gcc/common.opt

   1 ; Options for the language- and target-independent parts of the compiler.
   2
   3 ; Copyright (C) 2003-2016 Free Software Foundation, Inc.
   4 ;
   5 ; This file is part of GCC.
   6 ;
   7 ; GCC is free software; you can redistribute it and/or modify it under
   8 ; the terms of the GNU General Public License as published by the Free
   9 ; Software Foundation; either version 3, or (at your option) any later
  10 ; version.
  11 ;
  12 ; GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  13 ; WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14 ; FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  15 ; for more details.
  16 ;
  17 ; You should have received a copy of the GNU General Public License
  18 ; along with GCC; see the file COPYING3.  If not see
  19 ; <http://www.gnu.org/licenses/>.
  20
  21 ; See the GCC internals manual (options.texi) for a description of this file's format.
  22
  23 ; Please try to keep this file in ASCII collating order.
  24
  25 Variable
  26 int target_flags
  27
  28 Variable
  29 int optimize
  30
  31 Variable
  32 int optimize_size
  33
  34 Variable
  35 int optimize_debug
  36
  37 ; Not used directly to control optimizations, only to save -Ofast
  38 ; setting for "optimize" attributes.
  39 Variable
  40 int optimize_fast
  41
  42 ; True if this is the lto front end.  This is used to disable gimple
  43 ; generation and lowering passes that are normally run on the output
  44 ; of a front end.  These passes must be bypassed for lto since they
  45 ; have already been done before the gimple was written.
  46 Variable
  47 bool in_lto_p = false
  48
  49 ; This variable is set to non-0 only by LTO front-end.  1 indicates that
  50 ; the output produced will be used for incrmeental linking (thus weak symbols
  51 ; can still be bound).
  52 Variable
  53 int flag_incremental_link = 0
  54
  55 ; 0 means straightforward implementation of complex divide acceptable.
  56 ; 1 means wide ranges of inputs must work for complex divide.
  57 ; 2 means C99-like requirements for complex multiply and divide.
  58 Variable
  59 int flag_complex_method = 1
  60
  61 ; Nonzero if subexpressions must be evaluated from left-to-right.
  62 Variable
  63 int flag_evaluation_order = 0
  64
  65 ; Language specific warning pass for unused results.
  66 Variable
  67 bool flag_warn_unused_result = false
  68
  69 Variable
  70 int *param_values
  71
  72 ; Nonzero if we should write GIMPLE bytecode for link-time optimization.
  73 Variable
  74 int flag_generate_lto
  75
  76 ; Nonzero if we should write GIMPLE bytecode for offload compilation.
  77 Variable
  78 int flag_generate_offload = 0
  79
  80 ; True to warn about any objects definitions whose size is larger
  81 ; than N bytes.  Also want about function definitions whose returned
  82 ; values are larger than N bytes, where N is 'larger_than_size'.
  83 Variable
  84 bool warn_larger_than
  85
  86 Variable
  87 HOST_WIDE_INT larger_than_size
  88
  89 ; True to warn about any function whose frame size is larger
  90 ; than N bytes.
  91 Variable
  92 bool warn_frame_larger_than
  93
  94 Variable
  95 HOST_WIDE_INT frame_larger_than_size
  96
  97 ; Nonzero means we should be saving declaration info into a .X file.
  98 Variable
  99 int flag_gen_aux_info = 0
 100
 101 ; Nonzero if we are compiling code for a shared library, zero for
 102 ; executable.
 103 Variable
 104 int flag_shlib
 105
 106 ; These two are really VEC(char_p,heap) *.
 107
 108 Variable
 109 void *flag_instrument_functions_exclude_functions
 110
 111 Variable
 112 void *flag_instrument_functions_exclude_files
 113
 114 ; Generic structs (e.g. templates not explicitly specialized)
 115 ; may not have a compilation unit associated with them, and so
 116 ; may need to be treated differently from ordinary structs.
 117 ;
 118 ; Structs only handled by reference (indirectly), will also usually
 119 ; not need as much debugging information.
 120
 121 Variable
 122 enum debug_struct_file debug_struct_ordinary[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
 123
 124 Variable
 125 enum debug_struct_file debug_struct_generic[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
 126
 127 ; True if we should exit after parsing options.
 128 Variable
 129 bool exit_after_options
 130
 131 ; Type(s) of debugging information we are producing (if any).  See
 132 ; flag-types.h for the definitions of the different possible types of
 133 ; debugging information.
 134 Variable
 135 enum debug_info_type write_symbols = NO_DEBUG
 136
 137 ; Level of debugging information we are producing.  See flag-types.h
 138 ; for the definitions of the different possible levels.
 139 Variable
 140 enum debug_info_levels debug_info_level = DINFO_LEVEL_NONE
 141
 142 ; Nonzero means use GNU-only extensions in the generated symbolic
 143 ; debugging information.  Currently, this only has an effect when
 144 ; write_symbols is set to DBX_DEBUG, XCOFF_DEBUG, or DWARF_DEBUG.
 145 Variable
 146 bool use_gnu_debug_info_extensions
 147
 148 ; Original value of maximum field alignment in bytes, specified via
 149 ; -fpack-struct=<value>.
 150 Variable
 151 unsigned int initial_max_fld_align = TARGET_DEFAULT_PACK_STRUCT
 152
 153 ; Type of stack check.
 154 Variable
 155 enum stack_check_type flag_stack_check = NO_STACK_CHECK
 156
 157 ; True if stack usage information needs to be computed.
 158 Variable
 159 bool flag_stack_usage_info = false
 160
 161 ; -dA causes debug commentary information to be produced in
 162 ; the generated assembly code (to make it more readable).  This option
 163 ; is generally only of use to those who actually need to read the
 164 ; generated assembly code (perhaps while debugging the compiler itself).
 165 ; Currently, this switch is only used by dwarf2out.c; however, it is intended
 166 ; to be a catchall for printing debug information in the assembler file.
 167 Variable
 168 int flag_debug_asm
 169
 170
 171 ; Balance between GNAT encodings and standard DWARF to emit.
 172 Variable
 173 enum dwarf_gnat_encodings gnat_encodings = DWARF_GNAT_ENCODINGS_DEFAULT
 174
 175 ; -dP causes the rtl to be emitted as a comment in assembly.
 176 Variable
 177 int flag_dump_rtl_in_asm
 178
 179 ; Whether -da was passed (used only in handle_common_deferred_options).
 180 Variable
 181 bool flag_dump_all_passed
 182
 183 ; Other flags saying which kinds of debugging dump have been requested.
