c-typeck.c revision 258081
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) == ADDR_EXPR 1880 && (TREE_TYPE (TREE_OPERAND (pointer, 0)) 1881 == TREE_TYPE (type))) 1882 return TREE_OPERAND (pointer, 0); 1883 else 1884 { 1885 tree t = TREE_TYPE (type); 1886 tree ref; 1887 1888 ref = build1 (INDIRECT_REF, t, pointer); 1889 1890 if (!COMPLETE_OR_VOID_TYPE_P (t) && TREE_CODE (t) != ARRAY_TYPE) 1891 { 1892 error ("dereferencing pointer to incomplete type"); 1893 return error_mark_node; 1894 } 1895 if (VOID_TYPE_P (t) && skip_evaluation == 0) 1896 warning (0, "dereferencing %<void *%> pointer"); 1897 1898 /* We *must* set TREE_READONLY when dereferencing a pointer to const, 1899 so that we get the proper error message if the result is used 1900 to assign to. Also, &* is supposed to be a no-op. 1901 And ANSI C seems to specify that the type of the result 1902 should be the const type. */ 1903 /* A de-reference of a pointer to const is not a const. It is valid 1904 to change it via some other pointer. */ 1905 TREE_READONLY (ref) = TYPE_READONLY (t); 1906 TREE_SIDE_EFFECTS (ref) 1907 = TYPE_VOLATILE (t) || TREE_SIDE_EFFECTS (pointer); 1908 TREE_THIS_VOLATILE (ref) = TYPE_VOLATILE (t); 1909 return ref; 1910 } 1911 } 1912 else if (TREE_CODE (pointer) != ERROR_MARK) 1913 error ("invalid type argument of %qs", errorstring); 1914 return error_mark_node; 1915} 1916 1917/* This handles expressions of the form "a[i]", which denotes 1918 an array reference. 1919 1920 This is logically equivalent in C to *(a+i), but we may do it differently. 1921 If A is a variable or a member, we generate a primitive ARRAY_REF. 1922 This avoids forcing the array out of registers, and can work on 1923 arrays that are not lvalues (for example, members of structures returned 1924 by functions). */ 1925 1926tree 1927build_array_ref (tree array, tree index) 1928{ 1929 bool swapped = false; 1930 if (TREE_TYPE (array) == error_mark_node 1931 || TREE_TYPE (index) == error_mark_node) 1932 return error_mark_node; 1933 1934 if (TREE_CODE (TREE_TYPE (array)) != ARRAY_TYPE 1935 && TREE_CODE (TREE_TYPE (array)) != POINTER_TYPE) 1936 { 1937 tree temp; 1938 if (TREE_CODE (TREE_TYPE (index)) != ARRAY_TYPE 1939 && TREE_CODE (TREE_TYPE (index)) != POINTER_TYPE) 1940 { 1941 error ("subscripted value is neither array nor pointer"); 1942 return error_mark_node; 1943 } 1944 temp = array; 1945 array = index; 1946 index = temp; 1947 swapped = true; 1948 } 1949 1950 if (!INTEGRAL_TYPE_P (TREE_TYPE (index))) 1951 { 1952 error ("array subscript is not an integer"); 1953 return error_mark_node; 1954 } 1955 1956 if (TREE_CODE (TREE_TYPE (TREE_TYPE (array))) == FUNCTION_TYPE) 1957 { 1958 error ("subscripted value is pointer to function"); 1959 return error_mark_node; 1960 } 1961 1962 /* ??? Existing practice has been to warn only when the char 1963 index is syntactically the index, not for char[array]. */ 1964 if (!swapped) 1965 warn_array_subscript_with_type_char (index); 1966 1967 /* Apply default promotions *after* noticing character types. */ 1968 index = default_conversion (index); 1969 1970 gcc_assert (TREE_CODE (TREE_TYPE (index)) == INTEGER_TYPE); 1971 1972 if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE) 1973 { 1974 tree rval, type; 1975 1976 /* An array that is indexed by a non-constant 1977 cannot be stored in a register; we must be able to do 1978 address arithmetic on its address. 1979 Likewise an array of elements of variable size. */ 1980 if (TREE_CODE (index) != INTEGER_CST 1981 || (COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (array))) 1982 && TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array)))) != INTEGER_CST)) 1983 { 1984 if (!c_mark_addressable (array)) 1985 return error_mark_node; 1986 } 1987 /* An array that is indexed by a constant value which is not within 1988 the array bounds cannot be stored in a register either; because we 1989 would get a crash in store_bit_field/extract_bit_field when trying 1990 to access a non-existent part of the register. */ 1991 if (TREE_CODE (index) == INTEGER_CST 1992 && TYPE_DOMAIN (TREE_TYPE (array)) 1993 && !int_fits_type_p (index, TYPE_DOMAIN (TREE_TYPE (array)))) 1994 { 1995 if (!c_mark_addressable (array)) 1996 return error_mark_node; 1997 } 1998 1999 if (pedantic) 2000 { 2001 tree foo = array; 2002 while (TREE_CODE (foo) == COMPONENT_REF) 2003 foo = TREE_OPERAND (foo, 0); 2004 if (TREE_CODE (foo) == VAR_DECL && C_DECL_REGISTER (foo)) 2005 pedwarn ("ISO C forbids subscripting %<register%> array"); 2006 else if (!flag_isoc99 && !lvalue_p (foo)) 2007 pedwarn ("ISO C90 forbids subscripting non-lvalue array"); 2008 } 2009 2010 type = TREE_TYPE (TREE_TYPE (array)); 2011 if (TREE_CODE (type) != ARRAY_TYPE) 2012 type = TYPE_MAIN_VARIANT (type); 2013 rval = build4 (ARRAY_REF, type, array, index, NULL_TREE, NULL_TREE); 2014 /* Array ref is const/volatile if the array elements are 2015 or if the array is. */ 2016 TREE_READONLY (rval) 2017 |= (TYPE_READONLY (TREE_TYPE (TREE_TYPE (array))) 2018 | TREE_READONLY (array)); 2019 TREE_SIDE_EFFECTS (rval) 2020 |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array))) 2021 | TREE_SIDE_EFFECTS (array)); 2022 TREE_THIS_VOLATILE (rval) 2023 |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array))) 2024 /* This was added by rms on 16 Nov 91. 2025 It fixes vol struct foo *a; a->elts[1] 2026 in an inline function. 2027 Hope it doesn't break something else. */ 2028 | TREE_THIS_VOLATILE (array)); 2029 return require_complete_type (fold (rval)); 2030 } 2031 else 2032 { 2033 tree ar = default_conversion (array); 2034 2035 if (ar == error_mark_node) 2036 return ar; 2037 2038 gcc_assert (TREE_CODE (TREE_TYPE (ar)) == POINTER_TYPE); 2039 gcc_assert (TREE_CODE (TREE_TYPE (TREE_TYPE (ar))) != FUNCTION_TYPE); 2040 2041 return build_indirect_ref (build_binary_op (PLUS_EXPR, ar, index, 0), 2042 "array indexing"); 2043 } 2044} 2045 2046/* Build an external reference to identifier ID. FUN indicates 2047 whether this will be used for a function call. LOC is the source 2048 location of the identifier. */ 2049tree 2050build_external_ref (tree id, int fun, location_t loc) 2051{ 2052 tree ref; 2053 tree decl = lookup_name (id); 2054 2055 /* In Objective-C, an instance variable (ivar) may be preferred to 2056 whatever lookup_name() found. */ 2057 decl = objc_lookup_ivar (decl, id); 2058 2059 if (decl && decl != error_mark_node) 2060 ref = decl; 2061 else if (fun) 2062 /* Implicit function declaration. */ 2063 ref = implicitly_declare (id); 2064 else if (decl == error_mark_node) 2065 /* Don't complain about something that's already been 2066 complained about. */ 2067 return error_mark_node; 2068 else 2069 { 2070 undeclared_variable (id, loc); 2071 return error_mark_node; 2072 } 2073 2074 if (TREE_TYPE (ref) == error_mark_node) 2075 return error_mark_node; 2076 2077 if (TREE_DEPRECATED (ref)) 2078 warn_deprecated_use (ref); 2079 2080 if (!skip_evaluation) 2081 assemble_external (ref); 2082 TREE_USED (ref) = 1; 2083 2084 if (TREE_CODE (ref) == FUNCTION_DECL && !in_alignof) 2085 { 2086 if (!in_sizeof && !in_typeof) 2087 C_DECL_USED (ref) = 1; 2088 else if (DECL_INITIAL (ref) == 0 2089 && DECL_EXTERNAL (ref) 2090 && !TREE_PUBLIC (ref)) 2091 record_maybe_used_decl (ref); 2092 } 2093 2094 if (TREE_CODE (ref) == CONST_DECL) 2095 { 2096 used_types_insert (TREE_TYPE (ref)); 2097 ref = DECL_INITIAL (ref); 2098 TREE_CONSTANT (ref) = 1; 2099 TREE_INVARIANT (ref) = 1; 2100 } 2101 else if (current_function_decl != 0 2102 && !DECL_FILE_SCOPE_P (current_function_decl) 2103 && (TREE_CODE (ref) == VAR_DECL 2104 || TREE_CODE (ref) == PARM_DECL 2105 || TREE_CODE (ref) == FUNCTION_DECL)) 2106 { 2107 tree context = decl_function_context (ref); 2108 2109 if (context != 0 && context != current_function_decl) 2110 DECL_NONLOCAL (ref) = 1; 2111 } 2112 /* C99 6.7.4p3: An inline definition of a function with external 2113 linkage ... shall not contain a reference to an identifier with 2114 internal linkage. */ 2115 else if (current_function_decl != 0 2116 && DECL_DECLARED_INLINE_P (current_function_decl) 2117 && DECL_EXTERNAL (current_function_decl) 2118 && VAR_OR_FUNCTION_DECL_P (ref) 2119 && DECL_FILE_SCOPE_P (ref) 2120 && pedantic 2121 && (TREE_CODE (ref) != VAR_DECL || TREE_STATIC (ref)) 2122 && ! TREE_PUBLIC (ref)) 2123 pedwarn ("%H%qD is static but used in inline function %qD " 2124 "which is not static", &loc, ref, current_function_decl); 2125 2126 return ref; 2127} 2128 2129/* Record details of decls possibly used inside sizeof or typeof. */ 2130struct maybe_used_decl 2131{ 2132 /* The decl. */ 2133 tree decl; 2134 /* The level seen at (in_sizeof + in_typeof). */ 2135 int level; 2136 /* The next one at this level or above, or NULL. */ 2137 struct maybe_used_decl *next; 2138}; 2139 2140static struct maybe_used_decl *maybe_used_decls; 2141 2142/* Record that DECL, an undefined static function reference seen 2143 inside sizeof or typeof, might be used if the operand of sizeof is 2144 a VLA type or the operand of typeof is a variably modified 2145 type. */ 2146 2147static void 2148record_maybe_used_decl (tree decl) 2149{ 2150 struct maybe_used_decl *t = XOBNEW (&parser_obstack, struct maybe_used_decl); 2151 t->decl = decl; 2152 t->level = in_sizeof + in_typeof; 2153 t->next = maybe_used_decls; 2154 maybe_used_decls = t; 2155} 2156 2157/* Pop the stack of decls possibly used inside sizeof or typeof. If 2158 USED is false, just discard them. If it is true, mark them used 2159 (if no longer inside sizeof or typeof) or move them to the next 2160 level up (if still inside sizeof or typeof). */ 2161 2162void 2163pop_maybe_used (bool used) 2164{ 2165 struct maybe_used_decl *p = maybe_used_decls; 2166 int cur_level = in_sizeof + in_typeof; 2167 while (p && p->level > cur_level) 2168 { 2169 if (used) 2170 { 2171 if (cur_level == 0) 2172 C_DECL_USED (p->decl) = 1; 2173 else 2174 p->level = cur_level; 2175 } 2176 p = p->next; 2177 } 2178 if (!used || cur_level == 0) 2179 maybe_used_decls = p; 2180} 2181 2182/* Return the result of sizeof applied to EXPR. */ 2183 2184struct c_expr 2185c_expr_sizeof_expr (struct c_expr expr) 2186{ 2187 struct c_expr ret; 2188 if (expr.value == error_mark_node) 2189 { 2190 ret.value = error_mark_node; 2191 ret.original_code = ERROR_MARK; 2192 pop_maybe_used (false); 2193 } 2194 else 2195 { 2196 ret.value = c_sizeof (TREE_TYPE (expr.value)); 2197 ret.original_code = ERROR_MARK; 2198 if (c_vla_type_p (TREE_TYPE (expr.value))) 2199 { 2200 /* sizeof is evaluated when given a vla (C99 6.5.3.4p2). */ 2201 ret.value = build2 (COMPOUND_EXPR, TREE_TYPE (ret.value), expr.value, ret.value); 2202 } 2203 pop_maybe_used (C_TYPE_VARIABLE_SIZE (TREE_TYPE (expr.value))); 2204 } 2205 return ret; 2206} 2207 2208/* Return the result of sizeof applied to T, a structure for the type 2209 name passed to sizeof (rather than the type itself). */ 2210 2211struct c_expr 2212c_expr_sizeof_type (struct c_type_name *t) 2213{ 2214 tree type; 2215 struct c_expr ret; 2216 type = groktypename (t); 2217 ret.value = c_sizeof (type); 2218 ret.original_code = ERROR_MARK; 2219 pop_maybe_used (type != error_mark_node 2220 ? C_TYPE_VARIABLE_SIZE (type) : false); 2221 return ret; 2222} 2223 2224/* Build a function call to function FUNCTION with parameters PARAMS. 2225 PARAMS is a list--a chain of TREE_LIST nodes--in which the 2226 TREE_VALUE of each node is a parameter-expression. 2227 FUNCTION's data type may be a function type or a pointer-to-function. */ 2228 2229tree 2230build_function_call (tree function, tree params) 2231{ 2232 tree fntype, fundecl = 0; 2233 tree coerced_params; 2234 tree name = NULL_TREE, result; 2235 tree tem; 2236 2237 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */ 2238 STRIP_TYPE_NOPS (function); 2239 2240 /* Convert anything with function type to a pointer-to-function. */ 2241 if (TREE_CODE (function) == FUNCTION_DECL) 2242 { 2243 /* Implement type-directed function overloading for builtins. 2244 resolve_overloaded_builtin and targetm.resolve_overloaded_builtin 2245 handle all the type checking. The result is a complete expression 2246 that implements this function call. */ 2247 tem = resolve_overloaded_builtin (function, params); 2248 if (tem) 2249 return tem; 2250 2251 name = DECL_NAME (function); 2252 fundecl = function; 2253 } 2254 if (TREE_CODE (TREE_TYPE (function)) == FUNCTION_TYPE) 2255 function = function_to_pointer_conversion (function); 2256 2257 /* For Objective-C, convert any calls via a cast to OBJC_TYPE_REF 2258 expressions, like those used for ObjC messenger dispatches. */ 2259 function = objc_rewrite_function_call (function, params); 2260 2261 fntype = TREE_TYPE (function); 2262 2263 if (TREE_CODE (fntype) == ERROR_MARK) 2264 return error_mark_node; 2265 2266 if (!(TREE_CODE (fntype) == POINTER_TYPE 2267 && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE)) 2268 { 2269 error ("called object %qE is not a function", function); 2270 return error_mark_node; 2271 } 2272 2273 if (fundecl && TREE_THIS_VOLATILE (fundecl)) 2274 current_function_returns_abnormally = 1; 2275 2276 /* fntype now gets the type of function pointed to. */ 2277 fntype = TREE_TYPE (fntype); 2278 2279 /* Check that the function is called through a compatible prototype. 2280 If it is not, replace the call by a trap, wrapped up in a compound 2281 expression if necessary. This has the nice side-effect to prevent 2282 the tree-inliner from generating invalid assignment trees which may 2283 blow up in the RTL expander later. */ 2284 if ((TREE_CODE (function) == NOP_EXPR 2285 || TREE_CODE (function) == CONVERT_EXPR) 2286 && TREE_CODE (tem = TREE_OPERAND (function, 0)) == ADDR_EXPR 2287 && TREE_CODE (tem = TREE_OPERAND (tem, 0)) == FUNCTION_DECL 2288 && !comptypes (fntype, TREE_TYPE (tem))) 2289 { 2290 tree return_type = TREE_TYPE (fntype); 2291 tree trap = build_function_call (built_in_decls[BUILT_IN_TRAP], 2292 NULL_TREE); 2293 2294 /* This situation leads to run-time undefined behavior. We can't, 2295 therefore, simply error unless we can prove that all possible 2296 executions of the program must execute the code. */ 2297 warning (0, "function called through a non-compatible type"); 2298 2299 /* We can, however, treat "undefined" any way we please. 2300 Call abort to encourage the user to fix the program. */ 2301 inform ("if this code is reached, the program will abort"); 2302 2303 if (VOID_TYPE_P (return_type)) 2304 return trap; 2305 else 2306 { 2307 tree rhs; 2308 2309 if (AGGREGATE_TYPE_P (return_type)) 2310 rhs = build_compound_literal (return_type, 2311 build_constructor (return_type, 0)); 2312 else 2313 rhs = fold_convert (return_type, integer_zero_node); 2314 2315 return build2 (COMPOUND_EXPR, return_type, trap, rhs); 2316 } 2317 } 2318 2319 /* Convert the parameters to the types declared in the 2320 function prototype, or apply default promotions. */ 2321 2322 coerced_params 2323 = convert_arguments (TYPE_ARG_TYPES (fntype), params, function, fundecl); 2324 2325 if (coerced_params == error_mark_node) 2326 return error_mark_node; 2327 2328 /* Check that the arguments to the function are valid. */ 2329 2330 check_function_arguments (TYPE_ATTRIBUTES (fntype), coerced_params, 2331 TYPE_ARG_TYPES (fntype)); 2332 2333 if (require_constant_value) 2334 { 2335 result = fold_build3_initializer (CALL_EXPR, TREE_TYPE (fntype), 2336 function, coerced_params, NULL_TREE); 2337 2338 if (TREE_CONSTANT (result) 2339 && (name == NULL_TREE 2340 || strncmp (IDENTIFIER_POINTER (name), "__builtin_", 10) != 0)) 2341 pedwarn_init ("initializer element is not constant"); 2342 } 2343 else 2344 result = fold_build3 (CALL_EXPR, TREE_TYPE (fntype), 2345 function, coerced_params, NULL_TREE); 2346 2347 if (VOID_TYPE_P (TREE_TYPE (result))) 2348 return result; 2349 return require_complete_type (result); 2350} 2351 2352/* Convert the argument expressions in the list VALUES 2353 to the types in the list TYPELIST. The result is a list of converted 2354 argument expressions, unless there are too few arguments in which 2355 case it is error_mark_node. 2356 2357 If TYPELIST is exhausted, or when an element has NULL as its type, 2358 perform the default conversions. 2359 2360 PARMLIST is the chain of parm decls for the function being called. 2361 It may be 0, if that info is not available. 2362 It is used only for generating error messages. 2363 2364 FUNCTION is a tree for the called function. It is used only for 2365 error messages, where it is formatted with %qE. 2366 2367 This is also where warnings about wrong number of args are generated. 2368 2369 Both VALUES and the returned value are chains of TREE_LIST nodes 2370 with the elements of the list in the TREE_VALUE slots of those nodes. */ 2371 2372static tree 2373convert_arguments (tree typelist, tree values, tree function, tree fundecl) 2374{ 2375 tree typetail, valtail; 2376 tree result = NULL; 2377 int parmnum; 2378 tree selector; 2379 2380 /* Change pointer to function to the function itself for 2381 diagnostics. */ 2382 if (TREE_CODE (function) == ADDR_EXPR 2383 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL) 2384 function = TREE_OPERAND (function, 0); 2385 2386 /* Handle an ObjC selector specially for diagnostics. */ 2387 selector = objc_message_selector (); 2388 2389 /* Scan the given expressions and types, producing individual 2390 converted arguments and pushing them on RESULT in reverse order. */ 2391 2392 for (valtail = values, typetail = typelist, parmnum = 0; 2393 valtail; 2394 valtail = TREE_CHAIN (valtail), parmnum++) 2395 { 2396 tree type = typetail ? TREE_VALUE (typetail) : 0; 2397 tree val = TREE_VALUE (valtail); 2398 tree rname = function; 2399 int argnum = parmnum + 1; 2400 const char *invalid_func_diag; 2401 2402 if (type == void_type_node) 2403 { 2404 error ("too many arguments to function %qE", function); 2405 break; 2406 } 2407 2408 if (selector && argnum > 2) 2409 { 2410 rname = selector; 2411 argnum -= 2; 2412 } 2413 2414 STRIP_TYPE_NOPS (val); 2415 2416 val = require_complete_type (val); 2417 2418 if (type != 0) 2419 { 2420 /* Formal parm type is specified by a function prototype. */ 2421 tree parmval; 2422 2423 if (type == error_mark_node || !COMPLETE_TYPE_P (type)) 2424 { 2425 error ("type of formal parameter %d is incomplete", parmnum + 1); 2426 parmval = val; 2427 } 2428 else 2429 { 2430 /* Optionally warn about conversions that 2431 differ from the default conversions. */ 2432 if (warn_conversion || warn_traditional) 2433 { 2434 unsigned int formal_prec = TYPE_PRECISION (type); 2435 2436 if (INTEGRAL_TYPE_P (type) 2437 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE) 2438 warning (0, "passing argument %d of %qE as integer " 2439 "rather than floating due to prototype", 2440 argnum, rname); 2441 if (INTEGRAL_TYPE_P (type) 2442 && TREE_CODE (TREE_TYPE (val)) == COMPLEX_TYPE) 2443 warning (0, "passing argument %d of %qE as integer " 2444 "rather than complex due to prototype", 2445 argnum, rname); 2446 else if (TREE_CODE (type) == COMPLEX_TYPE 2447 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE) 2448 warning (0, "passing argument %d of %qE as complex " 2449 "rather than floating due to prototype", 2450 argnum, rname); 2451 else if (TREE_CODE (type) == REAL_TYPE 2452 && INTEGRAL_TYPE_P (TREE_TYPE (val))) 2453 warning (0, "passing argument %d of %qE as floating " 2454 "rather than integer due to prototype", 2455 argnum, rname); 2456 else if (TREE_CODE (type) == COMPLEX_TYPE 2457 && INTEGRAL_TYPE_P (TREE_TYPE (val))) 2458 warning (0, "passing argument %d of %qE as complex " 2459 "rather than integer due to prototype", 2460 argnum, rname); 2461 else if (TREE_CODE (type) == REAL_TYPE 2462 && TREE_CODE (TREE_TYPE (val)) == COMPLEX_TYPE) 2463 warning (0, "passing argument %d of %qE as floating " 2464 "rather than complex due to prototype", 2465 argnum, rname); 2466 /* ??? At some point, messages should be written about 2467 conversions between complex types, but that's too messy 2468 to do now. */ 2469 else if (TREE_CODE (type) == REAL_TYPE 2470 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE) 2471 { 2472 /* Warn if any argument is passed as `float', 2473 since without a prototype it would be `double'. */ 2474 if (formal_prec == TYPE_PRECISION (float_type_node) 2475 && type != dfloat32_type_node) 2476 warning (0, "passing argument %d of %qE as %<float%> " 2477 "rather than %<double%> due to prototype", 2478 argnum, rname); 2479 2480 /* Warn if mismatch between argument and prototype 2481 for decimal float types. Warn of conversions with 2482 binary float types and of precision narrowing due to 2483 prototype. */ 2484 else if (type != TREE_TYPE (val) 2485 && (type == dfloat32_type_node 2486 || type == dfloat64_type_node 2487 || type == dfloat128_type_node 2488 || TREE_TYPE (val) == dfloat32_type_node 2489 || TREE_TYPE (val) == dfloat64_type_node 2490 || TREE_TYPE (val) == dfloat128_type_node) 2491 && (formal_prec 2492 <= TYPE_PRECISION (TREE_TYPE (val)) 2493 || (type == dfloat128_type_node 2494 && (TREE_TYPE (val) 2495 != dfloat64_type_node 2496 && (TREE_TYPE (val) 2497 != dfloat32_type_node))) 2498 || (type == dfloat64_type_node 2499 && (TREE_TYPE (val) 2500 != dfloat32_type_node)))) 2501 warning (0, "passing argument %d of %qE as %qT " 2502 "rather than %qT due to prototype", 2503 argnum, rname, type, TREE_TYPE (val)); 2504 2505 } 2506 /* Detect integer changing in width or signedness. 2507 These warnings are only activated with 2508 -Wconversion, not with -Wtraditional. */ 2509 else if (warn_conversion && INTEGRAL_TYPE_P (type) 2510 && INTEGRAL_TYPE_P (TREE_TYPE (val))) 2511 { 2512 tree would_have_been = default_conversion (val); 2513 tree type1 = TREE_TYPE (would_have_been); 2514 2515 if (TREE_CODE (type) == ENUMERAL_TYPE 2516 && (TYPE_MAIN_VARIANT (type) 2517 == TYPE_MAIN_VARIANT (TREE_TYPE (val)))) 2518 /* No warning if function asks for enum 2519 and the actual arg is that enum type. */ 2520 ; 2521 else if (formal_prec != TYPE_PRECISION (type1)) 2522 warning (OPT_Wconversion, "passing argument %d of %qE " 2523 "with different width due to prototype", 2524 argnum, rname); 2525 else if (TYPE_UNSIGNED (type) == TYPE_UNSIGNED (type1)) 2526 ; 2527 /* Don't complain if the formal parameter type 2528 is an enum, because we can't tell now whether 2529 the value was an enum--even the same enum. */ 2530 else if (TREE_CODE (type) == ENUMERAL_TYPE) 2531 ; 2532 else if (TREE_CODE (val) == INTEGER_CST 2533 && int_fits_type_p (val, type)) 2534 /* Change in signedness doesn't matter 2535 if a constant value is unaffected. */ 2536 ; 2537 /* If the value is extended from a narrower 2538 unsigned type, it doesn't matter whether we 2539 pass it as signed or unsigned; the value 2540 certainly is the same either way. */ 2541 else if (TYPE_PRECISION (TREE_TYPE (val)) < TYPE_PRECISION (type) 2542 && TYPE_UNSIGNED (TREE_TYPE (val))) 2543 ; 2544 else if (TYPE_UNSIGNED (type)) 2545 warning (OPT_Wconversion, "passing argument %d of %qE " 2546 "as unsigned due to prototype", 2547 argnum, rname); 2548 else 2549 warning (OPT_Wconversion, "passing argument %d of %qE " 2550 "as signed due to prototype", argnum, rname); 2551 } 2552 } 2553 2554 parmval = convert_for_assignment (type, val, ic_argpass, 2555 fundecl, function, 2556 parmnum + 1); 2557 2558 if (targetm.calls.promote_prototypes (fundecl ? TREE_TYPE (fundecl) : 0) 2559 && INTEGRAL_TYPE_P (type) 2560 && (TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node))) 2561 parmval = default_conversion (parmval); 2562 } 2563 result = tree_cons (NULL_TREE, parmval, result); 2564 } 2565 else if (TREE_CODE (TREE_TYPE (val)) == REAL_TYPE 2566 && (TYPE_PRECISION (TREE_TYPE (val)) 2567 < TYPE_PRECISION (double_type_node)) 2568 && !DECIMAL_FLOAT_MODE_P (TYPE_MODE (TREE_TYPE (val)))) 2569 /* Convert `float' to `double'. */ 2570 result = tree_cons (NULL_TREE, convert (double_type_node, val), result); 2571 else if ((invalid_func_diag = 2572 targetm.calls.invalid_arg_for_unprototyped_fn (typelist, fundecl, val))) 2573 { 2574 error (invalid_func_diag); 2575 return error_mark_node; 2576 } 2577 else 2578 /* Convert `short' and `char' to full-size `int'. */ 2579 result = tree_cons (NULL_TREE, default_conversion (val), result); 2580 2581 if (typetail) 2582 typetail = TREE_CHAIN (typetail); 2583 } 2584 2585 if (typetail != 0 && TREE_VALUE (typetail) != void_type_node) 2586 { 2587 error ("too few arguments to function %qE", function); 2588 return error_mark_node; 2589 } 2590 2591 return nreverse (result); 2592} 2593 2594/* This is the entry point used by the parser to build unary operators 2595 in the input. CODE, a tree_code, specifies the unary operator, and 2596 ARG is the operand. For unary plus, the C parser currently uses 2597 CONVERT_EXPR for code. */ 2598 2599struct c_expr 2600parser_build_unary_op (enum tree_code code, struct c_expr arg) 2601{ 2602 struct c_expr result; 2603 2604 result.original_code = ERROR_MARK; 2605 result.value = build_unary_op (code, arg.value, 0); 2606 overflow_warning (result.value); 2607 return result; 2608} 2609 2610/* This is the entry point used by the parser to build binary operators 2611 in the input. CODE, a tree_code, specifies the binary operator, and 2612 ARG1 and ARG2 are the operands. In addition to constructing the 2613 expression, we check for operands that were written with other binary 2614 operators in a way that is likely to confuse the user. */ 2615 2616struct c_expr 2617parser_build_binary_op (enum tree_code code, struct c_expr arg1, 2618 struct c_expr arg2) 2619{ 2620 struct c_expr result; 2621 2622 enum tree_code code1 = arg1.original_code; 2623 enum tree_code code2 = arg2.original_code; 2624 2625 result.value = build_binary_op (code, arg1.value, arg2.value, 1); 2626 result.original_code = code; 2627 2628 if (TREE_CODE (result.value) == ERROR_MARK) 2629 return result; 2630 2631 /* Check for cases such as x+y<<z which users are likely 2632 to misinterpret. */ 2633 if (warn_parentheses) 2634 warn_about_parentheses (code, code1, code2); 2635 2636 /* Warn about comparisons against string literals, with the exception 2637 of testing for equality or inequality of a string literal with NULL. */ 2638 if (code == EQ_EXPR || code == NE_EXPR) 2639 { 2640 if ((code1 == STRING_CST && !integer_zerop (arg2.value)) 2641 || (code2 == STRING_CST && !integer_zerop (arg1.value))) 2642 warning (OPT_Waddress, 2643 "comparison with string literal results in unspecified behaviour"); 2644 } 2645 else if (TREE_CODE_CLASS (code) == tcc_comparison 2646 && (code1 == STRING_CST || code2 == STRING_CST)) 2647 warning (OPT_Waddress, 2648 "comparison with string literal results in unspecified behaviour"); 2649 2650 overflow_warning (result.value); 2651 2652 return result; 2653} 2654 2655/* Return a tree for the difference of pointers OP0 and OP1. 2656 The resulting tree has type int. */ 2657 2658static tree 2659pointer_diff (tree op0, tree op1) 2660{ 2661 tree restype = ptrdiff_type_node; 2662 2663 tree target_type = TREE_TYPE (TREE_TYPE (op0)); 2664 tree con0, con1, lit0, lit1; 2665 tree orig_op1 = op1; 2666 2667 if (pedantic || warn_pointer_arith) 2668 { 2669 if (TREE_CODE (target_type) == VOID_TYPE) 2670 pedwarn ("pointer of type %<void *%> used in subtraction"); 2671 if (TREE_CODE (target_type) == FUNCTION_TYPE) 2672 pedwarn ("pointer to a function used in subtraction"); 2673 } 2674 2675 /* If the conversion to ptrdiff_type does anything like widening or 2676 converting a partial to an integral mode, we get a convert_expression 2677 that is in the way to do any simplifications. 