1; Options for the Fortran front end. 2; Copyright (C) 2003-2022 Free Software Foundation, Inc. 3; 4; This file is part of GCC. 5; 6; GCC is free software; you can redistribute it and/or modify it under 7; the terms of the GNU General Public License as published by the Free 8; Software Foundation; either version 3, or (at your option) any later 9; version. 10; 11; GCC is distributed in the hope that it will be useful, but WITHOUT ANY 12; WARRANTY; without even the implied warranty of MERCHANTABILITY or 13; FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14; for more details. 15; 16; You should have received a copy of the GNU General Public License 17; along with GCC; see the file COPYING3. If not see 18; <http://www.gnu.org/licenses/>. 19 20; See the GCC internals manual for a description of this file's format. 21 22; Please try to keep this file in ASCII collating order. 23 24Language 25Fortran 26 27-all-warnings 28Fortran Alias(Wall) 29 30-assert 31Fortran Separate Alias(A) 32 33-assert= 34Fortran Joined Alias(A) 35 36-comments 37Fortran Alias(C) 38 39-comments-in-macros 40Fortran Alias(CC) 41 42-define-macro 43Fortran Separate Alias(D) 44 45-define-macro= 46Fortran Joined Alias(D) 47 48-dependencies 49Fortran Alias(M) 50 51-dump 52Fortran Separate Alias(d) 53 54-dump= 55Fortran Joined Alias(d) 56 57-include-barrier 58Fortran Alias(I, -) 59 60-include-directory 61Fortran Separate Alias(I) 62 63-include-directory= 64Fortran Joined Alias(I) 65 66-include-directory-after 67Fortran Separate Alias(idirafter) 68 69-include-directory-after= 70Fortran Joined Alias(idirafter) 71 72-include-prefix 73Fortran Separate Alias(iprefix) 74 75-include-prefix= 76Fortran JoinedOrMissing Alias(iprefix) 77 78-no-line-commands 79Fortran Alias(P) 80 81-no-standard-includes 82Fortran Alias(nostdinc) 83 84-output 85Fortran Separate Alias(o) 86 87-output= 88Fortran Joined Alias(o) 89 90-preprocess 91Fortran Undocumented Alias(E) 92 93-print-missing-file-dependencies 94Fortran Alias(MG) 95 96-trace-includes 97Fortran Alias(H) 98 99-undefine-macro 100Fortran Separate Alias(U) 101 102-undefine-macro= 103Fortran Joined Alias(U) 104 105-user-dependencies 106Fortran Alias(MM) 107 108-verbose 109Fortran Alias(v) 110 111-write-dependencies 112Fortran NoDriverArg Separate Alias(MD) 113 114-write-user-dependencies 115Fortran NoDriverArg Separate Alias(MMD) 116 117A 118Fortran Joined Separate 119; Documented in C 120 121C 122Fortran 123; Documented in C 124 125CC 126Fortran 127; Documented in C 128 129D 130Fortran Joined Separate 131; Documented in C 132 133E 134Fortran Undocumented 135 136H 137Fortran 138; Documented in C 139 140I 141Fortran Joined Separate 142; Documented in C 143 144J 145Fortran Joined Separate 146-J<directory> Put MODULE files in 'directory'. 147 148M 149Fortran 150; Documented in C 151 152MD 153Fortran Separate NoDriverArg 154; Documented in C 155 156MF 157Fortran Joined Separate 158; Documented in C 159 160MG 161Fortran 162; Documented in C 163 164MM 165Fortran 166; Documented in C 167 168MMD 169Fortran Separate NoDriverArg 170; Documented in C 171 172MP 173Fortran 174; Documented in C 175 176MT 177Fortran Joined Separate 178; Documented in C 179 180MQ 181Fortran Joined Separate 182; Documented in C 183 184P 185Fortran 186; Documented in C 187 188U 189Fortran Joined Separate 190; Documented in C 191 192Wall 193Fortran 194; Documented in C 195 196Waliasing 197Fortran Warning Var(warn_aliasing) LangEnabledBy(Fortran,Wall) 198Warn about possible aliasing of dummy arguments. 