 184
 185 Variable
 186 int rtl_dump_and_exit
 187
 188 Variable
 189 int flag_print_asm_name
 190
 191 ; Name of top-level original source file (what was input to cpp).
 192 ; This comes from the #-command at the beginning of the actual input.
 193 ; If there isn't any there, then this is the cc1 input file name.
 194 Variable
 195 const char *main_input_filename
 196
 197 ; Pointer to base name in main_input_filename, with directories and a
 198 ; single final extension removed, and the length of this base
 199 ; name.
 200
 201 Variable
 202 const char *main_input_basename
 203
 204 Variable
 205 int main_input_baselength
 206
 207 ; Which options have been printed by --help.
 208 Variable
 209 char *help_printed
 210
 211 ; Which enums have been printed by --help.  0 = not printed, no
 212 ; relevant options seen, 1 = relevant option seen, not yet printed, 2
 213 ; = printed.
 214 Variable
 215 char *help_enum_printed
 216
 217 ; The number of columns for --help output.
 218 Variable
 219 unsigned int help_columns
 220
 221 ; Whether this options structure has been through finish_options
 222 Variable
 223 bool flag_opts_finished
 224
 225 ; What the sanitizer should instrument
 226 Variable
 227 unsigned int flag_sanitize
 228
 229 ; What sanitizers should recover from errors
 230 Variable
 231 unsigned int flag_sanitize_recover = SANITIZE_UNDEFINED | SANITIZE_NONDEFAULT | SANITIZE_KERNEL_ADDRESS
 232
 233 fsanitize-coverage=trace-pc
 234 Common Report Var(flag_sanitize_coverage)
 235 Enable coverage-guided fuzzing code instrumentation.
 236 Inserts call to __sanitizer_cov_trace_pc into every basic block.
 237
 238 ; Flag whether a prefix has been added to dump_base_name
 239 Variable
 240 bool dump_base_name_prefixed = false
 241
 242 ; Flag whether HSA generation has been explicitely disabled
 243 Variable
 244 bool flag_disable_hsa = false
 245
 246 ###
 247 Driver
 248
 249 -assemble
 250 Driver Alias(S)
 251
 252 -compile
 253 Driver Alias(c)
 254
 255 -coverage
 256 Driver Alias(coverage)
 257
 258 -debug
 259 Common Alias(g)
 260
 261 -dump
 262 Common Separate Alias(d)
 263
 264 -dump=
 265 Common Joined Alias(d)
 266
 267 -dumpbase
 268 Common Separate Alias(dumpbase)
 269
 270 -dumpdir
 271 Common Separate Alias(dumpdir)
 272
 273 -entry
 274 Driver Separate Alias(e)
 275
 276 -entry=
 277 Driver Joined Alias(e)
 278
 279 -extra-warnings
 280 Common Warning Alias(Wextra)
 281
 282 -for-assembler
 283 Driver Separate Alias(Xassembler)
 284
 285 -for-assembler=
 286 Driver JoinedOrMissing Alias(Xassembler)
 287
 288 -for-linker
 289 Driver Separate Alias(Xlinker)
 290
 291 -for-linker=
 292 Driver JoinedOrMissing Alias(Xlinker)
 293
 294 -force-link
 295 Driver Separate Alias(u)
 296
 297 -force-link=
 298 Driver Joined Alias(u)
 299
 300 -help
 301 Common Driver Var(help_flag)
 302 Display this information.
 303
 304 -help=
 305 Common Driver Report Joined
 306 --help=<class>  Display descriptions of a specific class of options.  <class> is one or more of optimizers, target, warnings, undocumented, params.
 307
 308 -language
 309 Driver Separate Alias(x)
 310
 311 -language=
 312 Driver Joined Alias(x)
 313
 314 -library-directory
 315 Driver Separate Alias(L)
 316
 317 -library-directory=
 318 Driver Joined Alias(L)
 319
 320 -no-canonical-prefixes
 321 Driver Alias(no-canonical-prefixes)
 322
 323 -no-standard-libraries
 324 Driver Alias(nostdlib)
 325
 326 -no-sysroot-suffix
 327 Driver Var(no_sysroot_suffix)
 328
 329 -no-warnings
 330 Common Alias(w)
 331
 332 -optimize
 333 Common Alias(O)
 334
 335 -output
 336 Common Driver Separate Alias(o) MissingArgError(missing filename after %qs)
 337
 338 -output=
 339 Common Driver Joined Alias(o) MissingArgError(missing filename after %qs)
 340
 341 -pass-exit-codes
 342 Driver Alias(pass-exit-codes)
 343
 344 -pedantic
 345 Common Alias(Wpedantic)
 346
 347 -pedantic-errors
 348 Common Alias(pedantic-errors)
 349
 350 -pie
 351 Driver Alias(pie)
 352
 353 -pipe
 354 Driver Alias(pipe)
 355
 356 -prefix
 357 Driver Separate Alias(B)
 358
 359 -prefix=
 360 Driver JoinedOrMissing Alias(B)
 361
 362 -preprocess
 363 Driver Alias(E)
 364
 365 -print-file-name
 366 Driver Separate Alias(print-file-name=)
 367
 368 -print-file-name=
 369 Driver JoinedOrMissing Alias(print-file-name=)
 370
 371 -print-libgcc-file-name
 372 Driver Alias(print-libgcc-file-name)
 373
 374 -print-multi-directory
 375 Driver Alias(print-multi-directory)
 376
 377 -print-multi-lib
 378 Driver Alias(print-multi-lib)
 379
 380 -print-multi-os-directory
 381 Driver Alias(print-multi-os-directory)
 382
 383 -print-multiarch
 384 Driver Alias(print-multiarch)
 385
 386 -print-prog-name
 387 Driver Separate Alias(print-prog-name=)
 388
 389 -print-prog-name=
 390 Driver JoinedOrMissing Alias(print-prog-name=)
 391
 392 -print-search-dirs
 393 Driver Alias(print-search-dirs)
 394
 395 -print-sysroot
 396 Driver Alias(print-sysroot)
 397
 398 -print-sysroot-headers-suffix
 399 Driver Alias(print-sysroot-headers-suffix)
 400
 401 -profile
 402 Common Alias(p)
 403
 404 -save-temps
 405 Driver Alias(save-temps)
 406
 407 -shared
 408 Driver Alias(shared)
 409
 410 -specs
 411 Driver Separate Alias(specs=)
 412
 413 -specs=
 414 Driver Joined Alias(specs=)
 415
 416 -static
 417 Driver Alias(static)
 418
 419 -symbolic
 420 Driver Alias(symbolic)
 421
 422 -target-help
 423 Common Driver
 424 Alias for --help=target.
 425
 426 -time
 427 Driver Alias(time)
 428
 429 -verbose
 430 Driver Alias(v)
 431
 432 ;; The driver used to convert options such as --help into forms such
 433 ;; as -fhelp; the following four entries are for compatibility with
 434 ;; any direct uses of those (undocumented) -f forms
 435 fhelp
 436 Common Driver Alias(-help)
 437
 438 fhelp=
 439 Common Driver Joined Alias(-help=)
 440
 441 ftarget-help
 442 Common Driver Alias(-target-help)
 443
 444 fversion
 445 Common Driver Alias(-version)
 446
 447 -param
 448 Common Separate
 449 --param <param>=<value> Set parameter <param> to value.  See below for a complete list of parameters.