2678 (fold-const.c doesn't know that the extra bits won't be needed. 2679 split_tree uses STRIP_SIGN_NOPS, which leaves conversions to a 2680 different mode in place.) 2681 So first try to find a common term here 'by hand'; we want to cover 2682 at least the cases that occur in legal static initializers. */ 2683 if ((TREE_CODE (op0) == NOP_EXPR || TREE_CODE (op0) == CONVERT_EXPR) 2684 && (TYPE_PRECISION (TREE_TYPE (op0)) 2685 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op0, 0))))) 2686 con0 = TREE_OPERAND (op0, 0); 2687 else 2688 con0 = op0; 2689 if ((TREE_CODE (op1) == NOP_EXPR || TREE_CODE (op1) == CONVERT_EXPR) 2690 && (TYPE_PRECISION (TREE_TYPE (op1)) 2691 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op1, 0))))) 2692 con1 = TREE_OPERAND (op1, 0); 2693 else 2694 con1 = op1; 2695 2696 if (TREE_CODE (con0) == PLUS_EXPR) 2697 { 2698 lit0 = TREE_OPERAND (con0, 1); 2699 con0 = TREE_OPERAND (con0, 0); 2700 } 2701 else 2702 lit0 = integer_zero_node; 2703 2704 if (TREE_CODE (con1) == PLUS_EXPR) 2705 { 2706 lit1 = TREE_OPERAND (con1, 1); 2707 con1 = TREE_OPERAND (con1, 0); 2708 } 2709 else 2710 lit1 = integer_zero_node; 2711 2712 if (operand_equal_p (con0, con1, 0)) 2713 { 2714 op0 = lit0; 2715 op1 = lit1; 2716 } 2717 2718 2719 /* First do the subtraction as integers; 2720 then drop through to build the divide operator. 2721 Do not do default conversions on the minus operator 2722 in case restype is a short type. */ 2723 2724 op0 = build_binary_op (MINUS_EXPR, convert (restype, op0), 2725 convert (restype, op1), 0); 2726 /* This generates an error if op1 is pointer to incomplete type. */ 2727 if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (TREE_TYPE (orig_op1)))) 2728 error ("arithmetic on pointer to an incomplete type"); 2729 2730 /* This generates an error if op0 is pointer to incomplete type. */ 2731 op1 = c_size_in_bytes (target_type); 2732 2733 /* Divide by the size, in easiest possible way. */ 2734 return fold_build2 (EXACT_DIV_EXPR, restype, op0, convert (restype, op1)); 2735} 2736 2737/* Construct and perhaps optimize a tree representation 2738 for a unary operation. CODE, a tree_code, specifies the operation 2739 and XARG is the operand. 2740 For any CODE other than ADDR_EXPR, FLAG nonzero suppresses 2741 the default promotions (such as from short to int). 2742 For ADDR_EXPR, the default promotions are not applied; FLAG nonzero 2743 allows non-lvalues; this is only used to handle conversion of non-lvalue 2744 arrays to pointers in C99. */ 2745 2746tree 2747build_unary_op (enum tree_code code, tree xarg, int flag) 2748{ 2749 /* No default_conversion here. It causes trouble for ADDR_EXPR. */ 2750 tree arg = xarg; 2751 tree argtype = 0; 2752 enum tree_code typecode = TREE_CODE (TREE_TYPE (arg)); 2753 tree val; 2754 int noconvert = flag; 2755 const char *invalid_op_diag; 2756 2757 if (typecode == ERROR_MARK) 2758 return error_mark_node; 2759 if (typecode == ENUMERAL_TYPE || typecode == BOOLEAN_TYPE) 2760 typecode = INTEGER_TYPE; 2761 2762 if ((invalid_op_diag 2763 = targetm.invalid_unary_op (code, TREE_TYPE (xarg)))) 2764 { 2765 error (invalid_op_diag); 2766 return error_mark_node; 2767 } 2768 2769 switch (code) 2770 { 2771 case CONVERT_EXPR: 2772 /* This is used for unary plus, because a CONVERT_EXPR 2773 is enough to prevent anybody from looking inside for 2774 associativity, but won't generate any code. */ 2775 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE 2776 || typecode == COMPLEX_TYPE 2777 || typecode == VECTOR_TYPE)) 2778 { 2779 error ("wrong type argument to unary plus"); 2780 return error_mark_node; 2781 } 2782 else if (!noconvert) 2783 arg = default_conversion (arg); 2784 arg = non_lvalue (arg); 2785 break; 2786 2787 case NEGATE_EXPR: 2788 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE 2789 || typecode == COMPLEX_TYPE 2790 || typecode == VECTOR_TYPE)) 2791 { 2792 error ("wrong type argument to unary minus"); 2793 return error_mark_node; 2794 } 2795 else if (!noconvert) 2796 arg = default_conversion (arg); 2797 break; 2798 2799 case BIT_NOT_EXPR: 2800 if (typecode == INTEGER_TYPE || typecode == VECTOR_TYPE) 2801 { 2802 if (!noconvert) 2803 arg = default_conversion (arg); 2804 } 2805 else if (typecode == COMPLEX_TYPE) 2806 { 2807 code = CONJ_EXPR; 2808 if (pedantic) 2809 pedwarn ("ISO C does not support %<~%> for complex conjugation"); 2810 if (!noconvert) 2811 arg = default_conversion (arg); 2812 } 2813 else 2814 { 2815 error ("wrong type argument to bit-complement"); 2816 return error_mark_node; 2817 } 2818 break; 2819 2820 case ABS_EXPR: 2821 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE)) 2822 { 2823 error ("wrong type argument to abs"); 2824 return error_mark_node; 2825 } 2826 else if (!noconvert) 2827 arg = default_conversion (arg); 2828 break; 2829 2830 case CONJ_EXPR: 2831 /* Conjugating a real value is a no-op, but allow it anyway. */ 2832 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE 2833 || typecode == COMPLEX_TYPE)) 2834 { 2835 error ("wrong type argument to conjugation"); 2836 return error_mark_node; 2837 } 2838 else if (!noconvert) 2839 arg = default_conversion (arg); 2840 break; 2841 2842 case TRUTH_NOT_EXPR: 2843 if (typecode != INTEGER_TYPE 2844 && typecode != REAL_TYPE && typecode != POINTER_TYPE 2845 && typecode != COMPLEX_TYPE) 2846 { 2847 error ("wrong type argument to unary exclamation mark"); 2848 return error_mark_node; 2849 } 2850 arg = c_objc_common_truthvalue_conversion (arg); 2851 return invert_truthvalue (arg); 2852 2853 case REALPART_EXPR: 2854 if (TREE_CODE (arg) == COMPLEX_CST) 2855 return TREE_REALPART (arg); 2856 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE) 2857 return fold_build1 (REALPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg); 2858 else 2859 return arg; 2860 2861 case IMAGPART_EXPR: 2862 if (TREE_CODE (arg) == COMPLEX_CST) 2863 return TREE_IMAGPART (arg); 2864 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE) 2865 return fold_build1 (IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg); 2866 else 2867 return convert (TREE_TYPE (arg), integer_zero_node); 2868 2869 case PREINCREMENT_EXPR: 2870 case POSTINCREMENT_EXPR: 2871 case PREDECREMENT_EXPR: 2872 case POSTDECREMENT_EXPR: 2873 2874 /* Increment or decrement the real part of the value, 2875 and don't change the imaginary part. */ 2876 if (typecode == COMPLEX_TYPE) 2877 { 2878 tree real, imag; 2879 2880 if (pedantic) 2881 pedwarn ("ISO C does not support %<++%> and %<--%>" 2882 " on complex types"); 2883 2884 arg = stabilize_reference (arg); 2885 real = build_unary_op (REALPART_EXPR, arg, 1); 2886 imag = build_unary_op (IMAGPART_EXPR, arg, 1); 2887 return build2 (COMPLEX_EXPR, TREE_TYPE (arg), 2888 build_unary_op (code, real, 1), imag); 2889 } 2890 2891 /* Report invalid types. */ 2892 2893 if (typecode != POINTER_TYPE 2894 && typecode != INTEGER_TYPE && typecode != REAL_TYPE) 2895 { 2896 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR) 2897 error ("wrong type argument to increment"); 2898 else 2899 error ("wrong type argument to decrement"); 2900 2901 return error_mark_node; 2902 } 2903 2904 { 2905 tree inc; 2906 tree result_type = TREE_TYPE (arg); 2907 2908 arg = get_unwidened (arg, 0); 2909 argtype = TREE_TYPE (arg); 2910 2911 /* Compute the increment. */ 2912 2913 if (typecode == POINTER_TYPE) 2914 { 2915 /* If pointer target is an undefined struct, 2916 we just cannot know how to do the arithmetic. */ 2917 if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (result_type))) 2918 { 2919 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR) 2920 error ("increment of pointer to unknown structure"); 2921 else 2922 error ("decrement of pointer to unknown structure"); 2923 } 2924 else if ((pedantic || warn_pointer_arith) 2925 && (TREE_CODE (TREE_TYPE (result_type)) == FUNCTION_TYPE 2926 || TREE_CODE (TREE_TYPE (result_type)) == VOID_TYPE)) 2927 { 2928 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR) 2929 pedwarn ("wrong type argument to increment"); 2930 else 2931 pedwarn ("wrong type argument to decrement"); 2932 } 2933 2934 inc = c_size_in_bytes (TREE_TYPE (result_type)); 2935 } 2936 else 2937 inc = integer_one_node; 2938 2939 inc = convert (argtype, inc); 2940 2941 /* Complain about anything else that is not a true lvalue. */ 2942 if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR 2943 || code == POSTINCREMENT_EXPR) 2944 ? lv_increment 2945 : lv_decrement))) 2946 return error_mark_node; 2947 2948 /* Report a read-only lvalue. */ 2949 if (TREE_READONLY (arg)) 2950 { 2951 readonly_error (arg, 2952 ((code == PREINCREMENT_EXPR 2953 || code == POSTINCREMENT_EXPR) 2954 ? lv_increment : lv_decrement)); 2955 return error_mark_node; 2956 } 2957 2958 if (TREE_CODE (TREE_TYPE (arg)) == BOOLEAN_TYPE) 2959 val = boolean_increment (code, arg); 2960 else 2961 val = build2 (code, TREE_TYPE (arg), arg, inc); 2962 TREE_SIDE_EFFECTS (val) = 1; 2963 val = convert (result_type, val); 2964 if (TREE_CODE (val) != code) 2965 TREE_NO_WARNING (val) = 1; 2966 return val; 2967 } 2968 2969 case ADDR_EXPR: 2970 /* Note that this operation never does default_conversion. */ 2971 2972 /* Let &* cancel out to simplify resulting code. */ 2973 if (TREE_CODE (arg) == INDIRECT_REF) 2974 { 2975 /* Don't let this be an lvalue. */ 2976 if (lvalue_p (TREE_OPERAND (arg, 0))) 2977 return non_lvalue (TREE_OPERAND (arg, 0)); 2978 return TREE_OPERAND (arg, 0); 2979 } 2980 2981 /* For &x[y], return x+y */ 2982 if (TREE_CODE (arg) == ARRAY_REF) 2983 { 2984 tree op0 = TREE_OPERAND (arg, 0); 2985 if (!c_mark_addressable (op0)) 2986 return error_mark_node; 2987 return build_binary_op (PLUS_EXPR, 2988 (TREE_CODE (TREE_TYPE (op0)) == ARRAY_TYPE 2989 ? array_to_pointer_conversion (op0) 2990 : op0), 2991 TREE_OPERAND (arg, 1), 1); 2992 } 2993 2994 /* Anything not already handled and not a true memory reference 2995 or a non-lvalue array is an error. */ 2996 else if (typecode != FUNCTION_TYPE && !flag 2997 && !lvalue_or_else (arg, lv_addressof)) 2998 return error_mark_node; 2999 3000 /* Ordinary case; arg is a COMPONENT_REF or a decl. */ 3001 argtype = TREE_TYPE (arg); 3002 3003 /* If the lvalue is const or volatile, merge that into the type 3004 to which the address will point. Note that you can't get a 3005 restricted pointer by taking the address of something, so we 3006 only have to deal with `const' and `volatile' here. */ 3007 if ((DECL_P (arg) || REFERENCE_CLASS_P (arg)) 3008 && (TREE_READONLY (arg) || TREE_THIS_VOLATILE (arg))) 3009 argtype = c_build_type_variant (argtype, 3010 TREE_READONLY (arg), 3011 TREE_THIS_VOLATILE (arg)); 3012 3013 if (!c_mark_addressable (arg)) 3014 return error_mark_node; 3015 3016 gcc_assert (TREE_CODE (arg) != COMPONENT_REF 3017 || !DECL_C_BIT_FIELD (TREE_OPERAND (arg, 1))); 3018 3019 argtype = build_pointer_type (argtype); 3020 3021 /* ??? Cope with user tricks that amount to offsetof. Delete this 3022 when we have proper support for integer constant expressions. */ 3023 val = get_base_address (arg); 3024 if (val && TREE_CODE (val) == INDIRECT_REF 3025 && TREE_CONSTANT (TREE_OPERAND (val, 0))) 3026 { 3027 tree op0 = fold_convert (argtype, fold_offsetof (arg, val)), op1; 3028 3029 op1 = fold_convert (argtype, TREE_OPERAND (val, 0)); 3030 return fold_build2 (PLUS_EXPR, argtype, op0, op1); 3031 } 3032 3033 val = build1 (ADDR_EXPR, argtype, arg); 3034 3035 return val; 3036 3037 default: 3038 gcc_unreachable (); 3039 } 3040 3041 if (argtype == 0) 3042 argtype = TREE_TYPE (arg); 3043 return require_constant_value ? fold_build1_initializer (code, argtype, arg) 3044 : fold_build1 (code, argtype, arg); 3045} 3046 3047/* Return nonzero if REF is an lvalue valid for this language. 3048 Lvalues can be assigned, unless their type has TYPE_READONLY. 3049 Lvalues can have their address taken, unless they have C_DECL_REGISTER. */ 3050 3051static int 3052lvalue_p (tree ref) 3053{ 3054 enum tree_code code = TREE_CODE (ref); 3055 3056 switch (code) 3057 { 3058 case REALPART_EXPR: 3059 case IMAGPART_EXPR: 3060 case COMPONENT_REF: 3061 return lvalue_p (TREE_OPERAND (ref, 0)); 3062 3063 case COMPOUND_LITERAL_EXPR: 3064 case STRING_CST: 3065 return 1; 3066 3067 case INDIRECT_REF: 3068 case ARRAY_REF: 3069 case VAR_DECL: 3070 case PARM_DECL: 3071 case RESULT_DECL: 3072 case ERROR_MARK: 3073 return (TREE_CODE (TREE_TYPE (ref)) != FUNCTION_TYPE 3074 && TREE_CODE (TREE_TYPE (ref)) != METHOD_TYPE); 3075 3076 case BIND_EXPR: 3077 return TREE_CODE (TREE_TYPE (ref)) == ARRAY_TYPE; 3078 3079 default: 3080 return 0; 3081 } 3082} 3083 3084/* Give an error for storing in something that is 'const'. */ 3085 3086static void 3087readonly_error (tree arg, enum lvalue_use use) 3088{ 3089 gcc_assert (use == lv_assign || use == lv_increment || use == lv_decrement 3090 || use == lv_asm); 3091 /* Using this macro rather than (for example) arrays of messages 3092 ensures that all the format strings are checked at compile 3093 time. */ 3094#define READONLY_MSG(A, I, D, AS) (use == lv_assign ? (A) \ 3095 : (use == lv_increment ? (I) \ 3096 : (use == lv_decrement ? (D) : (AS)))) 3097 if (TREE_CODE (arg) == COMPONENT_REF) 3098 { 3099 if (TYPE_READONLY (TREE_TYPE (TREE_OPERAND (arg, 0)))) 3100 readonly_error (TREE_OPERAND (arg, 0), use); 3101 else 3102 error (READONLY_MSG (G_("assignment of read-only member %qD"), 3103 G_("increment of read-only member %qD"), 3104 G_("decrement of read-only member %qD"), 3105 G_("read-only member %qD used as %<asm%> output")), 3106 TREE_OPERAND (arg, 1)); 3107 } 3108 else if (TREE_CODE (arg) == VAR_DECL) 3109 error (READONLY_MSG (G_("assignment of read-only variable %qD"), 3110 G_("increment of read-only variable %qD"), 3111 G_("decrement of read-only variable %qD"), 3112 G_("read-only variable %qD used as %<asm%> output")), 3113 arg); 3114 else 3115 error (READONLY_MSG (G_("assignment of read-only location"), 3116 G_("increment of read-only location"), 3117 G_("decrement of read-only location"), 3118 G_("read-only location used as %<asm%> output"))); 3119} 3120 3121 3122/* Return nonzero if REF is an lvalue valid for this language; 3123 otherwise, print an error message and return zero. USE says 3124 how the lvalue is being used and so selects the error message. */ 3125 3126static int 3127lvalue_or_else (tree ref, enum lvalue_use use) 3128{ 3129 int win = lvalue_p (ref); 3130 3131 if (!win) 3132 lvalue_error (use); 3133 3134 return win; 3135} 3136 3137/* Mark EXP saying that we need to be able to take the 3138 address of it; it should not be allocated in a register. 3139 Returns true if successful. */ 3140 3141bool 3142c_mark_addressable (tree exp) 3143{ 3144 tree x = exp; 3145 3146 while (1) 3147 switch (TREE_CODE (x)) 3148 { 3149 case COMPONENT_REF: 3150 if (DECL_C_BIT_FIELD (TREE_OPERAND (x, 1))) 3151 { 3152 error 3153 ("cannot take address of bit-field %qD", TREE_OPERAND (x, 1)); 3154 return false; 3155 } 3156 3157 /* ... fall through ... */ 3158 3159 case ADDR_EXPR: 3160 case ARRAY_REF: 3161 case REALPART_EXPR: 3162 case IMAGPART_EXPR: 3163 x = TREE_OPERAND (x, 0); 3164 break; 3165 3166 case COMPOUND_LITERAL_EXPR: 3167 case CONSTRUCTOR: 3168 TREE_ADDRESSABLE (x) = 1; 3169 return true; 3170 3171 case VAR_DECL: 3172 case CONST_DECL: 3173 case PARM_DECL: 3174 case RESULT_DECL: 3175 if (C_DECL_REGISTER (x) 3176 && DECL_NONLOCAL (x)) 3177 { 3178 if (TREE_PUBLIC (x) || TREE_STATIC (x) || DECL_EXTERNAL (x)) 3179 { 3180 error 3181 ("global register variable %qD used in nested function", x); 3182 return false; 3183 } 3184 pedwarn ("register variable %qD used in nested function", x); 3185 } 3186 else if (C_DECL_REGISTER (x)) 3187 { 3188 if (TREE_PUBLIC (x) || TREE_STATIC (x) || DECL_EXTERNAL (x)) 3189 error ("address of global register variable %qD requested", x); 3190 else 3191 error ("address of register variable %qD requested", x); 3192 return false; 3193 } 3194 3195 /* drops in */ 3196 case FUNCTION_DECL: 3197 TREE_ADDRESSABLE (x) = 1; 3198 /* drops out */ 3199 default: 3200 return true; 3201 } 3202} 3203 3204/* Build and return a conditional expression IFEXP ? OP1 : OP2. */ 3205 3206tree 3207build_conditional_expr (tree ifexp, tree op1, tree op2) 3208{ 3209 tree type1; 3210 tree type2; 3211 enum tree_code code1; 3212 enum tree_code code2; 3213 tree result_type = NULL; 3214 tree orig_op1 = op1, orig_op2 = op2; 3215 3216 /* Promote both alternatives. */ 3217 3218 if (TREE_CODE (TREE_TYPE (op1)) != VOID_TYPE) 3219 op1 = default_conversion (op1); 3220 if (TREE_CODE (TREE_TYPE (op2)) != VOID_TYPE) 3221 op2 = default_conversion (op2); 3222 3223 if (TREE_CODE (ifexp) == ERROR_MARK 3224 || TREE_CODE (TREE_TYPE (op1)) == ERROR_MARK 3225 || TREE_CODE (TREE_TYPE (op2)) == ERROR_MARK) 3226 return error_mark_node; 3227 3228 type1 = TREE_TYPE (op1); 3229 code1 = TREE_CODE (type1); 3230 type2 = TREE_TYPE (op2); 3231 code2 = TREE_CODE (type2); 3232 3233 /* C90 does not permit non-lvalue arrays in conditional expressions. 3234 In C99 they will be pointers by now. */ 3235 if (code1 == ARRAY_TYPE || code2 == ARRAY_TYPE) 3236 { 3237 error ("non-lvalue array in conditional expression"); 3238 return error_mark_node; 3239 } 3240 3241 /* Quickly detect the usual case where op1 and op2 have the same type 3242 after promotion. */ 3243 if (TYPE_MAIN_VARIANT (type1) == TYPE_MAIN_VARIANT (type2)) 3244 { 3245 if (type1 == type2) 3246 result_type = type1; 3247 else 3248 result_type = TYPE_MAIN_VARIANT (type1); 3249 } 3250 else if ((code1 == INTEGER_TYPE || code1 == REAL_TYPE 3251 || code1 == COMPLEX_TYPE) 3252 && (code2 == INTEGER_TYPE || code2 == REAL_TYPE 3253 || code2 == COMPLEX_TYPE)) 3254 { 3255 result_type = c_common_type (type1, type2); 3256 3257 /* If -Wsign-compare, warn here if type1 and type2 have 3258 different signedness. We'll promote the signed to unsigned 3259 and later code won't know it used to be different. 3260 Do this check on the original types, so that explicit casts 3261 will be considered, but default promotions won't. */ 3262 if (warn_sign_compare && !skip_evaluation) 3263 { 3264 int unsigned_op1 = TYPE_UNSIGNED (TREE_TYPE (orig_op1)); 3265 int unsigned_op2 = TYPE_UNSIGNED (TREE_TYPE (orig_op2)); 3266 3267 if (unsigned_op1 ^ unsigned_op2) 3268 { 3269 bool ovf; 3270 3271 /* Do not warn if the result type is signed, since the 3272 signed type will only be chosen if it can represent 3273 all the values of the unsigned type. */ 3274 if (!TYPE_UNSIGNED (result_type)) 3275 /* OK */; 3276 /* Do not warn if the signed quantity is an unsuffixed 3277 integer literal (or some static constant expression 3278 involving such literals) and it is non-negative. */ 3279 else if ((unsigned_op2 3280 && tree_expr_nonnegative_warnv_p (op1, &ovf)) 3281 || (unsigned_op1 3282 && tree_expr_nonnegative_warnv_p (op2, &ovf))) 3283 /* OK */; 3284 else 3285 warning (0, "signed and unsigned type in conditional expression"); 3286 } 3287 } 3288 } 3289 else if (code1 == VOID_TYPE || code2 == VOID_TYPE) 3290 { 3291 if (pedantic && (code1 != VOID_TYPE || code2 != VOID_TYPE)) 3292 pedwarn ("ISO C forbids conditional expr with only one void side"); 3293 result_type = void_type_node; 3294 } 3295 else if (code1 == POINTER_TYPE && code2 == POINTER_TYPE) 3296 { 3297 if (comp_target_types (type1, type2)) 3298 result_type = common_pointer_type (type1, type2); 3299 else if (null_pointer_constant_p (orig_op1)) 3300 result_type = qualify_type (type2, type1); 3301 else if (null_pointer_constant_p (orig_op2)) 3302 result_type = qualify_type (type1, type2); 3303 else if (VOID_TYPE_P (TREE_TYPE (type1))) 3304 { 3305 if (pedantic && TREE_CODE (TREE_TYPE (type2)) == FUNCTION_TYPE) 3306 pedwarn ("ISO C forbids conditional expr between " 3307 "%<void *%> and function pointer"); 3308 result_type = build_pointer_type (qualify_type (TREE_TYPE (type1), 3309 TREE_TYPE (type2))); 3310 } 3311 else if (VOID_TYPE_P (TREE_TYPE (type2))) 3312 { 3313 if (pedantic && TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE) 3314 pedwarn ("ISO C forbids conditional expr between " 3315 "%<void *%> and function pointer"); 3316 result_type = build_pointer_type (qualify_type (TREE_TYPE (type2), 3317 TREE_TYPE (type1))); 3318 } 3319 else 3320 { 3321 pedwarn ("pointer type mismatch in conditional expression"); 3322 result_type = build_pointer_type (void_type_node); 3323 } 3324 } 3325 else if (code1 == POINTER_TYPE && code2 == INTEGER_TYPE) 3326 { 3327 if (!null_pointer_constant_p (orig_op2)) 3328 pedwarn ("pointer/integer type mismatch in conditional expression"); 3329 else 3330 { 3331 op2 = null_pointer_node; 3332 } 3333 result_type = type1; 3334 } 3335 else if (code2 == POINTER_TYPE && code1 == INTEGER_TYPE) 3336 { 3337 if (!null_pointer_constant_p (orig_op1)) 3338 pedwarn ("pointer/integer type mismatch in conditional expression"); 3339 else 3340 { 3341 op1 = null_pointer_node; 3342 } 3343 result_type = type2; 3344 } 3345 3346 if (!result_type) 3347 { 3348 if (flag_cond_mismatch) 3349 result_type = void_type_node; 3350 else 3351 { 3352 error ("type mismatch in conditional expression"); 3353 return error_mark_node; 3354 } 3355 } 3356 3357 /* Merge const and volatile flags of the incoming types. */ 3358 result_type 3359 = build_type_variant (result_type, 3360 TREE_READONLY (op1) || TREE_READONLY (op2), 3361 TREE_THIS_VOLATILE (op1) || TREE_THIS_VOLATILE (op2)); 3362 3363 if (result_type != TREE_TYPE (op1)) 3364 op1 = convert_and_check (result_type, op1); 3365 if (result_type != TREE_TYPE (op2)) 3366 op2 = convert_and_check (result_type, op2); 3367 3368 return fold_build3 (COND_EXPR, result_type, ifexp, op1, op2); 3369} 3370 3371/* Return a compound expression that performs two expressions and 3372 returns the value of the second of them. */ 3373 3374tree 3375build_compound_expr (tree expr1, tree expr2) 3376{ 3377 if (!TREE_SIDE_EFFECTS (expr1)) 3378 { 3379 /* The left-hand operand of a comma expression is like an expression 3380 statement: with -Wextra or -Wunused, we should warn if it doesn't have 3381 any side-effects, unless it was explicitly cast to (void). */ 3382 if (warn_unused_value) 3383 { 3384 if (VOID_TYPE_P (TREE_TYPE (expr1)) 3385 && (TREE_CODE (expr1) == NOP_EXPR 3386 || TREE_CODE (expr1) == CONVERT_EXPR)) 3387 ; /* (void) a, b */ 3388 else if (VOID_TYPE_P (TREE_TYPE (expr1)) 3389 && TREE_CODE (expr1) == COMPOUND_EXPR 3390 && (TREE_CODE (TREE_OPERAND (expr1, 1)) == CONVERT_EXPR 3391 || TREE_CODE (TREE_OPERAND (expr1, 1)) == NOP_EXPR)) 3392 ; /* (void) a, (void) b, c */ 3393 else 3394 warning (0, "left-hand operand of comma expression has no effect"); 3395 } 3396 } 3397 3398 /* With -Wunused, we should also warn if the left-hand operand does have 3399 side-effects, but computes a value which is not used. For example, in 3400 `foo() + bar(), baz()' the result of the `+' operator is not used, 3401 so we should issue a warning. */ 3402 else if (warn_unused_value) 3403 warn_if_unused_value (expr1, input_location); 3404 3405 if (expr2 == error_mark_node) 3406 return error_mark_node; 3407 3408 return build2 (COMPOUND_EXPR, TREE_TYPE (expr2), expr1, expr2); 3409} 3410 3411/* Build an expression representing a cast to type TYPE of expression EXPR. */ 3412 3413tree 3414build_c_cast (tree type, tree expr) 3415{ 3416 tree value = expr; 3417 3418 if (type == error_mark_node || expr == error_mark_node) 3419 return error_mark_node; 3420 3421 /* The ObjC front-end uses TYPE_MAIN_VARIANT to tie together types differing 3422 only in <protocol> qualifications. But when constructing cast expressions, 3423 the protocols do matter and must be kept around. */ 3424 if (objc_is_object_ptr (type) && objc_is_object_ptr (TREE_TYPE (expr))) 3425 return build1 (NOP_EXPR, type, expr); 3426 3427 type = TYPE_MAIN_VARIANT (type); 3428 3429 if (TREE_CODE (type) == ARRAY_TYPE) 3430 { 3431 error ("cast specifies array type"); 3432 return error_mark_node; 3433 } 3434 3435 if (TREE_CODE (type) == FUNCTION_TYPE) 3436 { 3437 error ("cast specifies function type"); 3438 return error_mark_node; 3439 } 3440 3441 if (type == TYPE_MAIN_VARIANT (TREE_TYPE (value))) 3442 { 3443 if (pedantic) 3444 { 3445 if (TREE_CODE (type) == RECORD_TYPE 3446 || TREE_CODE (type) == UNION_TYPE) 3447 pedwarn ("ISO C forbids casting nonscalar to the same type"); 3448 } 3449 } 3450 else if (TREE_CODE (type) == UNION_TYPE) 3451 { 3452 tree field; 3453 3454 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field)) 3455 if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (field)), 3456 TYPE_MAIN_VARIANT (TREE_TYPE (value)))) 3457 break; 3458 3459 if (field) 3460 { 3461 tree t; 3462 3463 if (pedantic) 3464 pedwarn ("ISO C forbids casts to union type"); 3465 t = digest_init (type, 3466 build_constructor_single (type, field, value), 3467 true, 0); 3468 TREE_CONSTANT (t) = TREE_CONSTANT (value); 3469 TREE_INVARIANT (t) = TREE_INVARIANT (value); 3470 return t; 3471 } 3472 error ("cast to union type from type not present in union"); 3473 return error_mark_node; 3474 } 3475 else 3476 { 3477 tree otype, ovalue; 3478 3479 if (type == void_type_node) 3480 return build1 (CONVERT_EXPR, type, value); 3481 3482 otype = TREE_TYPE (value); 3483 3484 /* Optionally warn about potentially worrisome casts. */ 3485 3486 if (warn_cast_qual 3487 && TREE_CODE (type) == POINTER_TYPE 3488 && TREE_CODE (otype) == POINTER_TYPE) 3489 { 3490 tree in_type = type; 3491 tree in_otype = otype; 3492 int added = 0; 3493 int discarded = 0; 3494 3495 /* Check that the qualifiers on IN_TYPE are a superset of 3496 the qualifiers of IN_OTYPE. The outermost level of 3497 POINTER_TYPE nodes is uninteresting and we stop as soon 3498 as we hit a non-POINTER_TYPE node on either type. */ 3499 do 3500 { 3501 in_otype = TREE_TYPE (in_otype); 3502 in_type = TREE_TYPE (in_type); 3503 3504 /* GNU C allows cv-qualified function types. 'const' 3505 means the function is very pure, 'volatile' means it 3506 can't return. We need to warn when such qualifiers 3507 are added, not when they're taken away. */ 3508 if (TREE_CODE (in_otype) == FUNCTION_TYPE 3509 && TREE_CODE (in_type) == FUNCTION_TYPE) 3510 added |= (TYPE_QUALS (in_type) & ~TYPE_QUALS (in_otype)); 3511 else 3512 discarded |= (TYPE_QUALS (in_otype) & ~TYPE_QUALS (in_type)); 3513 } 3514 while (TREE_CODE (in_type) == POINTER_TYPE 3515 && TREE_CODE (in_otype) == POINTER_TYPE); 3516 3517 if (added) 3518 warning (0, "cast adds new qualifiers to function type"); 3519 3520 if (discarded) 3521 /* There are qualifiers present in IN_OTYPE that are not 3522 present in IN_TYPE. */ 3523 warning (0, "cast discards qualifiers from pointer target type"); 3524 } 3525 3526 /* Warn about possible alignment problems. */ 3527 if (STRICT_ALIGNMENT 3528 && TREE_CODE (type) == POINTER_TYPE 3529 && TREE_CODE (otype) == POINTER_TYPE 3530 && TREE_CODE (TREE_TYPE (otype)) != VOID_TYPE 3531 && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE 3532 /* Don't warn about opaque types, where the actual alignment 3533 restriction is unknown. */ 3534 && !