199 200Walign-commons 201Fortran Warning Var(warn_align_commons) Init(1) 202Warn about alignment of COMMON blocks. 203 204Wampersand 205Fortran Warning Var(warn_ampersand) LangEnabledBy(Fortran,Wall || Wpedantic) 206Warn about missing ampersand in continued character constants. 207 208Warray-temporaries 209Fortran Warning Var(warn_array_temporaries) 210Warn about creation of array temporaries. 211 212Wargument-mismatch 213Fortran WarnRemoved 214Does nothing. Preserved for backward compatibility. 215 216Wc-binding-type 217Fortran Var(warn_c_binding_type) Warning LangEnabledBy(Fortran,Wall) 218Warn if the type of a variable might be not interoperable with C. 219 220Wdate-time 221Fortran 222; Documented in C 223 224Wcharacter-truncation 225Fortran Var(warn_character_truncation) Warning LangEnabledBy(Fortran,Wall) 226Warn about truncated character expressions. 227 228Wcompare-reals 229Fortran Warning Var(warn_compare_reals) LangEnabledBy(Fortran,Wextra) 230Warn about equality comparisons involving REAL or COMPLEX expressions. 231 232Wconversion 233Fortran Var(warn_conversion) Warning LangEnabledBy(Fortran,Wall) 234; Documented in C 235 236Wconversion-extra 237Fortran Var(warn_conversion_extra) Warning 238Warn about most implicit conversions. 239 240Wdo-subscript 241Fortran Var(warn_do_subscript) Warning LangEnabledBy(Fortran,Wextra) 242Warn about possibly incorrect subscripts in do loops. 243 244Wextra 245Fortran Warning 246; Documented in common 247 248Wfrontend-loop-interchange 249Fortran Var(flag_warn_frontend_loop_interchange) 250Warn if loops have been interchanged. 251 252Wfunction-elimination 253Fortran Warning Var(warn_function_elimination) LangEnabledBy(Fortran,Wextra) 254Warn about function call elimination. 255 256Wimplicit-interface 257Fortran Warning Var(warn_implicit_interface) 258Warn about calls with implicit interface. 259 260Wimplicit-procedure 261Fortran Warning Var(warn_implicit_procedure) 262Warn about called procedures not explicitly declared. 263 264Winteger-division 265Fortran Warning Var(warn_integer_division) LangEnabledBy(Fortran,Wall) 266Warn about constant integer divisions with truncated results. 267 268Wline-truncation 269Fortran Warning Var(warn_line_truncation) LangEnabledBy(Fortran,Wall) Init(-1) 270Warn about truncated source lines. 271 272Wintrinsics-std 273Fortran Var(warn_intrinsics_std) Warning LangEnabledBy(Fortran,Wall) 274Warn on intrinsics not part of the selected standard. 275 276Wmaybe-uninitialized 277Fortran LangEnabledBy(Fortran,Wall) 278; Documented in common.opt 279 280Wmissing-include-dirs 281Fortran 282; Documented in C/C++ 283 284Wuse-without-only 285Fortran Var(warn_use_without_only) Warning 286Warn about USE statements that have no ONLY qualifier. 287 288Wopenacc-parallelism 289Fortran 290; Documented in C 291 292Wopenmp-simd 293Fortran 294; Documented in C 295 296Woverwrite-recursive 297Fortran Warning Var(warn_overwrite_recursive) Init(1) 298Warn that -fno-automatic may break recursion. 299 300Wpedantic 301Fortran 302; Documented in common.opt 303 304Wreal-q-constant 305Fortran Warning Var(warn_real_q_constant) LangEnabledBy(Fortran,Wall) 306Warn about real-literal-constants with 'q' exponent-letter. 307 308Wrealloc-lhs 309Fortran Warning Var(warn_realloc_lhs) LangEnabledBy(Fortran,Wrealloc-lhs-all) 310Warn when a left-hand-side array variable is reallocated. 