 4888 tree index; 4889 tree max_index; 4890 tree unfilled_index; 4891 tree unfilled_fields; 4892 tree bit_index; 4893 VEC(constructor_elt,gc) *elements; 4894 struct init_node *pending_elts; 4895 int offset; 4896 int depth; 4897 /* If value nonzero, this value should replace the entire 4898 constructor at this level. */ 4899 struct c_expr replacement_value; 4900 struct constructor_range_stack *range_stack; 4901 char constant; 4902 char simple; 4903 char implicit; 4904 char erroneous; 4905 char outer; 4906 char incremental; 4907 char designated; 4908}; 4909 4910static struct constructor_stack *constructor_stack; 4911 4912/* This stack represents designators from some range designator up to 4913 the last designator in the list. */ 4914 4915struct constructor_range_stack 4916{ 4917 struct constructor_range_stack *next, *prev; 4918 struct constructor_stack *stack; 4919 tree range_start; 4920 tree index; 4921 tree range_end; 4922 tree fields; 4923}; 4924 4925static struct constructor_range_stack *constructor_range_stack; 4926 4927/* This stack records separate initializers that are nested. 4928 Nested initializers can't happen in ANSI C, but GNU C allows them 4929 in cases like { ... (struct foo) { ... } ... }. */ 4930 4931struct initializer_stack 4932{ 4933 struct initializer_stack *next; 4934 tree decl; 4935 struct constructor_stack *constructor_stack; 4936 struct constructor_range_stack *constructor_range_stack; 4937 VEC(constructor_elt,gc) *elements; 4938 struct spelling *spelling; 4939 struct spelling *spelling_base; 4940 int spelling_size; 4941 char top_level; 4942 char require_constant_value; 4943 char require_constant_elements; 4944}; 4945 4946static struct initializer_stack *initializer_stack; 4947 4948/* Prepare to parse and output the initializer for variable DECL. */ 4949 4950void 4951start_init (tree decl, tree asmspec_tree ATTRIBUTE_UNUSED, int top_level) 4952{ 4953 const char *locus; 4954 struct initializer_stack *p = XNEW (struct initializer_stack); 4955 4956 p->decl = constructor_decl; 4957 p->require_constant_value = require_constant_value; 4958 p->require_constant_elements = require_constant_elements; 4959 p->constructor_stack = constructor_stack; 4960 p->constructor_range_stack = constructor_range_stack; 4961 p->elements = constructor_elements; 4962 p->spelling = spelling; 4963 p->spelling_base = spelling_base; 4964 p->spelling_size = spelling_size; 4965 p->top_level = constructor_top_level; 4966 p->next = initializer_stack; 4967 initializer_stack = p; 4968 4969 constructor_decl = decl; 4970 constructor_designated = 0; 4971 constructor_top_level = top_level; 4972 4973 if (decl != 0 && decl != error_mark_node) 4974 { 4975 require_constant_value = TREE_STATIC (decl); 4976 require_constant_elements 4977 = ((TREE_STATIC (decl) || (pedantic && !flag_isoc99)) 4978 /* For a scalar, you can always use any value to initialize, 4979 even within braces. */ 4980 && (TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE 4981 || TREE_CODE (TREE_TYPE (decl)) == RECORD_TYPE 4982 || TREE_CODE (TREE_TYPE (decl)) == UNION_TYPE 4983 || TREE_CODE (TREE_TYPE (decl)) == QUAL_UNION_TYPE)); 4984 locus = IDENTIFIER_POINTER (DECL_NAME (decl)); 4985 } 4986 else 4987 { 4988 require_constant_value = 0; 4989 require_constant_elements = 0; 4990 locus = "(anonymous)"; 4991 } 4992 4993 constructor_stack = 0; 4994 constructor_range_stack = 0; 4995 4996 missing_braces_mentioned = 0; 4997 4998 spelling_base = 0; 4999 spelling_size = 0; 5000 RESTORE_SPELLING_DEPTH (0); 5001 5002 if (locus) 5003 push_string (locus); 5004} 5005 5006void 5007finish_init (void) 5008{ 5009 struct initializer_stack *p = initializer_stack; 5010 5011 /* Free the whole constructor stack of this initializer. */ 5012 while (constructor_stack) 5013 { 5014 struct constructor_stack *q = constructor_stack; 5015 constructor_stack = q->next; 5016 free (q); 5017 } 5018 5019 gcc_assert (!constructor_range_stack); 5020 5021 /* Pop back to the data of the outer initializer (if any). */ 5022 free (spelling_base); 5023 5024 constructor_decl = p->decl; 5025 require_constant_value = p->require_constant_value; 5026 require_constant_elements = p->require_constant_elements; 5027 constructor_stack = p->constructor_stack; 5028 constructor_range_stack = p->constructor_range_stack; 5029 constructor_elements = p->elements; 5030 spelling = p->spelling; 5031 spelling_base = p->spelling_base; 5032 spelling_size = p->spelling_size; 5033 constructor_top_level = p->top_level; 5034 initializer_stack = p->next; 5035 free (p); 5036} 5037 5038/* Call here when we see the initializer is surrounded by braces. 5039 This is instead of a call to push_init_level; 5040 it is matched by a call to pop_init_level. 5041 5042 TYPE is the type to initialize, for a constructor expression. 5043 For an initializer for a decl, TYPE is zero. */ 5044 5045void 5046really_start_incremental_init (tree type) 5047{ 5048 struct constructor_stack *p = XNEW (struct constructor_stack); 5049 5050 if (type == 0) 5051 type = TREE_TYPE (constructor_decl); 5052 5053 if (targetm.vector_opaque_p (type)) 5054 error ("opaque vector types cannot be initialized"); 5055 5056 p->type = constructor_type; 5057 p->fields = constructor_fields; 5058 p->index = constructor_index; 5059 p->max_index = constructor_max_index; 5060 p->unfilled_index = constructor_unfilled_index; 5061 p->unfilled_fields = constructor_unfilled_fields; 5062 p->bit_index = constructor_bit_index; 5063 p->elements = constructor_elements; 5064 p->constant = constructor_constant; 5065 p->simple = constructor_simple; 5066 p->erroneous = constructor_erroneous; 5067 p->pending_elts = constructor_pending_elts; 5068 p->depth = constructor_depth; 5069 p->replacement_value.value = 0; 5070 p->replacement_value.original_code = ERROR_MARK; 5071 p->implicit = 0; 5072 p->range_stack = 0; 5073 p->outer = 0; 5074 p->incremental = constructor_incremental; 5075 p->designated = constructor_designated; 5076 p->next = 0; 5077 constructor_stack = p; 5078 5079 constructor_constant = 1; 5080 constructor_simple = 1; 5081 constructor_depth = SPELLING_DEPTH (); 5082 constructor_elements = 0; 5083 constructor_pending_elts = 0; 5084 constructor_type = type; 5085 constructor_incremental = 1; 5086 constructor_designated = 0; 5087 designator_depth = 0; 5088 designator_erroneous = 0; 5089 5090 if (TREE_CODE (constructor_type) == RECORD_TYPE 5091 || TREE_CODE (constructor_type) == UNION_TYPE) 5092 { 5093 constructor_fields = TYPE_FIELDS (constructor_type); 5094 /* Skip any nameless bit fields at the beginning. */ 5095 while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields) 5096 && DECL_NAME (constructor_fields) == 0) 5097 constructor_fields = TREE_CHAIN (constructor_fields); 5098 5099 constructor_unfilled_fields = constructor_fields; 5100 constructor_bit_index = bitsize_zero_node; 5101 } 5102 else if (TREE_CODE (constructor_type) == ARRAY_TYPE) 5103 { 5104 if (TYPE_DOMAIN (constructor_type)) 5105 { 5106 constructor_max_index 5107 = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type)); 5108 5109 /* Detect non-empty initializations of zero-length arrays. */ 5110 if (constructor_max_index == NULL_TREE 5111 && TYPE_SIZE (constructor_type)) 5112 constructor_max_index = build_int_cst (NULL_TREE, -1); 5113 5114 /* constructor_max_index needs to be an INTEGER_CST. Attempts 5115 to initialize VLAs will cause a proper error; avoid tree 5116 checking errors as well by setting a safe value. */ 5117 if (constructor_max_index 5118 && TREE_CODE (constructor_max_index) != INTEGER_CST) 5119 constructor_max_index = build_int_cst (NULL_TREE, -1); 5120 5121 constructor_index 5122 = convert (bitsizetype, 5123 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type))); 5124 } 5125 else 5126 { 5127 constructor_index = bitsize_zero_node; 5128 constructor_max_index = NULL_TREE; 5129 } 5130 5131 constructor_unfilled_index = constructor_index; 5132 } 5133 else if (TREE_CODE (constructor_type) == VECTOR_TYPE) 5134 { 5135 /* Vectors are like simple fixed-size arrays. */ 5136 constructor_max_index = 5137 build_int_cst (NULL_TREE, TYPE_VECTOR_SUBPARTS (constructor_type) - 1); 5138 constructor_index = bitsize_zero_node; 5139 constructor_unfilled_index = constructor_index; 5140 } 5141 else 5142 { 5143 /* Handle the case of int x = {5}; */ 5144 constructor_fields = constructor_type; 5145 constructor_unfilled_fields = constructor_type; 5146 } 5147} 5148 5149/* Push down into a subobject, for initialization. 5150 If this is for an explicit set of braces, IMPLICIT is 0. 5151 If it is because the next element belongs at a lower level, 5152 IMPLICIT is 1 (or 2 if the push is because of designator list). */ 5153 5154void 5155push_init_level (int implicit) 5156{ 5157 struct constructor_stack *p; 5158 tree value = NULL_TREE; 5159 5160 /* If we've exhausted any levels that didn't have braces, 5161 pop them now. If implicit == 1, this will have been done in 5162 process_init_element; do not repeat it here because in the case 5163 of excess initializers for an empty aggregate this leads to an 5164 infinite cycle of popping a level and immediately recreating 5165 it. */ 5166 if (implicit != 1) 5167 { 5168 while (constructor_stack->implicit) 5169 { 5170 if ((TREE_CODE (constructor_type) == RECORD_TYPE 5171 || TREE_CODE (constructor_type) == UNION_TYPE) 5172 && constructor_fields == 0) 5173 process_init_element (pop_init_level (1)); 5174 else if (TREE_CODE (constructor_type) == ARRAY_TYPE 5175 && constructor_max_index 5176 && tree_int_cst_lt (constructor_max_index, 5177 constructor_index)) 5178 process_init_element (pop_init_level (1)); 5179 else 5180 break; 5181 } 5182 } 5183 5184 /* Unless this is an explicit brace, we need to preserve previous 5185 content if any. */ 5186 if (implicit) 5187 { 5188 if ((TREE_CODE (constructor_type) == RECORD_TYPE 5189 || TREE_CODE (constructor_type) == UNION_TYPE) 5190 && constructor_fields) 5191 value = find_init_member (constructor_fields); 5192 else if (TREE_CODE (constructor_type) == ARRAY_TYPE) 5193 value = find_init_member (constructor_index); 5194 } 5195 5196 p = XNEW (struct constructor_stack); 5197 p->type = constructor_type; 5198 p->fields = constructor_fields; 5199 p->index = constructor_index; 5200 p->max_index = constructor_max_index; 5201 p->unfilled_index = constructor_unfilled_index; 5202 p->unfilled_fields = constructor_unfilled_fields; 5203 p->bit_index = constructor_bit_index; 5204 p->elements = constructor_elements; 5205 p->constant = constructor_constant; 5206 p->simple = constructor_simple; 5207 p->erroneous = constructor_erroneous; 5208 p->pending_elts = constructor_pending_elts; 5209 p->depth = constructor_depth; 5210 p->replacement_value.value = 0; 5211 p->replacement_value.original_code = ERROR_MARK; 5212 p->implicit = implicit; 5213 p->outer = 0; 5214 p->incremental = constructor_incremental; 5215 p->designated = constructor_designated; 5216 p->next = constructor_stack; 5217 p->range_stack = 0; 5218 constructor_stack = p; 5219 5220 constructor_constant = 1; 5221 constructor_simple = 1; 5222 constructor_depth = SPELLING_DEPTH (); 5223 constructor_elements = 0; 5224 constructor_incremental = 1; 5225 constructor_designated = 0; 5226 constructor_pending_elts = 0; 5227 if (!implicit) 5228 { 5229 p->range_stack = constructor_range_stack; 5230 constructor_range_stack = 0; 5231 designator_depth = 0; 5232 designator_erroneous = 0; 5233 } 5234 5235 /* Don't die if an entire brace-pair level is superfluous 5236 in the containing level. */ 5237 if (constructor_type == 0) 5238 ; 5239 else if (TREE_CODE (constructor_type) == RECORD_TYPE 5240 || TREE_CODE (constructor_type) == UNION_TYPE) 5241 { 5242 /* Don't die if there are extra init elts at the end. */ 5243 if (constructor_fields == 0) 5244 constructor_type = 0; 5245 else 5246 { 5247 constructor_type = TREE_TYPE (constructor_fields); 5248 push_member_name (constructor_fields); 5249 constructor_depth++; 5250 } 5251 } 5252 else if (TREE_CODE (constructor_type) == ARRAY_TYPE) 5253 { 5254 constructor_type = TREE_TYPE (constructor_type); 5255 push_array_bounds (tree_low_cst (constructor_index, 1)); 5256 constructor_depth++; 5257 } 5258 5259 if (constructor_type == 0) 5260 { 5261 error_init ("extra brace group at end of initializer"); 5262 constructor_fields = 0; 5263 constructor_unfilled_fields = 0; 5264 return; 5265 } 5266 5267 if (value && TREE_CODE (value) == CONSTRUCTOR) 5268 { 5269 constructor_constant = TREE_CONSTANT (value); 5270 constructor_simple = TREE_STATIC (value); 5271 constructor_elements = CONSTRUCTOR_ELTS (value); 5272 if (!VEC_empty (constructor_elt, constructor_elements) 5273 && (TREE_CODE (constructor_type) == RECORD_TYPE 5274 || TREE_CODE (constructor_type) == ARRAY_TYPE)) 5275 set_nonincremental_init (); 5276 } 5277 5278 if (implicit == 1 && warn_missing_braces && !missing_braces_mentioned) 5279 { 5280 missing_braces_mentioned = 1; 5281 warning_init ("missing braces around initializer"); 5282 } 5283 5284 if (TREE_CODE (constructor_type) == RECORD_TYPE 5285 || TREE_CODE (constructor_type) == UNION_TYPE) 5286 { 5287 constructor_fields = TYPE_FIELDS (constructor_type); 5288 /* Skip any nameless bit fields at the beginning. */ 5289 while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields) 5290 && DECL_NAME (constructor_fields) == 0) 5291 constructor_fields = TREE_CHAIN (constructor_fields); 5292 5293 constructor_unfilled_fields = constructor_fields; 5294 constructor_bit_index = bitsize_zero_node; 5295 } 5296 else if (TREE_CODE (constructor_type) == VECTOR_TYPE) 5297 { 5298 /* Vectors are like simple fixed-size arrays. */ 5299 constructor_max_index = 5300 build_int_cst (NULL_TREE, TYPE_VECTOR_SUBPARTS (constructor_type) - 1); 5301 constructor_index = convert (bitsizetype, integer_zero_node); 5302 constructor_unfilled_index = constructor_index; 5303 } 5304 else if (TREE_CODE (constructor_type) == ARRAY_TYPE) 5305 { 5306 if (TYPE_DOMAIN (constructor_type)) 5307 { 5308 constructor_max_index 5309 = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type)); 5310 5311 /* Detect non-empty initializations of zero-length arrays. */ 5312 if (constructor_max_index == NULL_TREE 5313 && TYPE_SIZE (constructor_type)) 5314 constructor_max_index = build_int_cst (NULL_TREE, -1); 5315 5316 /* constructor_max_index needs to be an INTEGER_CST. Attempts 5317 to initialize VLAs will cause a proper error; avoid tree 5318 checking errors as well by setting a safe value. */ 5319 if (constructor_max_index 5320 && TREE_CODE (constructor_max_index) != INTEGER_CST) 5321 constructor_max_index = build_int_cst (NULL_TREE, -1); 5322 5323 constructor_index 5324 = convert (bitsizetype, 5325 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type))); 5326 } 5327 else 5328 constructor_index = bitsize_zero_node; 5329 5330 constructor_unfilled_index = constructor_index; 5331 if (value && TREE_CODE (value) == STRING_CST) 5332 { 5333 /* We need to split the char/wchar array into individual 5334 characters, so that we don't have to special case it 5335 everywhere. */ 5336 set_nonincremental_init_from_string (value); 5337 } 5338 } 5339 else 5340 { 5341 if (constructor_type != error_mark_node) 5342 warning_init ("braces around scalar initializer"); 5343 constructor_fields = constructor_type; 5344 constructor_unfilled_fields = constructor_type; 5345 } 5346} 5347 5348/* At the end of an implicit or explicit brace level, 5349 finish up that level of constructor. If a single expression 5350 with redundant braces initialized that level, return the 5351 c_expr structure for that expression. Otherwise, the original_code 5352 element is set to ERROR_MARK. 5353 If we were outputting the elements as they are read, return 0 as the value 5354 from inner levels (process_init_element ignores that), 5355 but return error_mark_node as the value from the outermost level 5356 (that's what we want to put in DECL_INITIAL). 