((TREE_CODE (TREE_TYPE (otype)) == UNION_TYPE 3535 || TREE_CODE (TREE_TYPE (otype)) == RECORD_TYPE) 3536 && TYPE_MODE (TREE_TYPE (otype)) == VOIDmode) 3537 && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (otype))) 3538 warning (OPT_Wcast_align, 3539 "cast increases required alignment of target type"); 3540 3541 if (TREE_CODE (type) == INTEGER_TYPE 3542 && TREE_CODE (otype) == POINTER_TYPE 3543 && TYPE_PRECISION (type) != TYPE_PRECISION (otype)) 3544 /* Unlike conversion of integers to pointers, where the 3545 warning is disabled for converting constants because 3546 of cases such as SIG_*, warn about converting constant 3547 pointers to integers. In some cases it may cause unwanted 3548 sign extension, and a warning is appropriate. */ 3549 warning (OPT_Wpointer_to_int_cast, 3550 "cast from pointer to integer of different size"); 3551 3552 if (TREE_CODE (value) == CALL_EXPR 3553 && TREE_CODE (type) != TREE_CODE (otype)) 3554 warning (OPT_Wbad_function_cast, "cast from function call of type %qT " 3555 "to non-matching type %qT", otype, type); 3556 3557 if (TREE_CODE (type) == POINTER_TYPE 3558 && TREE_CODE (otype) == INTEGER_TYPE 3559 && TYPE_PRECISION (type) != TYPE_PRECISION (otype) 3560 /* Don't warn about converting any constant. */ 3561 && !TREE_CONSTANT (value)) 3562 warning (OPT_Wint_to_pointer_cast, "cast to pointer from integer " 3563 "of different size"); 3564 3565 strict_aliasing_warning (otype, type, expr); 3566 3567 /* If pedantic, warn for conversions between function and object 3568 pointer types, except for converting a null pointer constant 3569 to function pointer type. */ 3570 if (pedantic 3571 && TREE_CODE (type) == POINTER_TYPE 3572 && TREE_CODE (otype) == POINTER_TYPE 3573 && TREE_CODE (TREE_TYPE (otype)) == FUNCTION_TYPE 3574 && TREE_CODE (TREE_TYPE (type)) != FUNCTION_TYPE) 3575 pedwarn ("ISO C forbids conversion of function pointer to object pointer type"); 3576 3577 if (pedantic 3578 && TREE_CODE (type) == POINTER_TYPE 3579 && TREE_CODE (otype) == POINTER_TYPE 3580 && TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE 3581 && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE 3582 && !null_pointer_constant_p (value)) 3583 pedwarn ("ISO C forbids conversion of object pointer to function pointer type"); 3584 3585 ovalue = value; 3586 value = convert (type, value); 3587 3588 /* Ignore any integer overflow caused by the cast. */ 3589 if (TREE_CODE (value) == INTEGER_CST) 3590 { 3591 if (CONSTANT_CLASS_P (ovalue) 3592 && (TREE_OVERFLOW (ovalue) || TREE_CONSTANT_OVERFLOW (ovalue))) 3593 { 3594 /* Avoid clobbering a shared constant. */ 3595 value = copy_node (value); 3596 TREE_OVERFLOW (value) = TREE_OVERFLOW (ovalue); 3597 TREE_CONSTANT_OVERFLOW (value) = TREE_CONSTANT_OVERFLOW (ovalue); 3598 } 3599 else if (TREE_OVERFLOW (value) || TREE_CONSTANT_OVERFLOW (value)) 3600 /* Reset VALUE's overflow flags, ensuring constant sharing. */ 3601 value = build_int_cst_wide (TREE_TYPE (value), 3602 TREE_INT_CST_LOW (value), 3603 TREE_INT_CST_HIGH (value)); 3604 } 3605 } 3606 3607 /* Don't let a cast be an lvalue. */ 3608 if (value == expr) 3609 value = non_lvalue (value); 3610 3611 return value; 3612} 3613 3614/* Interpret a cast of expression EXPR to type TYPE. */ 3615tree 3616c_cast_expr (struct c_type_name *type_name, tree expr) 3617{ 3618 tree type; 3619 int saved_wsp = warn_strict_prototypes; 3620 3621 /* This avoids warnings about unprototyped casts on 3622 integers. E.g. "#define SIG_DFL (void(*)())0". */ 3623 if (TREE_CODE (expr) == INTEGER_CST) 3624 warn_strict_prototypes = 0; 3625 type = groktypename (type_name); 3626 warn_strict_prototypes = saved_wsp; 3627 3628 return build_c_cast (type, expr); 3629} 3630 3631/* Build an assignment expression of lvalue LHS from value RHS. 3632 MODIFYCODE is the code for a binary operator that we use 3633 to combine the old value of LHS with RHS to get the new value. 3634 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment. */ 3635 3636tree 3637build_modify_expr (tree lhs, enum tree_code modifycode, tree rhs) 3638{ 3639 tree result; 3640 tree newrhs; 3641 tree lhstype = TREE_TYPE (lhs); 3642 tree olhstype = lhstype; 3643 3644 /* Types that aren't fully specified cannot be used in assignments. */ 3645 lhs = require_complete_type (lhs); 3646 3647 /* Avoid duplicate error messages from operands that had errors. */ 3648 if (TREE_CODE (lhs) == ERROR_MARK || TREE_CODE (rhs) == ERROR_MARK) 3649 return error_mark_node; 3650 3651 if (!lvalue_or_else (lhs, lv_assign)) 3652 return error_mark_node; 3653 3654 STRIP_TYPE_NOPS (rhs); 3655 3656 newrhs = rhs; 3657 3658 /* If a binary op has been requested, combine the old LHS value with the RHS 3659 producing the value we should actually store into the LHS. */ 3660 3661 if (modifycode != NOP_EXPR) 3662 { 3663 lhs = stabilize_reference (lhs); 3664 newrhs = build_binary_op (modifycode, lhs, rhs, 1); 3665 } 3666 3667 /* Give an error for storing in something that is 'const'. */ 3668 3669 if (TREE_READONLY (lhs) || TYPE_READONLY (lhstype) 3670 || ((TREE_CODE (lhstype) == RECORD_TYPE 3671 || TREE_CODE (lhstype) == UNION_TYPE) 3672 && C_TYPE_FIELDS_READONLY (lhstype))) 3673 { 3674 readonly_error (lhs, lv_assign); 3675 return error_mark_node; 3676 } 3677 3678 /* If storing into a structure or union member, 3679 it has probably been given type `int'. 3680 Compute the type that would go with 3681 the actual amount of storage the member occupies. */ 3682 3683 if (TREE_CODE (lhs) == COMPONENT_REF 3684 && (TREE_CODE (lhstype) == INTEGER_TYPE 3685 || TREE_CODE (lhstype) == BOOLEAN_TYPE 3686 || TREE_CODE (lhstype) == REAL_TYPE 3687 || TREE_CODE (lhstype) == ENUMERAL_TYPE)) 3688 lhstype = TREE_TYPE (get_unwidened (lhs, 0)); 3689 3690 /* If storing in a field that is in actuality a short or narrower than one, 3691 we must store in the field in its actual type. */ 3692 3693 if (lhstype != TREE_TYPE (lhs)) 3694 { 3695 lhs = copy_node (lhs); 3696 TREE_TYPE (lhs) = lhstype; 3697 } 3698 3699 /* Convert new value to destination type. */ 3700 3701 newrhs = convert_for_assignment (lhstype, newrhs, ic_assign, 3702 NULL_TREE, NULL_TREE, 0); 3703 if (TREE_CODE (newrhs) == ERROR_MARK) 3704 return error_mark_node; 3705 3706 /* Emit ObjC write barrier, if necessary. */ 3707 if (c_dialect_objc () && flag_objc_gc) 3708 { 3709 result = objc_generate_write_barrier (lhs, modifycode, newrhs); 3710 if (result) 3711 return result; 3712 } 3713 3714 /* Scan operands. */ 3715 3716 result = build2 (MODIFY_EXPR, lhstype, lhs, newrhs); 3717 TREE_SIDE_EFFECTS (result) = 1; 3718 3719 /* If we got the LHS in a different type for storing in, 3720 convert the result back to the nominal type of LHS 3721 so that the value we return always has the same type 3722 as the LHS argument. */ 3723 3724 if (olhstype == TREE_TYPE (result)) 3725 return result; 3726 return convert_for_assignment (olhstype, result, ic_assign, 3727 NULL_TREE, NULL_TREE, 0); 3728} 3729 3730/* Convert value RHS to type TYPE as preparation for an assignment 3731 to an lvalue of type TYPE. 3732 The real work of conversion is done by `convert'. 3733 The purpose of this function is to generate error messages 3734 for assignments that are not allowed in C. 3735 ERRTYPE says whether it is argument passing, assignment, 3736 initialization or return. 3737 3738 FUNCTION is a tree for the function being called. 3739 PARMNUM is the number of the argument, for printing in error messages. */ 3740 3741static tree 3742convert_for_assignment (tree type, tree rhs, enum impl_conv errtype, 3743 tree fundecl, tree function, int parmnum) 3744{ 3745 enum tree_code codel = TREE_CODE (type); 3746 tree rhstype; 3747 enum tree_code coder; 3748 tree rname = NULL_TREE; 3749 bool objc_ok = false; 3750 3751 if (errtype == ic_argpass || errtype == ic_argpass_nonproto) 3752 { 3753 tree selector; 3754 /* Change pointer to function to the function itself for 3755 diagnostics. */ 3756 if (TREE_CODE (function) == ADDR_EXPR 3757 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL) 3758 function = TREE_OPERAND (function, 0); 3759 3760 /* Handle an ObjC selector specially for diagnostics. */ 3761 selector = objc_message_selector (); 3762 rname = function; 3763 if (selector && parmnum > 2) 3764 { 3765 rname = selector; 3766 parmnum -= 2; 3767 } 3768 } 3769 3770 /* This macro is used to emit diagnostics to ensure that all format 3771 strings are complete sentences, visible to gettext and checked at 3772 compile time. */ 3773#define WARN_FOR_ASSIGNMENT(AR, AS, IN, RE) \ 3774 do { \ 3775 switch (errtype) \ 3776 { \ 3777 case ic_argpass: \ 3778 pedwarn (AR, parmnum, rname); \ 3779 break; \ 3780 case ic_argpass_nonproto: \ 3781 warning (0, AR, parmnum, rname); \ 3782 break; \ 3783 case ic_assign: \ 3784 pedwarn (AS); \ 3785 break; \ 3786 case ic_init: \ 3787 pedwarn (IN); \ 3788 break; \ 3789 case ic_return: \ 3790 pedwarn (RE); \ 3791 break; \ 3792 default: \ 3793 gcc_unreachable (); \ 3794 } \ 3795 } while (0) 3796 3797 STRIP_TYPE_NOPS (rhs); 3798 3799 if (optimize && TREE_CODE (rhs) == VAR_DECL 3800 && TREE_CODE (TREE_TYPE (rhs)) != ARRAY_TYPE) 3801 rhs = decl_constant_value_for_broken_optimization (rhs); 3802 3803 rhstype = TREE_TYPE (rhs); 3804 coder = TREE_CODE (rhstype); 3805 3806 if (coder == ERROR_MARK) 3807 return error_mark_node; 3808 3809 if (c_dialect_objc ()) 3810 { 3811 int parmno; 3812 3813 switch (errtype) 3814 { 3815 case ic_return: 3816 parmno = 0; 3817 break; 3818 3819 case ic_assign: 3820 parmno = -1; 3821 break; 3822 3823 case ic_init: 3824 parmno = -2; 3825 break; 3826 3827 default: 3828 parmno = parmnum; 3829 break; 3830 } 3831 3832 objc_ok = objc_compare_types (type, rhstype, parmno, rname); 3833 } 3834 3835 if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (rhstype)) 3836 { 3837 overflow_warning (rhs); 3838 return rhs; 3839 } 3840 3841 if (coder == VOID_TYPE) 3842 { 3843 /* Except for passing an argument to an unprototyped function, 3844 this is a constraint violation. When passing an argument to 3845 an unprototyped function, it is compile-time undefined; 3846 making it a constraint in that case was rejected in 3847 DR#252. */ 3848 error ("void value not ignored as it ought to be"); 3849 return error_mark_node; 3850 } 3851 /* A type converts to a reference to it. 3852 This code doesn't fully support references, it's just for the 3853 special case of va_start and va_copy. */ 3854 if (codel == REFERENCE_TYPE 3855 && comptypes (TREE_TYPE (type), TREE_TYPE (rhs)) == 1) 3856 { 3857 if (!lvalue_p (rhs)) 3858 { 3859 error ("cannot pass rvalue to reference parameter"); 3860 return error_mark_node; 3861 } 3862 if (!c_mark_addressable (rhs)) 3863 return error_mark_node; 3864 rhs = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (rhs)), rhs); 3865 3866 /* We already know that these two types are compatible, but they 3867 may not be exactly identical. In fact, `TREE_TYPE (type)' is 3868 likely to be __builtin_va_list and `TREE_TYPE (rhs)' is 3869 likely to be va_list, a typedef to __builtin_va_list, which 3870 is different enough that it will cause problems later. */ 3871 if (TREE_TYPE (TREE_TYPE (rhs)) != TREE_TYPE (type)) 3872 rhs = build1 (NOP_EXPR, build_pointer_type (TREE_TYPE (type)), rhs); 3873 3874 rhs = build1 (NOP_EXPR, type, rhs); 3875 return rhs; 3876 } 3877 /* Some types can interconvert without explicit casts. */ 3878 else if (codel == VECTOR_TYPE && coder == VECTOR_TYPE 3879 && vector_types_convertible_p (type, TREE_TYPE (rhs))) 3880 return convert (type, rhs); 3881 /* Arithmetic types all interconvert, and enum is treated like int. */ 3882 else if ((codel == INTEGER_TYPE || codel == REAL_TYPE 3883 || codel == ENUMERAL_TYPE || codel == COMPLEX_TYPE 3884 || codel == BOOLEAN_TYPE) 3885 && (coder == INTEGER_TYPE || coder == REAL_TYPE 3886 || coder == ENUMERAL_TYPE || coder == COMPLEX_TYPE 3887 || coder == BOOLEAN_TYPE)) 3888 return convert_and_check (type, rhs); 3889 3890 /* Aggregates in different TUs might need conversion. */ 3891 if ((codel == RECORD_TYPE || codel == UNION_TYPE) 3892 && codel == coder 3893 && comptypes (type, rhstype)) 3894 return convert_and_check (type, rhs); 3895 3896 /* Conversion to a transparent union from its member types. 3897 This applies only to function arguments. */ 3898 if (codel == UNION_TYPE && TYPE_TRANSPARENT_UNION (type) 3899 && (errtype == ic_argpass || errtype == ic_argpass_nonproto)) 3900 { 3901 tree memb, marginal_memb = NULL_TREE; 3902 3903 for (memb = TYPE_FIELDS (type); memb ; memb = TREE_CHAIN (memb)) 3904 { 3905 tree memb_type = TREE_TYPE (memb); 3906 3907 if (comptypes (TYPE_MAIN_VARIANT (memb_type), 3908 TYPE_MAIN_VARIANT (rhstype))) 3909 break; 3910 3911 if (TREE_CODE (memb_type) != POINTER_TYPE) 3912 continue; 3913 3914 if (coder == POINTER_TYPE) 3915 { 3916 tree ttl = TREE_TYPE (memb_type); 3917 tree ttr = TREE_TYPE (rhstype); 3918 3919 /* Any non-function converts to a [const][volatile] void * 3920 and vice versa; otherwise, targets must be the same. 3921 Meanwhile, the lhs target must have all the qualifiers of 3922 the rhs. */ 3923 if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr) 3924 || comp_target_types (memb_type, rhstype)) 3925 { 3926 /* If this type won't generate any warnings, use it. */ 3927 if (TYPE_QUALS (ttl) == TYPE_QUALS (ttr) 3928 || ((TREE_CODE (ttr) == FUNCTION_TYPE 3929 && TREE_CODE (ttl) == FUNCTION_TYPE) 3930 ? ((TYPE_QUALS (ttl) | TYPE_QUALS (ttr)) 3931 == TYPE_QUALS (ttr)) 3932 : ((TYPE_QUALS (ttl) | TYPE_QUALS (ttr)) 3933 == TYPE_QUALS (ttl)))) 3934 break; 3935 3936 /* Keep looking for a better type, but remember this one. */ 3937 if (!marginal_memb) 3938 marginal_memb = memb; 3939 } 3940 } 3941 3942 /* Can convert integer zero to any pointer type. */ 3943 if (null_pointer_constant_p (rhs)) 3944 { 3945 rhs = null_pointer_node; 3946 break; 3947 } 3948 } 3949 3950 if (memb || marginal_memb) 3951 { 3952 if (!memb) 3953 { 3954 /* We have only a marginally acceptable member type; 3955 it needs a warning. */ 3956 tree ttl = TREE_TYPE (TREE_TYPE (marginal_memb)); 3957 tree ttr = TREE_TYPE (rhstype); 3958 3959 /* Const and volatile mean something different for function 3960 types, so the usual warnings are not appropriate. */ 3961 if (TREE_CODE (ttr) == FUNCTION_TYPE 3962 && TREE_CODE (ttl) == FUNCTION_TYPE) 3963 { 3964 /* Because const and volatile on functions are 3965 restrictions that say the function will not do 3966 certain things, it is okay to use a const or volatile 3967 function where an ordinary one is wanted, but not 3968 vice-versa. */ 3969 if (TYPE_QUALS (ttl) & ~TYPE_QUALS (ttr)) 3970 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE " 3971 "makes qualified function " 3972 "pointer from unqualified"), 3973 G_("assignment makes qualified " 3974 "function pointer from " 3975 "unqualified"), 3976 G_("initialization makes qualified " 3977 "function pointer from " 3978 "unqualified"), 3979 G_("return makes qualified function " 3980 "pointer from unqualified")); 3981 } 3982 else if (TYPE_QUALS (ttr) & ~TYPE_QUALS (ttl)) 3983 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE discards " 3984 "qualifiers from pointer target type"), 3985 G_("assignment discards qualifiers " 3986 "from pointer target type"), 3987 G_("initialization discards qualifiers " 3988 "from pointer target type"), 3989 G_("return discards qualifiers from " 3990 "pointer target type")); 3991 3992 memb = marginal_memb; 3993 } 3994 3995 if (pedantic && (!fundecl || !DECL_IN_SYSTEM_HEADER (fundecl))) 3996 pedwarn ("ISO C prohibits argument conversion to union type"); 3997 3998 return build_constructor_single (type, memb, rhs); 3999 } 4000 } 4001 4002 /* Conversions among pointers */ 4003 else if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE) 4004 && (coder == codel)) 4005 { 4006 tree ttl = TREE_TYPE (type); 4007 tree ttr = TREE_TYPE (rhstype); 4008 tree mvl = ttl; 4009 tree mvr = ttr; 4010 bool is_opaque_pointer; 4011 int target_cmp = 0; /* Cache comp_target_types () result. */ 4012 4013 if (TREE_CODE (mvl) != ARRAY_TYPE) 4014 mvl = TYPE_MAIN_VARIANT (mvl); 4015 if (TREE_CODE (mvr) != ARRAY_TYPE) 4016 mvr = TYPE_MAIN_VARIANT (mvr); 4017 /* Opaque pointers are treated like void pointers. */ 4018 is_opaque_pointer = (targetm.vector_opaque_p (type) 4019 || targetm.vector_opaque_p (rhstype)) 4020 && TREE_CODE (ttl) == VECTOR_TYPE 4021 && TREE_CODE (ttr) == VECTOR_TYPE; 4022 4023 /* C++ does not allow the implicit conversion void* -> T*. However, 4024 for the purpose of reducing the number of false positives, we 4025 tolerate the special case of 4026 4027 int *p = NULL; 4028 4029 where NULL is typically defined in C to be '(void *) 0'. */ 4030 if (VOID_TYPE_P (ttr) && rhs != null_pointer_node && !VOID_TYPE_P (ttl)) 4031 warning (OPT_Wc___compat, "request for implicit conversion from " 4032 "%qT to %qT not permitted in C++", rhstype, type); 4033 4034 /* Check if the right-hand side has a format attribute but the 4035 left-hand side doesn't. */ 4036 if (warn_missing_format_attribute 4037 && check_missing_format_attribute (type, rhstype)) 4038 { 4039 switch (errtype) 4040 { 4041 case ic_argpass: 4042 case ic_argpass_nonproto: 4043 warning (OPT_Wmissing_format_attribute, 4044 "argument %d of %qE might be " 4045 "a candidate for a format attribute", 4046 parmnum, rname); 4047 break; 4048 case ic_assign: 4049 warning (OPT_Wmissing_format_attribute, 4050 "assignment left-hand side might be " 4051 "a candidate for a format attribute"); 4052 break; 4053 case ic_init: 4054 warning (OPT_Wmissing_format_attribute, 4055 "initialization left-hand side might be " 4056 "a candidate for a format attribute"); 4057 break; 4058 case ic_return: 4059 warning (OPT_Wmissing_format_attribute, 4060 "return type might be " 4061 "a candidate for a format attribute"); 4062 break; 4063 default: 4064 gcc_unreachable (); 4065 } 4066 } 4067 4068 /* Any non-function converts to a [const][volatile] void * 4069 and vice versa; otherwise, targets must be the same. 4070 Meanwhile, the lhs target must have all the qualifiers of the rhs. */ 4071 if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr) 4072 || (target_cmp = comp_target_types (type, rhstype)) 4073 || is_opaque_pointer 4074 || (c_common_unsigned_type (mvl) 4075 == c_common_unsigned_type (mvr))) 4076 { 4077 if (pedantic 4078 && ((VOID_TYPE_P (ttl) && TREE_CODE (ttr) == FUNCTION_TYPE) 4079 || 4080 (VOID_TYPE_P (ttr) 4081 && !null_pointer_constant_p (rhs) 4082 && TREE_CODE (ttl) == FUNCTION_TYPE))) 4083 WARN_FOR_ASSIGNMENT (G_("ISO C forbids passing argument %d of " 4084 "%qE between function pointer " 4085 "and %<void *%>"), 4086 G_("ISO C forbids assignment between " 4087 "function pointer and %<void *%>"), 4088 G_("ISO C forbids initialization between " 4089 "function pointer and %<void *%>"), 4090 G_("ISO C forbids return between function " 4091 "pointer and %<void *%>")); 4092 /* Const and volatile mean something different for function types, 4093 so the usual warnings are not appropriate. */ 4094 else if (TREE_CODE (ttr) != FUNCTION_TYPE 4095 && TREE_CODE (ttl) != FUNCTION_TYPE) 4096 { 4097 if (TYPE_QUALS (ttr) & ~TYPE_QUALS (ttl)) 4098 { 4099 /* Types differing only by the presence of the 'volatile' 4100 qualifier are acceptable if the 'volatile' has been added 4101 in by the Objective-C EH machinery. */ 4102 if (!objc_type_quals_match (ttl, ttr)) 4103 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE discards " 4104 "qualifiers from pointer target type"), 4105 G_("assignment discards qualifiers " 4106 "from pointer target type"), 4107 G_("initialization discards qualifiers " 4108 "from pointer target type"), 4109 G_("return discards qualifiers from " 4110 "pointer target type")); 4111 } 4112 /* If this is not a case of ignoring a mismatch in signedness, 4113 no warning. */ 4114 else if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr) 4115 || target_cmp) 4116 ; 4117 /* If there is a mismatch, do warn. */ 4118 else if (warn_pointer_sign) 4119 WARN_FOR_ASSIGNMENT (G_("pointer targets in passing argument " 4120 "%d of %qE differ in signedness"), 4121 G_("pointer targets in assignment " 4122 "differ in signedness"), 4123 G_("pointer targets in initialization " 4124 "differ in signedness"), 4125 G_("pointer targets in return differ " 4126 "in signedness")); 4127 } 4128 else if (TREE_CODE (ttl) == FUNCTION_TYPE 4129 && TREE_CODE (ttr) == FUNCTION_TYPE) 4130 { 4131 /* Because const and volatile on functions are restrictions 4132 that say the function will not do certain things, 4133 it is okay to use a const or volatile function 4134 where an ordinary one is wanted, but not vice-versa. */ 4135 if (TYPE_QUALS (ttl) & ~TYPE_QUALS (ttr)) 4136 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE makes " 4137 "qualified function pointer " 4138 "from unqualified"), 4139 G_("assignment makes qualified function " 4140 "pointer from unqualified"), 4141 G_("initialization makes qualified " 4142 "function pointer from unqualified"), 4143 G_("return makes qualified function " 4144 "pointer from unqualified")); 4145 } 4146 } 4147 else 4148 /* Avoid warning about the volatile ObjC EH puts on decls. */ 4149 if (!objc_ok) 4150 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE from " 4151 "incompatible pointer type"), 4152 G_("assignment from incompatible pointer type"), 4153 G_("initialization from incompatible " 4154 "pointer type"), 4155 G_("return from incompatible pointer type")); 4156 4157 return convert (type, rhs); 4158 } 4159 else if (codel == POINTER_TYPE && coder == ARRAY_TYPE) 4160 { 4161 /* ??? This should not be an error when inlining calls to 4162 unprototyped functions. */ 4163 error ("invalid use of non-lvalue array"); 4164 return error_mark_node; 4165 } 4166 else if (codel == POINTER_TYPE && coder == INTEGER_TYPE) 4167 { 4168 /* An explicit constant 0 can convert to a pointer, 4169 or one that results from arithmetic, even including 4170 a cast to integer type. */ 4171 if (!null_pointer_constant_p (rhs)) 4172 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE makes " 4173 "pointer from integer without a cast"), 4174 G_("assignment makes pointer from integer " 4175 "without a cast"), 4176 G_("initialization makes pointer from " 4177 "integer without a cast"), 4178 G_("return makes pointer from integer " 4179 "without a cast")); 4180 4181 return convert (type, rhs); 4182 } 4183 else if (codel == INTEGER_TYPE && coder == POINTER_TYPE) 4184 { 4185 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE makes integer " 4186 "from pointer without a cast"), 4187 G_("assignment makes integer from pointer " 4188 "without a cast"), 4189 G_("initialization makes integer from pointer " 4190 "without a cast"), 4191 G_("return makes integer from pointer " 4192 "without a cast")); 4193 return convert (type, rhs); 4194 } 4195 else if (codel == BOOLEAN_TYPE && coder == POINTER_TYPE) 4196 return convert (type, rhs); 4197 4198 switch (errtype) 4199 { 4200 case ic_argpass: 4201 case ic_argpass_nonproto: 4202 /* ??? This should not be an error when inlining calls to 4203 unprototyped functions. */ 4204 error ("incompatible type for argument %d of %qE", parmnum, rname); 4205 break; 4206 case ic_assign: 4207 error ("incompatible types in assignment"); 4208 break; 4209 case ic_init: 4210 error ("incompatible types in initialization"); 4211 break; 4212 case ic_return: 4213 error ("incompatible types in return"); 4214 break; 4215 default: 4216 gcc_unreachable (); 4217 } 4218 4219 return error_mark_node; 4220} 4221 4222/* Convert VALUE for assignment into inlined parameter PARM. ARGNUM 4223 is used for error and warning reporting and indicates which argument 4224 is being processed. */ 4225 4226tree 4227c_convert_parm_for_inlining (tree parm, tree value, tree fn, int argnum) 4228{ 4229 tree ret, type; 4230 4231 /* If FN was prototyped at the call site, the value has been converted 4232 already in convert_arguments. 4233 However, we might see a prototype now that was not in place when 4234 the function call was seen, so check that the VALUE actually matches 4235 PARM before taking an early exit. */ 4236 if (!value 4237 || (TYPE_ARG_TYPES (TREE_TYPE (fn)) 4238 && (TYPE_MAIN_VARIANT (TREE_TYPE (parm)) 4239 == TYPE_MAIN_VARIANT (TREE_TYPE (value))))) 4240 return value; 4241 4242 type = TREE_TYPE (parm); 4243 ret = convert_for_assignment (type, value, 4244 ic_argpass_nonproto, fn, 4245 fn, argnum); 4246 if (targetm.calls.promote_prototypes (TREE_TYPE (fn)) 4247 && INTEGRAL_TYPE_P (type) 4248 && (TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node))) 4249 ret = default_conversion (ret); 4250 return ret; 4251} 4252 4253/* If VALUE is a compound expr all of whose expressions are constant, then 4254 return its value. Otherwise, return error_mark_node. 4255 4256 This is for handling COMPOUND_EXPRs as initializer elements 4257 which is allowed with a warning when -pedantic is specified. */ 4258 4259static tree 4260valid_compound_expr_initializer (tree value, tree endtype) 4261{ 4262 if (TREE_CODE (value) == COMPOUND_EXPR) 4263 { 4264 if (valid_compound_expr_initializer (TREE_OPERAND (value, 0), endtype) 4265 == error_mark_node) 4266 return error_mark_node; 4267 return valid_compound_expr_initializer (TREE_OPERAND (value, 1), 4268 endtype); 4269 } 4270 else if (!initializer_constant_valid_p (value, endtype)) 4271 return error_mark_node; 4272 else 4273 return value; 4274} 4275 4276/* Perform appropriate conversions on the initial value of a variable, 4277 store it in the declaration DECL, 4278 and print any error messages that are appropriate. 4279 If the init is invalid, store an ERROR_MARK. */ 4280 4281void 4282store_init_value (tree decl, tree init) 4283{ 4284 tree value, type; 4285 4286 /* If variable's type was invalidly declared, just ignore it. */ 4287 4288 type = TREE_TYPE (decl); 4289 if (TREE_CODE (type) == ERROR_MARK) 4290 return; 4291 4292 /* Digest the specified initializer into an expression. */ 4293 4294 value = digest_init (type, init, true, TREE_STATIC (decl)); 4295 4296 /* Store the expression if valid; else report error. */ 4297 4298 if (!in_system_header 4299 && AGGREGATE_TYPE_P (TREE_TYPE (decl)) && !TREE_STATIC (decl)) 4300 warning (OPT_Wtraditional, "traditional C rejects automatic " 4301 "aggregate initialization"); 4302 4303 DECL_INITIAL (decl) = value; 4304 4305 /* ANSI wants warnings about out-of-range constant initializers. */ 4306 STRIP_TYPE_NOPS (value); 4307 constant_expression_warning (value); 4308 4309 /* Check if we need to set array size from compound literal size. */ 4310 if (TREE_CODE (type) == ARRAY_TYPE 4311 && TYPE_DOMAIN (type) == 0 4312 && value != error_mark_node) 4313 { 4314 tree inside_init = init; 4315 4316 STRIP_TYPE_NOPS (inside_init); 4317 inside_init = fold (inside_init); 4318 4319 if (TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR) 4320 { 4321 tree cldecl = COMPOUND_LITERAL_EXPR_DECL (inside_init); 4322 4323 if (TYPE_DOMAIN (TREE_TYPE (cldecl))) 4324 { 4325 /* For int foo[] = (int [3]){1}; we need to set array size 4326 now since later on array initializer will be just the 4327 brace enclosed list of the compound literal. */ 4328 type = build_distinct_type_copy (TYPE_MAIN_VARIANT (type)); 4329 TREE_TYPE (decl) = type; 4330 TYPE_DOMAIN (type) = TYPE_DOMAIN (TREE_TYPE (cldecl)); 4331 layout_type (type); 4332 layout_decl (cldecl, 0); 4333 } 4334 } 4335 } 4336} 4337 4338/* Methods for storing and printing names for error messages. */ 4339 4340/* Implement a spelling stack that allows components of a name to be pushed 4341 and popped. Each element on the stack is this structure. */ 4342 4343struct spelling 4344{ 4345 int kind; 4346 union 4347 { 4348 unsigned HOST_WIDE_INT i; 4349 const char *s; 4350 } u; 4351}; 4352 4353#define SPELLING_STRING 1 4354#define SPELLING_MEMBER 2 4355#define SPELLING_BOUNDS 3 4356 4357static struct spelling *spelling; /* Next stack element (unused). */ 4358static struct spelling *spelling_base; /* Spelling stack base. */ 4359static int spelling_size; /* Size of the spelling stack. */ 4360 4361/* Macros to save and restore the spelling stack around push_... functions. 