311 312Wrealloc-lhs-all 313Fortran Warning Var(warn_realloc_lhs_all) 314Warn when a left-hand-side variable is reallocated. 315 316Wtarget-lifetime 317Fortran Warning Var(warn_target_lifetime) LangEnabledBy(Fortran,Wall) 318Warn if the pointer in a pointer assignment might outlive its target. 319 320Wreturn-type 321Fortran Warning LangEnabledBy(Fortran,Wall) 322; Documented in C 323 324Wsurprising 325Fortran Warning Var(warn_surprising) LangEnabledBy(Fortran,Wall) 326Warn about \"suspicious\" constructs. 327 328Wtabs 329Fortran Warning Var(warn_tabs) LangEnabledBy(Fortran,Wall || Wpedantic) 330Permit nonconforming uses of the tab character. 331 332Wundefined-do-loop 333Fortran Warning Var(warn_undefined_do_loop) LangEnabledBy(Fortran,Wall) 334Warn about an invalid DO loop. 335 336Wunderflow 337Fortran Warning Var(warn_underflow) Init(1) 338Warn about underflow of numerical constant expressions. 339 340Wuninitialized 341Fortran LangEnabledBy(Fortran,Wall) 342; Documented in common.opt 343 344Wintrinsic-shadow 345Fortran Warning Var(warn_intrinsic_shadow) LangEnabledBy(Fortran,Wall) 346Warn if a user-procedure has the same name as an intrinsic. 347 348Wunused 349LangEnabledBy(Fortran,Wall) 350; Documented in common.opt 351 352Wunused-dummy-argument 353Fortran Warning Var(warn_unused_dummy_argument) LangEnabledBy(Fortran,Wall) 354Warn about unused dummy arguments. 355 356Wzerotrip 357Fortran Warning Var(warn_zerotrip) LangEnabledBy(Fortran,Wall) 358Warn about zero-trip DO loops. 359 360cpp 361Fortran Negative(nocpp) 362Enable preprocessing. 363 364cpp= 365Fortran Joined Negative(nocpp) Undocumented NoDWARFRecord 366; Internal option generated by specs from -cpp. 367 368nocpp 369Fortran Negative(cpp) 370Disable preprocessing. 371 372d 373Fortran Joined 374; Documented in common.opt 375 376fallow-argument-mismatch 377Fortran Var(flag_allow_argument_mismatch) LangEnabledBy(Fortran,std=legacy) 378Accept argument mismatches in procedure calls. 379 380faggressive-function-elimination 381Fortran Var(flag_aggressive_function_elimination) 382Eliminate multiple function invocations also for impure functions. 383 384falign-commons 385Fortran Var(flag_align_commons) Init(1) 386Enable alignment of COMMON blocks. 387 388fall-intrinsics 389Fortran RejectNegative Var(flag_all_intrinsics) 390All intrinsics procedures are available regardless of selected standard. 391 392fallow-invalid-boz 393Fortran RejectNegative Var(flag_allow_invalid_boz) 394Allow a BOZ literal constant to appear in an invalid context and with X instead of Z. 395 396fallow-leading-underscore 397Fortran Undocumented Var(flag_allow_leading_underscore) 398; For internal use only: allow the first character of symbol names to be an underscore 399 400fautomatic 401Fortran Var(flag_automatic) Init(1) 402Do not treat local variables and COMMON blocks as if they were named in SAVE statements. 403 404fbackslash 405Fortran Var(flag_backslash) 406Specify that backslash in string introduces an escape character. 407 408fbacktrace 409Fortran Var(flag_backtrace) Init(1) 410Produce a backtrace when a runtime error is encountered. 411 412fblas-matmul-limit= 413Fortran RejectNegative Joined UInteger Var(flag_blas_matmul_limit) Init(30) 414-fblas-matmul-limit=<n> Size of the smallest matrix for which matmul will use BLAS. 415 416fbuilding-libgfortran 417Fortran Undocumented Var(flag_building_libgfortran) 418 419fcheck-array-temporaries 420Fortran 421Produce a warning at runtime if a array temporary has been created for a procedure argument. 