 450
 451 -param=
 452 Common Joined Alias(-param)
 453
 454 -sysroot
 455 Driver Separate Alias(-sysroot=)
 456
 457 -sysroot=
 458 Driver JoinedOrMissing
 459
 460 -version
 461 Common Driver
 462
 463 B
 464 Driver Joined Separate
 465
 466 E
 467 Driver
 468
 469 L
 470 Driver Joined Separate
 471
 472 N
 473 Driver
 474
 475 O
 476 Common JoinedOrMissing Optimization
 477 -O<number>      Set optimization level to <number>.
 478
 479 Os
 480 Common Optimization
 481 Optimize for space rather than speed.
 482
 483 Ofast
 484 Common Optimization
 485 Optimize for speed disregarding exact standards compliance.
 486
 487 Og
 488 Common Optimization
 489 Optimize for debugging experience rather than speed or size.
 490
 491 Q
 492 Driver
 493
 494 Qn
 495 Driver Negative(Qy)
 496
 497 Qy
 498 Driver Negative(Qn)
 499
 500 R
 501 Driver Joined Separate
 502
 503 S
 504 Driver
 505
 506 T
 507 Driver Joined Separate
 508
 509 Tbss
 510 Driver Separate
 511
 512 Tbss=
 513 Driver Joined
 514
 515 Tdata
 516 Driver Separate
 517
 518 Tdata=
 519 Driver Joined
 520
 521 Ttext
 522 Driver Separate
 523
 524 Ttext=
 525 Driver Joined
 526
 527 W
 528 Common RejectNegative Warning Alias(Wextra)
 529 This switch is deprecated; use -Wextra instead.
 530
 531 Wa,
 532 Driver JoinedOrMissing
 533
 534 Wl,
 535 Driver JoinedOrMissing
 536
 537 Wp,
 538 Driver JoinedOrMissing
 539
 540 Waggregate-return
 541 Common Var(warn_aggregate_return) Warning
 542 Warn about returning structures, unions or arrays.
 543
 544 Waggressive-loop-optimizations
 545 Common Var(warn_aggressive_loop_optimizations) Init(1) Warning
 546 Warn if a loop with constant number of iterations triggers undefined behavior.
 547
 548 Warray-bounds
 549 Common Var(warn_array_bounds) Warning
 550 Warn if an array is accessed out of bounds.
 551
 552 Warray-bounds=
 553 Common Joined RejectNegative UInteger Var(warn_array_bounds) Warning
 554 Warn if an array is accessed out of bounds.
 555
 556 Wattributes
 557 Common Var(warn_attributes) Init(1) Warning
 558 Warn about inappropriate attribute usage.
 559
 560 Wcast-align
 561 Common Var(warn_cast_align) Warning
 562 Warn about pointer casts which increase alignment.
 563
 564 Wcpp
 565 Common Var(warn_cpp) Init(1) Warning
 566 Warn when a #warning directive is encountered.
 567
 568 Wdeprecated-declarations
 569 Common Var(warn_deprecated_decl) Init(1) Warning
 570 Warn about uses of __attribute__((deprecated)) declarations.
 571
 572 Wdisabled-optimization
 573 Common Var(warn_disabled_optimization) Warning
 574 Warn when an optimization pass is disabled.
 575
 576 Werror
 577 Common Var(warnings_are_errors)
 578 Treat all warnings as errors.
 579
 580 Werror=
 581 Common Joined
 582 Treat specified warning as error.
 583
 584 Wextra
 585 Common Var(extra_warnings) Warning
 586 Print extra (possibly unwanted) warnings.
 587
 588 Wfatal-errors
 589 Common Var(flag_fatal_errors)
 590 Exit on the first error occurred.
 591
 592 Wframe-larger-than=
 593 Common RejectNegative Joined UInteger Warning
 594 -Wframe-larger-than=<number>    Warn if a function's stack frame requires more than <number> bytes.
 595
 596 Wfree-nonheap-object
 597 Common Var(warn_free_nonheap_object) Init(1) Warning
 598 Warn when attempting to free a non-heap object.
 599
 600 Whsa
 601 Common Var(warn_hsa) Init(1) Warning
 602 Warn when a function cannot be expanded to HSAIL.
 603
 604 Wimplicit-fallthrough-disabled
 605 Common Var(warn_implicit_fallthrough) Warning
 606 Warn when a switch case falls through.
 607
 608 Winline
 609 Common Var(warn_inline) Warning
 610 Warn when an inlined function cannot be inlined.
 611
 612 Winvalid-memory-model
 613 Common Var(warn_invalid_memory_model) Init(1) Warning
 614 Warn when an atomic memory model parameter is known to be outside the valid range.
 615
 616 Wlarger-than-
 617 Common RejectNegative Joined Warning Undocumented Alias(Wlarger-than=)
 618
 619 Wlarger-than=
 620 Common RejectNegative Joined UInteger Warning
 621 -Wlarger-than=<number>  Warn if an object is larger than <number> bytes.