5357 Otherwise, return a CONSTRUCTOR expression as the value. */ 5358 5359struct c_expr 5360pop_init_level (int implicit) 5361{ 5362 struct constructor_stack *p; 5363 struct c_expr ret; 5364 ret.value = 0; 5365 ret.original_code = ERROR_MARK; 5366 5367 if (implicit == 0) 5368 { 5369 /* When we come to an explicit close brace, 5370 pop any inner levels that didn't have explicit braces. */ 5371 while (constructor_stack->implicit) 5372 process_init_element (pop_init_level (1)); 5373 5374 gcc_assert (!constructor_range_stack); 5375 } 5376 5377 /* Now output all pending elements. */ 5378 constructor_incremental = 1; 5379 output_pending_init_elements (1); 5380 5381 p = constructor_stack; 5382 5383 /* Error for initializing a flexible array member, or a zero-length 5384 array member in an inappropriate context. */ 5385 if (constructor_type && constructor_fields 5386 && TREE_CODE (constructor_type) == ARRAY_TYPE 5387 && TYPE_DOMAIN (constructor_type) 5388 && !TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type))) 5389 { 5390 /* Silently discard empty initializations. The parser will 5391 already have pedwarned for empty brackets. */ 5392 if (integer_zerop (constructor_unfilled_index)) 5393 constructor_type = NULL_TREE; 5394 else 5395 { 5396 gcc_assert (!TYPE_SIZE (constructor_type)); 5397 5398 if (constructor_depth > 2) 5399 error_init ("initialization of flexible array member in a nested context"); 5400 else if (pedantic) 5401 pedwarn_init ("initialization of a flexible array member"); 5402 5403 /* We have already issued an error message for the existence 5404 of a flexible array member not at the end of the structure. 5405 Discard the initializer so that we do not die later. */ 5406 if (TREE_CHAIN (constructor_fields) != NULL_TREE) 5407 constructor_type = NULL_TREE; 5408 } 5409 } 5410 5411 /* Warn when some struct elements are implicitly initialized to zero. */ 5412 if (warn_missing_field_initializers 5413 && constructor_type 5414 && TREE_CODE (constructor_type) == RECORD_TYPE 5415 && constructor_unfilled_fields) 5416 { 5417 /* Do not warn for flexible array members or zero-length arrays. */ 5418 while (constructor_unfilled_fields 5419 && (!DECL_SIZE (constructor_unfilled_fields) 5420 || integer_zerop (DECL_SIZE (constructor_unfilled_fields)))) 5421 constructor_unfilled_fields = TREE_CHAIN (constructor_unfilled_fields); 5422 5423 /* Do not warn if this level of the initializer uses member 5424 designators; it is likely to be deliberate. */ 5425 if (constructor_unfilled_fields && !constructor_designated) 5426 { 5427 push_member_name (constructor_unfilled_fields); 5428 warning_init ("missing initializer"); 5429 RESTORE_SPELLING_DEPTH (constructor_depth); 5430 } 5431 } 5432 5433 /* Pad out the end of the structure. */ 5434 if (p->replacement_value.value) 5435 /* If this closes a superfluous brace pair, 5436 just pass out the element between them. */ 5437 ret = p->replacement_value; 5438 else if (constructor_type == 0) 5439 ; 5440 else if (TREE_CODE (constructor_type) != RECORD_TYPE 5441 && TREE_CODE (constructor_type) != UNION_TYPE 5442 && TREE_CODE (constructor_type) != ARRAY_TYPE 5443 && TREE_CODE (constructor_type) != VECTOR_TYPE) 5444 { 5445 /* A nonincremental scalar initializer--just return 5446 the element, after verifying there is just one. */ 5447 if (VEC_empty (constructor_elt,constructor_elements)) 5448 { 5449 if (!constructor_erroneous) 5450 error_init ("empty scalar initializer"); 5451 ret.value = error_mark_node; 5452 } 5453 else if (VEC_length (constructor_elt,constructor_elements) != 1) 5454 { 5455 error_init ("extra elements in scalar initializer"); 5456 ret.value = VEC_index (constructor_elt,constructor_elements,0)->value; 5457 } 5458 else 5459 ret.value = VEC_index (constructor_elt,constructor_elements,0)->value; 5460 } 5461 else 5462 { 5463 if (constructor_erroneous) 5464 ret.value = error_mark_node; 5465 else 5466 { 5467 ret.value = build_constructor (constructor_type, 5468 constructor_elements); 5469 if (constructor_constant) 5470 TREE_CONSTANT (ret.value) = TREE_INVARIANT (ret.value) = 1; 5471 if (constructor_constant && constructor_simple) 5472 TREE_STATIC (ret.value) = 1; 5473 } 5474 } 5475 5476 constructor_type = p->type; 5477 constructor_fields = p->fields; 5478 constructor_index = p->index; 5479 constructor_max_index = p->max_index; 5480 constructor_unfilled_index = p->unfilled_index; 5481 constructor_unfilled_fields = p->unfilled_fields; 5482 constructor_bit_index = p->bit_index; 5483 constructor_elements = p->elements; 5484 constructor_constant = p->constant; 5485 constructor_simple = p->simple; 5486 constructor_erroneous = p->erroneous; 5487 constructor_incremental = p->incremental; 5488 constructor_designated = p->designated; 5489 constructor_pending_elts = p->pending_elts; 5490 constructor_depth = p->depth; 5491 if (!p->implicit) 5492 constructor_range_stack = p->range_stack; 5493 RESTORE_SPELLING_DEPTH (constructor_depth); 5494 5495 constructor_stack = p->next; 5496 free (p); 5497 5498 if (ret.value == 0 && constructor_stack == 0) 5499 ret.value = error_mark_node; 5500 return ret; 5501} 5502 5503/* Common handling for both array range and field name designators. 5504 ARRAY argument is nonzero for array ranges. Returns zero for success. */ 5505 5506static int 5507set_designator (int array) 5508{ 5509 tree subtype; 5510 enum tree_code subcode; 5511 5512 /* Don't die if an entire brace-pair level is superfluous 5513 in the containing level. */ 5514 if (constructor_type == 0) 5515 return 1; 5516 5517 /* If there were errors in this designator list already, bail out 5518 silently. */ 5519 if (designator_erroneous) 5520 return 1; 5521 5522 if (!designator_depth) 5523 { 5524 gcc_assert (!constructor_range_stack); 5525 5526 /* Designator list starts at the level of closest explicit 5527 braces. */ 5528 while (constructor_stack->implicit) 5529 process_init_element (pop_init_level (1)); 5530 constructor_designated = 1; 5531 return 0; 5532 } 5533 5534 switch (TREE_CODE (constructor_type)) 5535 { 5536 case RECORD_TYPE: 5537 case UNION_TYPE: 5538 subtype = TREE_TYPE (constructor_fields); 5539 if (subtype != error_mark_node) 5540 subtype = TYPE_MAIN_VARIANT (subtype); 5541 break; 5542 case ARRAY_TYPE: 5543 subtype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type)); 5544 break; 5545 default: 5546 gcc_unreachable (); 5547 } 5548 5549 subcode = TREE_CODE (subtype); 5550 if (array && subcode != ARRAY_TYPE) 5551 { 5552 error_init ("array index in non-array initializer"); 5553 return 1; 5554 } 5555 else if (!array && subcode != RECORD_TYPE && subcode != UNION_TYPE) 5556 { 5557 error_init ("field name not in record or union initializer"); 5558 return 1; 5559 } 5560 5561 constructor_designated = 1; 5562 push_init_level (2); 5563 return 0; 5564} 5565 5566/* If there are range designators in designator list, push a new designator 5567 to constructor_range_stack. RANGE_END is end of such stack range or 5568 NULL_TREE if there is no range designator at this level. */ 5569 5570static void 5571push_range_stack (tree range_end) 5572{ 5573 struct constructor_range_stack *p; 5574 5575 p = GGC_NEW (struct constructor_range_stack); 5576 p->prev = constructor_range_stack; 5577 p->next = 0; 5578 p->fields = constructor_fields; 5579 p->range_start = constructor_index; 5580 p->index = constructor_index; 5581 p->stack = constructor_stack; 5582 p->range_end = range_end; 5583 if (constructor_range_stack) 5584 constructor_range_stack->next = p; 5585 constructor_range_stack = p; 5586} 5587 5588/* Within an array initializer, specify the next index to be initialized. 5589 FIRST is that index. If LAST is nonzero, then initialize a range 5590 of indices, running from FIRST through LAST. */ 5591 5592void 5593set_init_index (tree first, tree last) 5594{ 5595 if (set_designator (1)) 5596 return; 5597 5598 designator_erroneous = 1; 5599 5600 if (!INTEGRAL_TYPE_P (TREE_TYPE (first)) 5601 || (last && !INTEGRAL_TYPE_P (TREE_TYPE (last)))) 5602 { 5603 error_init ("array index in initializer not of integer type"); 5604 return; 5605 } 5606 5607 if (TREE_CODE (first) != INTEGER_CST) 5608 error_init ("nonconstant array index in initializer"); 5609 else if (last != 0 && TREE_CODE (last) != INTEGER_CST) 5610 error_init ("nonconstant array index in initializer"); 5611 else if (TREE_CODE (constructor_type) != ARRAY_TYPE) 5612 error_init ("array index in non-array initializer"); 5613 else if (tree_int_cst_sgn (first) == -1) 5614 error_init ("array index in initializer exceeds array bounds"); 5615 else if (constructor_max_index 5616 && tree_int_cst_lt (constructor_max_index, first)) 5617 error_init ("array index in initializer exceeds array bounds"); 5618 else 5619 { 5620 constructor_index = convert (bitsizetype, first); 5621 5622 if (last) 5623 { 5624 if (tree_int_cst_equal (first, last)) 5625 last = 0; 5626 else if (tree_int_cst_lt (last, first)) 5627 { 5628 error_init ("empty index range in initializer"); 5629 last = 0; 5630 } 5631 else 5632 { 5633 last = convert (bitsizetype, last); 5634 if (constructor_max_index != 0 5635 && tree_int_cst_lt (constructor_max_index, last)) 5636 { 5637 error_init ("array index range in initializer exceeds array bounds"); 5638 last = 0; 5639 } 5640 } 5641 } 5642 5643 designator_depth++; 5644 designator_erroneous = 0; 5645 if (constructor_range_stack || last) 5646 push_range_stack (last); 5647 } 5648} 5649 5650/* Within a struct initializer, specify the next field to be initialized. */ 5651 5652void 5653set_init_label (tree fieldname) 5654{ 5655 tree tail; 5656 5657 if (set_designator (0)) 5658 return; 5659 5660 designator_erroneous = 1; 5661 5662 if (TREE_CODE (constructor_type) != RECORD_TYPE 5663 && TREE_CODE (constructor_type) != UNION_TYPE) 5664 { 5665 error_init ("field name not in record or union initializer"); 5666 return; 5667 } 5668 5669 for (tail = TYPE_FIELDS (constructor_type); tail; 5670 tail = TREE_CHAIN (tail)) 5671 { 5672 if (DECL_NAME (tail) == fieldname) 5673 break; 5674 } 5675 5676 if (tail == 0) 5677 error ("unknown field %qE specified in initializer", fieldname); 5678 else 5679 { 5680 constructor_fields = tail; 5681 designator_depth++; 5682 designator_erroneous = 0; 5683 if (constructor_range_stack) 5684 push_range_stack (NULL_TREE); 5685 } 5686} 5687 5688/* Add a new initializer to the tree of pending initializers. PURPOSE 5689 identifies the initializer, either array index or field in a structure. 5690 VALUE is the value of that index or field. */ 5691 5692static void 5693add_pending_init (tree purpose, tree value) 5694{ 5695 struct init_node *p, **q, *r; 5696 5697 q = &constructor_pending_elts; 5698 p = 0; 5699 5700 if (TREE_CODE (constructor_type) == ARRAY_TYPE) 5701 { 5702 while (*q != 0) 5703 { 5704 p = *q; 5705 if (tree_int_cst_lt (purpose, p->purpose)) 5706 q = &p->left; 5707 else if (tree_int_cst_lt (p->purpose, purpose)) 5708 q = &p->right; 5709 else 5710 { 5711 if (TREE_SIDE_EFFECTS (p->value)) 5712 warning_init ("initialized field with side-effects overwritten"); 5713 else if (warn_override_init) 5714 warning_init ("initialized field overwritten"); 5715 p->value = value; 5716 return; 5717 } 5718 } 5719 } 5720 else 5721 { 5722 tree bitpos; 5723 5724 bitpos = bit_position (purpose); 5725 while (*q != NULL) 5726 { 5727 p = *q; 5728 if (tree_int_cst_lt (bitpos, bit_position (p->purpose))) 5729 q = &p->left; 5730 else if (p->purpose != purpose) 5731 q = &p->right; 5732 else 5733 { 5734 if (TREE_SIDE_EFFECTS (p->value)) 5735 warning_init ("initialized field with side-effects overwritten"); 5736 else if (warn_override_init) 5737 warning_init ("initialized field overwritten"); 5738 p->value = value; 5739 return; 5740 } 5741 } 5742 } 5743 5744 r = GGC_NEW (struct init_node); 5745 r->purpose = purpose; 5746 r->value = value; 5747 5748 *q = r; 5749 r->parent = p; 5750 r->left = 0; 5751 r->right = 0; 5752 r->balance = 0; 5753 5754 while (p) 5755 { 5756 struct init_node *s; 5757 5758 if (r == p->left) 5759 { 5760 if (p->balance == 0) 5761 p->balance = -1; 5762 else if (p->balance < 0) 5763 { 5764 if (r->balance < 0) 5765 { 5766 /* L rotation. */ 5767 p->left = r->right; 5768 if (p->left) 5769 p->left->parent = p; 5770 r->right = p; 5771 5772 p->balance = 0; 5773 r->balance = 0; 5774 5775 s = p->parent; 5776 p->parent = r; 5777 r->parent = s; 5778 if (s) 5779 { 5780 if (s->left == p) 5781 s->left = r; 5782 else 5783 s->right = r; 5784 } 5785 else 5786 constructor_pending_elts = r; 5787 } 5788 else 5789 { 5790 /* LR rotation. */ 5791 struct init_node *t = r->right; 5792 5793 r->right = t->left; 5794 if (r->right) 5795 r->right->parent = r; 5796 t->left = r; 5797 5798 p->left = t->right; 5799 if (p->left) 5800 p->left->parent = p; 5801 t->right = p; 5802 5803 p->balance = t->balance < 0; 5804 r->balance = -(t->balance > 0); 5805 t->balance = 0; 5806 5807 s = p->parent; 5808 p->parent = t; 5809 r->parent = t; 5810 t->parent = s; 5811 if (s) 5812 { 5813 if (s->left == p) 5814 s->left = t; 5815 else 5816 s->right = t; 5817 } 5818 else 5819 constructor_pending_elts = t; 5820 } 5821 break; 5822 } 5823 else 5824 { 5825 /* p->balance == +1; growth of left side balances the node. */ 5826 p->balance = 0; 5827 break; 5828 } 5829 } 5830 else /* r == p->right */ 5831 { 5832 if (p->balance == 0) 5833 /* Growth propagation from right side. */ 5834 p->balance++; 5835 else if (p->balance > 0) 5836 { 5837 if (r->balance > 0) 5838 { 5839 /* R rotation. */ 5840 p->right = r->left; 5841 if (p->right) 5842 p->right->parent = p; 5843 r->left = p; 5844 5845 p->balance = 0; 5846 r->balance = 0; 5847 5848 s = p->parent; 5849 p->parent = r; 5850 r->parent = s; 5851 if (s) 5852 { 5853 if (s->left == p) 5854 s->left = r; 5855 else 5856 s->right = r; 5857 } 5858 else 5859 constructor_pending_elts = r; 5860 } 5861 else /* r->balance == -1 */ 5862 { 5863 /* RL rotation */ 5864 struct init_node *t = r->left; 5865 5866 r->left = t->right; 5867 if (r->left) 5868 r->left->parent = r; 5869 t->right = r; 5870 5871 p->right = t->left; 5872 if (p->right) 5873 p->right->parent = p; 5874 t->left = p; 5875 5876 r->balance = (t->balance < 0); 5877 p->balance = -(t->balance > 0); 5878 t->balance = 0; 5879 5880 s = p->parent; 5881 p->parent = t; 5882 r->parent = t; 5883 t->parent = s; 5884 if (s) 5885 { 5886 