422 423fconvert= 424Fortran RejectNegative Joined Enum(gfc_convert) EnumSet Var(flag_convert) Init(GFC_FLAG_CONVERT_NATIVE) 425-fconvert=<big-endian|little-endian|native|swap|r16_ieee|r16_ibm> The endianness used for unformatted files. 426 427Enum 428Name(gfc_convert) Type(enum gfc_convert) UnknownError(Unrecognized option to endianness value: %qs) 429 430EnumValue 431Enum(gfc_convert) String(big-endian) Value(GFC_FLAG_CONVERT_BIG) Set(1) 432 433EnumValue 434Enum(gfc_convert) String(little-endian) Value(GFC_FLAG_CONVERT_LITTLE) Set(1) 435 436EnumValue 437Enum(gfc_convert) String(native) Value(GFC_FLAG_CONVERT_NATIVE) Set(1) 438 439EnumValue 440Enum(gfc_convert) String(swap) Value(GFC_FLAG_CONVERT_SWAP) Set(1) 441 442EnumValue 443Enum(gfc_convert) String(r16_ieee) Value(GFC_FLAG_CONVERT_R16_IEEE) Set(2) 444 445EnumValue 446Enum(gfc_convert) String(r16_ibm) Value(GFC_FLAG_CONVERT_R16_IBM) Set(2) 447 448fcray-pointer 449Fortran Var(flag_cray_pointer) 450Use the Cray Pointer extension. 451 452fc-prototypes 453Fortran Var(flag_c_prototypes) 454Generate C prototypes from BIND(C) declarations. 455 456fc-prototypes-external 457Fortran Var(flag_c_prototypes_external) 458Generate C prototypes from non-BIND(C) external procedure definitions. 459 460fd-lines-as-code 461Fortran RejectNegative 462Ignore 'D' in column one in fixed form. 463 464fd-lines-as-comments 465Fortran RejectNegative 466Treat lines with 'D' in column one as comments. 467 468fdebug-aux-vars 469Fortran Var(flag_debug_aux_vars) 470Issue debug information for compiler-generated auxiliary variables. 471 472fdec 473Fortran Var(flag_dec) 474Enable all DEC language extensions. 475 476fdec-blank-format-item 477Fortran Var(flag_dec_blank_format_item) 478Enable the use of blank format items in format strings. 479 480fdec-char-conversions 481Fortran Var(flag_dec_char_conversions) 482Enable the use of character literals in assignments and data statements 483for non-character variables. 484 485fdec-include 486Fortran Var(flag_dec_include) 487Enable legacy parsing of INCLUDE as statement. 488 489fdec-format-defaults 490Fortran Var(flag_dec_format_defaults) 491Enable default widths for i, f and g format specifiers. 492 493fdec-intrinsic-ints 494Fortran Var(flag_dec_intrinsic_ints) 495Enable kind-specific variants of integer intrinsic functions. 496 497fdec-math 498Fortran Var(flag_dec_math) 499Enable legacy math intrinsics for compatibility. 500 501fdec-structure 502Fortran Var(flag_dec_structure) 503Enable support for DEC STRUCTURE/RECORD. 504 505fdec-static 506Fortran Var(flag_dec_static) 507Enable DEC-style STATIC and AUTOMATIC attributes. 508 509fdefault-double-8 510Fortran Var(flag_default_double) 511Set the default double precision kind to an 8 byte wide type. 512 513fdefault-integer-8 514Fortran Var(flag_default_integer) 515Set the default integer kind to an 8 byte wide type. 516 517fdefault-real-8 518Fortran Var(flag_default_real_8) 519Set the default real kind to an 8 byte wide type. 520 521fdefault-real-10 522Fortran Var(flag_default_real_10) 523Set the default real kind to an 10 byte wide type. 524 525fdefault-real-16 526Fortran Var(flag_default_real_16) 527Set the default real kind to an 16 byte wide type. 528 529fdollar-ok 530Fortran Var(flag_dollar_ok) 531Allow dollar signs in entity names. 532 533fdump-core 534Fortran Ignore 535Does nothing. Preserved for backward compatibility. 