 622
 623 Wnonnull-compare
 624 Var(warn_nonnull_compare) Warning
 625 Warn if comparing pointer parameter with nonnull attribute with NULL.
 626
 627 Wnull-dereference
 628 Common Var(warn_null_dereference) Warning
 629 Warn if dereferencing a NULL pointer may lead to erroneous or undefined behavior.
 630
 631 Wunsafe-loop-optimizations
 632 Common Var(warn_unsafe_loop_optimizations) Warning
 633 Warn if the loop cannot be optimized due to nontrivial assumptions.
 634
 635 Wmissing-noreturn
 636 Common Warning Alias(Wsuggest-attribute=noreturn)
 637
 638 Wodr
 639 Common Var(warn_odr_violations) Init(1) Warning
 640 Warn about some C++ One Definition Rule violations during link time optimization.
 641
 642 Woverflow
 643 Common Var(warn_overflow) Init(1) Warning
 644 Warn about overflow in arithmetic expressions.
 645
 646 Wlto-type-mismatch
 647 Common Var(warn_lto_type_mismatch) Init(1) Warning
 648 During link time optimization warn about mismatched types of global declarations.
 649
 650 Wpacked
 651 Common Var(warn_packed) Warning
 652 Warn when the packed attribute has no effect on struct layout.
 653
 654 Wpadded
 655 Common Var(warn_padded) Warning
 656 Warn when padding is required to align structure members.
 657
 658 Wpedantic
 659 Common Var(pedantic) Init(0) Warning
 660 Issue warnings needed for strict compliance to the standard.
 661
 662 Wprint-abs-path
 663 Common Var(flag_source_abs_path) Init(0)
 664 Print a absolute path to the source file.
 665
 666 Wreturn-local-addr
 667 Common Var(warn_return_local_addr) Init(1) Warning
 668 Warn about returning a pointer/reference to a local or temporary variable.
 669
 670 Wshadow
 671 Common Var(warn_shadow) Warning
 672 Warn when one local variable shadows another.
 673
 674 Wstack-protector
 675 Common Var(warn_stack_protect) Warning
 676 Warn when not issuing stack smashing protection for some reason.
 677
 678 Wstack-usage=
 679 Common Joined RejectNegative UInteger Var(warn_stack_usage) Init(-1) Warning
 680 Warn if stack usage might be larger than specified amount.
 681
 682 Wstrict-aliasing
 683 Common Warning
 684 Warn about code which might break strict aliasing rules.
 685
 686 Wstrict-aliasing=
 687 Common Joined RejectNegative UInteger Var(warn_strict_aliasing) Warning
 688 Warn about code which might break strict aliasing rules.
 689
 690 Wstrict-overflow
 691 Common Warning
 692 Warn about optimizations that assume that signed overflow is undefined.
 693
 694 Wstrict-overflow=
 695 Common Joined RejectNegative UInteger Var(warn_strict_overflow) Warning
 696 Warn about optimizations that assume that signed overflow is undefined.
 697
 698 Wsuggest-attribute=const
 699 Common Var(warn_suggest_attribute_const) Warning
 700 Warn about functions which might be candidates for __attribute__((const)).
 701
 702 Wsuggest-attribute=pure
 703 Common Var(warn_suggest_attribute_pure) Warning
 704 Warn about functions which might be candidates for __attribute__((pure)).
 705
 706 Wsuggest-attribute=noreturn
 707 Common Var(warn_suggest_attribute_noreturn) Warning
 708 Warn about functions which might be candidates for __attribute__((noreturn)).
 709
 710 Wsuggest-final-types
 711 Common Var(warn_suggest_final_types) Warning
 712 Warn about C++ polymorphic types where adding final keyword would improve code quality.
 713
 714 Wsuggest-final-methods
 715 Common Var(warn_suggest_final_methods) Warning
 716 Warn about C++ virtual methods where adding final keyword would improve code quality.
 717
 718 Wswitch-unreachable
 719 Common Var(warn_switch_unreachable) Warning EnabledBy(Wextra)
 720 Warn about statements between switch's controlling expression and the first
 721 case.
 722
 723 Wsystem-headers
 724 Common Var(warn_system_headers) Warning
 725 Do not suppress warnings from system headers.
 726
 727 Wtrampolines
 728 Common Var(warn_trampolines) Warning
 729 Warn whenever a trampoline is generated.
 730
 731 Wtype-limits
 732 Common Var(warn_type_limits) Warning EnabledBy(Wextra)
 733 Warn if a comparison is always true or always false due to the limited range of the data type.
 734
 735 Wuninitialized
 736 Common Var(warn_uninitialized) Warning EnabledBy(Wextra)
 737 Warn about uninitialized automatic variables.
 738
 739 Wmaybe-uninitialized
 740 Common Var(warn_maybe_uninitialized) Warning EnabledBy(Wuninitialized)
 741 Warn about maybe uninitialized automatic variables.
 742
 743 Wunreachable-code
 744 Common Ignore Warning
 745 Does nothing. Preserved for backward compatibility.
 746
 747 Wunused
 748 Common Var(warn_unused) Init(0) Warning
 749 Enable all -Wunused- warnings.
 750
 751 Wunused-but-set-parameter
 752 Common Var(warn_unused_but_set_parameter) Warning EnabledBy(Wunused && Wextra)
 753 Warn when a function parameter is only set, otherwise unused.
 754
 755 Wunused-but-set-variable
 756 Common Var(warn_unused_but_set_variable) Warning EnabledBy(Wunused)
 757 Warn when a variable is only set, otherwise unused.
 758
 759 Wunused-function
 760 Common Var(warn_unused_function) Warning EnabledBy(Wunused)
 761 Warn when a function is unused.
 762
 763 Wunused-label
 764 Common Var(warn_unused_label) Warning EnabledBy(Wunused)
 765 Warn when a label is unused.
 766
 767 Wunused-parameter
 768 Common Var(warn_unused_parameter) Warning EnabledBy(Wunused && Wextra)
 769 Warn when a function parameter is unused.
 770
 771 Wunused-value
 772 Common Var(warn_unused_value) Warning EnabledBy(Wunused)
 773 Warn when an expression value is unused.
 774
 775 Wunused-variable
 776 Common Var(warn_unused_variable) Warning EnabledBy(Wunused)
 777 Warn when a variable is unused.
 778
 779 Wcoverage-mismatch
 780 Common Var(warn_coverage_mismatch) Init(1) Warning
 781 Warn in case profiles in -fprofile-use do not match.
 782
 783 Wvector-operation-performance
 784 Common Var(warn_vector_operation_performance) Warning
 785 Warn when a vector operation is compiled outside the SIMD.
 786
 787 Xassembler
 788 Driver Separate
 789
 790 Xlinker
 791 Driver Separate
 792
 793 Xpreprocessor
 794 Driver Separate
 795
 796 Z
 797 Driver
 798
 799 aux-info
 800 Common Separate Var(aux_info_file_name)
 801 -aux-info <file>        Emit declaration information into <file>.
 802
 803 aux-info=
 804 Common Joined Alias(aux-info)
 805
 806 auxbase
 807 Common Separate RejectDriver Var(aux_base_name)
 808
 809 auxbase-strip
 810 Common Separate RejectDriver
 811
 812 coverage
 813 Driver
 814
 815 c
 816 Driver
 817
 818 d
 819 Common Joined
 820 -d<letters>     Enable dumps from specific passes of the compiler.
 821
 822 dumpbase
 823 Common Separate Var(dump_base_name)
 824 -dumpbase <file>        Set the file basename to be used for dumps.