if (s->left == p) 5887 s->left = t; 5888 else 5889 s->right = t; 5890 } 5891 else 5892 constructor_pending_elts = t; 5893 } 5894 break; 5895 } 5896 else 5897 { 5898 /* p->balance == -1; growth of right side balances the node. */ 5899 p->balance = 0; 5900 break; 5901 } 5902 } 5903 5904 r = p; 5905 p = p->parent; 5906 } 5907} 5908 5909/* Build AVL tree from a sorted chain. */ 5910 5911static void 5912set_nonincremental_init (void) 5913{ 5914 unsigned HOST_WIDE_INT ix; 5915 tree index, value; 5916 5917 if (TREE_CODE (constructor_type) != RECORD_TYPE 5918 && TREE_CODE (constructor_type) != ARRAY_TYPE) 5919 return; 5920 5921 FOR_EACH_CONSTRUCTOR_ELT (constructor_elements, ix, index, value) 5922 add_pending_init (index, value); 5923 constructor_elements = 0; 5924 if (TREE_CODE (constructor_type) == RECORD_TYPE) 5925 { 5926 constructor_unfilled_fields = TYPE_FIELDS (constructor_type); 5927 /* Skip any nameless bit fields at the beginning. */ 5928 while (constructor_unfilled_fields != 0 5929 && DECL_C_BIT_FIELD (constructor_unfilled_fields) 5930 && DECL_NAME (constructor_unfilled_fields) == 0) 5931 constructor_unfilled_fields = TREE_CHAIN (constructor_unfilled_fields); 5932 5933 } 5934 else if (TREE_CODE (constructor_type) == ARRAY_TYPE) 5935 { 5936 if (TYPE_DOMAIN (constructor_type)) 5937 constructor_unfilled_index 5938 = convert (bitsizetype, 5939 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type))); 5940 else 5941 constructor_unfilled_index = bitsize_zero_node; 5942 } 5943 constructor_incremental = 0; 5944} 5945 5946/* Build AVL tree from a string constant. */ 5947 5948static void 5949set_nonincremental_init_from_string (tree str) 5950{ 5951 tree value, purpose, type; 5952 HOST_WIDE_INT val[2]; 5953 const char *p, *end; 5954 int byte, wchar_bytes, charwidth, bitpos; 5955 5956 gcc_assert (TREE_CODE (constructor_type) == ARRAY_TYPE); 5957 5958 if (TYPE_PRECISION (TREE_TYPE (TREE_TYPE (str))) 5959 == TYPE_PRECISION (char_type_node)) 5960 wchar_bytes = 1; 5961 else 5962 { 5963 gcc_assert (TYPE_PRECISION (TREE_TYPE (TREE_TYPE (str))) 5964 == TYPE_PRECISION (wchar_type_node)); 5965 wchar_bytes = TYPE_PRECISION (wchar_type_node) / BITS_PER_UNIT; 5966 } 5967 charwidth = TYPE_PRECISION (char_type_node); 5968 type = TREE_TYPE (constructor_type); 5969 p = TREE_STRING_POINTER (str); 5970 end = p + TREE_STRING_LENGTH (str); 5971 5972 for (purpose = bitsize_zero_node; 5973 p < end && !tree_int_cst_lt (constructor_max_index, purpose); 5974 purpose = size_binop (PLUS_EXPR, purpose, bitsize_one_node)) 5975 { 5976 if (wchar_bytes == 1) 5977 { 5978 val[1] = (unsigned char) *p++; 5979 val[0] = 0; 5980 } 5981 else 5982 { 5983 val[0] = 0; 5984 val[1] = 0; 5985 for (byte = 0; byte < wchar_bytes; byte++) 5986 { 5987 if (BYTES_BIG_ENDIAN) 5988 bitpos = (wchar_bytes - byte - 1) * charwidth; 5989 else 5990 bitpos = byte * charwidth; 5991 val[bitpos < HOST_BITS_PER_WIDE_INT] 5992 |= ((unsigned HOST_WIDE_INT) ((unsigned char) *p++)) 5993 << (bitpos % HOST_BITS_PER_WIDE_INT); 5994 } 5995 } 5996 5997 if (!TYPE_UNSIGNED (type)) 5998 { 5999 bitpos = ((wchar_bytes - 1) * charwidth) + HOST_BITS_PER_CHAR; 6000 if (bitpos < HOST_BITS_PER_WIDE_INT) 6001 { 6002 if (val[1] & (((HOST_WIDE_INT) 1) << (bitpos - 1))) 6003 { 6004 val[1] |= ((HOST_WIDE_INT) -1) << bitpos; 6005 val[0] = -1; 6006 } 6007 } 6008 else if (bitpos == HOST_BITS_PER_WIDE_INT) 6009 { 6010 if (val[1] < 0) 6011 val[0] = -1; 6012 } 6013 else if (val[0] & (((HOST_WIDE_INT) 1) 6014 << (bitpos - 1 - HOST_BITS_PER_WIDE_INT))) 6015 val[0] |= ((HOST_WIDE_INT) -1) 6016 << (bitpos - HOST_BITS_PER_WIDE_INT); 6017 } 6018 6019 value = build_int_cst_wide (type, val[1], val[0]); 6020 add_pending_init (purpose, value); 6021 } 6022 6023 constructor_incremental = 0; 6024} 6025 6026/* Return value of FIELD in pending initializer or zero if the field was 6027 not initialized yet. */ 6028 6029static tree 6030find_init_member (tree field) 6031{ 6032 struct init_node *p; 6033 6034 if (TREE_CODE (constructor_type) == ARRAY_TYPE) 6035 { 6036 if (constructor_incremental 6037 && tree_int_cst_lt (field, constructor_unfilled_index)) 6038 set_nonincremental_init (); 6039 6040 p = constructor_pending_elts; 6041 while (p) 6042 { 6043 if (tree_int_cst_lt (field, p->purpose)) 6044 p = p->left; 6045 else if (tree_int_cst_lt (p->purpose, field)) 6046 p = p->right; 6047 else 6048 return p->value; 6049 } 6050 } 6051 else if (TREE_CODE (constructor_type) == RECORD_TYPE) 6052 { 6053 tree bitpos = bit_position (field); 6054 6055 if (constructor_incremental 6056 && (!constructor_unfilled_fields 6057 || tree_int_cst_lt (bitpos, 6058 bit_position (constructor_unfilled_fields)))) 6059 set_nonincremental_init (); 6060 6061 p = constructor_pending_elts; 6062 while (p) 6063 { 6064 if (field == p->purpose) 6065 return p->value; 6066 else if (tree_int_cst_lt (bitpos, bit_position (p->purpose))) 6067 p = p->left; 6068 else 6069 p = p->right; 6070 } 6071 } 6072 else if (TREE_CODE (constructor_type) == UNION_TYPE) 6073 { 6074 if (!VEC_empty (constructor_elt, constructor_elements) 6075 && (VEC_last (constructor_elt, constructor_elements)->index 6076 == field)) 6077 return VEC_last (constructor_elt, constructor_elements)->value; 6078 } 6079 return 0; 6080} 6081 6082/* "Output" the next constructor element. 6083 At top level, really output it to assembler code now. 6084 Otherwise, collect it in a list from which we will make a CONSTRUCTOR. 6085 TYPE is the data type that the containing data type wants here. 6086 FIELD is the field (a FIELD_DECL) or the index that this element fills. 6087 If VALUE is a string constant, STRICT_STRING is true if it is 6088 unparenthesized or we should not warn here for it being parenthesized. 6089 For other types of VALUE, STRICT_STRING is not used. 6090 6091 PENDING if non-nil means output pending elements that belong 6092 right after this element. (PENDING is normally 1; 6093 it is 0 while outputting pending elements, to avoid recursion.) */ 6094 6095static void 6096output_init_element (tree value, bool strict_string, tree type, tree field, 6097 int pending) 6098{ 6099 constructor_elt *celt; 6100 6101 if (type == error_mark_node || value == error_mark_node) 6102 { 6103 constructor_erroneous = 1; 6104 return; 6105 } 6106 if (TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE 6107 && (TREE_CODE (value) == STRING_CST 6108 || TREE_CODE (value) == COMPOUND_LITERAL_EXPR) 6109 && !(TREE_CODE (value) == STRING_CST 6110 && TREE_CODE (type) == ARRAY_TYPE 6111 && INTEGRAL_TYPE_P (TREE_TYPE (type))) 6112 && !comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (value)), 6113 TYPE_MAIN_VARIANT (type))) 6114 value = array_to_pointer_conversion (value); 6115 6116 if (TREE_CODE (value) == COMPOUND_LITERAL_EXPR 6117 && require_constant_value && !flag_isoc99 && pending) 6118 { 6119 /* As an extension, allow initializing objects with static storage 6120 duration with compound literals (which are then treated just as 6121 the brace enclosed list they contain). */ 6122 tree decl = COMPOUND_LITERAL_EXPR_DECL (value); 6123 value = DECL_INITIAL (decl); 6124 } 6125 6126 if (value == error_mark_node) 6127 constructor_erroneous = 1; 6128 else if (!TREE_CONSTANT (value)) 6129 constructor_constant = 0; 6130 else if (!initializer_constant_valid_p (value, TREE_TYPE (value)) 6131 || ((TREE_CODE (constructor_type) == RECORD_TYPE 6132 || TREE_CODE (constructor_type) == UNION_TYPE) 6133 && DECL_C_BIT_FIELD (field) 6134 && TREE_CODE (value) != INTEGER_CST)) 6135 constructor_simple = 0; 6136 6137 if (!initializer_constant_valid_p (value, TREE_TYPE (value))) 6138 { 6139 if (require_constant_value) 6140 { 6141 error_init ("initializer element is not constant"); 6142 value = error_mark_node; 6143 } 6144 else if (require_constant_elements) 6145 pedwarn ("initializer element is not computable at load time"); 6146 } 6147 6148 /* If this field is empty (and not at the end of structure), 6149 don't do anything other than checking the initializer. */ 6150 if (field 6151 && (TREE_TYPE (field) == error_mark_node 6152 || (COMPLETE_TYPE_P (TREE_TYPE (field)) 6153 && integer_zerop (TYPE_SIZE (TREE_TYPE (field))) 6154 && (TREE_CODE (constructor_type) == ARRAY_TYPE 6155 || TREE_CHAIN (field))))) 6156 return; 6157 6158 value = digest_init (type, value, strict_string, require_constant_value); 6159 if (value == error_mark_node) 6160 { 6161 constructor_erroneous = 1; 6162 return; 6163 } 6164 6165 /* If this element doesn't come next in sequence, 6166 put it on constructor_pending_elts. */ 6167 if (TREE_CODE (constructor_type) == ARRAY_TYPE 6168 && (!constructor_incremental 6169 || !tree_int_cst_equal (field, constructor_unfilled_index))) 6170 { 6171 if (constructor_incremental 6172 && tree_int_cst_lt (field, constructor_unfilled_index)) 6173 set_nonincremental_init (); 6174 6175 add_pending_init (field, value); 6176 return; 6177 } 6178 else if (TREE_CODE (constructor_type) == RECORD_TYPE 6179 && (!constructor_incremental 6180 || field != constructor_unfilled_fields)) 6181 { 6182 /* We do this for records but not for unions. In a union, 6183 no matter which field is specified, it can be initialized 6184 right away since it starts at the beginning of the union. */ 6185 if (constructor_incremental) 6186 { 6187 if (!constructor_unfilled_fields) 6188 set_nonincremental_init (); 6189 else 6190 { 6191 tree bitpos, unfillpos; 6192 6193 bitpos = bit_position (field); 6194 unfillpos = bit_position (constructor_unfilled_fields); 6195 6196 if (tree_int_cst_lt (bitpos, unfillpos)) 6197 set_nonincremental_init (); 6198 } 6199 } 6200 6201 add_pending_init (field, value); 6202 return; 6203 } 6204 else if (TREE_CODE (constructor_type) == UNION_TYPE 6205 && !VEC_empty (constructor_elt, constructor_elements)) 6206 { 6207 if (TREE_SIDE_EFFECTS (VEC_last (constructor_elt, 6208 constructor_elements)->value)) 6209 warning_init ("initialized field with side-effects overwritten"); 6210 else if (warn_override_init) 6211 warning_init ("initialized field overwritten"); 6212 6213 /* We can have just one union field set. */ 6214 constructor_elements = 0; 6215 } 6216 6217 /* Otherwise, output this element either to 6218 constructor_elements or to the assembler file. */ 6219 6220 celt = VEC_safe_push (constructor_elt, gc, constructor_elements, NULL); 6221 celt->index = field; 6222 celt->value = value; 6223 6224 /* Advance the variable that indicates sequential elements output. */ 6225 if (TREE_CODE (constructor_type) == ARRAY_TYPE) 6226 constructor_unfilled_index 6227 = size_binop (PLUS_EXPR, constructor_unfilled_index, 6228 bitsize_one_node); 6229 else if (TREE_CODE (constructor_type) == RECORD_TYPE) 6230 { 6231 constructor_unfilled_fields 6232 = TREE_CHAIN (constructor_unfilled_fields); 6233 6234 /* Skip any nameless bit fields. */ 6235 while (constructor_unfilled_fields != 0 6236 && DECL_C_BIT_FIELD (constructor_unfilled_fields) 6237 && DECL_NAME (constructor_unfilled_fields) == 0) 6238 constructor_unfilled_fields = 6239 TREE_CHAIN (constructor_unfilled_fields); 6240 } 6241 else if (TREE_CODE (constructor_type) == UNION_TYPE) 6242 constructor_unfilled_fields = 0; 6243 6244 /* Now output any pending elements which have become next. */ 6245 if (pending) 6246 output_pending_init_elements (0); 6247} 6248 6249/* Output any pending elements which have become next. 6250 As we output elements, constructor_unfilled_{fields,index} 6251 advances, which may cause other elements to become next; 6252 if so, they too are output. 6253 6254 If ALL is 0, we return when there are 6255 no more pending elements to output now. 6256 6257 If ALL is 1, we output space as necessary so that 6258 we can output all the pending elements. */ 6259 6260static void 6261output_pending_init_elements (int all) 6262{ 6263 struct init_node *elt = constructor_pending_elts; 6264 tree next; 6265 6266 retry: 6267 6268 /* Look through the whole pending tree. 6269 If we find an element that should be output now, 6270 output it. Otherwise, set NEXT to the element 6271 that comes first among those still pending. */ 6272 6273 next = 0; 6274 while (elt) 6275 { 6276 if (TREE_CODE (constructor_type) == ARRAY_TYPE) 6277 { 6278 if (tree_int_cst_equal (elt->purpose, 6279 constructor_unfilled_index)) 6280 output_init_element (elt->value, true, 6281 TREE_TYPE (constructor_type), 6282 constructor_unfilled_index, 0); 6283 else if (tree_int_cst_lt (constructor_unfilled_index, 6284 elt->purpose)) 6285 { 6286 /* Advance to the next smaller node. */ 6287 if (elt->left) 6288 elt = elt->left; 6289 else 6290 { 6291 /* We have reached the smallest node bigger than the 6292 current unfilled index. Fill the space first. */ 6293 next = elt->purpose; 6294 break; 6295 } 6296 } 6297 else 6298 { 6299 /* Advance to the next bigger node. */ 6300 if (elt->right) 6301 elt = elt->right; 6302 else 6303 { 6304 /* We have reached the biggest node in a subtree. Find 6305 the parent of it, which is the next bigger node. */ 6306 while (elt->parent && elt->parent->right == elt) 6307 elt = elt->parent; 6308 elt = elt->parent; 6309 if (elt && tree_int_cst_lt (constructor_unfilled_index, 6310 elt->purpose)) 6311 { 6312 next = elt->purpose; 6313 break; 6314 } 6315 } 6316 } 6317 } 6318 else if (TREE_CODE (constructor_type) == RECORD_TYPE 6319 || TREE_CODE (constructor_type) == UNION_TYPE) 6320 { 6321 tree ctor_unfilled_bitpos, elt_bitpos; 6322 6323 /* If the current record is complete we are done. */ 6324 if (constructor_unfilled_fields == 0) 6325 break; 6326 6327 ctor_unfilled_bitpos = bit_position (constructor_unfilled_fields); 6328 elt_bitpos = bit_position (elt->purpose); 6329 /* We can't compare fields here because there might be empty 6330 fields in between. */ 6331 if (tree_int_cst_equal (elt_bitpos, ctor_unfilled_bitpos)) 6332 { 6333 constructor_unfilled_fields = elt->purpose; 6334 output_init_element (elt->value, true, TREE_TYPE (elt->purpose), 6335 elt->purpose, 0); 6336 } 6337 else if (tree_int_cst_lt (ctor_unfilled_bitpos, elt_bitpos)) 6338 { 6339 /* Advance to the next smaller node. */ 6340 if (elt->left) 6341 elt = elt->left; 6342 else 6343 { 6344 /* We have reached the smallest node bigger than the 6345 current unfilled field. Fill the space first. */ 6346 next = elt->purpose; 6347 break; 6348 } 6349 } 6350 else 6351 { 6352 /* Advance to the next bigger node. */ 6353 if (elt->right) 6354 elt = elt->right; 6355 else 6356 { 6357 /* We have reached the biggest node in a subtree. Find 6358 the parent of it, which is the next bigger node. */ 6359 while (elt->parent && elt->parent->right == elt) 6360 elt = elt->parent; 6361 elt = elt->parent; 6362 if (elt 6363 && (tree_int_cst_lt (ctor_unfilled_bitpos, 6364 bit_position (elt->purpose)))) 6365 { 6366 next = elt->purpose; 6367 break; 6368 } 6369 } 6370 } 6371 } 6372 } 6373 6374 /* Ordinarily return, but not if we want to output all 6375 and there are elements left. */ 6376 if (!