4362 Alternative to SAVE_SPELLING_STACK. */ 4363 4364#define SPELLING_DEPTH() (spelling - spelling_base) 4365#define RESTORE_SPELLING_DEPTH(DEPTH) (spelling = spelling_base + (DEPTH)) 4366 4367/* Push an element on the spelling stack with type KIND and assign VALUE 4368 to MEMBER. */ 4369 4370#define PUSH_SPELLING(KIND, VALUE, MEMBER) \ 4371{ \ 4372 int depth = SPELLING_DEPTH (); \ 4373 \ 4374 if (depth >= spelling_size) \ 4375 { \ 4376 spelling_size += 10; \ 4377 spelling_base = XRESIZEVEC (struct spelling, spelling_base, \ 4378 spelling_size); \ 4379 RESTORE_SPELLING_DEPTH (depth); \ 4380 } \ 4381 \ 4382 spelling->kind = (KIND); \ 4383 spelling->MEMBER = (VALUE); \ 4384 spelling++; \ 4385} 4386 4387/* Push STRING on the stack. Printed literally. */ 4388 4389static void 4390push_string (const char *string) 4391{ 4392 PUSH_SPELLING (SPELLING_STRING, string, u.s); 4393} 4394 4395/* Push a member name on the stack. Printed as '.' STRING. */ 4396 4397static void 4398push_member_name (tree decl) 4399{ 4400 const char *const string 4401 = DECL_NAME (decl) ? IDENTIFIER_POINTER (DECL_NAME (decl)) : "<anonymous>"; 4402 PUSH_SPELLING (SPELLING_MEMBER, string, u.s); 4403} 4404 4405/* Push an array bounds on the stack. Printed as [BOUNDS]. */ 4406 4407static void 4408push_array_bounds (unsigned HOST_WIDE_INT bounds) 4409{ 4410 PUSH_SPELLING (SPELLING_BOUNDS, bounds, u.i); 4411} 4412 4413/* Compute the maximum size in bytes of the printed spelling. */ 4414 4415static int 4416spelling_length (void) 4417{ 4418 int size = 0; 4419 struct spelling *p; 4420 4421 for (p = spelling_base; p < spelling; p++) 4422 { 4423 if (p->kind == SPELLING_BOUNDS) 4424 size += 25; 4425 else 4426 size += strlen (p->u.s) + 1; 4427 } 4428 4429 return size; 4430} 4431 4432/* Print the spelling to BUFFER and return it. */ 4433 4434static char * 4435print_spelling (char *buffer) 4436{ 4437 char *d = buffer; 4438 struct spelling *p; 4439 4440 for (p = spelling_base; p < spelling; p++) 4441 if (p->kind == SPELLING_BOUNDS) 4442 { 4443 sprintf (d, "[" HOST_WIDE_INT_PRINT_UNSIGNED "]", p->u.i); 4444 d += strlen (d); 4445 } 4446 else 4447 { 4448 const char *s; 4449 if (p->kind == SPELLING_MEMBER) 4450 *d++ = '.'; 4451 for (s = p->u.s; (*d = *s++); d++) 4452 ; 4453 } 4454 *d++ = '\0'; 4455 return buffer; 4456} 4457 4458/* Issue an error message for a bad initializer component. 4459 MSGID identifies the message. 4460 The component name is taken from the spelling stack. */ 4461 4462void 4463error_init (const char *msgid) 4464{ 4465 char *ofwhat; 4466 4467 error ("%s", _(msgid)); 4468 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1)); 4469 if (*ofwhat) 4470 error ("(near initialization for %qs)", ofwhat); 4471} 4472 4473/* Issue a pedantic warning for a bad initializer component. 4474 MSGID identifies the message. 4475 The component name is taken from the spelling stack. */ 4476 4477void 4478pedwarn_init (const char *msgid) 4479{ 4480 char *ofwhat; 4481 4482 pedwarn ("%s", _(msgid)); 4483 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1)); 4484 if (*ofwhat) 4485 pedwarn ("(near initialization for %qs)", ofwhat); 4486} 4487 4488/* Issue a warning for a bad initializer component. 4489 MSGID identifies the message. 4490 The component name is taken from the spelling stack. */ 4491 4492static void 4493warning_init (const char *msgid) 4494{ 4495 char *ofwhat; 4496 4497 warning (0, "%s", _(msgid)); 4498 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1)); 4499 if (*ofwhat) 4500 warning (0, "(near initialization for %qs)", ofwhat); 4501} 4502 4503/* If TYPE is an array type and EXPR is a parenthesized string 4504 constant, warn if pedantic that EXPR is being used to initialize an 4505 object of type TYPE. */ 4506 4507void 4508maybe_warn_string_init (tree type, struct c_expr expr) 4509{ 4510 if (pedantic 4511 && TREE_CODE (type) == ARRAY_TYPE 4512 && TREE_CODE (expr.value) == STRING_CST 4513 && expr.original_code != STRING_CST) 4514 pedwarn_init ("array initialized from parenthesized string constant"); 4515} 4516 4517/* Digest the parser output INIT as an initializer for type TYPE. 4518 Return a C expression of type TYPE to represent the initial value. 4519 4520 If INIT is a string constant, STRICT_STRING is true if it is 4521 unparenthesized or we should not warn here for it being parenthesized. 4522 For other types of INIT, STRICT_STRING is not used. 4523 4524 REQUIRE_CONSTANT requests an error if non-constant initializers or 4525 elements are seen. */ 4526 4527static tree 4528digest_init (tree type, tree init, bool strict_string, int require_constant) 4529{ 4530 enum tree_code code = TREE_CODE (type); 4531 tree inside_init = init; 4532 4533 if (type == error_mark_node 4534 || !init 4535 || init == error_mark_node 4536 || TREE_TYPE (init) == error_mark_node) 4537 return error_mark_node; 4538 4539 STRIP_TYPE_NOPS (inside_init); 4540 4541 inside_init = fold (inside_init); 4542 4543 /* Initialization of an array of chars from a string constant 4544 optionally enclosed in braces. */ 4545 4546 if (code == ARRAY_TYPE && inside_init 4547 && TREE_CODE (inside_init) == STRING_CST) 4548 { 4549 tree typ1 = TYPE_MAIN_VARIANT (TREE_TYPE (type)); 4550 /* Note that an array could be both an array of character type 4551 and an array of wchar_t if wchar_t is signed char or unsigned 4552 char. */ 4553 bool char_array = (typ1 == char_type_node 4554 || typ1 == signed_char_type_node 4555 || typ1 == unsigned_char_type_node); 4556 bool wchar_array = !!comptypes (typ1, wchar_type_node); 4557 if (char_array || wchar_array) 4558 { 4559 struct c_expr expr; 4560 bool char_string; 4561 expr.value = inside_init; 4562 expr.original_code = (strict_string ? STRING_CST : ERROR_MARK); 4563 maybe_warn_string_init (type, expr); 4564 4565 char_string 4566 = (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (inside_init))) 4567 == char_type_node); 4568 4569 if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)), 4570 TYPE_MAIN_VARIANT (type))) 4571 return inside_init; 4572 4573 if (!wchar_array && !char_string) 4574 { 4575 error_init ("char-array initialized from wide string"); 4576 return error_mark_node; 4577 } 4578 if (char_string && !char_array) 4579 { 4580 error_init ("wchar_t-array initialized from non-wide string"); 4581 return error_mark_node; 4582 } 4583 4584 TREE_TYPE (inside_init) = type; 4585 if (TYPE_DOMAIN (type) != 0 4586 && TYPE_SIZE (type) != 0 4587 && TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST 4588 /* Subtract 1 (or sizeof (wchar_t)) 4589 because it's ok to ignore the terminating null char 4590 that is counted in the length of the constant. */ 4591 && 0 > compare_tree_int (TYPE_SIZE_UNIT (type), 4592 TREE_STRING_LENGTH (inside_init) 4593 - ((TYPE_PRECISION (typ1) 4594 != TYPE_PRECISION (char_type_node)) 4595 ? (TYPE_PRECISION (wchar_type_node) 4596 / BITS_PER_UNIT) 4597 : 1))) 4598 pedwarn_init ("initializer-string for array of chars is too long"); 4599 4600 return inside_init; 4601 } 4602 else if (INTEGRAL_TYPE_P (typ1)) 4603 { 4604 error_init ("array of inappropriate type initialized " 4605 "from string constant"); 4606 return error_mark_node; 4607 } 4608 } 4609 4610 /* Build a VECTOR_CST from a *constant* vector constructor. If the 4611 vector constructor is not constant (e.g. {1,2,3,foo()}) then punt 4612 below and handle as a constructor. */ 4613 if (code == VECTOR_TYPE 4614 && TREE_CODE (TREE_TYPE (inside_init)) == VECTOR_TYPE 4615 && vector_types_convertible_p (TREE_TYPE (inside_init), type) 4616 && TREE_CONSTANT (inside_init)) 4617 { 4618 if (TREE_CODE (inside_init) == VECTOR_CST 4619 && comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)), 4620 TYPE_MAIN_VARIANT (type))) 4621 return inside_init; 4622 4623 if (TREE_CODE (inside_init) == CONSTRUCTOR) 4624 { 4625 unsigned HOST_WIDE_INT ix; 4626 tree value; 4627 bool constant_p = true; 4628 4629 /* Iterate through elements and check if all constructor 4630 elements are *_CSTs. */ 4631 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (inside_init), ix, value) 4632 if (!CONSTANT_CLASS_P (value)) 4633 { 4634 constant_p = false; 4635 break; 4636 } 4637 4638 if (constant_p) 4639 return build_vector_from_ctor (type, 4640 CONSTRUCTOR_ELTS (inside_init)); 4641 } 4642 } 4643 4644 /* Any type can be initialized 4645 from an expression of the same type, optionally with braces. */ 4646 4647 if (inside_init && TREE_TYPE (inside_init) != 0 4648 && (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)), 4649 TYPE_MAIN_VARIANT (type)) 4650 || (code == ARRAY_TYPE 4651 && comptypes (TREE_TYPE (inside_init), type)) 4652 || (code == VECTOR_TYPE 4653 && comptypes (TREE_TYPE (inside_init), type)) 4654 || (code == POINTER_TYPE 4655 && TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE 4656 && comptypes (TREE_TYPE (TREE_TYPE (inside_init)), 4657 TREE_TYPE (type))))) 4658 { 4659 if (code == POINTER_TYPE) 4660 { 4661 if (TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE) 4662 { 4663 if (TREE_CODE (inside_init) == STRING_CST 4664 || TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR) 4665 inside_init = array_to_pointer_conversion (inside_init); 4666 else 4667 { 4668 error_init ("invalid use of non-lvalue array"); 4669 return error_mark_node; 4670 } 4671 } 4672 } 4673 4674 if (code == VECTOR_TYPE) 4675 /* Although the types are compatible, we may require a 4676 conversion. */ 4677 inside_init = convert (type, inside_init); 4678 4679 if (require_constant 4680 && (code == VECTOR_TYPE || !flag_isoc99) 4681 && TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR) 4682 { 4683 /* As an extension, allow initializing objects with static storage 4684 duration with compound literals (which are then treated just as 4685 the brace enclosed list they contain). Also allow this for 4686 vectors, as we can only assign them with compound literals. */ 4687 tree decl = COMPOUND_LITERAL_EXPR_DECL (inside_init); 4688 inside_init = DECL_INITIAL (decl); 4689 } 4690 4691 if (code == ARRAY_TYPE && TREE_CODE (inside_init) != STRING_CST 4692 && TREE_CODE (inside_init) != CONSTRUCTOR) 4693 { 4694 error_init ("array initialized from non-constant array expression"); 4695 return error_mark_node; 4696 } 4697 4698 if (optimize && TREE_CODE (inside_init) == VAR_DECL) 4699 inside_init = decl_constant_value_for_broken_optimization (inside_init); 4700 4701 /* Compound expressions can only occur here if -pedantic or 4702 -pedantic-errors is specified. In the later case, we always want 4703 an error. In the former case, we simply want a warning. */ 4704 if (require_constant && pedantic 4705 && TREE_CODE (inside_init) == COMPOUND_EXPR) 4706 { 4707 inside_init 4708 = valid_compound_expr_initializer (inside_init, 4709 TREE_TYPE (inside_init)); 4710 if (inside_init == error_mark_node) 4711 error_init ("initializer element is not constant"); 4712 else 4713 pedwarn_init ("initializer element is not constant"); 4714 if (flag_pedantic_errors) 4715 inside_init = error_mark_node; 4716 } 4717 else if (require_constant 4718 && !initializer_constant_valid_p (inside_init, 4719 TREE_TYPE (inside_init))) 4720 { 4721 error_init ("initializer element is not constant"); 4722 inside_init = error_mark_node; 4723 } 4724 4725 /* Added to enable additional -Wmissing-format-attribute warnings. */ 4726 if (TREE_CODE (TREE_TYPE (inside_init)) == POINTER_TYPE) 4727 inside_init = convert_for_assignment (type, inside_init, ic_init, NULL_TREE, 4728 NULL_TREE, 0); 4729 return inside_init; 4730 } 4731 4732 /* Handle scalar types, including conversions. */ 4733 4734 if (code == INTEGER_TYPE || code == REAL_TYPE || code == POINTER_TYPE 4735 || code == ENUMERAL_TYPE || code == BOOLEAN_TYPE || code == COMPLEX_TYPE 4736 || code == VECTOR_TYPE) 4737 { 4738 if (TREE_CODE (TREE_TYPE (init)) == ARRAY_TYPE 4739 && (TREE_CODE (init) == STRING_CST 4740 || TREE_CODE (init) == COMPOUND_LITERAL_EXPR)) 4741 init = array_to_pointer_conversion (init); 4742 inside_init 4743 = convert_for_assignment (type, init, ic_init, 4744 NULL_TREE, NULL_TREE, 0); 4745 4746 /* Check to see if we have already given an error message. */ 4747 if (inside_init == error_mark_node) 4748 ; 4749 else if (require_constant && !TREE_CONSTANT (inside_init)) 4750 { 4751 error_init ("initializer element is not constant"); 4752 inside_init = error_mark_node; 4753 } 4754 else if (require_constant 4755 && !initializer_constant_valid_p (inside_init, 4756 TREE_TYPE (inside_init))) 4757 { 4758 error_init ("initializer element is not computable at load time"); 4759 inside_init = error_mark_node; 4760 } 4761 4762 return inside_init; 4763 } 4764 4765 /* Come here only for records and arrays. */ 4766 4767 if (COMPLETE_TYPE_P (type) && TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST) 4768 { 4769 error_init ("variable-sized object may not be initialized"); 4770 return error_mark_node; 4771 } 4772 4773 error_init ("invalid initializer"); 4774 return error_mark_node; 4775} 4776 4777/* Handle initializers that use braces. */ 4778 4779/* Type of object we are accumulating a constructor for. 4780 This type is always a RECORD_TYPE, UNION_TYPE or ARRAY_TYPE. */ 4781static tree constructor_type; 4782 4783/* For a RECORD_TYPE or UNION_TYPE, this is the chain of fields 4784 left to fill. */ 4785static tree constructor_fields; 4786 4787/* For an ARRAY_TYPE, this is the specified index 4788 at which to store the next element we get. */ 4789static tree constructor_index; 4790 4791/* For an ARRAY_TYPE, this is the maximum index. */ 4792static tree constructor_max_index; 4793 4794/* For a RECORD_TYPE, this is the first field not yet written out. */ 4795static tree constructor_unfilled_fields; 4796 4797/* For an ARRAY_TYPE, this is the index of the first element 4798 not yet written out. */ 4799static tree constructor_unfilled_index; 4800 4801/* In a RECORD_TYPE, the byte index of the next consecutive field. 4802 This is so we can generate gaps between fields, when appropriate. */ 4803static tree constructor_bit_index; 4804 4805/* If we are saving up the elements rather than allocating them, 4806 this is the list of elements so far (in reverse order, 4807 most recent first). */ 4808static VEC(constructor_elt,gc) *constructor_elements; 4809 4810/* 1 if constructor should be incrementally stored into a constructor chain, 4811 0 if all the elements should be kept in AVL tree. */ 4812static int constructor_incremental; 4813 4814/* 1 if so far this constructor's elements are all compile-time constants. */ 4815static int constructor_constant; 4816 4817/* 1 if so far this constructor's elements are all valid address constants. */ 4818static int constructor_simple; 4819 4820/* 1 if this constructor is erroneous so far. */ 4821static int constructor_erroneous; 4822 4823/* Structure for managing pending initializer elements, organized as an 4824 AVL tree. */ 4825 4826struct init_node 4827{ 4828 struct init_node *left, *right; 4829 struct init_node *parent; 4830 int balance; 4831 tree purpose; 4832 tree value; 4833}; 4834 4835/* Tree of pending elements at this constructor level. 4836 These are elements encountered out of order 4837 which belong at places we haven't reached yet in actually 4838 writing the output. 4839 Will never hold tree nodes across GC runs. */ 4840static struct init_node *constructor_pending_elts; 4841 4842/* The SPELLING_DEPTH of this constructor. */ 4843static int constructor_depth; 4844 4845/* DECL node for which an initializer is being read. 4846 0 means we are reading a constructor expression 4847 such as (struct foo) {...}. */ 4848static tree constructor_decl; 4849 4850/* Nonzero if this is an initializer for a top-level decl. */ 4851static int constructor_top_level; 4852 4853/* Nonzero if there were any member designators in this initializer. */ 4854static int constructor_designated; 4855 4856/* Nesting depth of designator list. */ 4857static int designator_depth; 4858 4859/* Nonzero if there were diagnosed errors in this designator list. */ 4860static int designator_erroneous; 4861 4862 4863/* This stack has a level for each implicit or explicit level of 4864 structuring in the initializer, including the outermost one. It 4865 saves the values of most of the variables above. */ 4866 4867struct constructor_range_stack; 4868 4869struct constructor_stack 4870{ 4871 struct constructor_stack *next; 4872 tree type; 4873 tree fields; 4874 tree index; 4875 tree max_index; 4876 tree unfilled_index; 4877 tree unfilled_fields; 4878 tree bit_index; 4879 VEC(constructor_elt,gc) *elements; 4880 struct init_node *pending_elts; 4881 int offset; 4882 int depth; 4883 /* If value nonzero, this value should replace the entire 4884 constructor at this level. */ 4885 struct c_expr replacement_value; 4886 struct constructor_range_stack *range_stack; 4887 char constant; 4888 char simple; 4889 char implicit; 4890 char erroneous; 4891 char outer; 4892 char incremental; 4893 char designated; 4894}; 4895 4896static struct constructor_stack *constructor_stack; 4897 4898/* This stack represents designators from some range designator up to 4899 the last designator in the list. */ 4900 4901struct constructor_range_stack 4902{ 4903 struct constructor_range_stack *next, *prev; 4904 struct constructor_stack *stack; 4905 tree range_start; 4906 tree index; 4907 tree range_end; 4908 tree fields; 4909}; 4910 4911static struct constructor_range_stack *constructor_range_stack; 4912 4913/* This stack records separate initializers that are nested. 4914 Nested initializers can't happen in ANSI C, but GNU C allows them 4915 in cases like { ... (struct foo) { ... } ... }. */ 4916 4917struct initializer_stack 4918{ 4919 struct initializer_stack *next; 4920 tree decl; 4921 struct constructor_stack *constructor_stack; 4922 struct constructor_range_stack *constructor_range_stack; 4923 VEC(constructor_elt,gc) *elements; 4924 struct spelling *spelling; 4925 struct spelling *spelling_base; 4926 int spelling_size; 4927 char top_level; 4928 char require_constant_value; 4929 char require_constant_elements; 4930}; 4931 4932static struct initializer_stack *initializer_stack; 4933 4934/* Prepare to parse and output the initializer for variable DECL. */ 4935 4936void 4937start_init (tree decl, tree asmspec_tree ATTRIBUTE_UNUSED, int top_level) 4938{ 4939 const char *locus; 4940 struct initializer_stack *p = XNEW (struct initializer_stack); 4941 4942 p->decl = constructor_decl; 4943 p->require_constant_value = require_constant_value; 4944 p->require_constant_elements = require_constant_elements; 4945 p->constructor_stack = constructor_stack; 4946 p->constructor_range_stack = constructor_range_stack; 4947 p->elements = constructor_elements; 4948 p->spelling = spelling; 4949 p->spelling_base = spelling_base; 4950 p->spelling_size = spelling_size; 4951 p->top_level = constructor_top_level; 4952 p->next = initializer_stack; 4953 initializer_stack = p; 4954 4955 constructor_decl = decl; 4956 constructor_designated = 0; 4957 constructor_top_level = top_level; 4958 4959 if (decl != 0 && decl != error_mark_node) 4960 { 4961 require_constant_value = TREE_STATIC (decl); 4962 require_constant_elements 4963 = ((TREE_STATIC (decl) || (pedantic && !flag_isoc99)) 4964 /* For a scalar, you can always use any value to initialize, 4965 even within braces. */ 4966 && (TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE 4967 || TREE_CODE (TREE_TYPE (decl)) == RECORD_TYPE 4968 || TREE_CODE (TREE_TYPE (decl)) == UNION_TYPE 4969 || TREE_CODE (TREE_TYPE (decl)) == QUAL_UNION_TYPE)); 4970 locus = IDENTIFIER_POINTER (DECL_NAME (decl)); 4971 } 4972 else 4973 { 4974 require_constant_value = 0; 4975 require_constant_elements = 0; 4976 locus = "(anonymous)"; 4977 } 4978 4979 constructor_stack = 0; 4980 constructor_range_stack = 0; 4981 4982 missing_braces_mentioned = 0; 4983 4984 spelling_base = 0; 4985 spelling_size = 0; 4986 RESTORE_SPELLING_DEPTH (0); 4987 4988 if (locus) 4989 push_string (locus); 4990} 4991 4992void 4993finish_init (void) 4994{ 4995 struct initializer_stack *p = initializer_stack; 4996 4997 /* Free the whole constructor stack of this initializer. */ 4998 while (constructor_stack) 4999 { 5000 struct constructor_stack *q = constructor_stack; 5001 constructor_stack = q->next; 5002 free (q); 5003 } 5004 5005 gcc_assert (!constructor_range_stack); 5006 5007 /* Pop back to the data of the outer initializer (if any). */ 5008 free (spelling_base); 5009 5010 constructor_decl = p->decl; 5011 require_constant_value = p->require_constant_value; 5012 require_constant_elements = p->require_constant_elements; 5013 constructor_stack = p->constructor_stack; 5014 constructor_range_stack = p->constructor_range_stack; 5015 constructor_elements = p->elements; 5016 spelling = p->spelling; 5017 spelling_base = p->spelling_base; 5018 spelling_size = p->spelling_size; 5019 constructor_top_level = p->top_level; 5020 initializer_stack = p->next; 5021 free (p); 5022} 5023 5024/* Call here when we see the initializer is surrounded by braces. 5025 This is instead of a call to push_init_level; 5026 it is matched by a call to pop_init_level. 5027 5028 TYPE is the type to initialize, for a constructor expression. 5029 For an initializer for a decl, TYPE is zero. */ 5030 5031void 5032really_start_incremental_init (tree type) 5033{ 5034 struct constructor_stack *p = XNEW (struct constructor_stack); 5035 5036 if (type == 0) 5037 type = TREE_TYPE (constructor_decl); 5038 5039 if (targetm.vector_opaque_p (type)) 5040 error ("opaque vector types cannot be initialized"); 5041 5042 p->type = constructor_type; 5043 p->fields = constructor_fields; 5044 p->index = constructor_index; 5045 p->max_index = constructor_max_index; 5046 p->unfilled_index = constructor_unfilled_index; 5047 p->unfilled_fields = constructor_unfilled_fields; 5048 p->bit_index = constructor_bit_index; 5049 p->elements = constructor_elements; 5050 p->constant = constructor_constant; 5051 p->simple = constructor_simple; 5052 p->erroneous = constructor_erroneous; 5053 p->pending_elts = constructor_pending_elts; 5054 p->depth = constructor_depth; 5055 p->replacement_value.value = 0; 5056 p->replacement_value.original_code = ERROR_MARK; 5057 p->implicit = 0; 5058 p->range_stack = 0; 5059 p->outer = 0; 5060 p->incremental = constructor_incremental; 5061 p->designated = constructor_designated; 5062 p->next = 0; 5063 constructor_stack = p; 5064 5065 constructor_constant = 1; 5066 constructor_simple = 1; 5067 constructor_depth = SPELLING_DEPTH (); 5068 constructor_elements = 0; 5069 constructor_pending_elts = 0; 5070 constructor_type = type; 5071 constructor_incremental = 1; 5072 constructor_designated = 0; 5073 designator_depth = 0; 5074 designator_erroneous = 0; 5075 5076 if (TREE_CODE (constructor_type) == RECORD_TYPE 5077 || TREE_CODE (constructor_type) == UNION_TYPE) 5078 { 5079 constructor_fields = TYPE_FIELDS (constructor_type); 5080 /* Skip any nameless bit fields at the beginning. */ 5081 while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields) 5082 && DECL_NAME (constructor_fields) == 0) 5083 constructor_fields = TREE_CHAIN (constructor_fields); 5084 5085 constructor_unfilled_fields = constructor_fields; 5086 constructor_bit_index = bitsize_zero_node; 5087 } 5088 else if (TREE_CODE (constructor_type) == ARRAY_TYPE) 5089 { 5090 if (TYPE_DOMAIN (constructor_type)) 5091 { 5092 constructor_max_index 5093 = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type)); 5094 5095 /* Detect non-empty initializations of zero-length arrays. */ 5096 if (constructor_max_index == NULL_TREE 5097 && TYPE_SIZE (constructor_type)) 5098 constructor_max_index = build_int_cst (NULL_TREE, -1); 5099 5100 /* constructor_max_index needs to be an INTEGER_CST. Attempts 5101 to initialize VLAs will cause a proper error; avoid tree 5102 checking errors as well by setting a safe value. */ 5103 if (constructor_max_index 5104 && TREE_CODE (constructor_max_index) != INTEGER_CST) 5105 constructor_max_index = build_int_cst (NULL_TREE, -1); 5106 5107 constructor_index 5108 = convert (bitsizetype, 5109 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type))); 5110 } 5111 else 5112 { 5113 constructor_index = bitsize_zero_node; 5114 constructor_max_index = NULL_TREE; 5115 } 5116 5117 constructor_unfilled_index = constructor_index; 5118 } 5119 else if (TREE_CODE (constructor_type) == VECTOR_TYPE) 5120 { 5121 /* Vectors are like simple fixed-size arrays. */ 5122 constructor_max_index = 5123 build_int_cst (NULL_TREE, TYPE_VECTOR_SUBPARTS (constructor_type) - 1); 5124 constructor_index = bitsize_zero_node; 5125 constructor_unfilled_index = constructor_index; 5126 } 5127 else 5128 { 5129 /* Handle the case of int x = {5}; */ 5130 constructor_fields = constructor_type; 5131 constructor_unfilled_fields = constructor_type; 5132 } 5133} 5134 5135/* Push down into a subobject, for initialization. 5136 If this is for an explicit set of braces, IMPLICIT is 0. 