 825
 826 dumpdir
 827 Common Separate Var(dump_dir_name)
 828 -dumpdir <dir>  Set the directory name to be used for dumps.
 829
 830 dumpmachine
 831 Driver
 832
 833 dumpspecs
 834 Driver
 835
 836 dumpversion
 837 Driver
 838
 839 e
 840 Driver Joined Separate
 841
 842 ; This option has historically been passed down to the linker by an
 843 ; accident of a %{e*} spec, so ensure it continues to be passed down
 844 ; as a single option.  The supported option for this purpose is
 845 ; -rdynamic.  See PR 47390.
 846 export-dynamic
 847 Driver Undocumented
 848
 849 ; The version of the C++ ABI in use.  The following values are allowed:
 850 ;
 851 ; 0: The version of the ABI believed most conformant with the C++ ABI
 852 ;    specification.  This ABI may change as bugs are discovered and fixed.
 853 ;    Therefore, 0 will not necessarily indicate the same ABI in different
 854 ;    versions of G++.
 855 ;
 856 ; 1: The version of the ABI first used in G++ 3.2.  No longer selectable.
 857 ;
 858 ; 2: The version of the ABI first used in G++ 3.4, and the default
 859 ;    until GCC 4.9.
 860 ;
 861 ; 3: The version of the ABI that fixes the missing underscore
 862 ;    in template non-type arguments of pointer type.
 863 ;
 864 ; 4: The version of the ABI that introduces unambiguous mangling of
 865 ;    vector types.  First selectable in G++ 4.5.
 866 ;
 867 ; 5: The version of the ABI that ignores attribute const/noreturn
 868 ;    in function pointer mangling, and corrects mangling of decltype and
 869 ;    function parameters used in other parameters and the return type.
 870 ;    First selectable in G++ 4.6.
 871 ;
 872 ; 6: The version of the ABI that doesn't promote scoped enums to int and
 873 ;    changes the mangling of template argument packs, const/static_cast,
 874 ;    prefix ++ and --, and a class scope function used as a template
 875 ;    argument.
 876 ;    First selectable in G++ 4.7.
 877 ;
 878 ; 7: The version of the ABI that treats nullptr_t as a builtin type and
 879 ;    corrects the mangling of lambdas in default argument scope.
 880 ;    First selectable in G++ 4.8.
 881 ;
 882 ; 8: The version of the ABI that corrects the substitution behavior of
 883 ;    function types with function-cv-qualifiers.
 884 ;    First selectable in G++ 4.9 and default in G++ 5.
 885 ;
 886 ; 9: The version of the ABI that corrects the alignment of nullptr_t.
 887 ;    First selectable and default in G++ 5.2.
 888 ;
 889 ; 10: The version of the ABI that mangles attributes that affect type
 890 ;     identity, such as ia32 calling convention attributes (stdcall, etc.)
 891 ;     Default in G++ 6 (set in c_common_post_options).
 892 ;
 893 ; Additional positive integers will be assigned as new versions of
 894 ; the ABI become the default version of the ABI.
 895 fabi-version=
 896 Common Joined RejectNegative UInteger Var(flag_abi_version) Init(0)
 897 The version of the C++ ABI in use.
 898
 899 faggressive-loop-optimizations
 900 Common Report Var(flag_aggressive_loop_optimizations) Optimization Init(1)
 901 Aggressively optimize loops using language constraints.
 902
 903 falign-functions
 904 Common Report Var(align_functions,0) Optimization UInteger
 905 Align the start of functions.
 906
 907 falign-functions=
 908 Common RejectNegative Joined UInteger Var(align_functions)
 909
 910 falign-jumps
 911 Common Report Var(align_jumps,0) Optimization UInteger
 912 Align labels which are only reached by jumping.
 913
 914 falign-jumps=
 915 Common RejectNegative Joined UInteger Var(align_jumps)
 916
 917 falign-labels
 918 Common Report Var(align_labels,0) Optimization UInteger
 919 Align all labels.
 920
 921 falign-labels=
 922 Common RejectNegative Joined UInteger Var(align_labels)
 923
 924 falign-loops
 925 Common Report Var(align_loops,0) Optimization UInteger
 926 Align the start of loops.
 927
 928 falign-loops=
 929 Common RejectNegative Joined UInteger Var(align_loops)
 930
 931 fargument-alias
 932 Common Ignore
 933 Does nothing. Preserved for backward compatibility.
 934
 935 fargument-noalias
 936 Common Ignore
 937 Does nothing. Preserved for backward compatibility.
 938
 939 fargument-noalias-global
 940 Common Ignore
 941 Does nothing. Preserved for backward compatibility.
 942
 943 fargument-noalias-anything
 944 Common Ignore
 945 Does nothing. Preserved for backward compatibility.
 946
 947 fsanitize=
 948 Common Driver Report Joined
 949 Select what to sanitize.
 950
 951 fasan-shadow-offset=
 952 Common Joined RejectNegative Var(common_deferred_options) Defer
 953 -fasan-shadow-offset=<number>   Use custom shadow memory offset.
 954
 955 fsanitize-sections=
 956 Common Joined RejectNegative Var(common_deferred_options) Defer
 957 -fsanitize-sections=<sec1,sec2,...>     Sanitize global variables
 958 in user-defined sections.
 959
 960 fsanitize-recover=
 961 Common Report Joined
 962 After diagnosing undefined behavior attempt to continue execution.
 963
 964 fsanitize-recover
 965 Common Report
 966 This switch is deprecated; use -fsanitize-recover= instead.
 967
 968 fsanitize-address-use-after-scope
 969 Common Driver Report Var(flag_sanitize_address_use_after_scope) Init(0)
 970
 971 fsanitize-undefined-trap-on-error
 972 Common Driver Report Var(flag_sanitize_undefined_trap_on_error) Init(0)
 973 Use trap instead of a library function for undefined behavior sanitization.
 974
 975 fasynchronous-unwind-tables
 976 Common Report Var(flag_asynchronous_unwind_tables) Optimization
 977 Generate unwind tables that are exact at each instruction boundary.
 978
 979 fauto-inc-dec
 980 Common Report Var(flag_auto_inc_dec) Init(1) Optimization
 981 Generate auto-inc/dec instructions.
 982
 983 fauto-profile
 984 Common Report Var(flag_auto_profile)
 985 Use sample profile information for call graph node weights. The default
 986 profile file is fbdata.afdo in 'pwd'.
 987
 988 fauto-profile=
 989 Common Joined RejectNegative Var(auto_profile_file)
 990 Use sample profile information for call graph node weights. The profile
 991 file is specified in the argument.