(all && next != 0)) 6377 return; 6378 6379 /* If it's not incremental, just skip over the gap, so that after 6380 jumping to retry we will output the next successive element. */ 6381 if (TREE_CODE (constructor_type) == RECORD_TYPE 6382 || TREE_CODE (constructor_type) == UNION_TYPE) 6383 constructor_unfilled_fields = next; 6384 else if (TREE_CODE (constructor_type) == ARRAY_TYPE) 6385 constructor_unfilled_index = next; 6386 6387 /* ELT now points to the node in the pending tree with the next 6388 initializer to output. */ 6389 goto retry; 6390} 6391 6392/* Add one non-braced element to the current constructor level. 6393 This adjusts the current position within the constructor's type. 6394 This may also start or terminate implicit levels 6395 to handle a partly-braced initializer. 6396 6397 Once this has found the correct level for the new element, 6398 it calls output_init_element. */ 6399 6400void 6401process_init_element (struct c_expr value) 6402{ 6403 tree orig_value = value.value; 6404 int string_flag = orig_value != 0 && TREE_CODE (orig_value) == STRING_CST; 6405 bool strict_string = value.original_code == STRING_CST; 6406 6407 designator_depth = 0; 6408 designator_erroneous = 0; 6409 6410 /* Handle superfluous braces around string cst as in 6411 char x[] = {"foo"}; */ 6412 if (string_flag 6413 && constructor_type 6414 && TREE_CODE (constructor_type) == ARRAY_TYPE 6415 && INTEGRAL_TYPE_P (TREE_TYPE (constructor_type)) 6416 && integer_zerop (constructor_unfilled_index)) 6417 { 6418 if (constructor_stack->replacement_value.value) 6419 error_init ("excess elements in char array initializer"); 6420 constructor_stack->replacement_value = value; 6421 return; 6422 } 6423 6424 if (constructor_stack->replacement_value.value != 0) 6425 { 6426 error_init ("excess elements in struct initializer"); 6427 return; 6428 } 6429 6430 /* Ignore elements of a brace group if it is entirely superfluous 6431 and has already been diagnosed. */ 6432 if (constructor_type == 0) 6433 return; 6434 6435 /* If we've exhausted any levels that didn't have braces, 6436 pop them now. */ 6437 while (constructor_stack->implicit) 6438 { 6439 if ((TREE_CODE (constructor_type) == RECORD_TYPE 6440 || TREE_CODE (constructor_type) == UNION_TYPE) 6441 && constructor_fields == 0) 6442 process_init_element (pop_init_level (1)); 6443 else if (TREE_CODE (constructor_type) == ARRAY_TYPE 6444 && (constructor_max_index == 0 6445 || tree_int_cst_lt (constructor_max_index, 6446 constructor_index))) 6447 process_init_element (pop_init_level (1)); 6448 else 6449 break; 6450 } 6451 6452 /* In the case of [LO ... HI] = VALUE, only evaluate VALUE once. */ 6453 if (constructor_range_stack) 6454 { 6455 /* If value is a compound literal and we'll be just using its 6456 content, don't put it into a SAVE_EXPR. */ 6457 if (TREE_CODE (value.value) != COMPOUND_LITERAL_EXPR 6458 || !require_constant_value 6459 || flag_isoc99) 6460 value.value = save_expr (value.value); 6461 } 6462 6463 while (1) 6464 { 6465 if (TREE_CODE (constructor_type) == RECORD_TYPE) 6466 { 6467 tree fieldtype; 6468 enum tree_code fieldcode; 6469 6470 if (constructor_fields == 0) 6471 { 6472 pedwarn_init ("excess elements in struct initializer"); 6473 break; 6474 } 6475 6476 fieldtype = TREE_TYPE (constructor_fields); 6477 if (fieldtype != error_mark_node) 6478 fieldtype = TYPE_MAIN_VARIANT (fieldtype); 6479 fieldcode = TREE_CODE (fieldtype); 6480 6481 /* Error for non-static initialization of a flexible array member. */ 6482 if (fieldcode == ARRAY_TYPE 6483 && !require_constant_value 6484 && TYPE_SIZE (fieldtype) == NULL_TREE 6485 && TREE_CHAIN (constructor_fields) == NULL_TREE) 6486 { 6487 error_init ("non-static initialization of a flexible array member"); 6488 break; 6489 } 6490 6491 /* Accept a string constant to initialize a subarray. */ 6492 if (value.value != 0 6493 && fieldcode == ARRAY_TYPE 6494 && INTEGRAL_TYPE_P (TREE_TYPE (fieldtype)) 6495 && string_flag) 6496 value.value = orig_value; 6497 /* Otherwise, if we have come to a subaggregate, 6498 and we don't have an element of its type, push into it. */ 6499 else if (value.value != 0 6500 && value.value != error_mark_node 6501 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != fieldtype 6502 && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE 6503 || fieldcode == UNION_TYPE)) 6504 { 6505 push_init_level (1); 6506 continue; 6507 } 6508 6509 if (value.value) 6510 { 6511 push_member_name (constructor_fields); 6512 output_init_element (value.value, strict_string, 6513 fieldtype, constructor_fields, 1); 6514 RESTORE_SPELLING_DEPTH (constructor_depth); 6515 } 6516 else 6517 /* Do the bookkeeping for an element that was 6518 directly output as a constructor. */ 6519 { 6520 /* For a record, keep track of end position of last field. */ 6521 if (DECL_SIZE (constructor_fields)) 6522 constructor_bit_index 6523 = size_binop (PLUS_EXPR, 6524 bit_position (constructor_fields), 6525 DECL_SIZE (constructor_fields)); 6526 6527 /* If the current field was the first one not yet written out, 6528 it isn't now, so update. */ 6529 if (constructor_unfilled_fields == constructor_fields) 6530 { 6531 constructor_unfilled_fields = TREE_CHAIN (constructor_fields); 6532 /* Skip any nameless bit fields. */ 6533 while (constructor_unfilled_fields != 0 6534 && DECL_C_BIT_FIELD (constructor_unfilled_fields) 6535 && DECL_NAME (constructor_unfilled_fields) == 0) 6536 constructor_unfilled_fields = 6537 TREE_CHAIN (constructor_unfilled_fields); 6538 } 6539 } 6540 6541 constructor_fields = TREE_CHAIN (constructor_fields); 6542 /* Skip any nameless bit fields at the beginning. */ 6543 while (constructor_fields != 0 6544 && DECL_C_BIT_FIELD (constructor_fields) 6545 && DECL_NAME (constructor_fields) == 0) 6546 constructor_fields = TREE_CHAIN (constructor_fields); 6547 } 6548 else if (TREE_CODE (constructor_type) == UNION_TYPE) 6549 { 6550 tree fieldtype; 6551 enum tree_code fieldcode; 6552 6553 if (constructor_fields == 0) 6554 { 6555 pedwarn_init ("excess elements in union initializer"); 6556 break; 6557 } 6558 6559 fieldtype = TREE_TYPE (constructor_fields); 6560 if (fieldtype != error_mark_node) 6561 fieldtype = TYPE_MAIN_VARIANT (fieldtype); 6562 fieldcode = TREE_CODE (fieldtype); 6563 6564 /* Warn that traditional C rejects initialization of unions. 6565 We skip the warning if the value is zero. This is done 6566 under the assumption that the zero initializer in user 6567 code appears conditioned on e.g. __STDC__ to avoid 6568 "missing initializer" warnings and relies on default 6569 initialization to zero in the traditional C case. 6570 We also skip the warning if the initializer is designated, 6571 again on the assumption that this must be conditional on 6572 __STDC__ anyway (and we've already complained about the 6573 member-designator already). */ 6574 if (!in_system_header && !constructor_designated 6575 && !(value.value && (integer_zerop (value.value) 6576 || real_zerop (value.value)))) 6577 warning (OPT_Wtraditional, "traditional C rejects initialization " 6578 "of unions"); 6579 6580 /* Accept a string constant to initialize a subarray. */ 6581 if (value.value != 0 6582 && fieldcode == ARRAY_TYPE 6583 && INTEGRAL_TYPE_P (TREE_TYPE (fieldtype)) 6584 && string_flag) 6585 value.value = orig_value; 6586 /* Otherwise, if we have come to a subaggregate, 6587 and we don't have an element of its type, push into it. */ 6588 else if (value.value != 0 6589 && value.value != error_mark_node 6590 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != fieldtype 6591 && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE 6592 || fieldcode == UNION_TYPE)) 6593 { 6594 push_init_level (1); 6595 continue; 6596 } 6597 6598 if (value.value) 6599 { 6600 push_member_name (constructor_fields); 6601 output_init_element (value.value, strict_string, 6602 fieldtype, constructor_fields, 1); 6603 RESTORE_SPELLING_DEPTH (constructor_depth); 6604 } 6605 else 6606 /* Do the bookkeeping for an element that was 6607 directly output as a constructor. */ 6608 { 6609 constructor_bit_index = DECL_SIZE (constructor_fields); 6610 constructor_unfilled_fields = TREE_CHAIN (constructor_fields); 6611 } 6612 6613 constructor_fields = 0; 6614 } 6615 else if (TREE_CODE (constructor_type) == ARRAY_TYPE) 6616 { 6617 tree elttype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type)); 6618 enum tree_code eltcode = TREE_CODE (elttype); 6619 6620 /* Accept a string constant to initialize a subarray. */ 6621 if (value.value != 0 6622 && eltcode == ARRAY_TYPE 6623 && INTEGRAL_TYPE_P (TREE_TYPE (elttype)) 6624 && string_flag) 6625 value.value = orig_value; 6626 /* Otherwise, if we have come to a subaggregate, 6627 and we don't have an element of its type, push into it. */ 6628 else if (value.value != 0 6629 && value.value != error_mark_node 6630 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != elttype 6631 && (eltcode == RECORD_TYPE || eltcode == ARRAY_TYPE 6632 || eltcode == UNION_TYPE)) 6633 { 6634 push_init_level (1); 6635 continue; 6636 } 6637 6638 if (constructor_max_index != 0 6639 && (tree_int_cst_lt (constructor_max_index, constructor_index) 6640 || integer_all_onesp (constructor_max_index))) 6641 { 6642 pedwarn_init ("excess elements in array initializer"); 6643 break; 6644 } 6645 6646 /* Now output the actual element. */ 6647 if (value.value) 6648 { 6649 push_array_bounds (tree_low_cst (constructor_index, 1)); 6650 output_init_element (value.value, strict_string, 6651 elttype, constructor_index, 1); 6652 RESTORE_SPELLING_DEPTH (constructor_depth); 6653 } 6654 6655 constructor_index 6656 = size_binop (PLUS_EXPR, constructor_index, bitsize_one_node); 6657 6658 if (!value.value) 6659 /* If we are doing the bookkeeping for an element that was 6660 directly output as a constructor, we must update 6661 constructor_unfilled_index. */ 6662 constructor_unfilled_index = constructor_index; 6663 } 6664 else if (TREE_CODE (constructor_type) == VECTOR_TYPE) 6665 { 6666 tree elttype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type)); 6667 6668 /* Do a basic check of initializer size. Note that vectors 6669 always have a fixed size derived from their type. */ 6670 if (tree_int_cst_lt (constructor_max_index, constructor_index)) 6671 { 6672 pedwarn_init ("excess elements in vector initializer"); 6673 break; 6674 } 6675 6676 /* Now output the actual element. */ 6677 if (value.value) 6678 output_init_element (value.value, strict_string, 6679 elttype, constructor_index, 1); 6680 6681 constructor_index 6682 = size_binop (PLUS_EXPR, constructor_index, bitsize_one_node); 6683 6684 if (!value.value) 6685 /* If we are doing the bookkeeping for an element that was 6686 directly output as a constructor, we must update 6687 constructor_unfilled_index. */ 6688 constructor_unfilled_index = constructor_index; 6689 } 6690 6691 /* Handle the sole element allowed in a braced initializer 6692 for a scalar variable. */ 6693 else if (constructor_type != error_mark_node 6694 && constructor_fields == 0) 6695 { 6696 pedwarn_init ("excess elements in scalar initializer"); 6697 break; 6698 } 6699 else 6700 { 6701 if (value.value) 6702 output_init_element (value.value, strict_string, 6703 constructor_type, NULL_TREE, 1); 6704 constructor_fields = 0; 6705 } 6706 6707 /* Handle range initializers either at this level or anywhere higher 6708 in the designator stack. */ 6709 if (constructor_range_stack) 6710 { 6711 struct constructor_range_stack *p, *range_stack; 6712 int finish = 0; 6713 6714 range_stack = constructor_range_stack; 6715 constructor_range_stack = 0; 6716 while (constructor_stack != range_stack->stack) 6717 { 6718 gcc_assert (constructor_stack->implicit); 6719 process_init_element (pop_init_level (1)); 6720 } 6721 for (p = range_stack; 6722 !p->range_end || tree_int_cst_equal (p->index, p->range_end); 6723 p = p->prev) 6724 { 6725 gcc_assert (constructor_stack->implicit); 6726 process_init_element (pop_init_level (1)); 6727 } 6728 6729 p->index = size_binop (PLUS_EXPR, p->index, bitsize_one_node); 6730 if (tree_int_cst_equal (p->index, p->range_end) && !p->prev) 6731 finish = 1; 6732 6733 while (1) 6734 { 6735 constructor_index = p->index; 6736 constructor_fields = p->fields; 6737 if (finish && p->range_end && p->index == p->range_start) 6738 { 6739 finish = 0; 6740 p->prev = 0; 6741 } 6742 p = p->next; 6743 if (!p) 6744 break; 6745 push_init_level (2); 6746 p->stack = constructor_stack; 6747 if (p->range_end && tree_int_cst_equal (p->index, p->range_end)) 6748 p->index = p->range_start; 6749 } 6750 6751 if (!finish) 6752 constructor_range_stack = range_stack; 6753 continue; 6754 } 6755 6756 break; 6757 } 6758 6759 constructor_range_stack = 0; 6760} 6761 6762/* Build a complete asm-statement, whose components are a CV_QUALIFIER 6763 (guaranteed to be 'volatile' or null) and ARGS (represented using 6764 an ASM_EXPR node). */ 6765tree 6766build_asm_stmt (tree cv_qualifier, tree args) 6767{ 6768 if (!ASM_VOLATILE_P (args) && cv_qualifier) 6769 ASM_VOLATILE_P (args) = 1; 6770 return add_stmt (args); 6771} 6772 6773/* Build an asm-expr, whose components are a STRING, some OUTPUTS, 6774 some INPUTS, and some CLOBBERS. The latter three may be NULL. 6775 SIMPLE indicates whether there was anything at all after the 6776 string in the asm expression -- asm("blah") and asm("blah" : ) 6777 are subtly different. We use a ASM_EXPR node to represent this. */ 6778tree 6779build_asm_expr (tree string, tree outputs, tree inputs, tree clobbers, 6780 bool simple) 6781{ 6782 tree tail; 6783 tree args; 6784 int i; 6785 const char *constraint; 6786 const char **oconstraints; 6787 bool allows_mem, allows_reg, is_inout; 6788 int ninputs, noutputs; 6789 6790 ninputs = list_length (inputs); 6791 noutputs = list_length (outputs); 6792 oconstraints = (const char **) alloca (noutputs * sizeof (const char *)); 6793 6794 string = resolve_asm_operand_names (string, outputs, inputs); 6795 6796 /* Remove output conversions that change the type but not the mode. */ 6797 for (i = 0, tail = outputs; tail; ++i, tail = TREE_CHAIN (tail)) 6798 { 6799 tree output = TREE_VALUE (tail); 6800 6801 /* ??? Really, this should not be here. Users should be using a 6802 proper lvalue, dammit. But there's a long history of using casts 6803 in the output operands. In cases like longlong.h, this becomes a 6804 primitive form of typechecking -- if the cast can be removed, then 6805 the output operand had a type of the proper width; otherwise we'll 6806 get an error. Gross, but ... */ 6807 STRIP_NOPS (output); 6808 6809 if (!lvalue_or_else (output, lv_asm)) 6810 output = error_mark_node; 6811 6812 if (output != error_mark_node 6813 && (TREE_READONLY (output) 6814 || TYPE_READONLY (TREE_TYPE (output)) 6815 || ((TREE_CODE (TREE_TYPE (output)) == RECORD_TYPE 6816 || TREE_CODE (TREE_TYPE (output)) == UNION_TYPE) 6817 && C_TYPE_FIELDS_READONLY (TREE_TYPE (output))))) 6818 readonly_error (output, lv_asm); 6819 6820 constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (tail))); 6821 oconstraints[i] = constraint; 6822 6823 if (parse_output_constraint (&constraint, i, ninputs, noutputs, 6824 &allows_mem, &allows_reg, &is_inout)) 6825 { 6826 /* If the operand is going to end up in memory, 6827 mark it addressable. */ 6828 if (!allows_reg && !c_mark_addressable (output)) 6829 output = error_mark_node; 6830 } 6831 else 6832 output = error_mark_node; 6833 6834 TREE_VALUE (tail) = output; 6835 } 6836 6837 for (i = 0, tail = inputs; tail; ++i, tail = TREE_CHAIN (tail)) 6838 { 6839 tree input; 6840 6841 constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (tail))); 6842 input = TREE_VALUE (tail); 6843 6844 if (parse_input_constraint (&constraint, i, ninputs, noutputs, 0, 6845 oconstraints, &allows_mem, &allows_reg)) 6846 { 6847 /* If the operand is going to end up in memory, 6848 mark it addressable. */ 6849 if (!allows_reg && allows_mem) 6850 { 6851 /* Strip the nops as we allow this case. FIXME, this really 6852 should be rejected or made deprecated. */ 6853 STRIP_NOPS (input); 6854 if (!c_mark_addressable (input)) 6855 input = error_mark_node; 6856 } 6857 } 6858 else 6859 input = error_mark_node; 6860 6861 TREE_VALUE (tail) = input; 6862 } 6863 6864 args = build_stmt (ASM_EXPR, string, outputs, inputs, clobbers); 6865 6866 /* asm statements without outputs, including simple ones, are treated 6867 as volatile. */ 6868 ASM_INPUT_P (args) = simple; 6869 ASM_VOLATILE_P (args) = (noutputs == 0); 6870 6871 return args; 6872} 6873 6874/* Generate a goto statement to LABEL. */ 6875 6876tree 6877c_finish_goto_label (tree label) 6878{ 6879 tree decl = lookup_label (label); 6880 if (!decl) 6881 return NULL_TREE; 6882 6883 if (C_DECL_UNJUMPABLE_STMT_EXPR (decl)) 6884 { 6885 error ("jump into statement expression"); 6886 return NULL_TREE; 6887 } 6888 6889 if (C_DECL_UNJUMPABLE_VM (decl)) 6890 { 6891 error ("jump into scope of identifier with variably modified type"); 6892 return NULL_TREE; 6893 } 6894 6895 if (!C_DECL_UNDEFINABLE_STMT_EXPR (decl)) 6896 { 6897 /* No jump from outside this statement expression context, so 6898 record that there is a jump from within this context. */ 6899 struct c_label_list *nlist; 6900 nlist = XOBNEW (&parser_obstack, struct c_label_list); 6901 nlist->next = label_context_stack_se->labels_used; 6902 nlist->label = decl; 6903 label_context_stack_se->labels_used = nlist; 6904 } 6905 6906 if (!C_DECL_UNDEFINABLE_VM (decl)) 6907 { 6908 /* No jump from outside this context context of identifiers with 6909 variably modified type, so record that there is a jump from 6910 within this context. */ 6911 struct c_label_list *nlist; 6912 nlist = XOBNEW (&parser_obstack, struct c_label_list); 6913 nlist->next = label_context_stack_vm->labels_used; 6914 nlist->label = decl; 6915 label_context_stack_vm->labels_used = nlist; 6916 } 6917 6918 TREE_USED (decl) = 1; 6919 return add_stmt (build1 (GOTO_EXPR, void_type_node, decl)); 6920} 6921 6922/* Generate a computed goto statement to EXPR. */ 6923 6924tree 6925c_finish_goto_ptr (tree expr) 6926{ 6927 if (pedantic) 6928 pedwarn ("ISO C forbids %<goto *expr;%>"); 6929 expr = convert (ptr_type_node, expr); 6930 return add_stmt (build1 (GOTO_EXPR, void_type_node, expr)); 6931} 6932 6933/* Generate a C `return' statement. RETVAL is the expression for what 6934 to return, or a null pointer for `return;' with no value. */ 6935 6936tree 6937c_finish_return (tree retval) 6938{ 6939 tree valtype = TREE_TYPE (TREE_TYPE (current_function_decl)), ret_stmt; 6940 bool no_warning = false; 6941 6942 if (TREE_THIS_VOLATILE (current_function_decl)) 6943 warning (0, "function declared %<noreturn%> has a %<return%> statement"); 6944 6945 if (!retval) 6946 { 6947 current_function_returns_null = 1; 6948 if ((warn_return_type || flag_isoc99) 6949 && valtype != 0 && TREE_CODE (valtype) != VOID_TYPE) 6950 { 6951 pedwarn_c99 ("%<return%> with no value, in " 6952 "function returning non-void"); 6953 no_warning = true; 6954 } 6955 } 6956 else if (valtype == 0 || TREE_CODE (valtype) == VOID_TYPE) 6957 { 6958 current_function_returns_null = 1; 6959 if (pedantic || TREE_CODE (TREE_TYPE (retval)) != VOID_TYPE) 6960 pedwarn ("%<return%> with a value, in function returning void"); 6961 } 6962 else 6963 { 6964 tree t = convert_for_assignment (valtype, retval, ic_return, 6965 NULL_TREE, NULL_TREE, 0); 6966 tree res = DECL_RESULT (current_function_decl); 6967 tree inner; 6968 6969 current_function_returns_value = 1; 6970 if (t == error_mark_node) 6971 return NULL_TREE; 6972 6973 inner = t = convert (TREE_TYPE (res), t); 6974 6975 /* Strip any conversions, additions, and subtractions, and see if 6976 we are returning the address of a local variable. Warn if so. */ 6977 while (1) 6978 { 6979 switch (TREE_CODE (inner)) 6980 { 6981 case NOP_EXPR: case NON_LVALUE_EXPR: case CONVERT_EXPR: 6982 case PLUS_EXPR: 6983 inner = TREE_OPERAND (inner, 0); 6984 continue; 6985 6986 case MINUS_EXPR: 6987 /* If the second operand of the MINUS_EXPR has a pointer 6988 type (or is converted from it), this may be valid, so 6989 don't give a warning. */ 6990 { 6991 tree op1 = TREE_OPERAND (inner, 1); 6992 6993 while (!POINTER_TYPE_P (TREE_TYPE (op1)) 6994 && (TREE_CODE (op1) == NOP_EXPR 6995 || TREE_CODE (op1) == NON_LVALUE_EXPR 6996 || TREE_CODE (op1) == CONVERT_EXPR)) 6997 op1 = TREE_OPERAND (op1, 0); 6998 6999 if (POINTER_TYPE_P (TREE_TYPE (op1))) 7000 break; 7001 7002 inner = TREE_OPERAND (inner, 0); 7003 continue; 7004 } 7005 7006 case ADDR_EXPR: 7007 inner = TREE_OPERAND (inner, 0); 7008 7009 while (REFERENCE_CLASS_P (inner) 7010 && TREE_CODE (inner) != INDIRECT_REF) 7011 inner = TREE_OPERAND (inner, 0); 7012 7013 if (DECL_P (inner) 7014 && !DECL_EXTERNAL (inner) 7015 && !TREE_STATIC (inner) 7016 && DECL_CONTEXT (inner) == current_function_decl) 7017 warning (0, "function returns address of local variable"); 7018 break; 7019 7020 default: 7021 break; 7022 } 7023 7024 break; 7025 } 7026 7027 retval = build2 (MODIFY_EXPR, TREE_TYPE (res), res, t); 7028 } 7029 7030 ret_stmt = build_stmt (RETURN_EXPR, retval); 7031 TREE_NO_WARNING (ret_stmt) |= no_warning; 7032 return add_stmt (ret_stmt); 7033} 7034 7035struct c_switch { 7036 /* The SWITCH_EXPR being built. */ 7037 tree switch_expr; 7038 7039 /* The original type of the testing expression, i.e. before the 7040 default conversion is applied. */ 7041 tree orig_type; 7042 7043 /* A splay-tree mapping the low element of a case range to the high 7044 element, or NULL_TREE if there is no high element. Used to 7045 determine whether or not a new case label duplicates an old case 7046 label. We need a tree, rather than simply a hash table, because 7047 of the GNU case range extension. */ 7048 splay_tree cases; 7049 7050 /* Number of nested statement expressions within this switch 7051 statement; if nonzero, case and default labels may not 7052 appear. */ 7053 unsigned int blocked_stmt_expr; 7054 7055 /* Scope of outermost declarations of identifiers with variably 7056 modified type within this switch statement; if nonzero, case and 7057 default labels may not appear. */ 7058 unsigned int blocked_vm; 7059 7060 /* The next node on the stack. */ 7061 struct c_switch *next; 7062}; 7063 7064/* A stack of the currently active switch statements. The innermost 7065 switch statement is on the top of the stack. There is no need to 7066 mark the stack for garbage collection because it is only active 7067 during the processing of the body of a function, and we never 7068 collect at that point. */ 7069 7070struct c_switch *c_switch_stack; 7071 7072/* Start a C switch statement, testing expression EXP. Return the new 7073 SWITCH_EXPR. */ 7074 7075tree 7076c_start_case (tree exp) 7077{ 7078 tree orig_type = error_mark_node; 7079 struct c_switch *cs; 7080 7081 if (exp != error_mark_node) 7082 { 7083 orig_type = TREE_TYPE (exp); 7084 7085 if (!INTEGRAL_TYPE_P (orig_type)) 7086 { 7087 if (orig_type != error_mark_node) 7088 { 7089 error ("switch quantity not an integer"); 7090 orig_type = error_mark_node; 7091 } 7092 exp = integer_zero_node; 7093 } 7094 else 7095 { 7096 tree type = TYPE_MAIN_VARIANT (orig_type); 7097 7098 if (!in_system_header 7099 && (type == long_integer_type_node 7100 || type == long_unsigned_type_node)) 7101 warning (OPT_Wtraditional, "%<long%> switch expression not " 7102 "converted to %<int%> in ISO C"); 7103 7104 exp = default_conversion (exp); 7105 } 7106 } 7107 7108 /* Add this new SWITCH_EXPR to the stack. */ 7109 cs = XNEW (struct c_switch); 7110 cs->switch_expr = build3 (SWITCH_EXPR, orig_type, exp, NULL_TREE, NULL_TREE); 7111 cs->orig_type = orig_type; 7112 cs->cases = splay_tree_new (case_compare, NULL, NULL); 7113 cs->blocked_stmt_expr = 0; 7114 cs->blocked_vm = 0; 7115 cs->next = c_switch_stack; 7116 c_switch_stack = cs; 7117 7118 return add_stmt (cs->switch_expr); 7119} 7120 7121/* Process a case label. */ 7122 7123tree 7124do_case (tree low_value, tree high_value) 7125{ 7126 tree label = NULL_TREE; 7127 7128 if (c_switch_stack && !c_switch_stack->blocked_stmt_expr 7129 && !c_switch_stack->blocked_vm) 7130 { 7131 label = c_add_case_label (c_switch_stack->cases, 7132 SWITCH_COND (c_switch_stack->switch_expr), 7133 c_switch_stack->orig_type, 7134 low_value, high_value); 7135 if (label == error_mark_node) 7136 label = NULL_TREE; 7137 } 7138 else if (c_switch_stack && c_switch_stack->blocked_stmt_expr) 7139 { 7140 if (low_value) 7141 error ("case label in statement expression not containing " 7142 "enclosing switch statement"); 7143 else 7144 error ("%<default%> label in statement expression not containing " 7145 "enclosing switch statement"); 7146 } 7147 else if (c_switch_stack && c_switch_stack->blocked_vm) 7148 { 7149 if (low_value) 7150 error ("case label in scope of identifier with variably modified " 7151 "type not containing enclosing switch statement"); 7152 else 7153 error ("%<default%> label in scope of identifier with variably " 7154 "modified type not containing enclosing switch statement"); 7155 } 7156 else if (low_value) 7157 error ("case label not within a switch statement"); 7158 else 7159 error ("%<default%> label not within a switch statement"); 7160 7161 return label; 7162} 7163 7164/* Finish the switch statement. */ 7165 7166void 7167c_finish_case (tree body) 7168{ 7169 struct c_switch *cs = c_switch_stack; 7170 location_t switch_location; 7171 7172 SWITCH_BODY (cs->switch_expr) = body; 7173 7174 /* We must not be within a statement expression nested in the switch 7175 at this point; we might, however, be within the scope of an 7176 identifier with variably modified type nested in the switch. */ 7177 gcc_assert (!cs->blocked_stmt_expr); 7178 7179 /* Emit warnings as needed. */ 7180 if (EXPR_HAS_LOCATION (cs->switch_expr)) 7181 switch_location = EXPR_LOCATION (cs->switch_expr); 7182 else 7183 switch_location = input_location; 7184 c_do_switch_warnings (cs->cases, switch_location, 7185 TREE_TYPE (cs->switch_expr), 7186 SWITCH_COND (cs->switch_expr)); 7187 7188 /* Pop the stack. */ 7189 c_switch_stack = cs->next; 7190 splay_tree_delete (cs->cases); 7191 XDELETE (cs); 7192} 7193 7194/* Emit an if statement. IF_LOCUS is the location of the 'if'. COND, 7195 THEN_BLOCK and ELSE_BLOCK are expressions to be used; ELSE_BLOCK 7196 may be null. NESTED_IF is true if THEN_BLOCK contains another IF 7197 statement, and was not surrounded with parenthesis. */ 7198 7199void 7200c_finish_if_stmt (location_t if_locus, tree cond, tree then_block, 7201 tree else_block, bool nested_if) 7202{ 7203 tree stmt; 7204 7205 /* Diagnose an ambiguous else if if-then-else is nested inside if-then. */ 7206 if (warn_parentheses && nested_if && else_block == NULL) 7207 { 7208 tree inner_if = then_block; 7209 7210 /* We know from the grammar productions that there is an IF nested 7211 within THEN_BLOCK. Due to labels and c99 conditional declarations, 7212 it might not be exactly THEN_BLOCK, but should be the last 7213 non-container statement within. */ 7214 while (1) 7215 switch (TREE_CODE (inner_if)) 7216 { 7217 case COND_EXPR: 7218 goto found; 7219 case BIND_EXPR: 7220 inner_if = BIND_EXPR_BODY (inner_if); 7221 break; 7222 case STATEMENT_LIST: 7223 inner_if = expr_last (then_block); 7224 break; 7225 case TRY_FINALLY_EXPR: 7226 case TRY_CATCH_EXPR: 7227 inner_if = TREE_OPERAND (inner_if, 0); 7228 break; 7229 default: 7230 gcc_unreachable (); 7231 } 7232 found: 7233 7234 if (COND_EXPR_ELSE (inner_if)) 7235 warning (OPT_Wparentheses, 7236 "%Hsuggest explicit braces to avoid ambiguous %<else%>", 7237 &if_locus); 7238 } 7239 7240 empty_body_warning (then_block, else_block); 7241 7242 stmt = build3 (COND_EXPR, void_type_node, cond, then_block, else_block); 7243 SET_EXPR_LOCATION (stmt, if_locus); 7244 add_stmt (stmt); 7245} 7246 7247/* Emit a general-purpose loop construct. START_LOCUS is the location of 7248 the beginning of the loop. COND is the loop condition. COND_IS_FIRST 7249 is false for DO loops. INCR is the FOR increment expression. BODY is 7250 the statement controlled by the loop. BLAB is the break label. CLAB is 7251 the continue label. Everything is allowed to be NULL. */ 7252 7253void 7254c_finish_loop (location_t start_locus, tree cond, tree incr, tree body, 7255 tree blab, tree clab, bool cond_is_first) 7256{ 7257 tree entry = NULL, exit = NULL, t; 7258 7259 /* If the condition is zero don't generate a loop construct. */ 7260 if (cond && integer_zerop (cond)) 7261 { 7262 if (cond_is_first) 7263 { 7264 t = build_and_jump (&blab); 7265 SET_EXPR_LOCATION (t, start_locus); 7266 add_stmt (t); 7267 } 7268 } 7269 else 7270 { 7271 tree top = build1 (LABEL_EXPR, void_type_node, NULL_TREE); 7272 7273 /* If we have an exit condition, then we build an IF with gotos either 7274 out of the loop, or to the top of it. If there's no exit condition, 7275 then we just build a jump back to the top. */ 7276 exit = build_and_jump (&LABEL_EXPR_LABEL (top)); 7277 7278 if (cond && !integer_nonzerop (cond)) 7279 { 7280 /* Canonicalize the loop condition to the end. This means 7281 generating a branch to the loop condition. Reuse the 7282 continue label, if possible. */ 7283 if (cond_is_first) 7284 { 7285 if (incr || !clab) 7286 { 7287 entry = build1 (LABEL_EXPR, void_type_node, NULL_TREE); 7288 t = build_and_jump (&LABEL_EXPR_LABEL (entry)); 7289 } 7290 else 7291 t = build1 (GOTO_EXPR, void_type_node, clab); 7292 SET_EXPR_LOCATION (t, start_locus); 7293 add_stmt (t); 7294 } 7295 7296 t = build_and_jump (&blab); 7297 exit = fold_build3 (COND_EXPR, void_type_node, cond, exit, t); 7298 if (cond_is_first) 7299 SET_EXPR_LOCATION (exit, start_locus); 7300 else 7301 SET_EXPR_LOCATION (exit, input_location); 7302 } 7303 7304 add_stmt (top); 7305 } 7306 7307 if (body) 7308 add_stmt (body); 7309 if (clab) 7310 add_stmt (build1 (LABEL_EXPR, void_type_node, clab)); 7311 if (incr) 7312 add_stmt (incr); 7313 if (entry) 7314 add_stmt (entry); 7315 if (exit) 7316 add_stmt (exit); 7317 if (blab) 7318 add_stmt (build1 (LABEL_EXPR, void_type_node, blab)); 7319} 7320 7321tree 7322c_finish_bc_stmt (tree *label_p, bool is_break) 7323{ 7324 bool skip; 7325 tree label = *label_p; 7326 7327 /* In switch statements break is sometimes stylistically used after 7328 a return statement. This can lead to spurious warnings about 7329 control reaching the end of a non-void function when it is 7330 inlined. Note that we are calling block_may_fallthru with 7331 language specific tree nodes; this works because 7332 block_may_fallthru returns true when given something it does not 7333 understand. */ 7334 skip = !block_may_fallthru (cur_stmt_list); 7335 7336 if (!label) 7337 { 7338 if (!skip) 7339 *label_p = label = create_artificial_label (); 7340 } 7341 else if (TREE_CODE (label) == LABEL_DECL) 7342 ; 7343 else switch (TREE_INT_CST_LOW (label)) 7344 { 7345 case 0: 7346 if (is_break) 7347 error ("break statement not within loop or switch"); 7348 else 7349 error ("continue statement not within a loop"); 7350 return NULL_TREE; 7351 7352 case 1: 7353 gcc_assert (is_break); 7354 error ("break statement used with OpenMP for loop"); 7355 return NULL_TREE; 7356 7357 default: 7358 gcc_unreachable (); 7359 } 7360 7361 if (skip) 7362 return NULL_TREE; 7363 7364 return add_stmt (build1 (GOTO_EXPR, void_type_node, label)); 7365} 7366 7367/* A helper routine for c_process_expr_stmt and c_finish_stmt_expr. */ 7368 7369static void 7370emit_side_effect_warnings (tree expr) 7371{ 7372 if (expr == error_mark_node) 7373 ; 7374 else if (!TREE_SIDE_EFFECTS (expr)) 7375 { 7376 if (!VOID_TYPE_P (TREE_TYPE (expr)) && !TREE_NO_WARNING (expr)) 7377 warning (0, "%Hstatement with no effect", 7378 EXPR_HAS_LOCATION (expr) ? EXPR_LOCUS (expr) : &input_location); 7379 } 7380 else if (warn_unused_value) 7381 warn_if_unused_value (expr, input_location); 7382} 7383 7384/* Process an expression as if it were a complete statement. Emit 7385 diagnostics, but do not call ADD_STMT. */ 7386 7387tree 7388c_process_expr_stmt (tree expr) 7389{ 7390 if (!expr) 7391 return NULL_TREE; 7392 7393 if (warn_sequence_point) 7394 verify_sequence_points (expr); 7395 7396 if (TREE_TYPE (expr) != error_mark_node 7397 && !COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (expr)) 7398 && TREE_CODE (TREE_TYPE (expr)) != ARRAY_TYPE) 7399 error ("expression statement has incomplete type"); 7400 7401 /* If we're not processing a statement expression, warn about unused values. 