5137 If it is because the next element belongs at a lower level, 5138 IMPLICIT is 1 (or 2 if the push is because of designator list). */ 5139 5140void 5141push_init_level (int implicit) 5142{ 5143 struct constructor_stack *p; 5144 tree value = NULL_TREE; 5145 5146 /* If we've exhausted any levels that didn't have braces, 5147 pop them now. If implicit == 1, this will have been done in 5148 process_init_element; do not repeat it here because in the case 5149 of excess initializers for an empty aggregate this leads to an 5150 infinite cycle of popping a level and immediately recreating 5151 it. */ 5152 if (implicit != 1) 5153 { 5154 while (constructor_stack->implicit) 5155 { 5156 if ((TREE_CODE (constructor_type) == RECORD_TYPE 5157 || TREE_CODE (constructor_type) == UNION_TYPE) 5158 && constructor_fields == 0) 5159 process_init_element (pop_init_level (1)); 5160 else if (TREE_CODE (constructor_type) == ARRAY_TYPE 5161 && constructor_max_index 5162 && tree_int_cst_lt (constructor_max_index, 5163 constructor_index)) 5164 process_init_element (pop_init_level (1)); 5165 else 5166 break; 5167 } 5168 } 5169 5170 /* Unless this is an explicit brace, we need to preserve previous 5171 content if any. */ 5172 if (implicit) 5173 { 5174 if ((TREE_CODE (constructor_type) == RECORD_TYPE 5175 || TREE_CODE (constructor_type) == UNION_TYPE) 5176 && constructor_fields) 5177 value = find_init_member (constructor_fields); 5178 else if (TREE_CODE (constructor_type) == ARRAY_TYPE) 5179 value = find_init_member (constructor_index); 5180 } 5181 5182 p = XNEW (struct constructor_stack); 5183 p->type = constructor_type; 5184 p->fields = constructor_fields; 5185 p->index = constructor_index; 5186 p->max_index = constructor_max_index; 5187 p->unfilled_index = constructor_unfilled_index; 5188 p->unfilled_fields = constructor_unfilled_fields; 5189 p->bit_index = constructor_bit_index; 5190 p->elements = constructor_elements; 5191 p->constant = constructor_constant; 5192 p->simple = constructor_simple; 5193 p->erroneous = constructor_erroneous; 5194 p->pending_elts = constructor_pending_elts; 5195 p->depth = constructor_depth; 5196 p->replacement_value.value = 0; 5197 p->replacement_value.original_code = ERROR_MARK; 5198 p->implicit = implicit; 5199 p->outer = 0; 5200 p->incremental = constructor_incremental; 5201 p->designated = constructor_designated; 5202 p->next = constructor_stack; 5203 p->range_stack = 0; 5204 constructor_stack = p; 5205 5206 constructor_constant = 1; 5207 constructor_simple = 1; 5208 constructor_depth = SPELLING_DEPTH (); 5209 constructor_elements = 0; 5210 constructor_incremental = 1; 5211 constructor_designated = 0; 5212 constructor_pending_elts = 0; 5213 if (!implicit) 5214 { 5215 p->range_stack = constructor_range_stack; 5216 constructor_range_stack = 0; 5217 designator_depth = 0; 5218 designator_erroneous = 0; 5219 } 5220 5221 /* Don't die if an entire brace-pair level is superfluous 5222 in the containing level. */ 5223 if (constructor_type == 0) 5224 ; 5225 else if (TREE_CODE (constructor_type) == RECORD_TYPE 5226 || TREE_CODE (constructor_type) == UNION_TYPE) 5227 { 5228 /* Don't die if there are extra init elts at the end. */ 5229 if (constructor_fields == 0) 5230 constructor_type = 0; 5231 else 5232 { 5233 constructor_type = TREE_TYPE (constructor_fields); 5234 push_member_name (constructor_fields); 5235 constructor_depth++; 5236 } 5237 } 5238 else if (TREE_CODE (constructor_type) == ARRAY_TYPE) 5239 { 5240 constructor_type = TREE_TYPE (constructor_type); 5241 push_array_bounds (tree_low_cst (constructor_index, 1)); 5242 constructor_depth++; 5243 } 5244 5245 if (constructor_type == 0) 5246 { 5247 error_init ("extra brace group at end of initializer"); 5248 constructor_fields = 0; 5249 constructor_unfilled_fields = 0; 5250 return; 5251 } 5252 5253 if (value && TREE_CODE (value) == CONSTRUCTOR) 5254 { 5255 constructor_constant = TREE_CONSTANT (value); 5256 constructor_simple = TREE_STATIC (value); 5257 constructor_elements = CONSTRUCTOR_ELTS (value); 5258 if (!VEC_empty (constructor_elt, constructor_elements) 5259 && (TREE_CODE (constructor_type) == RECORD_TYPE 5260 || TREE_CODE (constructor_type) == ARRAY_TYPE)) 5261 set_nonincremental_init (); 5262 } 5263 5264 if (implicit == 1 && warn_missing_braces && !missing_braces_mentioned) 5265 { 5266 missing_braces_mentioned = 1; 5267 warning_init ("missing braces around initializer"); 5268 } 5269 5270 if (TREE_CODE (constructor_type) == RECORD_TYPE 5271 || TREE_CODE (constructor_type) == UNION_TYPE) 5272 { 5273 constructor_fields = TYPE_FIELDS (constructor_type); 5274 /* Skip any nameless bit fields at the beginning. */ 5275 while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields) 5276 && DECL_NAME (constructor_fields) == 0) 5277 constructor_fields = TREE_CHAIN (constructor_fields); 5278 5279 constructor_unfilled_fields = constructor_fields; 5280 constructor_bit_index = bitsize_zero_node; 5281 } 5282 else if (TREE_CODE (constructor_type) == VECTOR_TYPE) 5283 { 5284 /* Vectors are like simple fixed-size arrays. */ 5285 constructor_max_index = 5286 build_int_cst (NULL_TREE, TYPE_VECTOR_SUBPARTS (constructor_type) - 1); 5287 constructor_index = convert (bitsizetype, integer_zero_node); 5288 constructor_unfilled_index = constructor_index; 5289 } 5290 else if (TREE_CODE (constructor_type) == ARRAY_TYPE) 5291 { 5292 if (TYPE_DOMAIN (constructor_type)) 5293 { 5294 constructor_max_index 5295 = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type)); 5296 5297 /* Detect non-empty initializations of zero-length arrays. */ 5298 if (constructor_max_index == NULL_TREE 5299 && TYPE_SIZE (constructor_type)) 5300 constructor_max_index = build_int_cst (NULL_TREE, -1); 5301 5302 /* constructor_max_index needs to be an INTEGER_CST. Attempts 5303 to initialize VLAs will cause a proper error; avoid tree 5304 checking errors as well by setting a safe value. */ 5305 if (constructor_max_index 5306 && TREE_CODE (constructor_max_index) != INTEGER_CST) 5307 constructor_max_index = build_int_cst (NULL_TREE, -1); 5308 5309 constructor_index 5310 = convert (bitsizetype, 5311 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type))); 5312 } 5313 else 5314 constructor_index = bitsize_zero_node; 5315 5316 constructor_unfilled_index = constructor_index; 5317 if (value && TREE_CODE (value) == STRING_CST) 5318 { 5319 /* We need to split the char/wchar array into individual 5320 characters, so that we don't have to special case it 5321 everywhere. */ 5322 set_nonincremental_init_from_string (value); 5323 } 5324 } 5325 else 5326 { 5327 if (constructor_type != error_mark_node) 5328 warning_init ("braces around scalar initializer"); 5329 constructor_fields = constructor_type; 5330 constructor_unfilled_fields = constructor_type; 5331 } 5332} 5333 5334/* At the end of an implicit or explicit brace level, 5335 finish up that level of constructor. If a single expression 5336 with redundant braces initialized that level, return the 5337 c_expr structure for that expression. Otherwise, the original_code 5338 element is set to ERROR_MARK. 5339 If we were outputting the elements as they are read, return 0 as the value 5340 from inner levels (process_init_element ignores that), 5341 but return error_mark_node as the value from the outermost level 5342 (that's what we want to put in DECL_INITIAL). 5343 Otherwise, return a CONSTRUCTOR expression as the value. */ 5344 5345struct c_expr 5346pop_init_level (int implicit) 5347{ 5348 struct constructor_stack *p; 5349 struct c_expr ret; 5350 ret.value = 0; 5351 ret.original_code = ERROR_MARK; 5352 5353 if (implicit == 0) 5354 { 5355 /* When we come to an explicit close brace, 5356 pop any inner levels that didn't have explicit braces. */ 5357 while (constructor_stack->implicit) 5358 process_init_element (pop_init_level (1)); 5359 5360 gcc_assert (!constructor_range_stack); 5361 } 5362 5363 /* Now output all pending elements. */ 5364 constructor_incremental = 1; 5365 output_pending_init_elements (1); 5366 5367 p = constructor_stack; 5368 5369 /* Error for initializing a flexible array member, or a zero-length 5370 array member in an inappropriate context. */ 5371 if (constructor_type && constructor_fields 5372 && TREE_CODE (constructor_type) == ARRAY_TYPE 5373 && TYPE_DOMAIN (constructor_type) 5374 && !TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type))) 5375 { 5376 /* Silently discard empty initializations. The parser will 5377 already have pedwarned for empty brackets. */ 5378 if (integer_zerop (constructor_unfilled_index)) 5379 constructor_type = NULL_TREE; 5380 else 5381 { 5382 gcc_assert (!TYPE_SIZE (constructor_type)); 5383 5384 if (constructor_depth > 2) 5385 error_init ("initialization of flexible array member in a nested context"); 5386 else if (pedantic) 5387 pedwarn_init ("initialization of a flexible array member"); 5388 5389 /* We have already issued an error message for the existence 5390 of a flexible array member not at the end of the structure. 5391 Discard the initializer so that we do not die later. */ 5392 if (TREE_CHAIN (constructor_fields) != NULL_TREE) 5393 constructor_type = NULL_TREE; 5394 } 5395 } 5396 5397 /* Warn when some struct elements are implicitly initialized to zero. */ 5398 if (warn_missing_field_initializers 5399 && constructor_type 5400 && TREE_CODE (constructor_type) == RECORD_TYPE 5401 && constructor_unfilled_fields) 5402 { 5403 /* Do not warn for flexible array members or zero-length arrays. */ 5404 while (constructor_unfilled_fields 5405 && (!DECL_SIZE (constructor_unfilled_fields) 5406 || integer_zerop (DECL_SIZE (constructor_unfilled_fields)))) 5407 constructor_unfilled_fields = TREE_CHAIN (constructor_unfilled_fields); 5408 5409 /* Do not warn if this level of the initializer uses member 5410 designators; it is likely to be deliberate. */ 5411 if (constructor_unfilled_fields && !constructor_designated) 5412 { 5413 push_member_name (constructor_unfilled_fields); 5414 warning_init ("missing initializer"); 5415 RESTORE_SPELLING_DEPTH (constructor_depth); 5416 } 5417 } 5418 5419 /* Pad out the end of the structure. */ 5420 if (p->replacement_value.value) 5421 /* If this closes a superfluous brace pair, 5422 just pass out the element between them. */ 5423 ret = p->replacement_value; 5424 else if (constructor_type == 0) 5425 ; 5426 else if (TREE_CODE (constructor_type) != RECORD_TYPE 5427 && TREE_CODE (constructor_type) != UNION_TYPE 5428 && TREE_CODE (constructor_type) != ARRAY_TYPE 5429 && TREE_CODE (constructor_type) != VECTOR_TYPE) 5430 { 5431 /* A nonincremental scalar initializer--just return 5432 the element, after verifying there is just one. */ 5433 if (VEC_empty (constructor_elt,constructor_elements)) 5434 { 5435 if (!constructor_erroneous) 5436 error_init ("empty scalar initializer"); 5437 ret.value = error_mark_node; 5438 } 5439 else if (VEC_length (constructor_elt,constructor_elements) != 1) 5440 { 5441 error_init ("extra elements in scalar initializer"); 5442 ret.value = VEC_index (constructor_elt,constructor_elements,0)->value; 5443 } 5444 else 5445 ret.value = VEC_index (constructor_elt,constructor_elements,0)->value; 5446 } 5447 else 5448 { 5449 if (constructor_erroneous) 5450 ret.value = error_mark_node; 5451 else 5452 { 5453 ret.value = build_constructor (constructor_type, 5454 constructor_elements); 5455 if (constructor_constant) 5456 TREE_CONSTANT (ret.value) = TREE_INVARIANT (ret.value) = 1; 5457 if (constructor_constant && constructor_simple) 5458 TREE_STATIC (ret.value) = 1; 5459 } 5460 } 5461 5462 constructor_type = p->type; 5463 constructor_fields = p->fields; 5464 constructor_index = p->index; 5465 constructor_max_index = p->max_index; 5466 constructor_unfilled_index = p->unfilled_index; 5467 constructor_unfilled_fields = p->unfilled_fields; 5468 constructor_bit_index = p->bit_index; 5469 constructor_elements = p->elements; 5470 constructor_constant = p->constant; 5471 constructor_simple = p->simple; 5472 constructor_erroneous = p->erroneous; 5473 constructor_incremental = p->incremental; 5474 constructor_designated = p->designated; 5475 constructor_pending_elts = p->pending_elts; 5476 constructor_depth = p->depth; 5477 if (!p->implicit) 5478 constructor_range_stack = p->range_stack; 5479 RESTORE_SPELLING_DEPTH (constructor_depth); 5480 5481 constructor_stack = p->next; 5482 free (p); 5483 5484 if (ret.value == 0 && constructor_stack == 0) 5485 ret.value = error_mark_node; 5486 return ret; 5487} 5488 5489/* Common handling for both array range and field name designators. 5490 ARRAY argument is nonzero for array ranges. Returns zero for success. */ 5491 5492static int 5493set_designator (int array) 5494{ 5495 tree subtype; 5496 enum tree_code subcode; 5497 5498 /* Don't die if an entire brace-pair level is superfluous 5499 in the containing level. */ 5500 if (constructor_type == 0) 5501 return 1; 5502 5503 /* If there were errors in this designator list already, bail out 5504 silently. */ 5505 if (designator_erroneous) 5506 return 1; 5507 5508 if (!designator_depth) 5509 { 5510 gcc_assert (!constructor_range_stack); 5511 5512 /* Designator list starts at the level of closest explicit 5513 braces. */ 5514 while (constructor_stack->implicit) 5515 process_init_element (pop_init_level (1)); 5516 constructor_designated = 1; 5517 return 0; 5518 } 5519 5520 switch (TREE_CODE (constructor_type)) 5521 { 5522 case RECORD_TYPE: 5523 case UNION_TYPE: 5524 subtype = TREE_TYPE (constructor_fields); 5525 if (subtype != error_mark_node) 5526 subtype = TYPE_MAIN_VARIANT (subtype); 5527 break; 5528 case ARRAY_TYPE: 5529 subtype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type)); 5530 break; 5531 default: 5532 gcc_unreachable (); 5533 } 5534 5535 subcode = TREE_CODE (subtype); 5536 if (array && subcode != ARRAY_TYPE) 5537 { 5538 error_init ("array index in non-array initializer"); 5539 return 1; 5540 } 5541 else if (!array && subcode != RECORD_TYPE && subcode != UNION_TYPE) 5542 { 5543 error_init ("field name not in record or union initializer"); 5544 return 1; 5545 } 5546 5547 constructor_designated = 1; 5548 push_init_level (2); 5549 return 0; 5550} 5551 5552/* If there are range designators in designator list, push a new designator 5553 to constructor_range_stack. RANGE_END is end of such stack range or 5554 NULL_TREE if there is no range designator at this level. */ 5555 5556static void 5557push_range_stack (tree range_end) 5558{ 5559 struct constructor_range_stack *p; 5560 5561 p = GGC_NEW (struct constructor_range_stack); 5562 p->prev = constructor_range_stack; 5563 p->next = 0; 5564 p->fields = constructor_fields; 5565 p->range_start = constructor_index; 5566 p->index = constructor_index; 5567 p->stack = constructor_stack; 5568 p->range_end = range_end; 5569 if (constructor_range_stack) 5570 constructor_range_stack->next = p; 5571 constructor_range_stack = p; 5572} 5573 5574/* Within an array initializer, specify the next index to be initialized. 5575 FIRST is that index. If LAST is nonzero, then initialize a range 5576 of indices, running from FIRST through LAST. */ 5577 5578void 5579set_init_index (tree first, tree last) 5580{ 5581 if (set_designator (1)) 5582 return; 5583 5584 designator_erroneous = 1; 5585 5586 if (!INTEGRAL_TYPE_P (TREE_TYPE (first)) 5587 || (last && !INTEGRAL_TYPE_P (TREE_TYPE (last)))) 5588 { 5589 error_init ("array index in initializer not of integer type"); 5590 return; 5591 } 5592 5593 if (TREE_CODE (first) != INTEGER_CST) 5594 error_init ("nonconstant array index in initializer"); 5595 else if (last != 0 && TREE_CODE (last) != INTEGER_CST) 5596 error_init ("nonconstant array index in initializer"); 5597 else if (TREE_CODE (constructor_type) != ARRAY_TYPE) 5598 error_init ("array index in non-array initializer"); 5599 else if (tree_int_cst_sgn (first) == -1) 5600 error_init ("array index in initializer exceeds array bounds"); 5601 else if (constructor_max_index 5602 && tree_int_cst_lt (constructor_max_index, first)) 5603 error_init ("array index in initializer exceeds array bounds"); 5604 else 5605 { 5606 constructor_index = convert (bitsizetype, first); 5607 5608 if (last) 5609 { 5610 if (tree_int_cst_equal (first, last)) 5611 last = 0; 5612 else if (tree_int_cst_lt (last, first)) 5613 { 5614 error_init ("empty index range in initializer"); 5615 last = 0; 5616 } 5617 else 5618 { 5619 last = convert (bitsizetype, last); 5620 if (constructor_max_index != 0 5621 && tree_int_cst_lt (constructor_max_index, last)) 5622 { 5623 error_init ("array index range in initializer exceeds array bounds"); 5624 last = 0; 5625 } 5626 } 5627 } 5628 5629 designator_depth++; 5630 designator_erroneous = 0; 5631 if (constructor_range_stack || last) 5632 push_range_stack (last); 5633 } 5634} 5635 5636/* Within a struct initializer, specify the next field to be initialized. */ 5637 5638void 5639set_init_label (tree fieldname) 5640{ 5641 tree tail; 5642 5643 if (set_designator (0)) 5644 return; 5645 5646 designator_erroneous = 1; 5647 5648 if (TREE_CODE (constructor_type) != RECORD_TYPE 5649 && TREE_CODE (constructor_type) != UNION_TYPE) 5650 { 5651 error_init ("field name not in record or union initializer"); 5652 return; 5653 } 5654 5655 for (tail = TYPE_FIELDS (constructor_type); tail; 5656 tail = TREE_CHAIN (tail)) 5657 { 5658 if (DECL_NAME (tail) == fieldname) 5659 break; 5660 } 5661 5662 if (tail == 0) 5663 error ("unknown field %qE specified in initializer", fieldname); 5664 else 5665 { 5666 constructor_fields = tail; 5667 designator_depth++; 5668 designator_erroneous = 0; 5669 if (constructor_range_stack) 5670 push_range_stack (NULL_TREE); 5671 } 5672} 5673 5674/* Add a new initializer to the tree of pending initializers. PURPOSE 5675 identifies the initializer, either array index or field in a structure. 5676 VALUE is the value of that index or field. */ 5677 5678static void 5679add_pending_init (tree purpose, tree value) 5680{ 5681 struct init_node *p, **q, *r; 5682 5683 q = &constructor_pending_elts; 5684 p = 0; 5685 5686 if (TREE_CODE (constructor_type) == ARRAY_TYPE) 5687 { 5688 while (*q != 0) 5689 { 5690 p = *q; 5691 if (tree_int_cst_lt (purpose, p->purpose)) 5692 q = &p->left; 5693 else if (tree_int_cst_lt (p->purpose, purpose)) 5694 q = &p->right; 5695 else 5696 { 5697 if (TREE_SIDE_EFFECTS (p->value)) 5698 warning_init ("initialized field with side-effects overwritten"); 5699 else if (warn_override_init) 5700 warning_init ("initialized field overwritten"); 5701 p->value = value; 5702 return; 5703 } 5704 } 5705 } 5706 else 5707 { 5708 tree bitpos; 5709 5710 bitpos = bit_position (purpose); 5711 while (*q != NULL) 5712 { 5713 p = *q; 5714 if (tree_int_cst_lt (bitpos, bit_position (p->purpose))) 5715 q = &p->left; 5716 else if (p->purpose != purpose) 5717 q = &p->right; 5718 else 5719 { 5720 if (TREE_SIDE_EFFECTS (p->value)) 5721 warning_init ("initialized field with side-effects overwritten"); 5722 else if (warn_override_init) 5723 warning_init ("initialized field overwritten"); 5724 p->value = value; 5725 return; 5726 } 5727 } 5728 } 5729 5730 r = GGC_NEW (struct init_node); 5731 r->purpose = purpose; 5732 r->value = value; 5733 5734 *q = r; 5735 r->parent = p; 5736 r->left = 0; 5737 r->right = 0; 5738 r->balance = 0; 5739 5740 while (p) 5741 { 5742 struct init_node *s; 5743 5744 if (r == p->left) 5745 { 5746 if (p->balance == 0) 5747 p->balance = -1; 5748 else if (p->balance < 0) 5749 { 5750 if (r->balance < 0) 5751 { 5752 /* L rotation. */ 5753 p->left = r->right; 5754 if (p->left) 5755 p->left->parent = p; 5756 r->right = p; 5757 5758 p->balance = 0; 5759 r->balance = 0; 5760 5761 s = p->parent; 5762 p->parent = r; 5763 r->parent = s; 5764 if (s) 5765 { 5766 if (s->left == p) 5767 s->left = r; 5768 else 5769 s->right = r; 5770 } 5771 else 5772 constructor_pending_elts = r; 5773 } 5774 else 5775 { 5776 /* LR rotation. */ 5777 struct init_node *t = r->right; 5778 5779 r->right = t->left; 5780 if (r->right) 5781 r->right->parent = r; 5782 t->left = r; 5783 5784 p->left = t->right; 5785 if (p->left) 5786 p->left->parent = p; 5787 t->right = p; 5788 5789 p->balance = t->balance < 0; 5790 r->balance = -(t->balance > 0); 5791 t->balance = 0; 5792 5793 s = p->parent; 5794 p->parent = t; 5795 r->parent = t; 5796 t->parent = s; 5797 if (s) 5798 { 5799 if (s->left == p) 5800 s->left = t; 5801 else 5802 s->right = t; 5803 } 5804 else 5805 constructor_pending_elts = t; 5806 } 5807 break; 5808 } 5809 else 5810 { 5811 /* p->balance == +1; growth of left side balances the node. */ 5812 p->balance = 0; 5813 break; 5814 } 5815 } 5816 else /* r == p->right */ 5817 { 5818 if (p->balance == 0) 5819 /* Growth propagation from right side. */ 5820 p->balance++; 5821 else if (p->balance > 0) 5822 { 5823 if (r->balance > 0) 5824 { 5825 /* R rotation. */ 5826 p->right = r->left; 5827 if (p->right) 5828 p->right->parent = p; 5829 r->left = p; 5830 5831 p->balance = 0; 5832 r->balance = 0; 5833 5834 s = p->parent; 5835 p->parent = r; 5836 r->parent = s; 5837 if (s) 5838 { 5839 if (s->left == p) 5840 s->left = r; 5841 else 5842 s->right = r; 5843 } 5844 else 5845 constructor_pending_elts = r; 5846 } 5847 else /* r->balance == -1 */ 5848 { 5849 /* RL rotation */ 5850 struct init_node *t = r->left; 5851 5852 r->left = t->right; 5853 if (r->left) 5854 r->left->parent = r; 5855 t->right = r; 5856 5857 p->right = t->left; 5858 if (p->right) 5859 p->right->parent = p; 5860 t->left = p; 5861 5862 r->balance = (t->balance < 0); 5863 p->balance = -(t->balance > 0); 5864 t->balance = 0; 5865 5866 s = p->parent; 5867 p->parent = t; 5868 r->parent = t; 5869 t->parent = s; 5870 if (s) 5871 { 5872 if (s->left == p) 5873 s->left = t; 5874 else 5875 s->right = t; 5876 } 5877 else 5878 constructor_pending_elts = t; 5879 } 5880 break; 5881 } 5882 else 5883 { 5884 /* p->balance == -1; growth of right side balances the node. */ 5885 p->balance = 0; 5886 break; 5887 } 5888 } 5889 5890 r = p; 5891 p = p->parent; 5892 } 5893} 5894 5895/* Build AVL tree from a sorted chain. */ 5896 5897static void 5898set_nonincremental_init (void) 5899{ 5900 unsigned HOST_WIDE_INT ix; 5901 tree index, value; 5902 5903 if (TREE_CODE (constructor_type) != RECORD_TYPE 5904 && TREE_CODE (constructor_type) != ARRAY_TYPE) 5905 return; 5906 5907 FOR_EACH_CONSTRUCTOR_ELT (constructor_elements, ix, index, value) 5908 add_pending_init (index, value); 5909 constructor_elements = 0; 5910 if (TREE_CODE (constructor_type) == RECORD_TYPE) 5911 { 5912 constructor_unfilled_fields = TYPE_FIELDS (constructor_type); 5913 /* Skip any nameless bit fields at the beginning. */ 5914 while (constructor_unfilled_fields != 0 5915 && DECL_C_BIT_FIELD (constructor_unfilled_fields) 5916 && DECL_NAME (constructor_unfilled_fields) == 0) 5917 constructor_unfilled_fields = TREE_CHAIN (constructor_unfilled_fields); 5918 5919 } 5920 else if (TREE_CODE (constructor_type) == ARRAY_TYPE) 5921 { 5922 if (TYPE_DOMAIN (constructor_type)) 5923 constructor_unfilled_index 5924 = convert (bitsizetype, 5925 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type))); 5926 else 5927 constructor_unfilled_index = bitsize_zero_node; 5928 } 5929 constructor_incremental = 0; 5930} 5931 5932/* Build AVL tree from a string constant. */ 5933 5934static void 5935set_nonincremental_init_from_string (tree str) 5936{ 5937 tree value, purpose, type; 5938 HOST_WIDE_INT val[2]; 5939 const char *p, *end; 5940 int byte, wchar_bytes, charwidth, bitpos; 5941 5942 gcc_assert (TREE_CODE (constructor_type) == ARRAY_TYPE); 5943 5944 if (TYPE_PRECISION (TREE_TYPE (TREE_TYPE (str))) 5945 == TYPE_PRECISION (char_type_node)) 5946 wchar_bytes = 1; 5947 else 5948 { 5949 gcc_assert (TYPE_PRECISION (TREE_TYPE (TREE_TYPE (str))) 5950 == TYPE_PRECISION (wchar_type_node)); 5951 wchar_bytes = TYPE_PRECISION (wchar_type_node) / BITS_PER_UNIT; 5952 } 5953 charwidth = TYPE_PRECISION (char_type_node); 5954 type = TREE_TYPE (constructor_type); 5955 p = TREE_STRING_POINTER (str); 5956 end = p + TREE_STRING_LENGTH (str); 5957 5958 for (purpose = bitsize_zero_node; 5959 p < end && !tree_int_cst_lt (constructor_max_index, purpose); 5960 purpose = size_binop (PLUS_EXPR, purpose, bitsize_one_node)) 5961 { 5962 if (wchar_bytes == 1) 5963 { 5964 val[1] = (unsigned char) *p++; 5965 val[0] = 0; 5966 } 5967 else 5968 { 5969 val[0] = 0; 5970 val[1] = 0; 5971 for (byte = 0; byte < wchar_bytes; byte++) 5972 { 5973 if (BYTES_BIG_ENDIAN) 5974 bitpos = (wchar_bytes - byte - 1) * charwidth; 5975 else 5976 bitpos = byte * charwidth; 5977 val[bitpos < HOST_BITS_PER_WIDE_INT] 5978 |= ((unsigned HOST_WIDE_INT) ((unsigned char) *p++)) 5979 << (bitpos % HOST_BITS_PER_WIDE_INT); 5980 } 5981 } 5982 5983 if (!TYPE_UNSIGNED (type)) 5984 { 5985 bitpos = ((wchar_bytes - 1) * charwidth) + HOST_BITS_PER_CHAR; 5986 if (bitpos < HOST_BITS_PER_WIDE_INT) 5987 { 5988 if (val[1] & (((HOST_WIDE_INT) 1) << (bitpos - 1))) 5989 { 5990 val[1] |= ((HOST_WIDE_INT) -1) << bitpos; 5991 val[0] = -1; 5992 } 5993 } 5994 else if (bitpos == HOST_BITS_PER_WIDE_INT) 5995 { 5996 if (val[1] < 0) 5997 val[0] = -1; 5998 } 5999 else if (val[0] & (((HOST_WIDE_INT) 1) 6000 << (bitpos - 1 - HOST_BITS_PER_WIDE_INT))) 6001 val[0] |= ((HOST_WIDE_INT) -1) 6002 << (bitpos - HOST_BITS_PER_WIDE_INT); 6003 } 6004 6005 value = build_int_cst_wide (type, val[1], val[0]); 6006 add_pending_init (purpose, value); 6007 } 6008 6009 constructor_incremental = 0; 6010} 6011 6012/* Return value of FIELD in pending initializer or zero if the field was 6013 not initialized yet. */ 6014 6015static tree 6016find_init_member (tree field) 6017{ 6018 struct init_node *p; 6019 6020 if (TREE_CODE (constructor_type) == ARRAY_TYPE) 6021 { 6022 if (constructor_incremental 6023 && tree_int_cst_lt (field, constructor_unfilled_index)) 6024 set_nonincremental_init (); 6025 6026 p = constructor_pending_elts; 6027 while (p) 6028 { 6029 if (tree_int_cst_lt (field, p->purpose)) 6030 p = p->left; 6031 else if (tree_int_cst_lt (p->purpose, field)) 6032 p = p->right; 6033 else 6034 return p->value; 6035 } 6036 } 6037 else if (TREE_CODE (constructor_type) == RECORD_TYPE) 6038 { 6039 tree bitpos = bit_position (field); 6040 6041 if (constructor_incremental 6042 && (!constructor_unfilled_fields 6043 || tree_int_cst_lt (bitpos, 6044 bit_position (constructor_unfilled_fields)))) 6045 set_nonincremental_init (); 6046 6047 p = constructor_pending_elts; 6048 while (p) 6049 { 6050 if (field == p->purpose) 6051 return p->value; 6052 else if (tree_int_cst_lt (bitpos, bit_position (p->purpose))) 6053 p = p->left; 6054 else 6055 p = p->right; 6056 } 6057 } 6058 else if (TREE_CODE (constructor_type) == UNION_TYPE) 6059 { 6060 if (!VEC_empty (constructor_elt, constructor_elements) 6061 && (VEC_last (constructor_elt, constructor_elements)->index 6062 == field)) 6063 return VEC_last (constructor_elt, constructor_elements)->value; 6064 } 6065 return 0; 6066} 6067 6068/* "Output" the next constructor element. 6069 At top level, really output it to assembler code now. 6070 Otherwise, collect it in a list from which we will make a CONSTRUCTOR. 6071 TYPE is the data type that the containing data type wants here. 6072 FIELD is the field (a FIELD_DECL) or the index that this element fills. 6073 If VALUE is a string constant, STRICT_STRING is true if it is 6074 unparenthesized or we should not warn here for it being parenthesized. 6075 For other types of VALUE, STRICT_STRING is not used. 6076 6077 PENDING if non-nil means output pending elements that belong 6078 right after this element. (PENDING is normally 1; 6079 it is 0 while outputting pending elements, to avoid recursion.) */ 6080 6081static void 6082output_init_element (tree value, bool strict_string, tree type, tree field, 6083 int pending) 6084{ 6085 constructor_elt *celt; 6086 6087 if (type == error_mark_node || value == error_mark_node) 6088 { 6089 constructor_erroneous = 1; 6090 return; 6091 } 6092 if (TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE 6093 && (TREE_CODE (value) == STRING_CST 6094 || TREE_CODE (value) == COMPOUND_LITERAL_EXPR) 6095 && !