 992
 993 ; -fcheck-bounds causes gcc to generate array bounds checks.
 994 ; For C, C++ and ObjC: defaults off.
 995 ; For Java: defaults to on.
 996 ; For Fortran: defaults to off.
 997 fbounds-check
 998 Common Report Var(flag_bounds_check)
 999 Generate code to check bounds before indexing arrays.
1000
1001 fbranch-count-reg
1002 Common Report Var(flag_branch_on_count_reg) Optimization
1003 Replace add, compare, branch with branch on count register.
1004
1005 fbranch-probabilities
1006 Common Report Var(flag_branch_probabilities) Optimization
1007 Use profiling information for branch probabilities.
1008
1009 fbranch-target-load-optimize
1010 Common Report Var(flag_branch_target_load_optimize) Optimization
1011 Perform branch target load optimization before prologue / epilogue threading.
1012
1013 fbranch-target-load-optimize2
1014 Common Report Var(flag_branch_target_load_optimize2) Optimization
1015 Perform branch target load optimization after prologue / epilogue threading.
1016
1017 fbtr-bb-exclusive
1018 Common Report Var(flag_btr_bb_exclusive) Optimization
1019 Restrict target load migration not to re-use registers in any basic block.
1020
1021 fcall-saved-
1022 Common Joined RejectNegative Var(common_deferred_options) Defer
1023 -fcall-saved-<register> Mark <register> as being preserved across functions.
1024
1025 fcall-used-
1026 Common Joined RejectNegative Var(common_deferred_options) Defer
1027 -fcall-used-<register>  Mark <register> as being corrupted by function calls.
1028
1029 ; Nonzero for -fcaller-saves: allocate values in regs that need to
1030 ; be saved across function calls, if that produces overall better code.
1031 ; Optional now, so people can test it.
1032 fcaller-saves
1033 Common Report Var(flag_caller_saves) Optimization
1034 Save registers around function calls.
1035
1036 fcheck-data-deps
1037 Common Report Var(flag_check_data_deps)
1038 This switch is deprecated; do not use.
1039
1040 fcheck-new
1041 Common Var(flag_check_new)
1042 Check the return value of new in C++.
1043
1044 fchecking
1045 Common Var(flag_checking) Init(CHECKING_P)
1046 Perform internal consistency checkings.
1047
1048 fcombine-stack-adjustments
1049 Common Report Var(flag_combine_stack_adjustments) Optimization
1050 Looks for opportunities to reduce stack adjustments and stack references.
1051
1052 fcommon
1053 Common Report Var(flag_no_common,0)
1054 Do not put uninitialized globals in the common section.
1055
1056 fcompare-debug
1057 Driver
1058 ; Converted by the driver to -fcompare-debug= options.
1059
1060 fcompare-debug=
1061 Common Driver JoinedOrMissing RejectNegative Var(flag_compare_debug_opt)
1062 -fcompare-debug[=<opts>]        Compile with and without e.g. -gtoggle, and compare the final-insns dump.
1063
1064 fcompare-debug-second
1065 Common Driver RejectNegative Var(flag_compare_debug)
1066 Run only the second compilation of -fcompare-debug.
1067
1068 fcompare-elim
1069 Common Report Var(flag_compare_elim_after_reload) Optimization
1070 Perform comparison elimination after register allocation has finished.
1071
1072 fconserve-stack
1073 Common Var(flag_conserve_stack) Optimization
1074 Do not perform optimizations increasing noticeably stack usage.
1075
1076 fcprop-registers
1077 Common Report Var(flag_cprop_registers) Optimization
1078 Perform a register copy-propagation optimization pass.
1079
1080 fcrossjumping
1081 Common Report Var(flag_crossjumping) Optimization
1082 Perform cross-jumping optimization.
1083
1084 fcse-follow-jumps
1085 Common Report Var(flag_cse_follow_jumps) Optimization
1086 When running CSE, follow jumps to their targets.
1087
1088 fcse-skip-blocks
1089 Common Ignore
1090 Does nothing.  Preserved for backward compatibility.
1091
1092 fcx-limited-range
1093 Common Report Var(flag_cx_limited_range) Optimization SetByCombined
1094 Omit range reduction step when performing complex division.
1095
1096 fcx-fortran-rules
1097 Common Report Var(flag_cx_fortran_rules) Optimization
1098 Complex multiplication and division follow Fortran rules.
1099
1100 fdata-sections
1101 Common Report Var(flag_data_sections)
1102 Place data items into their own section.
1103
1104 fdbg-cnt-list
1105 Common Report Var(common_deferred_options) Defer
1106 List all available debugging counters with their limits and counts.
1107
1108 fdbg-cnt=
1109 Common RejectNegative Joined Var(common_deferred_options) Defer
1110 -fdbg-cnt=<counter>:<limit>[,<counter>:<limit>,...]     Set the debug counter limit.
1111
1112 fdebug-prefix-map=
1113 Common Joined RejectNegative Var(common_deferred_options) Defer
1114 Map one directory name to another in debug information.
1115
1116 fdebug-types-section
1117 Common Report Var(flag_debug_types_section) Init(0)
1118 Output .debug_types section when using DWARF v4 debuginfo.
1119
1120 ; Nonzero for -fdefer-pop: don't pop args after each function call
1121 ; instead save them up to pop many calls' args with one insns.
1122 fdefer-pop
1123 Common Report Var(flag_defer_pop) Optimization
1124 Defer popping functions args from stack until later.
1125
1126 fdelayed-branch
1127 Common Report Var(flag_delayed_branch) Optimization
1128 Attempt to fill delay slots of branch instructions.
1129
1130 fdelete-dead-exceptions
1131 Common Report Var(flag_delete_dead_exceptions) Init(0) Optimization
1132 Delete dead instructions that may throw exceptions.
1133
1134 fdelete-null-pointer-checks
1135 Common Report Var(flag_delete_null_pointer_checks) Init(-1) Optimization
1136 Delete useless null pointer checks.
1137
1138 fdevirtualize-at-ltrans
1139 Common Report Var(flag_ltrans_devirtualize)
1140 Stream extra data to support more aggressive devirtualization in LTO local transformation mode.
1141
1142 fdevirtualize-speculatively
1143 Common Report Var(flag_devirtualize_speculatively) Optimization
1144 Perform speculative devirtualization.
1145
1146 fdevirtualize
1147 Common Report Var(flag_devirtualize) Optimization
1148 Try to convert virtual calls to direct ones.
1149
1150 fdiagnostics-show-location=
1151 Common Joined RejectNegative Enum(diagnostic_prefixing_rule)
1152 -fdiagnostics-show-location=[once|every-line]   How often to emit source location at the beginning of line-wrapped diagnostics.