536 537fdump-fortran-original 538Fortran Var(flag_dump_fortran_original) 539Display the code tree after parsing. 540 541fdump-fortran-optimized 542Fortran Var(flag_dump_fortran_optimized) 543Display the code tree after front end optimization. 544 545fdump-fortran-global 546Fortran Var(flag_dump_fortran_global) 547Display the global symbol table after parsing. 548 549fdump-parse-tree 550Fortran Alias(fdump-fortran-original) 551Display the code tree after parsing; deprecated option. 552 553fexternal-blas 554Fortran Var(flag_external_blas) 555Specify that an external BLAS library should be used for matmul calls on large-size arrays. 556 557ff2c 558Fortran Var(flag_f2c) 559Use f2c calling convention. 560 561ffixed-form 562Fortran RejectNegative 563Assume that the source file is fixed form. 564 565ftest-forall-temp 566Fortran Var(flag_test_forall_temp) Init(0) 567Force creation of temporary to test infrequently-executed forall code. 568 569finteger-4-integer-8 570Fortran RejectNegative Var(flag_integer4_kind,8) 571Interpret any INTEGER(4) as an INTEGER(8). 572 573fintrinsic-modules-path 574Fortran RejectNegative Separate 575Specify where to find the compiled intrinsic modules. 576 577fintrinsic-modules-path= 578Fortran RejectNegative Joined 579Specify where to find the compiled intrinsic modules. 580 581ffixed-line-length-none 582Fortran RejectNegative Var(flag_fixed_line_length,0) 583Allow arbitrary character line width in fixed mode. 584 585ffixed-line-length- 586Fortran RejectNegative Joined UInteger Var(flag_fixed_line_length) Init(72) 587-ffixed-line-length-<n> Use n as character line width in fixed mode. 588 589fpad-source 590Fortran Var(flag_pad_source) Init(1) 591Pad shorter fixed form lines to line width with spaces. 592 593ffpe-trap= 594Fortran RejectNegative JoinedOrMissing 595-ffpe-trap=[...] Stop on following floating point exceptions. 596 597ffpe-summary= 598Fortran RejectNegative JoinedOrMissing 599-ffpe-summary=[...] Print summary of floating point exceptions. 600 601ffree-form 602Fortran RejectNegative 603Assume that the source file is free form. 604 605ffree-line-length-none 606Fortran RejectNegative Var(flag_free_line_length,0) 607Allow arbitrary character line width in free mode. 608 609ffree-line-length- 610Fortran RejectNegative Joined UInteger Var(flag_free_line_length) Init(132) 611-ffree-line-length-<n> Use n as character line width in free mode. 612 613ffrontend-loop-interchange 614Fortran Var(flag_frontend_loop_interchange) Init(-1) 615Try to interchange loops if profitable. 616 617ffrontend-optimize 618Fortran Var(flag_frontend_optimize) Init(-1) 619Enable front end optimization. 620 621fimplicit-none 622Fortran Var(flag_implicit_none) 623Specify that no implicit typing is allowed, unless overridden by explicit IMPLICIT statements. 624 625finit-character= 626Fortran RejectNegative Joined UInteger 627-finit-character=<n> Initialize local character variables to ASCII value n. 628 629finit-derived 630Fortran Var(flag_init_derived) 631Initialize components of derived type variables according to other init flags. 632 633finit-integer= 634Fortran RejectNegative Joined 635-finit-integer=<n> Initialize local integer variables to n. 636 637finit-local-zero 638Fortran 639Initialize local variables to zero (from g77). 640 641finit-logical= 642Fortran RejectNegative Joined 643-finit-logical=<true|false> Initialize local logical variables. 