(TREE_CODE (value) == STRING_CST 6096 && TREE_CODE (type) == ARRAY_TYPE 6097 && INTEGRAL_TYPE_P (TREE_TYPE (type))) 6098 && !comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (value)), 6099 TYPE_MAIN_VARIANT (type))) 6100 value = array_to_pointer_conversion (value); 6101 6102 if (TREE_CODE (value) == COMPOUND_LITERAL_EXPR 6103 && require_constant_value && !flag_isoc99 && pending) 6104 { 6105 /* As an extension, allow initializing objects with static storage 6106 duration with compound literals (which are then treated just as 6107 the brace enclosed list they contain). */ 6108 tree decl = COMPOUND_LITERAL_EXPR_DECL (value); 6109 value = DECL_INITIAL (decl); 6110 } 6111 6112 if (value == error_mark_node) 6113 constructor_erroneous = 1; 6114 else if (!TREE_CONSTANT (value)) 6115 constructor_constant = 0; 6116 else if (!initializer_constant_valid_p (value, TREE_TYPE (value)) 6117 || ((TREE_CODE (constructor_type) == RECORD_TYPE 6118 || TREE_CODE (constructor_type) == UNION_TYPE) 6119 && DECL_C_BIT_FIELD (field) 6120 && TREE_CODE (value) != INTEGER_CST)) 6121 constructor_simple = 0; 6122 6123 if (!initializer_constant_valid_p (value, TREE_TYPE (value))) 6124 { 6125 if (require_constant_value) 6126 { 6127 error_init ("initializer element is not constant"); 6128 value = error_mark_node; 6129 } 6130 else if (require_constant_elements) 6131 pedwarn ("initializer element is not computable at load time"); 6132 } 6133 6134 /* If this field is empty (and not at the end of structure), 6135 don't do anything other than checking the initializer. */ 6136 if (field 6137 && (TREE_TYPE (field) == error_mark_node 6138 || (COMPLETE_TYPE_P (TREE_TYPE (field)) 6139 && integer_zerop (TYPE_SIZE (TREE_TYPE (field))) 6140 && (TREE_CODE (constructor_type) == ARRAY_TYPE 6141 || TREE_CHAIN (field))))) 6142 return; 6143 6144 value = digest_init (type, value, strict_string, require_constant_value); 6145 if (value == error_mark_node) 6146 { 6147 constructor_erroneous = 1; 6148 return; 6149 } 6150 6151 /* If this element doesn't come next in sequence, 6152 put it on constructor_pending_elts. */ 6153 if (TREE_CODE (constructor_type) == ARRAY_TYPE 6154 && (!constructor_incremental 6155 || !tree_int_cst_equal (field, constructor_unfilled_index))) 6156 { 6157 if (constructor_incremental 6158 && tree_int_cst_lt (field, constructor_unfilled_index)) 6159 set_nonincremental_init (); 6160 6161 add_pending_init (field, value); 6162 return; 6163 } 6164 else if (TREE_CODE (constructor_type) == RECORD_TYPE 6165 && (!constructor_incremental 6166 || field != constructor_unfilled_fields)) 6167 { 6168 /* We do this for records but not for unions. In a union, 6169 no matter which field is specified, it can be initialized 6170 right away since it starts at the beginning of the union. */ 6171 if (constructor_incremental) 6172 { 6173 if (!constructor_unfilled_fields) 6174 set_nonincremental_init (); 6175 else 6176 { 6177 tree bitpos, unfillpos; 6178 6179 bitpos = bit_position (field); 6180 unfillpos = bit_position (constructor_unfilled_fields); 6181 6182 if (tree_int_cst_lt (bitpos, unfillpos)) 6183 set_nonincremental_init (); 6184 } 6185 } 6186 6187 add_pending_init (field, value); 6188 return; 6189 } 6190 else if (TREE_CODE (constructor_type) == UNION_TYPE 6191 && !VEC_empty (constructor_elt, constructor_elements)) 6192 { 6193 if (TREE_SIDE_EFFECTS (VEC_last (constructor_elt, 6194 constructor_elements)->value)) 6195 warning_init ("initialized field with side-effects overwritten"); 6196 else if (warn_override_init) 6197 warning_init ("initialized field overwritten"); 6198 6199 /* We can have just one union field set. */ 6200 constructor_elements = 0; 6201 } 6202 6203 /* Otherwise, output this element either to 6204 constructor_elements or to the assembler file. */ 6205 6206 celt = VEC_safe_push (constructor_elt, gc, constructor_elements, NULL); 6207 celt->index = field; 6208 celt->value = value; 6209 6210 /* Advance the variable that indicates sequential elements output. */ 6211 if (TREE_CODE (constructor_type) == ARRAY_TYPE) 6212 constructor_unfilled_index 6213 = size_binop (PLUS_EXPR, constructor_unfilled_index, 6214 bitsize_one_node); 6215 else if (TREE_CODE (constructor_type) == RECORD_TYPE) 6216 { 6217 constructor_unfilled_fields 6218 = TREE_CHAIN (constructor_unfilled_fields); 6219 6220 /* Skip any nameless bit fields. */ 6221 while (constructor_unfilled_fields != 0 6222 && DECL_C_BIT_FIELD (constructor_unfilled_fields) 6223 && DECL_NAME (constructor_unfilled_fields) == 0) 6224 constructor_unfilled_fields = 6225 TREE_CHAIN (constructor_unfilled_fields); 6226 } 6227 else if (TREE_CODE (constructor_type) == UNION_TYPE) 6228 constructor_unfilled_fields = 0; 6229 6230 /* Now output any pending elements which have become next. */ 6231 if (pending) 6232 output_pending_init_elements (0); 6233} 6234 6235/* Output any pending elements which have become next. 6236 As we output elements, constructor_unfilled_{fields,index} 6237 advances, which may cause other elements to become next; 6238 if so, they too are output. 6239 6240 If ALL is 0, we return when there are 6241 no more pending elements to output now. 6242 6243 If ALL is 1, we output space as necessary so that 6244 we can output all the pending elements. */ 6245 6246static void 6247output_pending_init_elements (int all) 6248{ 6249 struct init_node *elt = constructor_pending_elts; 6250 tree next; 6251 6252 retry: 6253 6254 /* Look through the whole pending tree. 6255 If we find an element that should be output now, 6256 output it. Otherwise, set NEXT to the element 6257 that comes first among those still pending. */ 6258 6259 next = 0; 6260 while (elt) 6261 { 6262 if (TREE_CODE (constructor_type) == ARRAY_TYPE) 6263 { 6264 if (tree_int_cst_equal (elt->purpose, 6265 constructor_unfilled_index)) 6266 output_init_element (elt->value, true, 6267 TREE_TYPE (constructor_type), 6268 constructor_unfilled_index, 0); 6269 else if (tree_int_cst_lt (constructor_unfilled_index, 6270 elt->purpose)) 6271 { 6272 /* Advance to the next smaller node. */ 6273 if (elt->left) 6274 elt = elt->left; 6275 else 6276 { 6277 /* We have reached the smallest node bigger than the 6278 current unfilled index. Fill the space first. */ 6279 next = elt->purpose; 6280 break; 6281 } 6282 } 6283 else 6284 { 6285 /* Advance to the next bigger node. */ 6286 if (elt->right) 6287 elt = elt->right; 6288 else 6289 { 6290 /* We have reached the biggest node in a subtree. Find 6291 the parent of it, which is the next bigger node. */ 6292 while (elt->parent && elt->parent->right == elt) 6293 elt = elt->parent; 6294 elt = elt->parent; 6295 if (elt && tree_int_cst_lt (constructor_unfilled_index, 6296 elt->purpose)) 6297 { 6298 next = elt->purpose; 6299 break; 6300 } 6301 } 6302 } 6303 } 6304 else if (TREE_CODE (constructor_type) == RECORD_TYPE 6305 || TREE_CODE (constructor_type) == UNION_TYPE) 6306 { 6307 tree ctor_unfilled_bitpos, elt_bitpos; 6308 6309 /* If the current record is complete we are done. */ 6310 if (constructor_unfilled_fields == 0) 6311 break; 6312 6313 ctor_unfilled_bitpos = bit_position (constructor_unfilled_fields); 6314 elt_bitpos = bit_position (elt->purpose); 6315 /* We can't compare fields here because there might be empty 6316 fields in between. */ 6317 if (tree_int_cst_equal (elt_bitpos, ctor_unfilled_bitpos)) 6318 { 6319 constructor_unfilled_fields = elt->purpose; 6320 output_init_element (elt->value, true, TREE_TYPE (elt->purpose), 6321 elt->purpose, 0); 6322 } 6323 else if (tree_int_cst_lt (ctor_unfilled_bitpos, elt_bitpos)) 6324 { 6325 /* Advance to the next smaller node. */ 6326 if (elt->left) 6327 elt = elt->left; 6328 else 6329 { 6330 /* We have reached the smallest node bigger than the 6331 current unfilled field. Fill the space first. */ 6332 next = elt->purpose; 6333 break; 6334 } 6335 } 6336 else 6337 { 6338 /* Advance to the next bigger node. */ 6339 if (elt->right) 6340 elt = elt->right; 6341 else 6342 { 6343 /* We have reached the biggest node in a subtree. Find 6344 the parent of it, which is the next bigger node. */ 6345 while (elt->parent && elt->parent->right == elt) 6346 elt = elt->parent; 6347 elt = elt->parent; 6348 if (elt 6349 && (tree_int_cst_lt (ctor_unfilled_bitpos, 6350 bit_position (elt->purpose)))) 6351 { 6352 next = elt->purpose; 6353 break; 6354 } 6355 } 6356 } 6357 } 6358 } 6359 6360 /* Ordinarily return, but not if we want to output all 6361 and there are elements left. */ 6362 if (!(all && next != 0)) 6363 return; 6364 6365 /* If it's not incremental, just skip over the gap, so that after 6366 jumping to retry we will output the next successive element. */ 6367 if (TREE_CODE (constructor_type) == RECORD_TYPE 6368 || TREE_CODE (constructor_type) == UNION_TYPE) 6369 constructor_unfilled_fields = next; 6370 else if (TREE_CODE (constructor_type) == ARRAY_TYPE) 6371 constructor_unfilled_index = next; 6372 6373 /* ELT now points to the node in the pending tree with the next 6374 initializer to output. */ 6375 goto retry; 6376} 6377 6378/* Add one non-braced element to the current constructor level. 6379 This adjusts the current position within the constructor's type. 6380 This may also start or terminate implicit levels 6381 to handle a partly-braced initializer. 6382 6383 Once this has found the correct level for the new element, 6384 it calls output_init_element. */ 6385 6386void 6387process_init_element (struct c_expr value) 6388{ 6389 tree orig_value = value.value; 6390 int string_flag = orig_value != 0 && TREE_CODE (orig_value) == STRING_CST; 6391 bool strict_string = value.original_code == STRING_CST; 6392 6393 designator_depth = 0; 6394 designator_erroneous = 0; 6395 6396 /* Handle superfluous braces around string cst as in 6397 char x[] = {"foo"}; */ 6398 if (string_flag 6399 && constructor_type 6400 && TREE_CODE (constructor_type) == ARRAY_TYPE 6401 && INTEGRAL_TYPE_P (TREE_TYPE (constructor_type)) 6402 && integer_zerop (constructor_unfilled_index)) 6403 { 6404 if (constructor_stack->replacement_value.value) 6405 error_init ("excess elements in char array initializer"); 6406 constructor_stack->replacement_value = value; 6407 return; 6408 } 6409 6410 if (constructor_stack->replacement_value.value != 0) 6411 { 6412 error_init ("excess elements in struct initializer"); 6413 return; 6414 } 6415 6416 /* Ignore elements of a brace group if it is entirely superfluous 6417 and has already been diagnosed. */ 6418 if (constructor_type == 0) 6419 return; 6420 6421 /* If we've exhausted any levels that didn't have braces, 6422 pop them now. */ 6423 while (constructor_stack->implicit) 6424 { 6425 if ((TREE_CODE (constructor_type) == RECORD_TYPE 6426 || TREE_CODE (constructor_type) == UNION_TYPE) 6427 && constructor_fields == 0) 6428 process_init_element (pop_init_level (1)); 6429 else if (TREE_CODE (constructor_type) == ARRAY_TYPE 6430 && (constructor_max_index == 0 6431 || tree_int_cst_lt (constructor_max_index, 6432 constructor_index))) 6433 process_init_element (pop_init_level (1)); 6434 else 6435 break; 6436 } 6437 6438 /* In the case of [LO ... HI] = VALUE, only evaluate VALUE once. */ 6439 if (constructor_range_stack) 6440 { 6441 /* If value is a compound literal and we'll be just using its 6442 content, don't put it into a SAVE_EXPR. */ 6443 if (TREE_CODE (value.value) != COMPOUND_LITERAL_EXPR 6444 || !require_constant_value 6445 || flag_isoc99) 6446 value.value = save_expr (value.value); 6447 } 6448 6449 while (1) 6450 { 6451 if (TREE_CODE (constructor_type) == RECORD_TYPE) 6452 { 6453 tree fieldtype; 6454 enum tree_code fieldcode; 6455 6456 if (constructor_fields == 0) 6457 { 6458 pedwarn_init ("excess elements in struct initializer"); 6459 break; 6460 } 6461 6462 fieldtype = TREE_TYPE (constructor_fields); 6463 if (fieldtype != error_mark_node) 6464 fieldtype = TYPE_MAIN_VARIANT (fieldtype); 6465 fieldcode = TREE_CODE (fieldtype); 6466 6467 /* Error for non-static initialization of a flexible array member. */ 6468 if (fieldcode == ARRAY_TYPE 6469 && !require_constant_value 6470 && TYPE_SIZE (fieldtype) == NULL_TREE 6471 && TREE_CHAIN (constructor_fields) == NULL_TREE) 6472 { 6473 error_init ("non-static initialization of a flexible array member"); 6474 break; 6475 } 6476 6477 /* Accept a string constant to initialize a subarray. */ 6478 if (value.value != 0 6479 && fieldcode == ARRAY_TYPE 6480 && INTEGRAL_TYPE_P (TREE_TYPE (fieldtype)) 6481 && string_flag) 6482 value.value = orig_value; 6483 /* Otherwise, if we have come to a subaggregate, 6484 and we don't have an element of its type, push into it. */ 6485 else if (value.value != 0 6486 && value.value != error_mark_node 6487 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != fieldtype 6488 && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE 6489 || fieldcode == UNION_TYPE)) 6490 { 6491 push_init_level (1); 6492 continue; 6493 } 6494 6495 if (value.value) 6496 { 6497 push_member_name (constructor_fields); 6498 output_init_element (value.value, strict_string, 6499 fieldtype, constructor_fields, 1); 6500 RESTORE_SPELLING_DEPTH (constructor_depth); 6501 } 6502 else 6503 /* Do the bookkeeping for an element that was 6504 directly output as a constructor. */ 6505 { 6506 /* For a record, keep track of end position of last field. */ 6507 if (DECL_SIZE (constructor_fields)) 6508 constructor_bit_index 6509 = size_binop (PLUS_EXPR, 6510 bit_position (constructor_fields), 6511 DECL_SIZE (constructor_fields)); 6512 6513 /* If the current field was the first one not yet written out, 6514 it isn't now, so update. */ 6515 if (constructor_unfilled_fields == constructor_fields) 6516 { 6517 constructor_unfilled_fields = TREE_CHAIN (constructor_fields); 6518 /* Skip any nameless bit fields. */ 6519 while (constructor_unfilled_fields != 0 6520 && DECL_C_BIT_FIELD (constructor_unfilled_fields) 6521 && DECL_NAME (constructor_unfilled_fields) == 0) 6522 constructor_unfilled_fields = 6523 TREE_CHAIN (constructor_unfilled_fields); 6524 } 6525 } 6526 6527 constructor_fields = TREE_CHAIN (constructor_fields); 6528 /* Skip any nameless bit fields at the beginning. */ 6529 while (constructor_fields != 0 6530 && DECL_C_BIT_FIELD (constructor_fields) 6531 && DECL_NAME (constructor_fields) == 0) 6532 constructor_fields = TREE_CHAIN (constructor_fields); 6533 } 6534 else if (TREE_CODE (constructor_type) == UNION_TYPE) 6535 { 6536 tree fieldtype; 6537 enum tree_code fieldcode; 6538 6539 if (constructor_fields == 0) 6540 { 6541 pedwarn_init ("excess elements in union initializer"); 6542 break; 6543 } 6544 6545 fieldtype = TREE_TYPE (constructor_fields); 6546 if (fieldtype != error_mark_node) 6547 fieldtype = TYPE_MAIN_VARIANT (fieldtype); 6548 fieldcode = TREE_CODE (fieldtype); 6549 6550 /* Warn that traditional C rejects initialization of unions. 6551 We skip the warning if the value is zero. This is done 6552 under the assumption that the zero initializer in user 6553 code appears conditioned on e.g. __STDC__ to avoid 6554 "missing initializer" warnings and relies on default 6555 initialization to zero in the traditional C case. 6556 We also skip the warning if the initializer is designated, 6557 again on the assumption that this must be conditional on 6558 __STDC__ anyway (and we've already complained about the 6559 member-designator already). */ 6560 if (!in_system_header && !constructor_designated 6561 && !(value.value && (integer_zerop (value.value) 6562 || real_zerop (value.value)))) 6563 warning (OPT_Wtraditional, "traditional C rejects initialization " 6564 "of unions"); 6565 6566 /* Accept a string constant to initialize a subarray. */ 6567 if (value.value != 0 6568 && fieldcode == ARRAY_TYPE 6569 && INTEGRAL_TYPE_P (TREE_TYPE (fieldtype)) 6570 && string_flag) 6571 value.value = orig_value; 6572 /* Otherwise, if we have come to a subaggregate, 6573 and we don't have an element of its type, push into it. */ 6574 else if (value.value != 0 6575 && value.value != error_mark_node 6576 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != fieldtype 6577 && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE 6578 || fieldcode == UNION_TYPE)) 6579 { 6580 push_init_level (1); 6581 continue; 6582 } 6583 6584 if (value.value) 6585 { 6586 push_member_name (constructor_fields); 6587 output_init_element (value.value, strict_string, 6588 fieldtype, constructor_fields, 1); 6589 RESTORE_SPELLING_DEPTH (constructor_depth); 6590 } 6591 else 6592 /* Do the bookkeeping for an element that was 6593 directly output as a constructor. */ 6594 { 6595 constructor_bit_index = DECL_SIZE (constructor_fields); 6596 constructor_unfilled_fields = TREE_CHAIN (constructor_fields); 6597 } 6598 6599 constructor_fields = 0; 6600 } 6601 else if (TREE_CODE (constructor_type) == ARRAY_TYPE) 6602 { 6603 tree elttype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type)); 6604 enum tree_code eltcode = TREE_CODE (elttype); 6605 6606 /* Accept a string constant to initialize a subarray. */ 6607 if (value.value != 0 6608 && eltcode == ARRAY_TYPE 6609 && INTEGRAL_TYPE_P (TREE_TYPE (elttype)) 6610 && string_flag) 6611 value.value = orig_value; 6612 /* Otherwise, if we have come to a subaggregate, 6613 and we don't have an element of its type, push into it. */ 6614 else if (value.value != 0 6615 && value.value != error_mark_node 6616 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != elttype 6617 && (eltcode == RECORD_TYPE || eltcode == ARRAY_TYPE 6618 || eltcode == UNION_TYPE)) 6619 { 6620 push_init_level (1); 6621 continue; 6622 } 6623 6624 if (constructor_max_index != 0 6625 && (tree_int_cst_lt (constructor_max_index, constructor_index) 6626 || integer_all_onesp (constructor_max_index))) 6627 { 6628 pedwarn_init ("excess elements in array initializer"); 6629 break; 6630 } 6631 6632 /* Now output the actual element. */ 6633 if (value.value) 6634 { 6635 push_array_bounds (tree_low_cst (constructor_index, 1)); 6636 output_init_element (value.value, strict_string, 6637 elttype, constructor_index, 1); 6638 RESTORE_SPELLING_DEPTH (constructor_depth); 6639 } 6640 6641 constructor_index 6642 = size_binop (PLUS_EXPR, constructor_index, bitsize_one_node); 6643 6644 if (!value.value) 6645 /* If we are doing the bookkeeping for an element that was 6646 directly output as a constructor, we must update 6647 constructor_unfilled_index. */ 6648 constructor_unfilled_index = constructor_index; 6649 } 6650 else if (TREE_CODE (constructor_type) == VECTOR_TYPE) 6651 { 6652 tree elttype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type)); 6653 6654 /* Do a basic check of initializer size. Note that vectors 6655 always have a fixed size derived from their type. */ 6656 if (tree_int_cst_lt (constructor_max_index, constructor_index)) 6657 { 6658 pedwarn_init ("excess elements in vector initializer"); 6659 break; 6660 } 6661 6662 /* Now output the actual element. */ 6663 if (value.value) 6664 output_init_element (value.value, strict_string, 6665 elttype, constructor_index, 1); 6666 6667 constructor_index 6668 = size_binop (PLUS_EXPR, constructor_index, bitsize_one_node); 6669 6670 if (!value.value) 6671 /* If we are doing the bookkeeping for an element that was 6672 directly output as a constructor, we must update 6673 constructor_unfilled_index. */ 6674 constructor_unfilled_index = constructor_index; 6675 } 6676 6677 /* Handle the sole element allowed in a braced initializer 6678 for a scalar variable. */ 6679 else if (constructor_type != error_mark_node 6680 && constructor_fields == 0) 6681 { 6682 pedwarn_init ("excess elements in scalar initializer"); 6683 break; 6684 } 6685 else 6686 { 6687 if (value.value) 6688 output_init_element (value.value, strict_string, 6689 constructor_type, NULL_TREE, 1); 6690 constructor_fields = 0; 6691 } 6692 6693 /* Handle range initializers either at this level or anywhere higher 6694 in the designator stack. */ 6695 if (constructor_range_stack) 6696 { 6697 struct constructor_range_stack *p, *range_stack; 6698 int finish = 0; 6699 6700 range_stack = constructor_range_stack; 6701 constructor_range_stack = 0; 6702 while (constructor_stack != range_stack->stack) 6703 { 6704 gcc_assert (constructor_stack->implicit); 6705 process_init_element (pop_init_level (1)); 6706 } 6707 for (p = range_stack; 6708 !p->range_end || tree_int_cst_equal (p->index, p->range_end); 6709 p = p->prev) 6710 { 6711 gcc_assert (constructor_stack->implicit); 6712 process_init_element (pop_init_level (1)); 6713 } 6714 6715 p->index = size_binop (PLUS_EXPR, p->index, bitsize_one_node); 6716 if (tree_int_cst_equal (p->index, p->range_end) && !p->prev) 6717 finish = 1; 6718 6719 while (1) 6720 { 6721 constructor_index = p->index; 6722 constructor_fields = p->fields; 6723 if (finish && p->range_end && p->index == p->range_start) 6724 { 6725 finish = 0; 6726 p->prev = 0; 6727 } 6728 p = p->next; 6729 if (!p) 6730 break; 6731 push_init_level (2); 6732 p->stack = constructor_stack; 6733 if (p->range_end && tree_int_cst_equal (p->index, p->range_end)) 6734 p->index = p->range_start; 6735 } 6736 6737 if (!finish) 6738 constructor_range_stack = range_stack; 6739 continue; 6740 } 6741 6742 break; 6743 } 6744 6745 constructor_range_stack = 0; 6746} 6747 6748/* Build a complete asm-statement, whose components are a CV_QUALIFIER 6749 (guaranteed to be 'volatile' or null) and ARGS (represented using 6750 an ASM_EXPR node). */ 6751tree 6752build_asm_stmt (tree cv_qualifier, tree args) 6753{ 6754 if (!ASM_VOLATILE_P (args) && cv_qualifier) 6755 ASM_VOLATILE_P (args) = 1; 6756 return add_stmt (args); 6757} 6758 6759/* Build an asm-expr, whose components are a STRING, some OUTPUTS, 6760 some INPUTS, and some CLOBBERS. The latter three may be NULL. 6761 SIMPLE indicates whether there was anything at all after the 6762 string in the asm expression -- asm("blah") and asm("blah" : ) 6763 are subtly different. We use a ASM_EXPR node to represent this. */ 6764tree 6765build_asm_expr (tree string, tree outputs, tree inputs, tree clobbers, 6766 bool simple) 6767{ 6768 tree tail; 6769 tree args; 6770 int i; 6771 const char *constraint; 6772 const char **oconstraints; 6773 bool allows_mem, allows_reg, is_inout; 6774 int ninputs, noutputs; 6775 6776 ninputs = list_length (inputs); 6777 noutputs = list_length (outputs); 6778 oconstraints = (const char **) alloca (noutputs * sizeof (const char *)); 6779 6780 string = resolve_asm_operand_names (string, outputs, inputs); 6781 6782 /* Remove output conversions that change the type but not the mode. */ 6783 for (i = 0, tail = outputs; tail; ++i, tail = TREE_CHAIN (tail)) 6784 { 6785 tree output = TREE_VALUE (tail); 6786 6787 /* ??? Really, this should not be here. Users should be using a 6788 proper lvalue, dammit. But there's a long history of using casts 6789 in the output operands. In cases like longlong.h, this becomes a 6790 primitive form of typechecking -- if the cast can be removed, then 6791 the output operand had a type of the proper width; otherwise we'll 6792 get an error. Gross, but ... */ 6793 STRIP_NOPS (output); 6794 6795 if (!lvalue_or_else (output, lv_asm)) 6796 output = error_mark_node; 6797 6798 if (output != error_mark_node 6799 && (TREE_READONLY (output) 6800 || TYPE_READONLY (TREE_TYPE (output)) 6801 || ((TREE_CODE (TREE_TYPE (output)) == RECORD_TYPE 6802 || TREE_CODE (TREE_TYPE (output)) == UNION_TYPE) 6803 && C_TYPE_FIELDS_READONLY (TREE_TYPE (output))))) 6804 readonly_error (output, lv_asm); 6805 6806 constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (tail))); 6807 oconstraints[i] = constraint; 6808 6809 if (parse_output_constraint (&constraint, i, ninputs, noutputs, 6810 &allows_mem, &allows_reg, &is_inout)) 6811 { 6812 /* If the operand is going to end up in memory, 6813 mark it addressable. */ 6814 if (!allows_reg && !c_mark_addressable (output)) 6815 output = error_mark_node; 6816 } 6817 else 6818 output = error_mark_node; 6819 6820 TREE_VALUE (tail) = output; 6821 } 6822 6823 for (i = 0, tail = inputs; tail; ++i, tail = TREE_CHAIN (tail)) 6824 { 6825 tree input; 6826 6827 constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (tail))); 6828 input = TREE_VALUE (tail); 6829 6830 if (parse_input_constraint (&constraint, i, ninputs, noutputs, 0, 6831 oconstraints, &allows_mem, &allows_reg)) 6832 { 6833 /* If the operand is going to end up in memory, 6834 mark it addressable. */ 6835 if (!allows_reg && allows_mem) 6836 { 6837 /* Strip the nops as we allow this case. FIXME, this really 6838 should be rejected or made deprecated. */ 6839 STRIP_NOPS (input); 6840 if (!c_mark_addressable (input)) 6841 input = error_mark_node; 6842 } 6843 } 6844 else 6845 input = error_mark_node; 6846 6847 TREE_VALUE (tail) = input; 6848 } 6849 6850 args = build_stmt (ASM_EXPR, string, outputs, inputs, clobbers); 6851 6852 /* asm statements without outputs, including simple ones, are treated 6853 as volatile. */ 6854 ASM_INPUT_P (args) = simple; 6855 ASM_VOLATILE_P (args) = (noutputs == 0); 6856 6857 return args; 6858} 6859 6860/* Generate a goto statement to LABEL. */ 6861 6862tree 6863c_finish_goto_label (tree label) 6864{ 6865 tree decl = lookup_label (label); 6866 if (!decl) 6867 return NULL_TREE; 6868 6869 if (C_DECL_UNJUMPABLE_STMT_EXPR (decl)) 6870 { 6871 error ("jump into statement expression"); 6872 return NULL_TREE; 6873 } 6874 6875 if (C_DECL_UNJUMPABLE_VM (decl)) 6876 { 6877 error ("jump into scope of identifier with variably modified type"); 6878 return NULL_TREE; 6879 } 6880 6881 if (!C_DECL_UNDEFINABLE_STMT_EXPR (decl)) 6882 { 6883 /* No jump from outside this statement expression context, so 6884 record that there is a jump from within this context. */ 6885 struct c_label_list *nlist; 6886 nlist = XOBNEW (&parser_obstack, struct c_label_list); 6887 nlist->next = label_context_stack_se->labels_used; 6888 nlist->label = decl; 6889 label_context_stack_se->labels_used = nlist; 6890 } 6891 6892 if (!C_DECL_UNDEFINABLE_VM (decl)) 6893 { 6894 /* No jump from outside this context context of identifiers with 6895 variably modified type, so record that there is a jump from 6896 within this context. */ 6897 struct c_label_list *nlist; 6898 nlist = XOBNEW (&parser_obstack, struct c_label_list); 6899 nlist->next = label_context_stack_vm->labels_used; 6900 nlist->label = decl; 6901 label_context_stack_vm->labels_used = nlist; 6902 } 6903 6904 TREE_USED (decl) = 1; 6905 return add_stmt (build1 (GOTO_EXPR, void_type_node, decl)); 6906} 6907 6908/* Generate a computed goto statement to EXPR. */ 6909 6910tree 6911c_finish_goto_ptr (tree expr) 6912{ 6913 if (pedantic) 6914 pedwarn ("ISO C forbids %<goto *expr;%>"); 6915 expr = convert (ptr_type_node, expr); 6916 return add_stmt (build1 (GOTO_EXPR, void_type_node, expr)); 6917} 6918 6919/* Generate a C `return' statement. RETVAL is the expression for what 6920 to return, or a null pointer for `return;' with no value. */ 6921 6922tree 6923c_finish_return (tree retval) 6924{ 6925 tree valtype = TREE_TYPE (TREE_TYPE (current_function_decl)), ret_stmt; 6926 bool no_warning = false; 6927 6928 if (TREE_THIS_VOLATILE (current_function_decl)) 6929 warning (0, "function declared %<noreturn%> has a %<return%> statement"); 6930 6931 if (!retval) 6932 { 6933 current_function_returns_null = 1; 6934 if ((warn_return_type || flag_isoc99) 6935 && valtype != 0 && TREE_CODE (valtype) != VOID_TYPE) 6936 { 6937 pedwarn_c99 ("%<return%> with no value, in " 6938 "function returning non-void"); 6939 no_warning = true; 6940 } 6941 } 6942 else if (valtype == 0 || TREE_CODE (valtype) == VOID_TYPE) 6943 { 6944 current_function_returns_null = 1; 6945 if (pedantic || TREE_CODE (TREE_TYPE (retval)) != VOID_TYPE) 6946 pedwarn ("%<return%> with a value, in function returning void"); 6947 } 6948 else 6949 { 6950 tree t = convert_for_assignment (valtype, retval, ic_return, 6951 NULL_TREE, NULL_TREE, 0); 6952 tree res = DECL_RESULT (current_function_decl); 6953 tree inner; 6954 6955 current_function_returns_value = 1; 6956 if (t == error_mark_node) 6957 return NULL_TREE; 6958 6959 inner = t = convert (TREE_TYPE (res), t); 6960 6961 /* Strip any conversions, additions, and subtractions, and see if 6962 we are returning the address of a local variable. Warn if so. */ 6963 while (1) 6964 { 6965 switch (TREE_CODE (inner)) 6966 { 6967 case NOP_EXPR: case NON_LVALUE_EXPR: case CONVERT_EXPR: 6968 case PLUS_EXPR: 6969 inner = TREE_OPERAND (inner, 0); 6970 continue; 6971 6972 case MINUS_EXPR: 6973 /* If the second operand of the MINUS_EXPR has a pointer 6974 type (or is converted from it), this may be valid, so 6975 don't give a warning. */ 6976 { 6977 tree op1 = TREE_OPERAND (inner, 1); 6978 6979 while (!POINTER_TYPE_P (TREE_TYPE (op1)) 6980 && (TREE_CODE (op1) == NOP_EXPR 6981 || TREE_CODE (op1) == NON_LVALUE_EXPR 6982 || TREE_CODE (op1) == CONVERT_EXPR)) 6983 op1 = TREE_OPERAND (op1, 0); 6984 6985 if (POINTER_TYPE_P (TREE_TYPE (op1))) 6986 break; 6987 6988 inner = TREE_OPERAND (inner, 0); 6989 continue; 6990 } 6991 6992 case ADDR_EXPR: 6993 inner = TREE_OPERAND (inner, 0); 6994 6995 while (REFERENCE_CLASS_P (inner) 6996 && TREE_CODE (inner) != INDIRECT_REF) 6997 inner = TREE_OPERAND (inner, 0); 6998 6999 if (DECL_P (inner) 7000 && !DECL_EXTERNAL (inner) 7001 && !TREE_STATIC (inner) 7002 && DECL_CONTEXT (inner) == current_function_decl) 7003 warning (0, "function returns address of local variable"); 7004 break; 7005 7006 default: 7007 break; 7008 } 7009 7010 break; 7011 } 7012 7013 retval = build2 (MODIFY_EXPR, TREE_TYPE (res), res, t); 7014 } 7015 7016 ret_stmt = build_stmt (RETURN_EXPR, retval); 7017 TREE_NO_WARNING (ret_stmt) |= no_warning; 7018 return add_stmt (ret_stmt); 7019} 7020 7021struct c_switch { 7022 /* The SWITCH_EXPR being built. */ 7023 tree switch_expr; 7024 7025 /* The original type of the testing expression, i.e. before the 7026 default conversion is applied. */ 7027 tree orig_type; 7028 7029 /* A splay-tree mapping the low element of a case range to the high 7030 element, or NULL_TREE if there is no high element. Used to 7031 determine whether or not a new case label duplicates an old case 7032 label. We need a tree, rather than simply a hash table, because 7033 of the GNU case range extension. */ 7034 splay_tree cases; 7035 7036 /* Number of nested statement expressions within this switch 7037 statement; if nonzero, case and default labels may not 7038 appear. */ 7039 unsigned int blocked_stmt_expr; 7040 7041 /* Scope of outermost declarations of identifiers with variably 7042 modified type within this switch statement; if nonzero, case and 7043 default labels may not appear. */ 7044 unsigned int blocked_vm; 7045 7046 /* The next node on the stack. */ 7047 struct c_switch *next; 7048}; 7049 7050/* A stack of the currently active switch statements. The innermost 7051 switch statement is on the top of the stack. There is no need to 7052 mark the stack for garbage collection because it is only active 7053 during the processing of the body of a function, and we never 7054 collect at that point. */ 7055 7056struct c_switch *c_switch_stack; 7057 7058/* Start a C switch statement, testing expression EXP. Return the new 7059 SWITCH_EXPR. */ 7060 7061tree 7062c_start_case (tree exp) 7063{ 7064 tree orig_type = error_mark_node; 7065 struct c_switch *cs; 7066 7067 if (exp != error_mark_node) 7068 { 7069 orig_type = TREE_TYPE (exp); 7070 7071 if (!INTEGRAL_TYPE_P (orig_type)) 7072 { 7073 if (orig_type != error_mark_node) 7074 { 7075 error ("switch quantity not an integer"); 7076 orig_type = error_mark_node; 7077 } 7078 exp = integer_zero_node; 7079 } 7080 else 7081 { 7082 tree type = TYPE_MAIN_VARIANT (orig_type); 7083 7084 if (!in_system_header 7085 && (type == long_integer_type_node 7086 || type == long_unsigned_type_node)) 7087 warning (OPT_Wtraditional, "%<long%> switch expression not " 7088 "converted to %<int%> in ISO C"); 7089 7090 exp = default_conversion (exp); 7091 } 7092 } 7093 7094 /* Add this new SWITCH_EXPR to the stack. */ 7095 cs = XNEW (struct c_switch); 7096 cs->switch_expr = build3 (SWITCH_EXPR, orig_type, exp, NULL_TREE, NULL_TREE); 7097 cs->orig_type = orig_type; 7098 cs->cases = splay_tree_new (case_compare, NULL, NULL); 7099 cs->blocked_stmt_expr = 0; 7100 cs->blocked_vm = 0; 7101 cs->next = c_switch_stack; 7102 c_switch_stack = cs; 7103 7104 return add_stmt (cs->switch_expr); 7105} 7106 7107/* Process a case label. */ 7108 7109tree 7110do_case (tree low_value, tree high_value) 7111{ 7112 tree label = NULL_TREE; 7113 7114 if (c_switch_stack && !c_switch_stack->blocked_stmt_expr 7115 && !c_switch_stack->blocked_vm) 7116 { 7117 label = c_add_case_label (c_switch_stack->cases, 7118 SWITCH_COND (c_switch_stack->switch_expr), 7119 c_switch_stack->orig_type, 7120 low_value, high_value); 7121 if (label == error_mark_node) 7122 label = NULL_TREE; 7123 } 7124 else if (c_switch_stack && c_switch_stack->blocked_stmt_expr) 7125 { 7126 if (low_value) 7127 error ("case label in statement expression not containing " 7128 "enclosing switch statement"); 7129 else 7130 error ("%<default%> label in statement expression not containing " 7131 "enclosing switch statement"); 7132 } 7133 else if (c_switch_stack && c_switch_stack->blocked_vm) 7134 { 7135 if (low_value) 7136 error ("case label in scope of identifier with variably modified " 7137 "type not containing enclosing switch statement"); 7138 else 7139 error ("%<default%> label in scope of identifier with variably " 7140 "modified type not containing enclosing switch statement"); 7141 } 7142 else if (low_value) 7143 error ("case label not within a switch statement"); 7144 else 7145 error ("%<default%> label not within a switch statement"); 7146 7147 return label; 7148} 7149 7150/* Finish the switch statement. */ 7151 7152void 7153c_finish_case (tree body) 7154{ 7155 struct c_switch *cs = c_switch_stack; 7156 location_t switch_location; 7157 7158 SWITCH_BODY (cs->switch_expr) = body; 7159 7160 /* We must not be within a statement expression nested in the switch 7161 at this point; we might, however, be within the scope of an 7162 identifier with variably modified type nested in the switch. */ 7163 gcc_assert (!cs->blocked_stmt_expr); 7164 7165 /* Emit warnings as needed. */ 7166 if (EXPR_HAS_LOCATION (cs->switch_expr)) 7167 switch_location = EXPR_LOCATION (cs->switch_expr); 7168 else 7169 switch_location = input_location; 7170 c_do_switch_warnings (cs->cases, switch_location, 7171 TREE_TYPE (cs->switch_expr), 7172 SWITCH_COND (cs->switch_expr)); 7173 7174 /* Pop the stack. */ 7175 c_switch_stack = cs->next; 7176 splay_tree_delete (cs->cases); 7177 XDELETE (cs); 7178} 7179 7180/* Emit an if statement. IF_LOCUS is the location of the 'if'. COND, 7181 THEN_BLOCK and ELSE_BLOCK are expressions to be used; ELSE_BLOCK 7182 may be null. NESTED_IF is true if THEN_BLOCK contains another IF 7183 statement, and was not surrounded with parenthesis. */ 7184 7185void 7186c_finish_if_stmt (location_t if_locus, tree cond, tree then_block, 7187 tree else_block, bool nested_if) 7188{ 7189 tree stmt; 7190 7191 /* Diagnose an ambiguous else if if-then-else is nested inside if-then. */ 7192 if (warn_parentheses && nested_if && else_block == NULL) 7193 { 7194 tree inner_if = then_block; 7195 7196 /* We know from the grammar productions that there is an IF nested 7197 within THEN_BLOCK. Due to labels and c99 conditional declarations, 7198 it might not be exactly THEN_BLOCK, but should be the last 7199 non-container statement within. */ 7200 while (1) 7201 switch (TREE_CODE (inner_if)) 7202 { 7203 case COND_EXPR: 7204 goto found; 7205 case BIND_EXPR: 7206 inner_if = BIND_EXPR_BODY (inner_if); 7207 break; 7208 case STATEMENT_LIST: 7209 inner_if = expr_last (then_block); 7210 break; 7211 case TRY_FINALLY_EXPR: 7212 case TRY_CATCH_EXPR: 7213 inner_if = TREE_OPERAND (inner_if, 0); 7214 break; 7215 default: 7216 gcc_unreachable (); 7217 } 7218 found: 7219 7220 if (COND_EXPR_ELSE (inner_if)) 7221 warning (OPT_Wparentheses, 7222 "%Hsuggest explicit braces to avoid ambiguous %<else%>", 7223 &if_locus); 7224 } 7225 7226 empty_body_warning (then_block, else_block); 7227 7228 stmt = build3 (COND_EXPR, void_type_node, cond, then_block, else_block); 7229 SET_EXPR_LOCATION (stmt, if_locus); 7230 add_stmt (stmt); 7231} 7232 7233/* Emit a general-purpose loop construct. START_LOCUS is the location of 7234 the beginning of the loop. COND is the loop condition. COND_IS_FIRST 7235 is false for DO loops. INCR is the FOR increment expression. BODY is 7236 the statement controlled by the loop. BLAB is the break label. CLAB is 7237 the continue label. Everything is allowed to be NULL. */ 7238 7239void 7240c_finish_loop (location_t start_locus, tree cond, tree incr, tree body, 7241 tree blab, tree clab, bool cond_is_first) 7242{ 7243 tree entry = NULL, exit = NULL, t; 7244 7245 /* If the condition is zero don't generate a loop construct. */ 7246 if (cond && integer_zerop (cond)) 7247 { 7248 if (cond_is_first) 7249 { 7250 t = build_and_jump (&blab); 7251 SET_EXPR_LOCATION (t, start_locus); 7252 add_stmt (t); 7253 } 7254 } 7255 else 7256 { 7257 tree top = build1 (LABEL_EXPR, void_type_node, NULL_TREE); 7258 7259 /* If we have an exit condition, then we build an IF with gotos either 7260 out of the loop, or to the top of it. If there's no exit condition, 7261 then we just build a jump back to the top. */ 7262 exit = build_and_jump (&LABEL_EXPR_LABEL (top)); 7263 7264 if (cond && !integer_nonzerop (cond)) 7265 { 7266 /* Canonicalize the loop condition to the end. This means 7267 generating a branch to the loop condition. Reuse the 7268 continue label, if possible. */ 7269 if (cond_is_first) 7270 { 7271 if (incr || !clab) 7272 { 7273 entry = build1 (LABEL_EXPR, void_type_node, NULL_TREE); 7274 t = build_and_jump (&LABEL_EXPR_LABEL (entry)); 7275 } 7276 else 7277 t = build1 (GOTO_EXPR, void_type_node, clab); 7278 SET_EXPR_LOCATION (t, start_locus); 7279 add_stmt (t); 7280 } 7281 7282 t = build_and_jump (&blab); 7283 exit = fold_build3 (COND_EXPR, void_type_node, cond, exit, t); 7284 if (cond_is_first) 7285 SET_EXPR_LOCATION (exit, start_locus); 7286 else 7287 SET_EXPR_LOCATION (exit, input_location); 7288 } 7289 7290 add_stmt (top); 7291 } 7292 7293 if (body) 7294 add_stmt (body); 7295 if (clab) 7296 add_stmt (build1 (LABEL_EXPR, void_type_node, clab)); 7297 if (incr) 7298 add_stmt (incr); 7299 if (entry) 7300 add_stmt (entry); 7301 if (exit) 7302 add_stmt (exit); 7303 if (blab) 7304 add_stmt (build1 (LABEL_EXPR, void_type_node, blab)); 7305} 7306 7307tree 7308c_finish_bc_stmt (tree *label_p, bool is_break) 7309{ 7310 bool skip; 7311 tree label = *label_p; 7312 7313 /* In switch statements break is sometimes stylistically used after 7314 a return statement. This can lead to spurious warnings about 7315 control reaching the end of a non-void function when it is 7316 inlined. Note that we are calling block_may_fallthru with 7317 language specific tree nodes; this works because 7318 block_may_fallthru returns true when given something it does not 7319 understand. */ 7320 skip = !block_may_fallthru (cur_stmt_list); 7321 7322 if (!label) 7323 { 7324 if (!skip) 7325 *label_p = label = create_artificial_label (); 7326 } 7327 else if (TREE_CODE (label) == LABEL_DECL) 7328 ; 7329 else switch (TREE_INT_CST_LOW (label)) 7330 { 7331 case 0: 7332 if (is_break) 7333 error ("break statement not within loop or switch"); 7334 else 7335 error ("continue statement not within a loop"); 7336 return NULL_TREE; 7337 7338 case 1: 7339 gcc_assert (is_break); 7340 error ("break statement used with OpenMP for loop"); 7341 return NULL_TREE; 7342 7343 default: 7344 gcc_unreachable (); 7345 } 7346 7347 if (skip) 7348 return NULL_TREE; 7349 7350 return add_stmt (build1 (GOTO_EXPR, void_type_node, label)); 7351} 7352 7353/* A helper routine for c_process_expr_stmt and c_finish_stmt_expr. */ 7354 7355static void 7356emit_side_effect_warnings (tree expr) 7357{ 7358 if (expr == error_mark_node) 7359 ; 7360 else if (!TREE_SIDE_EFFECTS (expr)) 7361 { 7362 if (!VOID_TYPE_P (TREE_TYPE (expr)) && !TREE_NO_WARNING (expr)) 7363 warning (0, "%Hstatement with no effect", 7364 EXPR_HAS_LOCATION (expr) ? EXPR_LOCUS (expr) : &input_location); 7365 } 7366 else if (warn_unused_value) 7367 warn_if_unused_value (expr, input_location); 7368} 7369 7370/* Process an expression as if it were a complete statement. Emit 7371 diagnostics, but do not call ADD_STMT. */ 7372 7373tree 7374c_process_expr_stmt (tree expr) 7375{ 7376 if (!expr) 7377 return NULL_TREE; 7378 7379 if (warn_sequence_point) 7380 verify_sequence_points (expr); 7381 7382 if (TREE_TYPE (expr) != error_mark_node 7383 && !COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (expr)) 7384 && TREE_CODE (TREE_TYPE (expr)) != ARRAY_TYPE) 7385 error ("expression statement has incomplete type"); 7386 7387 /* If we're not processing a statement expression, warn about unused values. 7388 Warnings for statement expressions will be emitted later, once we figure 7389 out which is the result. */ 7390 if (!STATEMENT_LIST_STMT_EXPR (cur_stmt_list) 7391 && (extra_warnings || warn_unused_value)) 7392 emit_side_effect_warnings (expr); 7393 7394 /* If the expression is not of a type to which we cannot assign a line 7395 number, wrap the thing in a no-op NOP_EXPR. */ 7396 if (DECL_P (expr) || CONSTANT_CLASS_P (expr)) 7397 expr = build1 (NOP_EXPR, TREE_TYPE (expr), expr); 7398 7399 if (EXPR_P (expr)) 7400 SET_EXPR_LOCATION (expr, input_location); 7401 7402 return expr; 7403} 7404 7405/* Emit an expression as a statement. */ 7406 7407tree 7408c_finish_expr_stmt (tree expr) 7409{ 7410 if (expr) 7411 return add_stmt (c_process_expr_stmt (expr)); 7412 else 7413 return NULL; 7414} 7415 7416/* Do the opposite and emit a statement as an expression. To begin, 7417 create a new binding level and return it. */ 7418 7419tree 7420c_begin_stmt_expr (void) 7421{ 7422 tree ret; 7423 struct c_label_context_se *nstack; 7424 struct c_label_list *glist; 7425 7426 /* We must force a BLOCK for this level so that, if it is not expanded 7427 later, there is a way to turn off the entire subtree of blocks that 7428 are contained in it. */ 7429 keep_next_level (); 7430 ret = c_begin_compound_stmt (true); 7431 if (c_switch_stack) 7432 { 7433 c_switch_stack->blocked_stmt_expr++; 7434 gcc_assert (c_switch_stack->blocked_stmt_expr != 0); 7435 } 7436 for (glist = label_context_stack_se->labels_used; 7437 glist != NULL; 7438 glist = glist->next) 7439 { 7440 C_DECL_UNDEFINABLE_STMT_EXPR (glist->label) = 1; 7441 } 7442 nstack = XOBNEW (&parser_obstack, struct c_label_context_se); 7443 nstack->labels_def = NULL; 7444 nstack->labels_used = NULL; 7445 nstack->next = label_context_stack_se; 7446 label_context_stack_se = nstack; 7447 7448 /* Mark the current statement list as belonging to a statement list. */ 7449 STATEMENT_LIST_STMT_EXPR (ret) = 1; 7450 7451 return ret; 7452} 7453 7454tree 7455c_finish_stmt_expr (tree body) 7456{ 7457 tree last, type, tmp, val; 7458 tree *last_p; 7459 struct c_label_list *dlist, *glist, *glist_prev = NULL; 7460 7461 body = c_end_compound_stmt (body, true); 7462 if (c_switch_stack) 7463 { 7464 gcc_assert (c_switch_stack->blocked_stmt_expr != 0); 7465 c_switch_stack->blocked_stmt_expr--; 7466 } 7467 /* It is no longer possible to jump to labels defined within this 7468 statement expression. */ 7469 for (dlist = label_context_stack_se->labels_def; 7470 dlist != NULL; 7471 dlist = dlist->next) 7472 { 7473 C_DECL_UNJUMPABLE_STMT_EXPR (dlist->label) = 1; 7474 } 7475 /* It is again possible to define labels with a goto just outside 7476 this statement expression. */ 7477 for (glist = label_context_stack_se->next->labels_used; 7478 glist != NULL; 7479 glist = glist->next) 7480 { 7481 C_DECL_UNDEFINABLE_STMT_EXPR (glist->label) = 0; 7482 glist_prev = glist; 7483 } 7484 if (glist_prev != NULL) 7485 glist_prev->next = label_context_stack_se->labels_used; 7486 else 7487 label_context_stack_se->next->labels_used 7488 = label_context_stack_se->labels_used; 7489 label_context_stack_se = label_context_stack_se->next; 7490 7491 /* Locate the last statement in BODY. See c_end_compound_stmt 7492 about always returning a BIND_EXPR. */ 7493 last_p = &BIND_EXPR_BODY (body); 7494 last = BIND_EXPR_BODY (body); 7495 7496 continue_searching: 7497 if (TREE_CODE (last) == STATEMENT_LIST) 7498 { 7499 tree_stmt_iterator i; 7500 7501 /* This can happen with degenerate cases like ({ }). No value. */ 7502 if (!TREE_SIDE_EFFECTS (last)) 7503 return body; 7504 7505 /* If we're supposed to generate side effects warnings, process 7506 all of the statements except the last. */ 7507 if (extra_warnings || warn_unused_value) 7508 { 7509 for (i = tsi_start (last); !tsi_one_before_end_p (i); tsi_next (&i)) 7510 emit_side_effect_warnings (tsi_stmt (i)); 7511 } 7512 else 7513 i = tsi_last (last); 7514 last_p = tsi_stmt_ptr (i); 7515 last = *last_p; 7516 } 7517 7518 /* If the end of the list is exception related, then the list was split 7519 by a call to push_cleanup. Continue searching. */ 7520 if (TREE_CODE (last) == TRY_FINALLY_EXPR 7521 || TREE_CODE (last) == TRY_CATCH_EXPR) 7522 { 7523 last_p = &TREE_OPERAND (last, 0); 7524 last = *last_p; 7525 goto continue_searching; 7526 } 7527 7528 /* In the case that the BIND_EXPR is not necessary, return the 7529 expression out from inside it. */ 7530 if (last == error_mark_node 7531 || (last == BIND_EXPR_BODY (body) 7532 && BIND_EXPR_VARS (body) == NULL)) 7533 { 7534 /* Do not warn if the return value of a statement expression is 7535 unused. */ 7536 if (EXPR_P (last)) 7537 TREE_NO_WARNING (last) = 1; 7538 return last; 7539 } 7540 7541 /* Extract the type of said expression. */ 7542 type = TREE_TYPE (last); 7543 7544 /* If we're not returning a value at all, then the BIND_EXPR that 7545 we already have is a fine expression to return. */ 7546 if (!type || VOID_TYPE_P (type)) 7547 return body; 7548 7549 /* Now that we've located the expression containing the value, it seems 7550 silly to make voidify_wrapper_expr repeat the process. Create a 7551 temporary of the appropriate type and stick it in a TARGET_EXPR. */ 7552 tmp = create_tmp_var_raw (type, NULL); 7553 7554 /* Unwrap a no-op NOP_EXPR as added by c_finish_expr_stmt. This avoids 7555 tree_expr_nonnegative_p giving up immediately. */ 7556 val = last; 7557 if (TREE_CODE (val) == NOP_EXPR 7558 && TREE_TYPE (val) == TREE_TYPE (TREE_OPERAND (val, 0))) 7559 val = TREE_OPERAND (val, 0); 7560 7561 *last_p = build2 (MODIFY_EXPR, void_type_node, tmp, val); 7562 SET_EXPR_LOCUS (*last_p, EXPR_LOCUS (last)); 7563 7564 return build4 (TARGET_EXPR, type, tmp, body, NULL_TREE, NULL_TREE); 7565} 7566 7567/* Begin the scope of an identifier of variably modified type, scope 7568 number SCOPE. Jumping from outside this scope to inside it is not 7569 permitted. */ 7570 7571void 7572c_begin_vm_scope (unsigned int scope) 7573{ 7574 struct c_label_context_vm *nstack; 7575 struct c_label_list *glist; 7576 7577 gcc_assert (scope > 0); 7578 7579 /* At file_scope, we don't have to do any processing. */ 7580 if (label_context_stack_vm == NULL) 7581 return; 7582 7583 if (c_switch_stack && !c_switch_stack->blocked_vm) 7584 c_switch_stack->blocked_vm = scope; 7585 for (glist = label_context_stack_vm->labels_used; 7586 glist != NULL; 7587 glist = glist->next) 7588 { 7589 C_DECL_UNDEFINABLE_VM (glist->label) = 1; 7590 } 7591 nstack = XOBNEW (&parser_obstack, struct c_label_context_vm); 7592 nstack->labels_def = NULL; 7593 nstack->labels_used = NULL; 7594 nstack->scope = scope; 7595 nstack->next = label_context_stack_vm; 7596 label_context_stack_vm = nstack; 7597} 7598 7599/* End a scope which may contain identifiers of variably modified 7600 type, scope number SCOPE. */ 7601 7602void 7603c_end_vm_scope (unsigned int scope) 7604{ 7605 if (label_context_stack_vm == NULL) 7606 return; 7607 if (c_switch_stack && c_switch_stack->blocked_vm == scope) 7608 c_switch_stack->blocked_vm = 0; 7609 /* We may have a number of nested scopes of identifiers with 7610 variably modified type, all at this depth. Pop each in turn. */ 7611 while (label_context_stack_vm->scope == scope) 7612 { 7613 struct c_label_list *dlist, *glist, *glist_prev = NULL; 7614 7615 /* It is no longer possible to jump to labels defined within this 7616 scope. */ 7617 for (dlist = label_context_stack_vm->labels_def; 7618 dlist != NULL; 7619 dlist = dlist->next) 7620 { 7621 C_DECL_UNJUMPABLE_VM (dlist->label) = 1; 7622 } 7623 /* It is again possible to define labels with a goto just outside 7624 this scope. */ 7625 for (glist = label_context_stack_vm->next->labels_used; 7626 glist != NULL; 7627 glist = glist->next) 7628 { 7629 C_DECL_UNDEFINABLE_VM (glist->label) = 0; 7630 glist_prev = glist; 7631 } 7632 if (glist_prev != NULL) 7633 glist_prev->next = label_context_stack_vm->labels_used; 7634 else 7635 label_context_stack_vm->next->labels_used 7636 = label_context_stack_vm->labels_used; 7637 label_context_stack_vm = label_context_stack_vm->next; 7638 } 7639} 7640 7641/* Begin and end compound statements. This is as simple as pushing 7642 and popping new statement lists from the tree. */ 7643 7644tree 7645c_begin_compound_stmt (bool do_scope) 7646{ 7647 tree stmt = push_stmt_list (); 7648 if (do_scope) 7649 push_scope (); 7650 return stmt; 7651} 7652 7653tree 7654c_end_compound_stmt (tree stmt, bool do_scope) 7655{ 7656 tree block = NULL; 7657 7658 if (do_scope) 7659 { 7660 if (c_dialect_objc ()) 7661 objc_clear_super_receiver (); 7662 block = pop_scope (); 7663 } 7664 7665 stmt = pop_stmt_list (stmt); 7666 stmt = c_build_bind_expr (block, stmt); 7667 7668 /* If this compound statement is nested immediately inside a statement 7669 expression, then force a BIND_EXPR to be created. Otherwise we'll 7670 do the wrong thing for ({ { 1; } }) or ({ 1; { } }). In particular, 7671 STATEMENT_LISTs merge, and thus we can lose track of what statement 7672 was really last. */ 7673 if (cur_stmt_list 7674 && STATEMENT_LIST_STMT_EXPR (cur_stmt_list) 7675 && TREE_CODE (stmt) != BIND_EXPR) 7676 { 7677 stmt = build3 (BIND_EXPR, void_type_node, NULL, stmt, NULL); 7678 TREE_SIDE_EFFECTS (stmt) = 1; 7679 } 7680 7681 return stmt; 7682} 7683 7684/* Queue a cleanup. CLEANUP is an expression/statement to be executed 7685 when the current scope is exited. EH_ONLY is true when this is not 7686 meant to apply to normal control flow transfer. */ 7687 7688void 7689push_cleanup (tree ARG_UNUSED (decl), tree cleanup, bool eh_only) 7690{ 7691 enum tree_code code; 7692 tree stmt, list; 7693 bool stmt_expr; 7694 7695 code = eh_only ? TRY_CATCH_EXPR : TRY_FINALLY_EXPR; 7696 stmt = build_stmt (code, NULL, cleanup); 7697 add_stmt (stmt); 7698 stmt_expr = STATEMENT_LIST_STMT_EXPR (cur_stmt_list); 7699 list = push_stmt_list (); 7700 TREE_OPERAND (stmt, 0) = list; 7701 STATEMENT_LIST_STMT_EXPR (list) = stmt_expr; 7702} 7703 7704/* Build a binary-operation expression without default conversions. 7705 CODE is the kind of expression to build. 7706 This function differs from `build' in several ways: 7707 the data type of the result is computed and recorded in it, 7708 warnings are generated if arg data types are invalid, 7709 special handling for addition and subtraction of pointers is known, 7710 and some optimization is done (operations on narrow ints 7711 are done in the narrower type when that gives the same result). 7712 Constant folding is also done before the result is returned. 7713 7714 Note that the operands will never have enumeral types, or function 7715 or array types, because either they will have the default conversions 7716 performed or they have both just been converted to some other type in which 7717 the arithmetic is to be done. */ 7718 7719tree 7720build_binary_op (enum tree_code code, tree orig_op0, tree orig_op1, 7721 int convert_p) 7722{ 7723 tree type0, type1; 7724 enum tree_code code0, code1; 7725 tree op0, op1; 7726 const char *invalid_op_diag; 7727 7728 /* Expression code to give to the expression when it is built. 7729 Normally this is CODE, which is what the caller asked for, 7730 but in some special cases we change it. */ 7731 enum tree_code resultcode = code; 7732 7733 /* Data type in which the computation is to be performed. 7734 In the simplest cases this is the common type of the arguments. */ 7735 tree result_type = NULL; 7736 7737 /* Nonzero means operands have already been type-converted 7738 in whatever way is necessary. 7739 Zero means they need to be converted to RESULT_TYPE. */ 7740 int converted = 0; 7741 7742 /* Nonzero means create the expression with this type, rather than 7743 RESULT_TYPE. */ 7744 tree build_type = 0; 7745 7746 /* Nonzero means after finally constructing the expression 7747 convert it to this type. */ 7748 tree final_type = 0; 7749 7750 /* Nonzero if this is an operation like MIN or MAX which can 7751 safely be computed in short if both args are promoted shorts. 7752 Also implies COMMON. 7753 -1 indicates a bitwise operation; this makes a difference 7754 in the exact conditions for when it is safe to do the operation 7755 in a narrower mode. */ 7756 int shorten = 0; 7757 7758 /* Nonzero if this is a comparison operation; 7759 if both args are promoted shorts, compare the original shorts. 7760 Also implies COMMON. */ 7761 int short_compare = 0; 7762 7763 /* Nonzero if this is a right-shift operation, which can be computed on the 7764 original short and then promoted if the operand is a promoted short. */ 7765 int short_shift = 0; 7766 7767 /* Nonzero means set RESULT_TYPE to the common type of the args. */ 7768 int common = 0; 7769 7770 /* True means types are compatible as far as ObjC is concerned. */ 7771 bool objc_ok; 7772 7773 if (convert_p) 7774 { 7775 op0 = default_conversion (orig_op0); 7776 op1 = default_conversion (orig_op1); 7777 } 7778 else 7779 { 7780 op0 = orig_op0; 7781 op1 = orig_op1; 7782 } 7783 7784 type0 = TREE_TYPE (op0); 7785 type1 = TREE_TYPE (op1); 7786 7787 /* The expression codes of the data types of the arguments tell us 7788 whether the arguments are integers, floating, pointers, etc. */ 7789 code0 = TREE_CODE (type0); 7790 code1 = TREE_CODE (type1); 7791 7792 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */ 7793 STRIP_TYPE_NOPS (op0); 7794 STRIP_TYPE_NOPS (op1); 7795 7796 /* If an error was already reported for one of the arguments, 7797 avoid reporting another error. */ 7798 7799 if (code0 == ERROR_MARK || code1 == ERROR_MARK) 7800 return error_mark_node; 7801 7802 if ((invalid_op_diag 7803 = targetm.invalid_binary_op (code, type0, type1))) 7804 { 7805 error (invalid_op_diag); 7806 return error_mark_node; 7807 } 7808 7809 objc_ok = objc_compare_types (type0, type1, -3, NULL_TREE); 7810 7811 switch (code) 7812 { 7813 case PLUS_EXPR: 7814 /* Handle the pointer + int case. */ 7815 if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE) 7816 return pointer_int_sum (PLUS_EXPR, op0, op1); 7817 else if (code1 == POINTER_TYPE && code0 == INTEGER_TYPE) 7818 return pointer_int_sum (PLUS_EXPR, op1, op0); 7819 else 7820 common = 1; 7821 break; 7822 7823 case MINUS_EXPR: 7824 /* Subtraction of two similar pointers. 7825 We must subtract them as integers, then divide by object size. */ 7826 if (code0 == POINTER_TYPE && code1 == POINTER_TYPE 7827 && comp_target_types (type0, type1)) 7828 return pointer_diff (op0, op1); 7829 /* Handle pointer minus int. Just like pointer plus int. */ 7830 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE) 7831 return pointer_int_sum (MINUS_EXPR, op0, op1); 7832 else 7833 common = 1; 7834 break; 7835 7836 case MULT_EXPR: 7837 common = 1; 7838 break; 7839 7840 case TRUNC_DIV_EXPR: 7841 case CEIL_DIV_EXPR: 7842 case FLOOR_DIV_EXPR: 7843 case ROUND_DIV_EXPR: 7844 case EXACT_DIV_EXPR: 7845 /* Floating point division by zero is a legitimate way to obtain 7846 infinities and NaNs. */ 7847 if (skip_evaluation == 0 && integer_zerop (op1)) 7848 warning (OPT_Wdiv_by_zero, "division by zero"); 7849 7850 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE 7851 || code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE) 7852 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE 7853 || code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE)) 7854 { 7855 enum tree_code tcode0 = code0, tcode1 = code1; 7856 7857 if (code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE) 7858 tcode0 = TREE_CODE (TREE_TYPE (TREE_TYPE (op0))); 7859 if (code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE) 7860 tcode1 = TREE_CODE (TREE_TYPE (TREE_TYPE (op1))); 7861 7862 if (!