1153
1154 ; Required for these enum values.
1155 SourceInclude
1156 pretty-print.h
1157
1158 Enum
1159 Name(diagnostic_prefixing_rule) Type(int)
1160
1161 EnumValue
1162 Enum(diagnostic_prefixing_rule) String(once) Value(DIAGNOSTICS_SHOW_PREFIX_ONCE)
1163
1164 EnumValue
1165 Enum(diagnostic_prefixing_rule) String(every-line) Value(DIAGNOSTICS_SHOW_PREFIX_EVERY_LINE)
1166
1167 fdiagnostics-show-caret
1168 Common Var(flag_diagnostics_show_caret) Init(1)
1169 Show the source line with a caret indicating the column.
1170
1171 fdiagnostics-color
1172 Common Alias(fdiagnostics-color=,always,never)
1173 ;
1174
1175 fdiagnostics-color=
1176 Driver Common Joined RejectNegative Var(flag_diagnostics_show_color) Enum(diagnostic_color_rule) Init(DIAGNOSTICS_COLOR_NO)
1177 -fdiagnostics-color=[never|always|auto] Colorize diagnostics.
1178
1179 ; Required for these enum values.
1180 SourceInclude
1181 diagnostic-color.h
1182
1183 Enum
1184 Name(diagnostic_color_rule) Type(int)
1185
1186 EnumValue
1187 Enum(diagnostic_color_rule) String(never) Value(DIAGNOSTICS_COLOR_NO)
1188
1189 EnumValue
1190 Enum(diagnostic_color_rule) String(always) Value(DIAGNOSTICS_COLOR_YES)
1191
1192 EnumValue
1193 Enum(diagnostic_color_rule) String(auto) Value(DIAGNOSTICS_COLOR_AUTO)
1194
1195 fdiagnostics-show-option
1196 Common Var(flag_diagnostics_show_option) Init(1)
1197 Amend appropriate diagnostic messages with the command line option that controls them.
1198
1199 fdisable-
1200 Common Joined RejectNegative Var(common_deferred_options) Defer
1201 -fdisable-[tree|rtl|ipa]-<pass>=range1+range2 disables an optimization pass.
1202
1203 fenable-
1204 Common Joined RejectNegative Var(common_deferred_options) Defer
1205 -fenable-[tree|rtl|ipa]-<pass>=range1+range2 enables an optimization pass.
1206
1207 fdump-
1208 Common Joined RejectNegative Var(common_deferred_options) Defer
1209 -fdump-<type>   Dump various compiler internals to a file.
1210
1211 fdump-final-insns
1212 Driver RejectNegative
1213
1214 fdump-final-insns=
1215 Common RejectNegative Joined Var(flag_dump_final_insns)
1216 -fdump-final-insns=filename     Dump to filename the insns at the end of translation.
1217
1218 fdump-go-spec=
1219 Common RejectNegative Joined Var(flag_dump_go_spec)
1220 -fdump-go-spec=filename Write all declarations to file as Go code.
1221
1222 fdump-noaddr
1223 Common Report Var(flag_dump_noaddr)
1224 Suppress output of addresses in debugging dumps.
1225
1226 freport-bug
1227 Common Driver Var(flag_report_bug)
1228 Collect and dump debug information into temporary file if ICE in C/C++
1229 compiler occured.
1230
1231 fdump-internal-locations
1232 Common Var(flag_dump_locations) Init(0)
1233 Dump detailed information on GCC's internal representation of source code locations.
1234
1235 fdump-passes
1236 Common Var(flag_dump_passes) Init(0)
1237 Dump optimization passes.
1238
1239 fdump-unnumbered
1240 Common Report Var(flag_dump_unnumbered)
1241 Suppress output of instruction numbers, line number notes and addresses in debugging dumps.
1242
1243 fdump-unnumbered-links
1244 Common Report Var(flag_dump_unnumbered_links)
1245 Suppress output of previous and next insn numbers in debugging dumps.
1246
1247 fdwarf2-cfi-asm
1248 Common Report Var(flag_dwarf2_cfi_asm) Init(HAVE_GAS_CFI_DIRECTIVE)
1249 Enable CFI tables via GAS assembler directives.
1250
1251 fearly-inlining
1252 Common Report Var(flag_early_inlining) Init(1) Optimization
1253 Perform early inlining.
1254
1255 feliminate-dwarf2-dups
1256 Common Report Var(flag_eliminate_dwarf2_dups)
1257 Perform DWARF duplicate elimination.
1258
1259 fipa-sra
1260 Common Report Var(flag_ipa_sra) Init(0) Optimization
1261 Perform interprocedural reduction of aggregates.
1262
1263 feliminate-unused-debug-symbols
1264 Common Report Var(flag_debug_only_used_symbols)
1265 Perform unused symbol elimination in debug info.
1266
1267 feliminate-unused-debug-types
1268 Common Report Var(flag_eliminate_unused_debug_types) Init(1)
1269 Perform unused type elimination in debug info.
1270
1271 femit-class-debug-always
1272 Common Report Var(flag_emit_class_debug_always) Init(0)
1273 Do not suppress C++ class debug information.
1274
1275 fexceptions
1276 Common Report Var(flag_exceptions) Optimization
1277 Enable exception handling.
1278
1279 fexpensive-optimizations
1280 Common Report Var(flag_expensive_optimizations) Optimization
1281 Perform a number of minor, expensive optimizations.
1282
1283 fexcess-precision=
1284 Common Joined RejectNegative Enum(excess_precision) Var(flag_excess_precision_cmdline) Init(EXCESS_PRECISION_DEFAULT)
1285 -fexcess-precision=[fast|standard]      Specify handling of excess floating-point precision.
1286
1287 Enum
1288 Name(excess_precision) Type(enum excess_precision) UnknownError(unknown excess precision style %qs)
1289
1290 EnumValue
1291 Enum(excess_precision) String(fast) Value(EXCESS_PRECISION_FAST)
1292
1293 EnumValue
1294 Enum(excess_precision) String(standard) Value(EXCESS_PRECISION_STANDARD)
1295
1296 ffast-math
1297 Common
1298
1299 ffat-lto-objects
1300 Common Var(flag_fat_lto_objects)
1301 Output lto objects containing both the intermediate language and binary output.
1302
1303 ffinite-math-only
1304 Common Report Var(flag_finite_math_only) Optimization SetByCombined
1305 Assume no NaNs or infinities are generated.
1306
1307 ffixed-
1308 Common Joined RejectNegative Var(common_deferred_options) Defer
1309 -ffixed-<register>      Mark <register> as being unavailable to the compiler.