7402 Warnings for statement expressions will be emitted later, once we figure 7403 out which is the result. */ 7404 if (!STATEMENT_LIST_STMT_EXPR (cur_stmt_list) 7405 && (extra_warnings || warn_unused_value)) 7406 emit_side_effect_warnings (expr); 7407 7408 /* If the expression is not of a type to which we cannot assign a line 7409 number, wrap the thing in a no-op NOP_EXPR. */ 7410 if (DECL_P (expr) || CONSTANT_CLASS_P (expr)) 7411 expr = build1 (NOP_EXPR, TREE_TYPE (expr), expr); 7412 7413 if (EXPR_P (expr)) 7414 SET_EXPR_LOCATION (expr, input_location); 7415 7416 return expr; 7417} 7418 7419/* Emit an expression as a statement. */ 7420 7421tree 7422c_finish_expr_stmt (tree expr) 7423{ 7424 if (expr) 7425 return add_stmt (c_process_expr_stmt (expr)); 7426 else 7427 return NULL; 7428} 7429 7430/* Do the opposite and emit a statement as an expression. To begin, 7431 create a new binding level and return it. */ 7432 7433tree 7434c_begin_stmt_expr (void) 7435{ 7436 tree ret; 7437 struct c_label_context_se *nstack; 7438 struct c_label_list *glist; 7439 7440 /* We must force a BLOCK for this level so that, if it is not expanded 7441 later, there is a way to turn off the entire subtree of blocks that 7442 are contained in it. */ 7443 keep_next_level (); 7444 ret = c_begin_compound_stmt (true); 7445 if (c_switch_stack) 7446 { 7447 c_switch_stack->blocked_stmt_expr++; 7448 gcc_assert (c_switch_stack->blocked_stmt_expr != 0); 7449 } 7450 for (glist = label_context_stack_se->labels_used; 7451 glist != NULL; 7452 glist = glist->next) 7453 { 7454 C_DECL_UNDEFINABLE_STMT_EXPR (glist->label) = 1; 7455 } 7456 nstack = XOBNEW (&parser_obstack, struct c_label_context_se); 7457 nstack->labels_def = NULL; 7458 nstack->labels_used = NULL; 7459 nstack->next = label_context_stack_se; 7460 label_context_stack_se = nstack; 7461 7462 /* Mark the current statement list as belonging to a statement list. */ 7463 STATEMENT_LIST_STMT_EXPR (ret) = 1; 7464 7465 return ret; 7466} 7467 7468tree 7469c_finish_stmt_expr (tree body) 7470{ 7471 tree last, type, tmp, val; 7472 tree *last_p; 7473 struct c_label_list *dlist, *glist, *glist_prev = NULL; 7474 7475 body = c_end_compound_stmt (body, true); 7476 if (c_switch_stack) 7477 { 7478 gcc_assert (c_switch_stack->blocked_stmt_expr != 0); 7479 c_switch_stack->blocked_stmt_expr--; 7480 } 7481 /* It is no longer possible to jump to labels defined within this 7482 statement expression. */ 7483 for (dlist = label_context_stack_se->labels_def; 7484 dlist != NULL; 7485 dlist = dlist->next) 7486 { 7487 C_DECL_UNJUMPABLE_STMT_EXPR (dlist->label) = 1; 7488 } 7489 /* It is again possible to define labels with a goto just outside 7490 this statement expression. */ 7491 for (glist = label_context_stack_se->next->labels_used; 7492 glist != NULL; 7493 glist = glist->next) 7494 { 7495 C_DECL_UNDEFINABLE_STMT_EXPR (glist->label) = 0; 7496 glist_prev = glist; 7497 } 7498 if (glist_prev != NULL) 7499 glist_prev->next = label_context_stack_se->labels_used; 7500 else 7501 label_context_stack_se->next->labels_used 7502 = label_context_stack_se->labels_used; 7503 label_context_stack_se = label_context_stack_se->next; 7504 7505 /* Locate the last statement in BODY. See c_end_compound_stmt 7506 about always returning a BIND_EXPR. */ 7507 last_p = &BIND_EXPR_BODY (body); 7508 last = BIND_EXPR_BODY (body); 7509 7510 continue_searching: 7511 if (TREE_CODE (last) == STATEMENT_LIST) 7512 { 7513 tree_stmt_iterator i; 7514 7515 /* This can happen with degenerate cases like ({ }). No value. */ 7516 if (!TREE_SIDE_EFFECTS (last)) 7517 return body; 7518 7519 /* If we're supposed to generate side effects warnings, process 7520 all of the statements except the last. */ 7521 if (extra_warnings || warn_unused_value) 7522 { 7523 for (i = tsi_start (last); !tsi_one_before_end_p (i); tsi_next (&i)) 7524 emit_side_effect_warnings (tsi_stmt (i)); 7525 } 7526 else 7527 i = tsi_last (last); 7528 last_p = tsi_stmt_ptr (i); 7529 last = *last_p; 7530 } 7531 7532 /* If the end of the list is exception related, then the list was split 7533 by a call to push_cleanup. Continue searching. */ 7534 if (TREE_CODE (last) == TRY_FINALLY_EXPR 7535 || TREE_CODE (last) == TRY_CATCH_EXPR) 7536 { 7537 last_p = &TREE_OPERAND (last, 0); 7538 last = *last_p; 7539 goto continue_searching; 7540 } 7541 7542 /* In the case that the BIND_EXPR is not necessary, return the 7543 expression out from inside it. */ 7544 if (last == error_mark_node 7545 || (last == BIND_EXPR_BODY (body) 7546 && BIND_EXPR_VARS (body) == NULL)) 7547 { 7548 /* Do not warn if the return value of a statement expression is 7549 unused. */ 7550 if (EXPR_P (last)) 7551 TREE_NO_WARNING (last) = 1; 7552 return last; 7553 } 7554 7555 /* Extract the type of said expression. */ 7556 type = TREE_TYPE (last); 7557 7558 /* If we're not returning a value at all, then the BIND_EXPR that 7559 we already have is a fine expression to return. */ 7560 if (!type || VOID_TYPE_P (type)) 7561 return body; 7562 7563 /* Now that we've located the expression containing the value, it seems 7564 silly to make voidify_wrapper_expr repeat the process. Create a 7565 temporary of the appropriate type and stick it in a TARGET_EXPR. */ 7566 tmp = create_tmp_var_raw (type, NULL); 7567 7568 /* Unwrap a no-op NOP_EXPR as added by c_finish_expr_stmt. This avoids 7569 tree_expr_nonnegative_p giving up immediately. */ 7570 val = last; 7571 if (TREE_CODE (val) == NOP_EXPR 7572 && TREE_TYPE (val) == TREE_TYPE (TREE_OPERAND (val, 0))) 7573 val = TREE_OPERAND (val, 0); 7574 7575 *last_p = build2 (MODIFY_EXPR, void_type_node, tmp, val); 7576 SET_EXPR_LOCUS (*last_p, EXPR_LOCUS (last)); 7577 7578 return build4 (TARGET_EXPR, type, tmp, body, NULL_TREE, NULL_TREE); 7579} 7580 7581/* Begin the scope of an identifier of variably modified type, scope 7582 number SCOPE. Jumping from outside this scope to inside it is not 7583 permitted. */ 7584 7585void 7586c_begin_vm_scope (unsigned int scope) 7587{ 7588 struct c_label_context_vm *nstack; 7589 struct c_label_list *glist; 7590 7591 gcc_assert (scope > 0); 7592 7593 /* At file_scope, we don't have to do any processing. */ 7594 if (label_context_stack_vm == NULL) 7595 return; 7596 7597 if (c_switch_stack && !c_switch_stack->blocked_vm) 7598 c_switch_stack->blocked_vm = scope; 7599 for (glist = label_context_stack_vm->labels_used; 7600 glist != NULL; 7601 glist = glist->next) 7602 { 7603 C_DECL_UNDEFINABLE_VM (glist->label) = 1; 7604 } 7605 nstack = XOBNEW (&parser_obstack, struct c_label_context_vm); 7606 nstack->labels_def = NULL; 7607 nstack->labels_used = NULL; 7608 nstack->scope = scope; 7609 nstack->next = label_context_stack_vm; 7610 label_context_stack_vm = nstack; 7611} 7612 7613/* End a scope which may contain identifiers of variably modified 7614 type, scope number SCOPE. */ 7615 7616void 7617c_end_vm_scope (unsigned int scope) 7618{ 7619 if (label_context_stack_vm == NULL) 7620 return; 7621 if (c_switch_stack && c_switch_stack->blocked_vm == scope) 7622 c_switch_stack->blocked_vm = 0; 7623 /* We may have a number of nested scopes of identifiers with 7624 variably modified type, all at this depth. Pop each in turn. */ 7625 while (label_context_stack_vm->scope == scope) 7626 { 7627 struct c_label_list *dlist, *glist, *glist_prev = NULL; 7628 7629 /* It is no longer possible to jump to labels defined within this 7630 scope. */ 7631 for (dlist = label_context_stack_vm->labels_def; 7632 dlist != NULL; 7633 dlist = dlist->next) 7634 { 7635 C_DECL_UNJUMPABLE_VM (dlist->label) = 1; 7636 } 7637 /* It is again possible to define labels with a goto just outside 7638 this scope. */ 7639 for (glist = label_context_stack_vm->next->labels_used; 7640 glist != NULL; 7641 glist = glist->next) 7642 { 7643 C_DECL_UNDEFINABLE_VM (glist->label) = 0; 7644 glist_prev = glist; 7645 } 7646 if (glist_prev != NULL) 7647 glist_prev->next = label_context_stack_vm->labels_used; 7648 else 7649 label_context_stack_vm->next->labels_used 7650 = label_context_stack_vm->labels_used; 7651 label_context_stack_vm = label_context_stack_vm->next; 7652 } 7653} 7654 7655/* Begin and end compound statements. This is as simple as pushing 7656 and popping new statement lists from the tree. */ 7657 7658tree 7659c_begin_compound_stmt (bool do_scope) 7660{ 7661 tree stmt = push_stmt_list (); 7662 if (do_scope) 7663 push_scope (); 7664 return stmt; 7665} 7666 7667tree 7668c_end_compound_stmt (tree stmt, bool do_scope) 7669{ 7670 tree block = NULL; 7671 7672 if (do_scope) 7673 { 7674 if (c_dialect_objc ()) 7675 objc_clear_super_receiver (); 7676 block = pop_scope (); 7677 } 7678 7679 stmt = pop_stmt_list (stmt); 7680 stmt = c_build_bind_expr (block, stmt); 7681 7682 /* If this compound statement is nested immediately inside a statement 7683 expression, then force a BIND_EXPR to be created. Otherwise we'll 7684 do the wrong thing for ({ { 1; } }) or ({ 1; { } }). In particular, 7685 STATEMENT_LISTs merge, and thus we can lose track of what statement 7686 was really last. */ 7687 if (cur_stmt_list 7688 && STATEMENT_LIST_STMT_EXPR (cur_stmt_list) 7689 && TREE_CODE (stmt) != BIND_EXPR) 7690 { 7691 stmt = build3 (BIND_EXPR, void_type_node, NULL, stmt, NULL); 7692 TREE_SIDE_EFFECTS (stmt) = 1; 7693 } 7694 7695 return stmt; 7696} 7697 7698/* Queue a cleanup. CLEANUP is an expression/statement to be executed 7699 when the current scope is exited. EH_ONLY is true when this is not 7700 meant to apply to normal control flow transfer. */ 7701 7702void 7703push_cleanup (tree ARG_UNUSED (decl), tree cleanup, bool eh_only) 7704{ 7705 enum tree_code code; 7706 tree stmt, list; 7707 bool stmt_expr; 7708 7709 code = eh_only ? TRY_CATCH_EXPR : TRY_FINALLY_EXPR; 7710 stmt = build_stmt (code, NULL, cleanup); 7711 add_stmt (stmt); 7712 stmt_expr = STATEMENT_LIST_STMT_EXPR (cur_stmt_list); 7713 list = push_stmt_list (); 7714 TREE_OPERAND (stmt, 0) = list; 7715 STATEMENT_LIST_STMT_EXPR (list) = stmt_expr; 7716} 7717 7718/* Build a binary-operation expression without default conversions. 7719 CODE is the kind of expression to build. 7720 This function differs from `build' in several ways: 7721 the data type of the result is computed and recorded in it, 7722 warnings are generated if arg data types are invalid, 7723 special handling for addition and subtraction of pointers is known, 7724 and some optimization is done (operations on narrow ints 7725 are done in the narrower type when that gives the same result). 7726 Constant folding is also done before the result is returned. 7727 7728 Note that the operands will never have enumeral types, or function 7729 or array types, because either they will have the default conversions 7730 performed or they have both just been converted to some other type in which 7731 the arithmetic is to be done. */ 7732 7733tree 7734build_binary_op (enum tree_code code, tree orig_op0, tree orig_op1, 7735 int convert_p) 7736{ 7737 tree type0, type1; 7738 enum tree_code code0, code1; 7739 tree op0, op1; 7740 const char *invalid_op_diag; 7741 7742 /* Expression code to give to the expression when it is built. 7743 Normally this is CODE, which is what the caller asked for, 7744 but in some special cases we change it. */ 7745 enum tree_code resultcode = code; 7746 7747 /* Data type in which the computation is to be performed. 7748 In the simplest cases this is the common type of the arguments. */ 7749 tree result_type = NULL; 7750 7751 /* Nonzero means operands have already been type-converted 7752 in whatever way is necessary. 7753 Zero means they need to be converted to RESULT_TYPE. */ 7754 int converted = 0; 7755 7756 /* Nonzero means create the expression with this type, rather than 7757 RESULT_TYPE. */ 7758 tree build_type = 0; 7759 7760 /* Nonzero means after finally constructing the expression 7761 convert it to this type. */ 7762 tree final_type = 0; 7763 7764 /* Nonzero if this is an operation like MIN or MAX which can 7765 safely be computed in short if both args are promoted shorts. 7766 Also implies COMMON. 7767 -1 indicates a bitwise operation; this makes a difference 7768 in the exact conditions for when it is safe to do the operation 7769 in a narrower mode. */ 7770 int shorten = 0; 7771 7772 /* Nonzero if this is a comparison operation; 7773 if both args are promoted shorts, compare the original shorts. 