(tcode0 == INTEGER_TYPE && tcode1 == INTEGER_TYPE)) 7863 resultcode = RDIV_EXPR; 7864 else 7865 /* Although it would be tempting to shorten always here, that 7866 loses on some targets, since the modulo instruction is 7867 undefined if the quotient can't be represented in the 7868 computation mode. We shorten only if unsigned or if 7869 dividing by something we know != -1. */ 7870 shorten = (TYPE_UNSIGNED (TREE_TYPE (orig_op0)) 7871 || (TREE_CODE (op1) == INTEGER_CST 7872 && !integer_all_onesp (op1))); 7873 common = 1; 7874 } 7875 break; 7876 7877 case BIT_AND_EXPR: 7878 case BIT_IOR_EXPR: 7879 case BIT_XOR_EXPR: 7880 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE) 7881 shorten = -1; 7882 else if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE) 7883 common = 1; 7884 break; 7885 7886 case TRUNC_MOD_EXPR: 7887 case FLOOR_MOD_EXPR: 7888 if (skip_evaluation == 0 && integer_zerop (op1)) 7889 warning (OPT_Wdiv_by_zero, "division by zero"); 7890 7891 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE) 7892 { 7893 /* Although it would be tempting to shorten always here, that loses 7894 on some targets, since the modulo instruction is undefined if the 7895 quotient can't be represented in the computation mode. We shorten 7896 only if unsigned or if dividing by something we know != -1. */ 7897 shorten = (TYPE_UNSIGNED (TREE_TYPE (orig_op0)) 7898 || (TREE_CODE (op1) == INTEGER_CST 7899 && !integer_all_onesp (op1))); 7900 common = 1; 7901 } 7902 break; 7903 7904 case TRUTH_ANDIF_EXPR: 7905 case TRUTH_ORIF_EXPR: 7906 case TRUTH_AND_EXPR: 7907 case TRUTH_OR_EXPR: 7908 case TRUTH_XOR_EXPR: 7909 if ((code0 == INTEGER_TYPE || code0 == POINTER_TYPE 7910 || code0 == REAL_TYPE || code0 == COMPLEX_TYPE) 7911 && (code1 == INTEGER_TYPE || code1 == POINTER_TYPE 7912 || code1 == REAL_TYPE || code1 == COMPLEX_TYPE)) 7913 { 7914 /* Result of these operations is always an int, 7915 but that does not mean the operands should be 7916 converted to ints! */ 7917 result_type = integer_type_node; 7918 op0 = c_common_truthvalue_conversion (op0); 7919 op1 = c_common_truthvalue_conversion (op1); 7920 converted = 1; 7921 } 7922 break; 7923 7924 /* Shift operations: result has same type as first operand; 7925 always convert second operand to int. 7926 Also set SHORT_SHIFT if shifting rightward. */ 7927 7928 case RSHIFT_EXPR: 7929 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE) 7930 { 7931 if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0) 7932 { 7933 if (tree_int_cst_sgn (op1) < 0) 7934 warning (0, "right shift count is negative"); 7935 else 7936 { 7937 if (!integer_zerop (op1)) 7938 short_shift = 1; 7939 7940 if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0) 7941 warning (0, "right shift count >= width of type"); 7942 } 7943 } 7944 7945 /* Use the type of the value to be shifted. */ 7946 result_type = type0; 7947 /* Convert the shift-count to an integer, regardless of size 7948 of value being shifted. */ 7949 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node) 7950 op1 = convert (integer_type_node, op1); 7951 /* Avoid converting op1 to result_type later. */ 7952 converted = 1; 7953 } 7954 break; 7955 7956 case LSHIFT_EXPR: 7957 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE) 7958 { 7959 if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0) 7960 { 7961 if (tree_int_cst_sgn (op1) < 0) 7962 warning (0, "left shift count is negative"); 7963 7964 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0) 7965 warning (0, "left shift count >= width of type"); 7966 } 7967 7968 /* Use the type of the value to be shifted. */ 7969 result_type = type0; 7970 /* Convert the shift-count to an integer, regardless of size 7971 of value being shifted. */ 7972 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node) 7973 op1 = convert (integer_type_node, op1); 7974 /* Avoid converting op1 to result_type later. */ 7975 converted = 1; 7976 } 7977 break; 7978 7979 case EQ_EXPR: 7980 case NE_EXPR: 7981 if (code0 == REAL_TYPE || code1 == REAL_TYPE) 7982 warning (OPT_Wfloat_equal, 7983 "comparing floating point with == or != is unsafe"); 7984 /* Result of comparison is always int, 7985 but don't convert the args to int! */ 7986 build_type = integer_type_node; 7987 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE 7988 || code0 == COMPLEX_TYPE) 7989 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE 7990 || code1 == COMPLEX_TYPE)) 7991 short_compare = 1; 7992 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE) 7993 { 7994 tree tt0 = TREE_TYPE (type0); 7995 tree tt1 = TREE_TYPE (type1); 7996 /* Anything compares with void *. void * compares with anything. 7997 Otherwise, the targets must be compatible 7998 and both must be object or both incomplete. */ 7999 if (comp_target_types (type0, type1)) 8000 result_type = common_pointer_type (type0, type1); 8001 else if (VOID_TYPE_P (tt0)) 8002 { 8003 /* op0 != orig_op0 detects the case of something 8004 whose value is 0 but which isn't a valid null ptr const. */ 8005 if (pedantic && !null_pointer_constant_p (orig_op0) 8006 && TREE_CODE (tt1) == FUNCTION_TYPE) 8007 pedwarn ("ISO C forbids comparison of %<void *%>" 8008 " with function pointer"); 8009 } 8010 else if (VOID_TYPE_P (tt1)) 8011 { 8012 if (pedantic && !null_pointer_constant_p (orig_op1) 8013 && TREE_CODE (tt0) == FUNCTION_TYPE) 8014 pedwarn ("ISO C forbids comparison of %<void *%>" 8015 " with function pointer"); 8016 } 8017 else 8018 /* Avoid warning about the volatile ObjC EH puts on decls. */ 8019 if (!objc_ok) 8020 pedwarn ("comparison of distinct pointer types lacks a cast"); 8021 8022 if (result_type == NULL_TREE) 8023 result_type = ptr_type_node; 8024 } 8025 else if (code0 == POINTER_TYPE && null_pointer_constant_p (orig_op1)) 8026 { 8027 if (TREE_CODE (op0) == ADDR_EXPR 8028 && DECL_P (TREE_OPERAND (op0, 0)) 8029 && (TREE_CODE (TREE_OPERAND (op0, 0)) == PARM_DECL 8030 || TREE_CODE (TREE_OPERAND (op0, 0)) == LABEL_DECL 8031 || !DECL_WEAK (TREE_OPERAND (op0, 0)))) 8032 warning (OPT_Waddress, "the address of %qD will never be NULL", 8033 TREE_OPERAND (op0, 0)); 8034 result_type = type0; 8035 } 8036 else if (code1 == POINTER_TYPE && null_pointer_constant_p (orig_op0)) 8037 { 8038 if (TREE_CODE (op1) == ADDR_EXPR 8039 && DECL_P (TREE_OPERAND (op1, 0)) 8040 && (TREE_CODE (TREE_OPERAND (op1, 0)) == PARM_DECL 8041 || TREE_CODE (TREE_OPERAND (op1, 0)) == LABEL_DECL 8042 || !DECL_WEAK (TREE_OPERAND (op1, 0)))) 8043 warning (OPT_Waddress, "the address of %qD will never be NULL", 8044 TREE_OPERAND (op1, 0)); 8045 result_type = type1; 8046 } 8047 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE) 8048 { 8049 result_type = type0; 8050 pedwarn ("comparison between pointer and integer"); 8051 } 8052 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE) 8053 { 8054 result_type = type1; 8055 pedwarn ("comparison between pointer and integer"); 8056 } 8057 break; 8058 8059 case LE_EXPR: 8060 case GE_EXPR: 8061 case LT_EXPR: 8062 case GT_EXPR: 8063 build_type = integer_type_node; 8064 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE) 8065 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE)) 8066 short_compare = 1; 8067 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE) 8068 { 8069 if (comp_target_types (type0, type1)) 8070 { 8071 result_type = common_pointer_type (type0, type1); 8072 if (!COMPLETE_TYPE_P (TREE_TYPE (type0)) 8073 != !COMPLETE_TYPE_P (TREE_TYPE (type1))) 8074 pedwarn ("comparison of complete and incomplete pointers"); 8075 else if (pedantic 8076 && TREE_CODE (TREE_TYPE (type0)) == FUNCTION_TYPE) 8077 pedwarn ("ISO C forbids ordered comparisons of pointers to functions"); 8078 } 8079 else 8080 { 8081 result_type = ptr_type_node; 8082 pedwarn ("comparison of distinct pointer types lacks a cast"); 8083 } 8084 } 8085 else if (code0 == POINTER_TYPE && null_pointer_constant_p (orig_op1)) 8086 { 8087 result_type = type0; 8088 if (pedantic || extra_warnings) 8089 pedwarn ("ordered comparison of pointer with integer zero"); 8090 } 8091 else if (code1 == POINTER_TYPE && null_pointer_constant_p (orig_op0)) 8092 { 8093 result_type = type1; 8094 if (pedantic) 8095 pedwarn ("ordered comparison of pointer with integer zero"); 8096 } 8097 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE) 8098 { 8099 result_type = type0; 8100 pedwarn ("comparison between pointer and integer"); 8101 } 8102 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE) 8103 { 8104 result_type = type1; 8105 pedwarn ("comparison between pointer and integer"); 8106 } 8107 break; 8108 8109 default: 8110 gcc_unreachable (); 8111 } 8112 8113 if (code0 == ERROR_MARK || code1 == ERROR_MARK) 8114 return error_mark_node; 8115 8116 if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE 8117 && (!tree_int_cst_equal (TYPE_SIZE (type0), TYPE_SIZE (type1)) 8118 || !same_scalar_type_ignoring_signedness (TREE_TYPE (type0), 8119 TREE_TYPE (type1)))) 8120 { 8121 binary_op_error (code); 8122 return error_mark_node; 8123 } 8124 8125 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE 8126 || code0 == VECTOR_TYPE) 8127 && 8128 (code1 == INTEGER_TYPE || code1 == REAL_TYPE || code1 == COMPLEX_TYPE 8129 || code1 == VECTOR_TYPE)) 8130 { 8131 int none_complex = (code0 != COMPLEX_TYPE && code1 != COMPLEX_TYPE); 8132 8133 if (shorten || common || short_compare) 8134 result_type = c_common_type (type0, type1); 8135 8136 /* For certain operations (which identify themselves by shorten != 0) 8137 if both args were extended from the same smaller type, 8138 do the arithmetic in that type and then extend. 8139 8140 shorten !=0 and !=1 indicates a bitwise operation. 8141 For them, this optimization is safe only if 8142 both args are zero-extended or both are sign-extended. 8143 Otherwise, we might change the result. 8144 Eg, (short)-1 | (unsigned short)-1 is (int)-1 8145 but calculated in (unsigned short) it would be (unsigned short)-1. */ 8146 8147 if (shorten && none_complex) 8148 { 8149 int unsigned0, unsigned1; 8150 tree arg0, arg1; 8151 int uns; 8152 tree type; 8153 8154 /* Cast OP0 and OP1 to RESULT_TYPE. Doing so prevents 8155 excessive narrowing when we call get_narrower below. For 8156 example, suppose that OP0 is of unsigned int extended 8157 from signed char and that RESULT_TYPE is long long int. 8158 If we explicitly cast OP0 to RESULT_TYPE, OP0 would look 8159 like 8160 8161 (long long int) (unsigned int) signed_char 8162 8163 which get_narrower would narrow down to 8164 8165 (unsigned int) signed char 8166 8167 If we do not cast OP0 first, get_narrower would return 8168 signed_char, which is inconsistent with the case of the 8169 explicit cast. */ 8170 op0 = convert (result_type, op0); 8171 op1 = convert (result_type, op1); 8172 8173 arg0 = get_narrower (op0, &unsigned0); 8174 arg1 = get_narrower (op1, &unsigned1); 8175 8176 /* UNS is 1 if the operation to be done is an unsigned one. */ 8177 uns = TYPE_UNSIGNED (result_type); 8178 8179 final_type = result_type; 8180 8181 /* Handle the case that OP0 (or OP1) does not *contain* a conversion 8182 but it *requires* conversion to FINAL_TYPE. */ 8183 8184 if ((TYPE_PRECISION (TREE_TYPE (op0)) 8185 == TYPE_PRECISION (TREE_TYPE (arg0))) 8186 && TREE_TYPE (op0) != final_type) 8187 unsigned0 = TYPE_UNSIGNED (TREE_TYPE (op0)); 8188 if ((TYPE_PRECISION (TREE_TYPE (op1)) 8189 == TYPE_PRECISION (TREE_TYPE (arg1))) 8190 && TREE_TYPE (op1) != final_type) 8191 unsigned1 = TYPE_UNSIGNED (TREE_TYPE (op1)); 8192 8193 /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */ 8194 8195 /* For bitwise operations, signedness of nominal type 8196 does not matter. Consider only how operands were extended. */ 8197 if (shorten == -1) 8198 uns = unsigned0; 8199 8200 /* Note that in all three cases below we refrain from optimizing 8201 an unsigned operation on sign-extended args. 8202 That would not be valid. */ 8203 8204 /* Both args variable: if both extended in same way 8205 from same width, do it in that width. 8206 Do it unsigned if args were zero-extended. */ 8207 if ((TYPE_PRECISION (TREE_TYPE (arg0)) 8208 < TYPE_PRECISION (result_type)) 8209 && (TYPE_PRECISION (TREE_TYPE (arg1)) 8210 == TYPE_PRECISION (TREE_TYPE (arg0))) 8211 && unsigned0 == unsigned1 8212 && (unsigned0 || !uns)) 8213 result_type 8214 = c_common_signed_or_unsigned_type 8215 (unsigned0, common_type (TREE_TYPE (arg0), TREE_TYPE (arg1))); 8216 else if (TREE_CODE (arg0) == INTEGER_CST 8217 && (unsigned1 || !uns) 8218 && (TYPE_PRECISION (TREE_TYPE (arg1)) 8219 < TYPE_PRECISION (result_type)) 8220 && (type 8221 = c_common_signed_or_unsigned_type (unsigned1, 8222 TREE_TYPE (arg1)), 8223 int_fits_type_p (arg0, type))) 8224 result_type = type; 8225 else if (TREE_CODE (arg1) == INTEGER_CST 8226 && (unsigned0 || !uns) 8227 && (TYPE_PRECISION (TREE_TYPE (arg0)) 8228 < TYPE_PRECISION (result_type)) 8229 && (type 8230 = c_common_signed_or_unsigned_type (unsigned0, 8231 TREE_TYPE (arg0)), 8232 int_fits_type_p (arg1, type))) 8233 result_type = type; 8234 } 8235 8236 /* Shifts can be shortened if shifting right. */ 8237 8238 if (short_shift) 8239 { 8240 int unsigned_arg; 8241 tree arg0 = get_narrower (op0, &unsigned_arg); 8242 8243 final_type = result_type; 8244 8245 if (arg0 == op0 && final_type == TREE_TYPE (op0)) 8246 unsigned_arg = TYPE_UNSIGNED (TREE_TYPE (op0)); 8247 8248 if (TYPE_PRECISION (TREE_TYPE (arg0)) < TYPE_PRECISION (result_type) 8249 /* We can shorten only if the shift count is less than the 8250 number of bits in the smaller type size. */ 8251 && compare_tree_int (op1, TYPE_PRECISION (TREE_TYPE (arg0))) < 0 8252 /* We cannot drop an unsigned shift after sign-extension. */ 8253 && (!TYPE_UNSIGNED (final_type) || unsigned_arg)) 8254 { 8255 /* Do an unsigned shift if the operand was zero-extended. */ 8256 result_type 8257 = c_common_signed_or_unsigned_type (unsigned_arg, 8258 TREE_TYPE (arg0)); 8259 /* Convert value-to-be-shifted to that type. */ 8260 if (TREE_TYPE (op0) != result_type) 8261 op0 = convert (result_type, op0); 8262 converted = 1; 8263 } 8264 } 8265 8266 /* Comparison operations are shortened too but differently. 8267 They identify themselves by setting short_compare = 1. */ 8268 8269 if (short_compare) 8270 { 8271 /* Don't write &op0, etc., because that would prevent op0 8272 from being kept in a register. 8273 Instead, make copies of the our local variables and 8274 pass the copies by reference, then copy them back afterward. */ 8275 tree xop0 = op0, xop1 = op1, xresult_type = result_type; 8276 enum tree_code xresultcode = resultcode; 8277 tree val 8278 = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode); 8279 8280 if (val != 0) 8281 return val; 8282 8283 op0 = xop0, op1 = xop1; 8284 converted = 1; 8285 resultcode = xresultcode; 8286 8287 if (warn_sign_compare && skip_evaluation == 0) 8288 { 8289 int op0_signed = !TYPE_UNSIGNED (TREE_TYPE (orig_op0)); 8290 int op1_signed = !TYPE_UNSIGNED (TREE_TYPE (orig_op1)); 8291 int unsignedp0, unsignedp1; 8292 tree primop0 = get_narrower (op0, &unsignedp0); 8293 tree primop1 = get_narrower (op1, &unsignedp1); 8294 8295 xop0 = orig_op0; 8296 xop1 = orig_op1; 8297 STRIP_TYPE_NOPS (xop0); 8298 STRIP_TYPE_NOPS (xop1); 8299 8300 /* Give warnings for comparisons between signed and unsigned 8301 quantities that may fail. 8302 8303 Do the checking based on the original operand trees, so that 8304 casts will be considered, but default promotions won't be. 8305 8306 Do not warn if the comparison is being done in a signed type, 8307 since the signed type will only be chosen if it can represent 8308 all the values of the unsigned type. */ 8309 if (!TYPE_UNSIGNED (result_type)) 8310 /* OK */; 8311 /* Do not warn if both operands are the same signedness. */ 8312 else if (op0_signed == op1_signed) 8313 /* OK */; 8314 else 8315 { 8316 tree sop, uop; 8317 bool ovf; 8318 8319 if (op0_signed) 8320 sop = xop0, uop = xop1; 8321 else 8322 sop = xop1, uop = xop0; 8323 8324 /* Do not warn if the signed quantity is an 8325 unsuffixed integer literal (or some static 8326 constant expression involving such literals or a 8327 conditional expression involving such literals) 8328 and it is non-negative. */ 8329 if (tree_expr_nonnegative_warnv_p (sop, &ovf)) 8330 /* OK */; 8331 /* Do not warn if the comparison is an equality operation, 8332 the unsigned quantity is an integral constant, and it 8333 would fit in the result if the result were signed. */ 8334 else if (TREE_CODE (uop) == INTEGER_CST 8335 && (resultcode == EQ_EXPR || resultcode == NE_EXPR) 8336 && int_fits_type_p 8337 (uop, c_common_signed_type (result_type))) 8338 /* OK */; 8339 /* Do not warn if the unsigned quantity is an enumeration 8340 constant and its maximum value would fit in the result 8341 if the result were signed. */ 8342 else if (TREE_CODE (uop) == INTEGER_CST 8343 && TREE_CODE (TREE_TYPE (uop)) == ENUMERAL_TYPE 8344 && int_fits_type_p 8345 (TYPE_MAX_VALUE (TREE_TYPE (uop)), 8346 c_common_signed_type (result_type))) 8347 /* OK */; 8348 else 8349 warning (0, "comparison between signed and unsigned"); 8350 } 8351 8352 /* Warn if two unsigned values are being compared in a size 8353 larger than their original size, and one (and only one) is the 8354 result of a `~' operator. This comparison will always fail. 8355 8356 Also warn if one operand is a constant, and the constant 8357 does not have all bits set that are set in the ~ operand 8358 when it is extended. */ 8359 8360 if ((TREE_CODE (primop0) == BIT_NOT_EXPR) 8361 != (TREE_CODE (primop1) == BIT_NOT_EXPR)) 8362 { 8363 if (TREE_CODE (primop0) == BIT_NOT_EXPR) 8364 primop0 = get_narrower (TREE_OPERAND (primop0, 0), 8365 &unsignedp0); 8366 else 8367 primop1 = get_narrower (TREE_OPERAND (primop1, 0), 8368 &unsignedp1); 8369 8370 if (host_integerp (primop0, 0) || host_integerp (primop1, 0)) 8371 { 8372 tree primop; 8373 HOST_WIDE_INT constant, mask; 8374 int unsignedp, bits; 8375 8376 if (host_integerp (primop0, 0)) 8377 { 8378 primop = primop1; 8379 unsignedp = unsignedp1; 8380 constant = tree_low_cst (primop0, 0); 8381 } 8382 else 8383 { 8384 primop = primop0; 8385 unsignedp = unsignedp0; 8386 constant = tree_low_cst (primop1, 0); 8387 } 8388 8389 bits = TYPE_PRECISION (TREE_TYPE (primop)); 8390 if (bits < TYPE_PRECISION (result_type) 8391 && bits < HOST_BITS_PER_WIDE_INT && unsignedp) 8392 { 8393 mask = (~(HOST_WIDE_INT) 0) << bits; 8394 if ((mask & constant) != mask) 8395 warning (0, "comparison of promoted ~unsigned with constant"); 8396 } 8397 } 8398 else if (unsignedp0 && unsignedp1 8399 && (TYPE_PRECISION (TREE_TYPE (primop0)) 8400 < TYPE_PRECISION (result_type)) 8401 && (TYPE_PRECISION (TREE_TYPE (primop1)) 8402 < TYPE_PRECISION (result_type))) 8403 warning (0, "comparison of promoted ~unsigned with unsigned"); 8404 } 8405 } 8406 } 8407 } 8408 8409 /* At this point, RESULT_TYPE must be nonzero to avoid an error message. 8410 If CONVERTED is zero, both args will be converted to type RESULT_TYPE. 8411 Then the expression will be built. 8412 It will be given type FINAL_TYPE if that is nonzero; 8413 otherwise, it will be given type RESULT_TYPE. */ 8414 8415 if (!result_type) 8416 { 8417 binary_op_error (code); 8418 return error_mark_node; 8419 } 8420 8421 if (!converted) 8422 { 8423 if (TREE_TYPE (op0) != result_type) 8424 op0 = convert_and_check (result_type, op0); 8425 if (TREE_TYPE (op1) != result_type) 8426 op1 = convert_and_check (result_type, op1); 8427 8428 /* This can happen if one operand has a vector type, and the other 8429 has a different type. */ 8430 if (TREE_CODE (op0) == ERROR_MARK || TREE_CODE (op1) == ERROR_MARK) 8431 return error_mark_node; 8432 } 8433 8434 if (build_type == NULL_TREE) 8435 build_type = result_type; 8436 8437 { 8438 /* Treat expressions in initializers specially as they can't trap. */ 8439 tree result = require_constant_value ? fold_build2_initializer (resultcode, 8440 build_type, 8441 op0, op1) 8442 : fold_build2 (resultcode, build_type, 8443 op0, op1); 8444 8445 if (final_type != 0) 8446 result = convert (final_type, result); 8447 return result; 8448 } 8449} 8450 8451 8452/* Convert EXPR to be a truth-value, validating its type for this 8453 purpose. */ 8454 8455tree 8456c_objc_common_truthvalue_conversion (tree expr) 8457{ 8458 switch (TREE_CODE (TREE_TYPE (expr))) 8459 { 8460 case ARRAY_TYPE: 8461 error ("used array that cannot be converted to pointer where scalar is required"); 8462 return error_mark_node; 8463 8464 case RECORD_TYPE: 8465 error ("used struct type value where scalar is required"); 8466 return error_mark_node; 8467 8468 case UNION_TYPE: 8469 error ("used union type value where scalar is required"); 8470 return error_mark_node; 8471 8472 case FUNCTION_TYPE: 8473 gcc_unreachable (); 8474 8475 default: 8476 break; 8477 } 8478 8479 /* ??? Should we also give an error for void and vectors rather than 8480 leaving those to give errors later? */ 8481 return c_common_truthvalue_conversion (expr); 8482} 8483 8484 8485/* Convert EXPR to a contained DECL, updating *TC, *TI and *SE as 8486 required. */ 8487 8488tree 8489c_expr_to_decl (tree expr, bool *tc ATTRIBUTE_UNUSED, 8490 bool *ti ATTRIBUTE_UNUSED, bool *se) 8491{ 8492 if (TREE_CODE (expr) == COMPOUND_LITERAL_EXPR) 8493 { 8494 tree decl = COMPOUND_LITERAL_EXPR_DECL (expr); 8495 /* Executing a compound literal inside a function reinitializes 8496 it. */ 8497 if (!TREE_STATIC (decl)) 8498 *se = true; 8499 return decl; 8500 } 8501 else 8502 return expr; 8503} 8504 8505/* Like c_begin_compound_stmt, except force the retention of the BLOCK. */ 8506 8507tree 8508c_begin_omp_parallel (void) 8509{ 8510 tree block; 8511 8512 keep_next_level (); 8513 block = c_begin_compound_stmt (true); 8514 8515 return block; 8516} 8517 8518tree 8519c_finish_omp_parallel (tree clauses, tree block) 8520{ 8521 tree stmt; 8522 8523 block = c_end_compound_stmt (block, true); 8524 8525 stmt = make_node (OMP_PARALLEL); 8526 TREE_TYPE (stmt) = void_type_node; 8527 OMP_PARALLEL_CLAUSES (stmt) = clauses; 8528 OMP_PARALLEL_BODY (stmt) = block; 8529 8530 return add_stmt (stmt); 8531} 8532 8533/* For all elements of CLAUSES, validate them vs OpenMP constraints. 8534 Remove any elements from the list that are invalid. */ 8535 8536tree 8537c_finish_omp_clauses (tree clauses) 8538{ 8539 bitmap_head generic_head, firstprivate_head, lastprivate_head; 8540 tree c, t, *pc = &clauses; 8541 const char *name; 8542 8543 bitmap_obstack_initialize (NULL); 8544 bitmap_initialize (&generic_head, &bitmap_default_obstack); 8545 bitmap_initialize (&firstprivate_head, &bitmap_default_obstack); 8546 bitmap_initialize (&lastprivate_head, &bitmap_default_obstack); 8547 8548 for (pc = &clauses, c = clauses; c ; c = *pc) 8549 { 8550 bool remove = false; 8551 bool need_complete = false; 8552 bool need_implicitly_determined = false; 8553 8554 switch (OMP_CLAUSE_CODE (c)) 8555 { 8556 case OMP_CLAUSE_SHARED: 8557 name = "shared"; 8558 need_implicitly_determined = true; 8559 goto check_dup_generic; 8560 8561 case OMP_CLAUSE_PRIVATE: 8562 name = "private"; 8563 need_complete = true; 8564 need_implicitly_determined = true; 8565 goto check_dup_generic; 8566 8567 case OMP_CLAUSE_REDUCTION: 8568 name = "reduction"; 8569 need_implicitly_determined = true; 8570 t = OMP_CLAUSE_DECL (c); 8571 if (AGGREGATE_TYPE_P (TREE_TYPE (t)) 8572 || POINTER_TYPE_P (TREE_TYPE (t))) 8573 { 8574 error ("%qE has invalid type for %<reduction%>", t); 8575 remove = true; 8576 } 8577 else if (FLOAT_TYPE_P (TREE_TYPE (t))) 8578 { 8579 enum tree_code r_code = OMP_CLAUSE_REDUCTION_CODE (c); 8580 const char *r_name = NULL; 8581 8582 switch (r_code) 8583 { 8584 case PLUS_EXPR: 8585 case MULT_EXPR: 8586 case MINUS_EXPR: 8587 break; 8588 case BIT_AND_EXPR: 8589 r_name = "&"; 8590 break; 8591 case BIT_XOR_EXPR: 8592 r_name = "^"; 8593 break; 8594 case BIT_IOR_EXPR: 8595 r_name = "|"; 8596 break; 8597 case TRUTH_ANDIF_EXPR: 8598 r_name = "&&"; 8599 break; 8600 case TRUTH_ORIF_EXPR: 8601 r_name = "||"; 8602 break; 8603 default: 8604 gcc_unreachable (); 8605 } 8606 if (r_name) 8607 { 8608 error ("%qE has invalid type for %<reduction(%s)%>", 8609 t, r_name); 8610 remove = true; 8611 } 8612 } 8613 goto check_dup_generic; 8614 8615 case OMP_CLAUSE_COPYPRIVATE: 8616 name = "copyprivate"; 8617 goto check_dup_generic; 8618 8619 case OMP_CLAUSE_COPYIN: 8620 name = "copyin"; 8621 t = OMP_CLAUSE_DECL (c); 8622 if (TREE_CODE (t) != VAR_DECL || !DECL_THREAD_LOCAL_P (t)) 8623 { 8624 error ("%qE must be %<threadprivate%> for %<copyin%>", t); 8625 remove = true; 8626 } 8627 goto check_dup_generic; 8628 8629 check_dup_generic: 8630 t = OMP_CLAUSE_DECL (c); 8631 if (TREE_CODE (t) != VAR_DECL && TREE_CODE (t) != PARM_DECL) 8632 { 8633 error ("%qE is not a variable in clause %qs", t, name); 8634 remove = true; 8635 } 8636 else if (bitmap_bit_p (&generic_head, DECL_UID (t)) 8637 || bitmap_bit_p (&firstprivate_head, DECL_UID (t)) 8638 || bitmap_bit_p (&lastprivate_head, DECL_UID (t))) 8639 { 8640 error ("%qE appears more than once in data clauses", t); 8641 remove = true; 8642 } 8643 else 8644 bitmap_set_bit (&generic_head, DECL_UID (t)); 8645 break; 8646 8647 case OMP_CLAUSE_FIRSTPRIVATE: 8648 name = "firstprivate"; 8649 t = OMP_CLAUSE_DECL (c); 8650 need_complete = true; 8651 need_implicitly_determined = true; 8652 if (TREE_CODE (t) != VAR_DECL && TREE_CODE (t) != PARM_DECL) 8653 { 8654 error ("%qE is not a variable in clause %<firstprivate%>", t); 8655 remove = true; 8656 } 8657 else if (bitmap_bit_p (&generic_head, DECL_UID (t)) 8658 || bitmap_bit_p (&firstprivate_head, DECL_UID (t))) 8659 { 8660 error ("%qE appears more than once in data clauses", t); 8661 remove = true; 8662 } 8663 else 8664 bitmap_set_bit (&firstprivate_head, DECL_UID (t)); 8665 break; 8666 8667 case OMP_CLAUSE_LASTPRIVATE: 8668 name = "lastprivate"; 8669 t = OMP_CLAUSE_DECL (c); 8670 need_complete = true; 8671 need_implicitly_determined = true; 8672 if (TREE_CODE (t) != VAR_DECL && TREE_CODE (t) != PARM_DECL) 8673 { 8674 error ("%qE is not a variable in clause %<lastprivate%>", t); 8675 remove = true; 8676 } 8677 else if (bitmap_bit_p (&generic_head, DECL_UID (t)) 8678 || bitmap_bit_p (&lastprivate_head, DECL_UID (t))) 8679 { 8680 error ("%qE appears more than once in data clauses", t); 8681 remove = true; 8682 } 8683 else 8684 bitmap_set_bit (&lastprivate_head, DECL_UID (t)); 8685 break; 8686 8687 case OMP_CLAUSE_IF: 8688 case OMP_CLAUSE_NUM_THREADS: 8689 case OMP_CLAUSE_SCHEDULE: 8690 case OMP_CLAUSE_NOWAIT: 8691 case OMP_CLAUSE_ORDERED: 8692 case OMP_CLAUSE_DEFAULT: 8693 pc = &OMP_CLAUSE_CHAIN (c); 8694 continue; 8695 8696 default: 8697 gcc_unreachable (); 8698 } 8699 8700 if (!remove) 8701 { 8702 t = OMP_CLAUSE_DECL (c); 8703 8704 if (need_complete) 8705 { 8706 t = require_complete_type (t); 8707 if (t == error_mark_node) 8708 remove = true; 8709 } 8710 8711 if (need_implicitly_determined) 8712 { 8713 const char *share_name = NULL; 8714 8715 if (TREE_CODE (t) == VAR_DECL && DECL_THREAD_LOCAL_P (t)) 8716 share_name = "threadprivate"; 8717 else switch (c_omp_predetermined_sharing (t)) 8718 { 8719 case OMP_CLAUSE_DEFAULT_UNSPECIFIED: 8720 break; 8721 case OMP_CLAUSE_DEFAULT_SHARED: 8722 share_name = "shared"; 8723 break; 8724 case OMP_CLAUSE_DEFAULT_PRIVATE: 8725 share_name = "private"; 8726 break; 8727 default: 8728 gcc_unreachable (); 8729 } 8730 if (share_name) 8731 { 8732 error ("%qE is predetermined %qs for %qs", 8733 t, share_name, name); 8734 remove = true; 8735 } 8736 } 8737 } 8738 8739 if (remove) 8740 *pc = OMP_CLAUSE_CHAIN (c); 8741 else 8742 pc = &OMP_CLAUSE_CHAIN (c); 8743 } 8744 8745 bitmap_obstack_release (NULL); 8746 return clauses; 8747} 8748