644 645finit-real= 646Fortran RejectNegative ToLower Joined Enum(gfc_init_local_real) Var(flag_init_real) Init(GFC_INIT_REAL_OFF) 647-finit-real=<zero|snan|nan|inf|-inf> Initialize local real variables. 648 649Enum 650Name(gfc_init_local_real) Type(enum gfc_init_local_real) UnknownError(Unrecognized option to floating-point init value: %qs) 651 652EnumValue 653Enum(gfc_init_local_real) String(zero) Value(GFC_INIT_REAL_ZERO) 654 655EnumValue 656Enum(gfc_init_local_real) String(snan) Value(GFC_INIT_REAL_SNAN) 657 658EnumValue 659Enum(gfc_init_local_real) String(nan) Value(GFC_INIT_REAL_NAN) 660 661EnumValue 662Enum(gfc_init_local_real) String(inf) Value(GFC_INIT_REAL_INF) 663 664EnumValue 665Enum(gfc_init_local_real) String(-inf) Value(GFC_INIT_REAL_NEG_INF) 666 667finline-arg-packing 668Fortran Var(flag_inline_arg_packing) Init(-1) 669-finline-arg-packing Perform argument packing inline. 670 671finline-matmul-limit= 672Fortran RejectNegative Joined UInteger Var(flag_inline_matmul_limit) Init(-1) 673-finline-matmul-limit=<n> Specify the size of the largest matrix for which matmul will be inlined. 674 675fmax-array-constructor= 676Fortran RejectNegative Joined UInteger Var(flag_max_array_constructor) Init(65535) 677-fmax-array-constructor=<n> Maximum number of objects in an array constructor. 678 679fmax-identifier-length= 680Fortran RejectNegative Joined UInteger 681-fmax-identifier-length=<n> Maximum identifier length. 682 683fmax-subrecord-length= 684Fortran RejectNegative Joined UInteger Var(flag_max_subrecord_length) 685-fmax-subrecord-length=<n> Maximum length for subrecords. 686 687fmax-stack-var-size= 688Fortran RejectNegative Joined UInteger Var(flag_max_stack_var_size) Init(-2) 689-fmax-stack-var-size=<n> Size in bytes of the largest array that will be put on the stack. 690 691fstack-arrays 692Fortran Var(flag_stack_arrays) Init(-1) 693Put all local arrays on stack. 694 695fmodule-private 696Fortran Var(flag_module_private) 697Set default accessibility of module entities to PRIVATE. 698 699fopenacc 700Fortran LTO 701; Documented in C 702 703fopenacc-dim= 704Fortran LTO Joined Var(flag_openacc_dims) 705; Documented in C 706 707fopenmp 708Fortran LTO 709; Documented in C 710 711fopenmp-simd 712Fortran 713; Documented in C 714 715fpack-derived 716Fortran Var(flag_pack_derived) 717Try to lay out derived types as compactly as possible. 718 719fpreprocessed 720Fortran 721; Documented in C 722 723fprotect-parens 724Fortran Var(flag_protect_parens) Init(-1) 725Protect parentheses in expressions. 726 727fpre-include= 728Fortran RejectNegative Joined Var(flag_pre_include) Undocumented 729Path to header file that should be pre-included before each compilation unit. 730 731frange-check 732Fortran Var(flag_range_check) Init(1) 733Enable range checking during compilation. 734 735freal-4-real-8 736Fortran RejectNegative Var(flag_real4_kind,8) 737Interpret any REAL(4) as a REAL(8). 738 739freal-4-real-10 740Fortran RejectNegative Var(flag_real4_kind,10) 741Interpret any REAL(4) as a REAL(10). 742 743freal-4-real-16 744Fortran RejectNegative Var(flag_real4_kind,16) 745Interpret any REAL(4) as a REAL(16). 746 747freal-8-real-4 748Fortran RejectNegative Var(flag_real8_kind,4) 749Interpret any REAL(8) as a REAL(4). 750 751freal-8-real-10 752Fortran RejectNegative Var(flag_real8_kind,10) 753Interpret any REAL(8) as a REAL(10). 754 755freal-8-real-16 756Fortran RejectNegative Var(flag_real8_kind,16) 757Interpret any REAL(8) as a REAL(16). 