7774 Also implies COMMON. */ 7775 int short_compare = 0; 7776 7777 /* Nonzero if this is a right-shift operation, which can be computed on the 7778 original short and then promoted if the operand is a promoted short. */ 7779 int short_shift = 0; 7780 7781 /* Nonzero means set RESULT_TYPE to the common type of the args. */ 7782 int common = 0; 7783 7784 /* True means types are compatible as far as ObjC is concerned. */ 7785 bool objc_ok; 7786 7787 if (convert_p) 7788 { 7789 op0 = default_conversion (orig_op0); 7790 op1 = default_conversion (orig_op1); 7791 } 7792 else 7793 { 7794 op0 = orig_op0; 7795 op1 = orig_op1; 7796 } 7797 7798 type0 = TREE_TYPE (op0); 7799 type1 = TREE_TYPE (op1); 7800 7801 /* The expression codes of the data types of the arguments tell us 7802 whether the arguments are integers, floating, pointers, etc. */ 7803 code0 = TREE_CODE (type0); 7804 code1 = TREE_CODE (type1); 7805 7806 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */ 7807 STRIP_TYPE_NOPS (op0); 7808 STRIP_TYPE_NOPS (op1); 7809 7810 /* If an error was already reported for one of the arguments, 7811 avoid reporting another error. */ 7812 7813 if (code0 == ERROR_MARK || code1 == ERROR_MARK) 7814 return error_mark_node; 7815 7816 if ((invalid_op_diag 7817 = targetm.invalid_binary_op (code, type0, type1))) 7818 { 7819 error (invalid_op_diag); 7820 return error_mark_node; 7821 } 7822 7823 objc_ok = objc_compare_types (type0, type1, -3, NULL_TREE); 7824 7825 switch (code) 7826 { 7827 case PLUS_EXPR: 7828 /* Handle the pointer + int case. */ 7829 if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE) 7830 return pointer_int_sum (PLUS_EXPR, op0, op1); 7831 else if (code1 == POINTER_TYPE && code0 == INTEGER_TYPE) 7832 return pointer_int_sum (PLUS_EXPR, op1, op0); 7833 else 7834 common = 1; 7835 break; 7836 7837 case MINUS_EXPR: 7838 /* Subtraction of two similar pointers. 7839 We must subtract them as integers, then divide by object size. */ 7840 if (code0 == POINTER_TYPE && code1 == POINTER_TYPE 7841 && comp_target_types (type0, type1)) 7842 return pointer_diff (op0, op1); 7843 /* Handle pointer minus int. Just like pointer plus int. */ 7844 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE) 7845 return pointer_int_sum (MINUS_EXPR, op0, op1); 7846 else 7847 common = 1; 7848 break; 7849 7850 case MULT_EXPR: 7851 common = 1; 7852 break; 7853 7854 case TRUNC_DIV_EXPR: 7855 case CEIL_DIV_EXPR: 7856 case FLOOR_DIV_EXPR: 7857 case ROUND_DIV_EXPR: 7858 case EXACT_DIV_EXPR: 7859 /* Floating point division by zero is a legitimate way to obtain 7860 infinities and NaNs. */ 7861 if (skip_evaluation == 0 && integer_zerop (op1)) 7862 warning (OPT_Wdiv_by_zero, "division by zero"); 7863 7864 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE 7865 || code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE) 7866 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE 7867 || code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE)) 7868 { 7869 enum tree_code tcode0 = code0, tcode1 = code1; 7870 7871 if (code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE) 7872 tcode0 = TREE_CODE (TREE_TYPE (TREE_TYPE (op0))); 7873 if (code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE) 7874 tcode1 = TREE_CODE (TREE_TYPE (TREE_TYPE (op1))); 7875 7876 if (!(tcode0 == INTEGER_TYPE && tcode1 == INTEGER_TYPE)) 7877 resultcode = RDIV_EXPR; 7878 else 7879 /* Although it would be tempting to shorten always here, that 7880 loses on some targets, since the modulo instruction is 7881 undefined if the quotient can't be represented in the 7882 computation mode. We shorten only if unsigned or if 7883 dividing by something we know != -1. */ 7884 shorten = (TYPE_UNSIGNED (TREE_TYPE (orig_op0)) 7885 || (TREE_CODE (op1) == INTEGER_CST 7886 && !integer_all_onesp (op1))); 7887 common = 1; 7888 } 7889 break; 7890 7891 case BIT_AND_EXPR: 7892 case BIT_IOR_EXPR: 7893 case BIT_XOR_EXPR: 7894 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE) 7895 shorten = -1; 7896 else if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE) 7897 common = 1; 7898 break; 7899 7900 case TRUNC_MOD_EXPR: 7901 case FLOOR_MOD_EXPR: 7902 if (skip_evaluation == 0 && integer_zerop (op1)) 7903 warning (OPT_Wdiv_by_zero, "division by zero"); 7904 7905 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE) 7906 { 7907 /* Although it would be tempting to shorten always here, that loses 7908 on some targets, since the modulo instruction is undefined if the 7909 quotient can't be represented in the computation mode. We shorten 7910 only if unsigned or if dividing by something we know != -1. */ 7911 shorten = (TYPE_UNSIGNED (TREE_TYPE (orig_op0)) 7912 || (TREE_CODE (op1) == INTEGER_CST 7913 && !integer_all_onesp (op1))); 7914 common = 1; 7915 } 7916 break; 7917 7918 case TRUTH_ANDIF_EXPR: 7919 case TRUTH_ORIF_EXPR: 7920 case TRUTH_AND_EXPR: 7921 case TRUTH_OR_EXPR: 7922 case TRUTH_XOR_EXPR: 7923 if ((code0 == INTEGER_TYPE || code0 == POINTER_TYPE 7924 || code0 == REAL_TYPE || code0 == COMPLEX_TYPE) 7925 && (code1 == INTEGER_TYPE || code1 == POINTER_TYPE 7926 || code1 == REAL_TYPE || code1 == COMPLEX_TYPE)) 7927 { 7928 /* Result of these operations is always an int, 7929 but that does not mean the operands should be 7930 converted to ints! */ 7931 result_type = integer_type_node; 7932 op0 = c_common_truthvalue_conversion (op0); 7933 op1 = c_common_truthvalue_conversion (op1); 7934 converted = 1; 7935 } 7936 break; 7937 7938 /* Shift operations: result has same type as first operand; 7939 always convert second operand to int. 7940 Also set SHORT_SHIFT if shifting rightward. */ 7941 7942 case RSHIFT_EXPR: 7943 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE) 7944 { 7945 if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0) 7946 { 7947 if (tree_int_cst_sgn (op1) < 0) 7948 warning (0, "right shift count is negative"); 7949 else 7950 { 7951 if (!integer_zerop (op1)) 7952 short_shift = 1; 7953 7954 if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0) 7955 warning (0, "right shift count >= width of type"); 7956 } 7957 } 7958 7959 /* Use the type of the value to be shifted. */ 7960 result_type = type0; 7961 /* Convert the shift-count to an integer, regardless of size 7962 of value being shifted. */ 7963 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node) 7964 op1 = convert (integer_type_node, op1); 7965 /* Avoid converting op1 to result_type later. */ 7966 converted = 1; 7967 } 7968 break; 7969 7970 case LSHIFT_EXPR: 7971 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE) 7972 { 7973 if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0) 7974 { 7975 if (tree_int_cst_sgn (op1) < 0) 7976 warning (0, "left shift count is negative"); 7977 7978 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0) 7979 warning (0, "left shift count >= width of type"); 7980 } 7981 7982 /* Use the type of the value to be shifted. */ 7983 result_type = type0; 7984 /* Convert the shift-count to an integer, regardless of size 7985 of value being shifted. */ 7986 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node) 7987 op1 = convert (integer_type_node, op1); 7988 /* Avoid converting op1 to result_type later. */ 7989 converted = 1; 7990 } 7991 break; 7992 7993 case EQ_EXPR: 7994 case NE_EXPR: 7995 if (code0 == REAL_TYPE || code1 == REAL_TYPE) 7996 warning (OPT_Wfloat_equal, 7997 "comparing floating point with == or != is unsafe"); 7998 /* Result of comparison is always int, 7999 but don't convert the args to int! */ 8000 build_type = integer_type_node; 8001 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE 8002 || code0 == COMPLEX_TYPE) 8003 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE 8004 || code1 == COMPLEX_TYPE)) 8005 short_compare = 1; 8006 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE) 8007 { 8008 tree tt0 = TREE_TYPE (type0); 8009 tree tt1 = TREE_TYPE (type1); 8010 /* Anything compares with void *. void * compares with anything. 8011 Otherwise, the targets must be compatible 8012 and both must be object or both incomplete. */ 8013 if (comp_target_types (type0, type1)) 8014 result_type = common_pointer_type (type0, type1); 8015 else if (VOID_TYPE_P (tt0)) 8016 { 8017 /* op0 != orig_op0 detects the case of something 8018 whose value is 0 but which isn't a valid null ptr const. */ 8019 if (pedantic && !null_pointer_constant_p (orig_op0) 8020 && TREE_CODE (tt1) == FUNCTION_TYPE) 8021 pedwarn ("ISO C forbids comparison of %<void *%>" 8022 " with function pointer"); 8023 } 8024 else if (VOID_TYPE_P (tt1)) 8025 { 8026 if (pedantic && !null_pointer_constant_p (orig_op1) 8027 && TREE_CODE (tt0) == FUNCTION_TYPE) 8028 pedwarn ("ISO C forbids comparison of %<void *%>" 8029 " with function pointer"); 8030 } 8031 else 8032 /* Avoid warning about the volatile ObjC EH puts on decls. */ 8033 if (!objc_ok) 8034 pedwarn ("comparison of distinct pointer types lacks a cast"); 8035 8036 if (result_type == NULL_TREE) 8037 result_type = ptr_type_node; 8038 } 8039 else if (code0 == POINTER_TYPE && null_pointer_constant_p (orig_op1)) 8040 { 8041 if (TREE_CODE (op0) == ADDR_EXPR 8042 && DECL_P (TREE_OPERAND (op0, 0)) 8043 && (TREE_CODE (TREE_OPERAND (op0, 0)) == PARM_DECL 8044 || TREE_CODE (TREE_OPERAND (op0, 0)) == LABEL_DECL 8045 || !DECL_WEAK (TREE_OPERAND (op0, 0)))) 8046 warning (OPT_Waddress, "the address of %qD will never be NULL", 8047 TREE_OPERAND (op0, 0)); 8048 result_type = type0; 8049 } 8050 else if (code1 == POINTER_TYPE && null_pointer_constant_p (orig_op0)) 8051 { 8052 if (TREE_CODE (op1) == ADDR_EXPR 8053 && DECL_P (TREE_OPERAND (op1, 0)) 8054 && (TREE_CODE (TREE_OPERAND (op1, 0)) == PARM_DECL 8055 || TREE_CODE (TREE_OPERAND (op1, 0)) == LABEL_DECL 8056 || !DECL_WEAK (TREE_OPERAND (op1, 0)))) 8057 warning (OPT_Waddress, "the address of %qD will never be NULL", 8058 TREE_OPERAND (op1, 0)); 8059 result_type = type1; 8060 } 8061 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE) 8062 { 8063 result_type = type0; 8064 pedwarn ("comparison between pointer and integer"); 8065 } 8066 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE) 8067 { 8068 result_type = type1; 8069 pedwarn ("comparison between pointer and integer"); 8070 } 8071 break; 8072 8073 case LE_EXPR: 8074 case GE_EXPR: 8075 case LT_EXPR: 8076 case GT_EXPR: 8077 build_type = integer_type_node; 8078 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE) 8079 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE)) 8080 short_compare = 1; 8081 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE) 8082 { 8083 if (comp_target_types (type0, type1)) 8084 { 8085 result_type = common_pointer_type (type0, type1); 8086 if (!COMPLETE_TYPE_P (TREE_TYPE (type0)) 8087 != !COMPLETE_TYPE_P (TREE_TYPE (type1))) 8088 pedwarn ("comparison of complete and incomplete pointers"); 8089 else if (pedantic 8090 && TREE_CODE (TREE_TYPE (type0)) == FUNCTION_TYPE) 8091 pedwarn ("ISO C forbids ordered comparisons of pointers to functions"); 8092 } 8093 else 8094 { 8095 result_type = ptr_type_node; 8096 pedwarn ("comparison of distinct pointer types lacks a cast"); 8097 } 8098 } 8099 else if (code0 == POINTER_TYPE && null_pointer_constant_p (orig_op1)) 8100 { 8101 result_type = type0; 8102 if (pedantic || extra_warnings) 8103 pedwarn ("ordered comparison of pointer with integer zero"); 8104 } 8105 else if (code1 == POINTER_TYPE && null_pointer_constant_p (orig_op0)) 8106 { 8107 result_type = type1; 8108 if (pedantic) 8109 pedwarn ("ordered comparison of pointer with integer zero"); 8110 } 8111 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE) 8112 { 8113 result_type = type0; 8114 pedwarn ("comparison between pointer and integer"); 8115 } 8116 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE) 8117 { 8118 result_type = type1; 8119 pedwarn ("comparison between pointer and integer"); 8120 } 8121 break; 8122 8123 default: 8124 gcc_unreachable (); 8125 } 8126 8127 if (code0 == ERROR_MARK || code1 == ERROR_MARK) 8128 return error_mark_node; 8129 8130 if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE 8131 && (!tree_int_cst_equal (TYPE_SIZE (type0), TYPE_SIZE (type1)) 8132 || !same_scalar_type_ignoring_signedness (TREE_TYPE (type0), 8133 TREE_TYPE (type1)))) 8134 { 8135 binary_op_error (code); 8136 return error_mark_node; 8137 } 8138 8139 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE 8140 || code0 == VECTOR_TYPE) 8141 && 8142 (code1 == INTEGER_TYPE || code1 == REAL_TYPE || code1 == COMPLEX_TYPE 8143 || code1 == VECTOR_TYPE)) 8144 { 8145 int none_complex = (code0 != COMPLEX_TYPE && code1 != COMPLEX_TYPE); 8146 8147 if (shorten || common || short_compare) 8148 result_type = c_common_type (type0, type1); 8149 8150 /* For certain operations (which identify themselves by shorten != 0) 8151 if both args were extended from the same smaller type, 8152 do the arithmetic in that type and then extend. 8153 8154 shorten !=0 and !=1 indicates a bitwise operation. 8155 For them, this optimization is safe only if 8156 both args are zero-extended or both are sign-extended. 8157 Otherwise, we might change the result. 8158 Eg, (short)-1 | (unsigned short)-1 is (int)-1 8159 but calculated in (unsigned short) it would be (unsigned short)-1. */ 8160 8161 if (shorten && none_complex) 8162 { 8163 int unsigned0, unsigned1; 8164 tree arg0, arg1; 8165 int uns; 8166 tree type; 8167 8168 /* Cast OP0 and OP1 to RESULT_TYPE. Doing so prevents 8169 excessive narrowing when we call get_narrower below. For 8170 example, suppose that OP0 is of unsigned int extended 8171 from signed char and that RESULT_TYPE is long long int. 8172 If we explicitly cast OP0 to RESULT_TYPE, OP0 would look 8173 like 8174 8175 (long long int) (unsigned int) signed_char 8176 8177 which get_narrower would narrow down to 8178 8179 (unsigned int) signed char 8180 8181 If we do not cast OP0 first, get_narrower would return 8182 signed_char, which is inconsistent with the case of the 8183 explicit cast. */ 8184 op0 = convert (result_type, op0); 8185 op1 = convert (result_type, op1); 8186 8187 arg0 = get_narrower (op0, &unsigned0); 8188 arg1 = get_narrower (op1, &unsigned1); 8189 8190 /* UNS is 1 if the operation to be done is an unsigned one. */ 8191 uns = TYPE_UNSIGNED (result_type); 8192 8193 final_type = result_type; 8194 8195 /* Handle the case that OP0 (or OP1) does not *contain* a conversion 8196 but it *requires* conversion to FINAL_TYPE. */ 8197 8198 if ((TYPE_PRECISION (TREE_TYPE (op0)) 8199 == TYPE_PRECISION (TREE_TYPE (arg0))) 8200 && TREE_TYPE (op0) != final_type) 8201 unsigned0 = TYPE_UNSIGNED (TREE_TYPE (op0)); 8202 if ((TYPE_PRECISION (TREE_TYPE (op1)) 8203 == TYPE_PRECISION (TREE_TYPE (arg1))) 8204 && TREE_TYPE (op1) != final_type) 8205 unsigned1 = TYPE_UNSIGNED (TREE_TYPE (op1)); 8206 8207 /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */ 8208 8209 /* For bitwise operations, signedness of nominal type 8210 does not matter. Consider only how operands were extended. */ 8211 if (shorten == -1) 8212 uns = unsigned0; 8213 8214 /* Note that in all three cases below we refrain from optimizing 8215 an unsigned operation on sign-extended args. 8216 That would not be valid. */ 8217 8218 /* Both args variable: if both extended in same way 8219 from same width, do it in that width. 8220 Do it unsigned if args were zero-extended. */ 8221 if ((TYPE_PRECISION (TREE_TYPE (arg0)) 8222 < TYPE_PRECISION (result_type)) 8223 && (TYPE_PRECISION (TREE_TYPE (arg1)) 8224 == TYPE_PRECISION (TREE_TYPE (arg0))) 8225 && unsigned0 == unsigned1 8226 && (unsigned0 || !uns)) 8227 result_type 8228 = c_common_signed_or_unsigned_type 8229 (unsigned0, common_type (TREE_TYPE (arg0), TREE_TYPE (arg1))); 8230 else if (TREE_CODE (arg0) == INTEGER_CST 8231 && (unsigned1 || !uns) 8232 && (TYPE_PRECISION (TREE_TYPE (arg1)) 8233 < TYPE_PRECISION (result_type)) 8234 && (type 8235 = c_common_signed_or_unsigned_type (unsigned1, 8236 TREE_TYPE (arg1)), 8237 int_fits_type_p (arg0, type))) 8238 result_type = type; 8239 else if (TREE_CODE (arg1) == INTEGER_CST 8240 && (unsigned0 || !uns) 8241 && (TYPE_PRECISION (TREE_TYPE (arg0)) 8242 < TYPE_PRECISION (result_type)) 8243 && (type 8244 = c_common_signed_or_unsigned_type (unsigned0, 8245 TREE_TYPE (arg0)), 8246 int_fits_type_p (arg1, type))) 8247 result_type = type; 8248 } 8249 8250 /* Shifts can be shortened if shifting right. */ 8251 8252 if (short_shift) 8253 { 8254 int unsigned_arg; 8255 tree arg0 = get_narrower (op0, &unsigned_arg); 8256 8257 final_type = result_type; 8258 8259 if (arg0 == op0 && final_type == TREE_TYPE (op0)) 8260 unsigned_arg = TYPE_UNSIGNED (TREE_TYPE (op0)); 8261 8262 if (TYPE_PRECISION (TREE_TYPE (arg0)) < TYPE_PRECISION (result_type) 8263 /* We can shorten only if the shift count is less than the 8264 number of bits in the smaller type size. */ 8265 && compare_tree_int (op1, TYPE_PRECISION (TREE_TYPE (arg0))) < 0 8266 /* We cannot drop an unsigned shift after sign-extension. */ 8267 && (!TYPE_UNSIGNED (final_type) || unsigned_arg)) 8268 { 8269 /* Do an unsigned shift if the operand was zero-extended. */ 8270 result_type 8271 = c_common_signed_or_unsigned_type (unsigned_arg, 8272 TREE_TYPE (arg0)); 8273 /* Convert value-to-be-shifted to that type. */ 8274 if (TREE_TYPE (op0) != result_type) 8275 op0 = convert (result_type, op0); 8276 converted = 1; 8277 } 8278 } 8279 8280 /* Comparison operations are shortened too but differently. 8281 They identify themselves by setting short_compare = 1. */ 8282 8283 if (short_compare) 8284 { 8285 /* Don't write &op0, etc., because that would prevent op0 8286 from being kept in a register. 8287 Instead, make copies of the our local variables and 8288 pass the copies by reference, then copy them back afterward. */ 8289 tree xop0 = op0, xop1 = op1, xresult_type = result_type; 8290 enum tree_code xresultcode = resultcode; 8291 tree val 8292 = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode); 8293 8294 if (val != 0) 8295 return val; 8296 8297 op0 = xop0, op1 = xop1; 8298 converted = 1; 8299 resultcode = xresultcode; 8300 8301 if (warn_sign_compare && skip_evaluation == 0) 8302 { 8303 int op0_signed = !TYPE_UNSIGNED (TREE_TYPE (orig_op0)); 8304 int op1_signed = !TYPE_UNSIGNED (TREE_TYPE (orig_op1)); 8305 int unsignedp0, unsignedp1; 8306 tree primop0 = get_narrower (op0, &unsignedp0); 8307 tree primop1 = get_narrower (op1, &unsignedp1); 8308 8309 xop0 = orig_op0; 8310 xop1 = orig_op1; 8311 STRIP_TYPE_NOPS (xop0); 8312 STRIP_TYPE_NOPS (xop1); 8313 8314 /* Give warnings for comparisons between signed and unsigned 8315 quantities that may fail. 8316 8317 Do the checking based on the original operand trees, so that 8318 casts will be considered, but default promotions won't be. 8319 8320 Do not warn if the comparison is being done in a signed type, 8321 since the signed type will only be chosen if it can represent 8322 all the values of the unsigned type. */ 8323 if (!TYPE_UNSIGNED (result_type)) 8324 /* OK */; 8325 /* Do not warn if both operands are the same signedness. */ 8326 else if (op0_signed == op1_signed) 8327 /* OK */; 8328 else 8329 { 8330 tree sop, uop; 8331 bool ovf; 8332 8333 if (op0_signed) 8334 sop = xop0, uop = xop1; 8335 else 8336 sop = xop1, uop = xop0; 8337 8338 /* Do not warn if the signed quantity is an 8339 unsuffixed integer literal (or some static 8340 constant expression involving such literals or a 8341 conditional expression involving such literals) 8342 and it is non-negative. */ 8343 if (tree_expr_nonnegative_warnv_p (sop, &ovf)) 8344 /* OK */; 8345 /* Do not warn if the comparison is an equality operation, 8346 the unsigned quantity is an integral constant, and it 8347 would fit in the result if the result were signed. */ 8348 else if (TREE_CODE (uop) == INTEGER_CST 8349 && (resultcode == EQ_EXPR || resultcode == NE_EXPR) 8350 && int_fits_type_p 8351 (uop, c_common_signed_type (result_type))) 8352 /* OK */; 8353 /* Do not warn if the unsigned quantity is an enumeration 8354 constant and its maximum value would fit in the result 8355 if the result were signed. */ 8356 else if (TREE_CODE (uop) == INTEGER_CST 8357 && TREE_CODE (TREE_TYPE (uop)) == ENUMERAL_TYPE 8358 && int_fits_type_p 8359 (TYPE_MAX_VALUE (TREE_TYPE (uop)), 8360 c_common_signed_type (result_type))) 8361 /* OK */; 8362 else 8363 warning (0, "comparison between signed and unsigned"); 8364 } 8365 8366 /* Warn if two unsigned values are being compared in a size 8367 larger than their original size, and one (and only one) is the 8368 result of a `~' operator. This comparison will always fail. 8369 8370 Also warn if one operand is a constant, and the constant 8371 does not have all bits set that are set in the ~ operand 8372 when it is extended. */ 8373 8374 if ((TREE_CODE (primop0) == BIT_NOT_EXPR) 8375 != (TREE_CODE (primop1) == BIT_NOT_EXPR)) 8376 { 8377 if (TREE_CODE (primop0) == BIT_NOT_EXPR) 8378 primop0 = get_narrower (TREE_OPERAND (primop0, 0), 8379 &unsignedp0); 8380 else 8381 primop1 = get_narrower (TREE_OPERAND (primop1, 0), 8382 &unsignedp1); 8383 8384 if (host_integerp (primop0, 0) || host_integerp (primop1, 0)) 8385 { 8386 tree primop; 8387 HOST_WIDE_INT constant, mask; 8388 int unsignedp, bits; 8389 8390 if (host_integerp (primop0, 0)) 8391 { 8392 primop = primop1; 8393 unsignedp = unsignedp1; 8394 constant = tree_low_cst (primop0, 0); 8395 } 8396 else 8397 { 8398 primop = primop0; 8399 unsignedp = unsignedp0; 8400 constant = tree_low_cst (primop1, 0); 8401 } 8402 8403 bits = TYPE_PRECISION (TREE_TYPE (primop)); 8404 if (bits < TYPE_PRECISION (result_type) 8405 && bits < HOST_BITS_PER_WIDE_INT && unsignedp) 8406 { 8407 mask = (~(HOST_WIDE_INT) 0) << bits; 8408 if ((mask & constant) != mask) 8409 warning (0, "comparison of promoted ~unsigned with constant"); 8410 } 8411 } 8412 else if (unsignedp0 && unsignedp1 8413 && (TYPE_PRECISION (TREE_TYPE (primop0)) 8414 < TYPE_PRECISION (result_type)) 8415 && (TYPE_PRECISION (TREE_TYPE (primop1)) 8416 < TYPE_PRECISION (result_type))) 8417 warning (0, "comparison of promoted ~unsigned with unsigned"); 8418 } 8419 } 8420 } 8421 } 8422 8423 /* At this point, RESULT_TYPE must be nonzero to avoid an error message. 8424 If CONVERTED is zero, both args will be converted to type RESULT_TYPE. 8425 Then the expression will be built. 8426 It will be given type FINAL_TYPE if that is nonzero; 8427 otherwise, it will be given type RESULT_TYPE. */ 8428 8429 if (!result_type) 8430 { 8431 binary_op_error (code); 8432 return error_mark_node; 8433 } 8434 8435 if (!converted) 8436 { 8437 if (TREE_TYPE (op0) != result_type) 8438 op0 = convert_and_check (result_type, op0); 8439 if (TREE_TYPE (op1) != result_type) 8440 op1 = convert_and_check (result_type, op1); 8441 8442 /* This can happen if one operand has a vector type, and the other 8443 has a different type. */ 8444 if (TREE_CODE (op0) == ERROR_MARK || TREE_CODE (op1) == ERROR_MARK) 8445 return error_mark_node; 8446 } 8447 8448 if (build_type == NULL_TREE) 8449 build_type = result_type; 8450 8451 { 8452 /* Treat expressions in initializers specially as they can't trap. */ 8453 tree result = require_constant_value ? fold_build2_initializer (resultcode, 8454 build_type, 8455 op0, op1) 8456 : fold_build2 (resultcode, build_type, 8457 op0, op1); 8458 8459 if (final_type != 0) 8460 result = convert (final_type, result); 8461 return result; 8462 } 8463} 8464 8465 8466/* Convert EXPR to be a truth-value, validating its type for this 8467 purpose. */ 8468 8469tree 8470c_objc_common_truthvalue_conversion (tree expr) 8471{ 8472 switch (TREE_CODE (TREE_TYPE (expr))) 8473 { 8474 case ARRAY_TYPE: 8475 error ("used array that cannot be converted to pointer where scalar is required"); 8476 return error_mark_node; 8477 8478 case RECORD_TYPE: 8479 error ("used struct type value where scalar is required"); 8480 return error_mark_node; 8481 8482 case UNION_TYPE: 8483 error ("used union type value where scalar is required"); 8484 return error_mark_node; 8485 8486 case FUNCTION_TYPE: 8487 gcc_unreachable (); 8488 8489 default: 8490 break; 8491 } 8492 8493 /* ??? Should we also give an error for void and vectors rather than 8494 leaving those to give errors later? */ 8495 return c_common_truthvalue_conversion (expr); 8496} 8497 8498 8499/* Convert EXPR to a contained DECL, updating *TC, *TI and *SE as 8500 required. */ 8501 8502tree 8503c_expr_to_decl (tree expr, bool *tc ATTRIBUTE_UNUSED, 8504 bool *ti ATTRIBUTE_UNUSED, bool *se) 8505{ 8506 if (TREE_CODE (expr) == COMPOUND_LITERAL_EXPR) 8507 { 8508 tree decl = COMPOUND_LITERAL_EXPR_DECL (expr); 8509 /* Executing a compound literal inside a function reinitializes 8510 it. */ 8511 if (!TREE_STATIC (decl)) 8512 *se = true; 8513 return decl; 8514 } 8515 else 8516 return expr; 8517} 8518 8519/* Like c_begin_compound_stmt, except force the retention of the BLOCK. */ 8520 8521tree 8522c_begin_omp_parallel (void) 8523{ 8524 tree block; 8525 8526 keep_next_level (); 8527 block = c_begin_compound_stmt (true); 8528 8529 return block; 8530} 8531 8532tree 8533c_finish_omp_parallel (tree clauses, tree block) 8534{ 8535 tree stmt; 8536 8537 block = c_end_compound_stmt (block, true); 8538 8539 stmt = make_node (OMP_PARALLEL); 8540 TREE_TYPE (stmt) = void_type_node; 8541 OMP_PARALLEL_CLAUSES (stmt) = clauses; 8542 OMP_PARALLEL_BODY (stmt) = block; 8543 8544 return add_stmt (stmt); 8545} 8546 8547/* For all elements of CLAUSES, validate them vs OpenMP constraints. 8548 Remove any elements from the list that are invalid. */ 8549 8550tree 8551c_finish_omp_clauses (tree clauses) 8552{ 8553 bitmap_head generic_head, firstprivate_head, lastprivate_head; 8554 tree c, t, *pc = &clauses; 8555 const char *name; 8556 8557 bitmap_obstack_initialize (NULL); 8558 bitmap_initialize (&generic_head, &bitmap_default_obstack); 8559 bitmap_initialize (&firstprivate_head, &bitmap_default_obstack); 8560 bitmap_initialize (&lastprivate_head, &bitmap_default_obstack); 8561 8562 for (pc = &clauses, c = clauses; c ; c = *pc) 8563 { 8564 bool remove = false; 8565 bool need_complete = false; 8566 bool need_implicitly_determined = false; 8567 8568 switch (OMP_CLAUSE_CODE (c)) 8569 { 8570 case OMP_CLAUSE_SHARED: 8571 name = "shared"; 8572 need_implicitly_determined = true; 8573 goto check_dup_generic; 8574 8575 case OMP_CLAUSE_PRIVATE: 8576 name = "private"; 8577 need_complete = true; 8578 need_implicitly_determined = true; 8579 goto check_dup_generic; 8580 8581 case OMP_CLAUSE_REDUCTION: 8582 name = "reduction"; 8583 need_implicitly_determined = true; 8584 t = OMP_CLAUSE_DECL (c); 8585 if (AGGREGATE_TYPE_P (TREE_TYPE (t)) 8586 || POINTER_TYPE_P (TREE_TYPE (t))) 8587 { 8588 error ("%qE has invalid type for %<reduction%>", t); 8589 remove = true; 8590 } 8591 else if (FLOAT_TYPE_P (TREE_TYPE (t))) 8592 { 8593 enum tree_code r_code = OMP_CLAUSE_REDUCTION_CODE (c); 8594 const char *r_name = NULL; 8595 8596 switch (r_code) 8597 { 8598 case PLUS_EXPR: 8599 case MULT_EXPR: 8600 case MINUS_EXPR: 8601 break; 8602 case BIT_AND_EXPR: 8603 r_name = "&"; 8604 break; 8605 case BIT_XOR_EXPR: 8606 r_name = "^"; 8607 break; 8608 case BIT_IOR_EXPR: 8609 r_name = "|"; 8610 break; 8611 case TRUTH_ANDIF_EXPR: 8612 r_name = "&&"; 8613 break; 8614 case TRUTH_ORIF_EXPR: 8615 r_name = "||"; 8616 break; 8617 default: 8618 gcc_unreachable (); 8619 } 8620 if (r_name) 8621 { 8622 error ("%qE has invalid type for %<reduction(%s)%>", 8623 t, r_name); 8624 remove = true; 8625 } 8626 } 8627 goto check_dup_generic; 8628 8629 case OMP_CLAUSE_COPYPRIVATE: 8630 name = "copyprivate"; 8631 goto check_dup_generic; 8632 8633 case OMP_CLAUSE_COPYIN: 8634 name = "copyin"; 8635 t = OMP_CLAUSE_DECL (c); 8636 if (TREE_CODE (t) != VAR_DECL || !DECL_THREAD_LOCAL_P (t)) 8637 { 8638 error ("%qE must be %<threadprivate%> for %<copyin%>", t); 8639 remove = true; 8640 } 8641 goto check_dup_generic; 8642 8643 check_dup_generic: 8644 t = OMP_CLAUSE_DECL (c); 8645 if (TREE_CODE (t) != VAR_DECL && TREE_CODE (t) != PARM_DECL) 8646 { 8647 error ("%qE is not a variable in clause %qs", t, name); 8648 remove = true; 8649 } 8650 else if (bitmap_bit_p (&generic_head, DECL_UID (t)) 8651 || bitmap_bit_p (&firstprivate_head, DECL_UID (t)) 8652 || bitmap_bit_p (&lastprivate_head, DECL_UID (t))) 8653 { 8654 error ("%qE appears more than once in data clauses", t); 8655 remove = true; 8656 } 8657 else 8658 bitmap_set_bit (&generic_head, DECL_UID (t)); 8659 break; 8660 8661 case OMP_CLAUSE_FIRSTPRIVATE: 8662 name = "firstprivate"; 8663 t = OMP_CLAUSE_DECL (c); 8664 need_complete = true; 8665 need_implicitly_determined = true; 8666 if (TREE_CODE (t) != VAR_DECL && TREE_CODE (t) != PARM_DECL) 8667 { 8668 error ("%qE is not a variable in clause %<firstprivate%>", t); 8669 remove = true; 8670 } 8671 else if (bitmap_bit_p (&generic_head, DECL_UID (t)) 8672 || bitmap_bit_p (&firstprivate_head, DECL_UID (t))) 8673 { 8674 error ("%qE appears more than once in data clauses", t); 8675 remove = true; 8676 } 8677 else 8678 bitmap_set_bit (&firstprivate_head, DECL_UID (t)); 8679 break; 8680 8681 case OMP_CLAUSE_LASTPRIVATE: 8682 name = "lastprivate"; 8683 t = OMP_CLAUSE_DECL (c); 8684 need_complete = true; 8685 need_implicitly_determined = true; 8686 if (TREE_CODE (t) != VAR_DECL && TREE_CODE (t) != PARM_DECL) 8687 { 8688 error ("%qE is not a variable in clause %<lastprivate%>", t); 8689 remove = true; 8690 } 8691 else if (bitmap_bit_p (&generic_head, DECL_UID (t)) 8692 || bitmap_bit_p (&lastprivate_head, DECL_UID (t))) 8693 { 8694 error ("%qE appears more than once in data clauses", t); 8695 remove = true; 8696 } 8697 else 8698 bitmap_set_bit (&lastprivate_head, DECL_UID (t)); 8699 break; 8700 8701 case OMP_CLAUSE_IF: 8702 case OMP_CLAUSE_NUM_THREADS: 8703 case OMP_CLAUSE_SCHEDULE: 8704 case OMP_CLAUSE_NOWAIT: 8705 case OMP_CLAUSE_ORDERED: 8706 case OMP_CLAUSE_DEFAULT: 8707 pc = &OMP_CLAUSE_CHAIN (c); 8708 continue; 8709 8710 default: 8711 gcc_unreachable (); 8712 } 8713 8714 if (!remove) 8715 { 8716 t = OMP_CLAUSE_DECL (c); 8717 8718 if (need_complete) 8719 { 8720 t = require_complete_type (t); 8721 if (t == error_mark_node) 8722 remove = true; 8723 } 8724 8725 if (need_implicitly_determined) 8726 { 8727 const char *share_name = NULL; 8728 8729 if (TREE_CODE (t) == VAR_DECL && DECL_THREAD_LOCAL_P (t)) 8730 share_name = "threadprivate"; 8731 else switch (c_omp_predetermined_sharing (t)) 8732 { 8733 case OMP_CLAUSE_DEFAULT_UNSPECIFIED: 8734 break; 8735 case OMP_CLAUSE_DEFAULT_SHARED: 8736 share_name = "shared"; 8737 break; 8738 case OMP_CLAUSE_DEFAULT_PRIVATE: 8739 share_name = "private"; 8740 break; 8741 default: 8742 gcc_unreachable (); 8743 } 8744 if (share_name) 8745 { 8746 error ("%qE is predetermined %qs for %qs", 8747 t, share_name, name); 8748 remove = true; 8749 } 8750 } 8751 } 8752 8753 if (remove) 8754 *pc = OMP_CLAUSE_CHAIN (c); 8755 else 8756 pc = &OMP_CLAUSE_CHAIN (c); 8757 } 8758 8759 bitmap_obstack_release (NULL); 8760 return clauses; 8761} 8762