758 759frealloc-lhs 760Fortran Var(flag_realloc_lhs) Init(-1) 761Reallocate the LHS in assignments. 762 763frecord-marker=4 764Fortran RejectNegative Var(flag_record_marker,4) 765Use a 4-byte record marker for unformatted files. 766 767frecord-marker=8 768Fortran RejectNegative Var(flag_record_marker,8) 769Use an 8-byte record marker for unformatted files. 770 771frecursive 772Fortran Var(flag_recursive) 773Allocate local variables on the stack to allow indirect recursion. 774 775frepack-arrays 776Fortran Var(flag_repack_arrays) 777Copy array sections into a contiguous block on procedure entry. 778 779fcoarray= 780Fortran RejectNegative Joined Enum(gfc_fcoarray) Var(flag_coarray) Init(GFC_FCOARRAY_NONE) 781-fcoarray=<none|single|lib> Specify which coarray parallelization should be used. 782 783Enum 784Name(gfc_fcoarray) Type(enum gfc_fcoarray) UnknownError(Unrecognized option: %qs) 785 786EnumValue 787Enum(gfc_fcoarray) String(none) Value(GFC_FCOARRAY_NONE) 788 789EnumValue 790Enum(gfc_fcoarray) String(single) Value(GFC_FCOARRAY_SINGLE) 791 792EnumValue 793Enum(gfc_fcoarray) String(lib) Value(GFC_FCOARRAY_LIB) 794 795fcheck= 796Fortran RejectNegative JoinedOrMissing 797-fcheck=[...] Specify which runtime checks are to be performed. 798 799fsecond-underscore 800Fortran Var(flag_second_underscore) Init(-1) 801Append a second underscore if the name already contains an underscore. 802 803fshort-enums 804Fortran Var(flag_short_enums) 805; Documented in C 806 807fsign-zero 808Fortran Var(flag_sign_zero) Init(1) 809Apply negative sign to zero values. 810 811ftail-call-workaround 812Fortran Alias(ftail-call-workaround=,1,0) 813 814ftail-call-workaround= 815Fortran RejectNegative Joined UInteger IntegerRange(0, 2) Var(flag_tail_call_workaround) Init(1) 816Disallow tail call optimization when a calling routine may have omitted character lengths. 817 818funderscoring 819Fortran Var(flag_underscoring) Init(1) 820Append underscores to externally visible names. 821 822fwhole-file 823Fortran Ignore 824Does nothing. Preserved for backward compatibility. 825 826fworking-directory 827Fortran 828; Documented in C 829 830idirafter 831Fortran Joined Separate 832; Documented in C 833 834imultilib 835Fortran Joined Separate 836; Documented in C 837 838iprefix 839Fortran Joined Separate 840; Documented in C 841 842iquote 843Fortran Joined Separate 844; Documented in C 845 846isysroot 847Fortran Joined Separate 848; Documented in C 849 850isystem 851Fortran Joined Separate 852; Documented in C 853 854nostdinc 855Fortran 856; Documented in C 857 858o 859Fortran Joined Separate 860; Documented in common.opt 861 862static-libgfortran 863Fortran 864Statically link the GNU Fortran helper library (libgfortran). 865 866std=f2003 867Fortran 868Conform to the ISO Fortran 2003 standard. 869 870std=f2008 871Fortran 872Conform to the ISO Fortran 2008 standard. 873 874std=f2008ts 875Fortran 876Conform to the ISO Fortran 2008 standard including TS 29113. 877 878std=f2018 879Fortran 880Conform to the ISO Fortran 2018 standard. 881 882std=f95 883Fortran 884Conform to the ISO Fortran 95 standard. 885 886std=gnu 887Fortran 888Conform to nothing in particular. 889 890std=legacy 891Fortran 892Accept extensions to support legacy code. 893 894undef 895Fortran 896; Documented in C 897 898v 899Fortran 900; Documented in C 901 902; This comment is to ensure we retain the blank line above. 903