1310
1311 ffloat-store
1312 Common Report Var(flag_float_store) Optimization
1313 Don't allocate floats and doubles in extended-precision registers.
1314
1315 fforce-addr
1316 Common Ignore
1317 Does nothing.  Preserved for backward compatibility.
1318
1319 fforward-propagate
1320 Common Report Var(flag_forward_propagate) Optimization
1321 Perform a forward propagation pass on RTL.
1322
1323 ffp-contract=
1324 Common Joined RejectNegative Enum(fp_contract_mode) Var(flag_fp_contract_mode) Init(FP_CONTRACT_FAST) Optimization
1325 -ffp-contract=[off|on|fast] Perform floating-point expression contraction.
1326
1327 Enum
1328 Name(fp_contract_mode) Type(enum fp_contract_mode) UnknownError(unknown floating point contraction style %qs)
1329
1330 EnumValue
1331 Enum(fp_contract_mode) String(off) Value(FP_CONTRACT_OFF)
1332
1333 ; Not implemented, fall back to conservative FP_CONTRACT_OFF.
1334 EnumValue
1335 Enum(fp_contract_mode) String(on) Value(FP_CONTRACT_OFF)
1336
1337 EnumValue
1338 Enum(fp_contract_mode) String(fast) Value(FP_CONTRACT_FAST)
1339
1340 ; Nonzero means don't put addresses of constant functions in registers.
1341 ; Used for compiling the Unix kernel, where strange substitutions are
1342 ; done on the assembly output.
1343 ffunction-cse
1344 Common Report Var(flag_no_function_cse,0) Optimization
1345 Allow function addresses to be held in registers.
1346
1347 ffunction-sections
1348 Common Report Var(flag_function_sections)
1349 Place each function into its own section.
1350
1351 fgcse
1352 Common Report Var(flag_gcse) Optimization
1353 Perform global common subexpression elimination.
1354
1355 fgcse-lm
1356 Common Report Var(flag_gcse_lm) Init(1) Optimization
1357 Perform enhanced load motion during global common subexpression elimination.
1358
1359 fgcse-sm
1360 Common Report Var(flag_gcse_sm) Init(0) Optimization
1361 Perform store motion after global common subexpression elimination.
1362
1363 fgcse-las
1364 Common Report Var(flag_gcse_las) Init(0) Optimization
1365 Perform redundant load after store elimination in global common subexpression
1366 elimination.
1367
1368 fgcse-after-reload
1369 Common Report Var(flag_gcse_after_reload) Optimization
1370 Perform global common subexpression elimination after register allocation has
1371 finished.
1372
1373 Enum
1374 Name(dwarf_gnat_encodings) Type(int)
1375
1376 EnumValue
1377 Enum(dwarf_gnat_encodings) String(all) Value(DWARF_GNAT_ENCODINGS_ALL)
1378
1379 EnumValue
1380 Enum(dwarf_gnat_encodings) String(gdb) Value(DWARF_GNAT_ENCODINGS_GDB)
1381
1382 EnumValue
1383 Enum(dwarf_gnat_encodings) String(minimal) Value(DWARF_GNAT_ENCODINGS_MINIMAL)
1384
1385 fgnat-encodings=
1386 Common Enum(dwarf_gnat_encodings) Joined RejectNegative Report Undocumented Var(gnat_encodings)
1387 -fgnat-encodings=[all|gdb|minimal]      Select the balance between GNAT encodings and standard DWARF emitted in the debug information
1388
1389 ; This option is not documented yet as its semantics will change.
1390 fgraphite
1391 Common Report Var(flag_graphite) Optimization
1392 Enable in and out of Graphite representation.
1393
1394 fgraphite-identity
1395 Common Report Var(flag_graphite_identity) Optimization
1396 Enable Graphite Identity transformation.
1397
1398 fhoist-adjacent-loads
1399 Common Report Var(flag_hoist_adjacent_loads) Optimization
1400 Enable hoisting adjacent loads to encourage generating conditional move
1401 instructions.
1402
1403 fkeep-gc-roots-live
1404 Common Undocumented Report Var(flag_keep_gc_roots_live) Optimization
1405 ; Always keep a pointer to a live memory block
1406
1407 floop-parallelize-all
1408 Common Report Var(flag_loop_parallelize_all) Optimization
1409 Mark all loops as parallel.
1410
1411 floop-strip-mine
1412 Common Alias(floop-nest-optimize)
1413 Enable loop nest transforms.  Same as -floop-nest-optimize.
1414
1415 floop-interchange
1416 Common Alias(floop-nest-optimize)
1417 Enable loop nest transforms.  Same as -floop-nest-optimize.
1418
1419 floop-block
1420 Common Alias(floop-nest-optimize)
1421 Enable loop nest transforms.  Same as -floop-nest-optimize.
1422
1423 floop-unroll-and-jam
1424 Common Alias(floop-nest-optimize)
1425 Enable loop nest transforms.  Same as -floop-nest-optimize.
1426
1427 fgnu-tm
1428 Common Report Var(flag_tm)
1429 Enable support for GNU transactional memory.
1430
1431 fgnu-unique
1432 Common Report Var(flag_gnu_unique) Init(1)
1433 Use STB_GNU_UNIQUE if supported by the assembler.
1434
1435 floop-flatten
1436 Common Ignore
1437 Does nothing. Preserved for backward compatibility.
1438
1439 floop-nest-optimize
1440 Common Report Var(flag_loop_nest_optimize) Optimization
1441 Enable the loop nest optimizer.
1442
1443 fstrict-volatile-bitfields
1444 Common Report Var(flag_strict_volatile_bitfields) Init(-1) Optimization
1445 Force bitfield accesses to match their type width.
1446
1447 fguess-branch-probability
1448 Common Report Var(flag_guess_branch_prob) Optimization
1449 Enable guessing of branch probabilities.
1450
1451 ; Nonzero means ignore `#ident' directives.  0 means handle them.
1452 ; Generate position-independent code for executables if possible
1453 ; On SVR4 targets, it also controls whether or not to emit a
1454 ; string identifying the compiler.
1455 fident
1456 Common Report Var(flag_no_ident,0)
1457 Process #ident directives.
1458
1459 fif-conversion
1460 Common Report Var(flag_if_conversion) Optimization
1461 Perform conversion of conditional jumps to branchless equivalents.
1462
1463 fif-conversion2
1464 Common Report Var(flag_if_conversion2) Optimization
1465 Perform conversion of conditional jumps to conditional execution.
1466
1467 fstack-reuse=
1468 Common Joined RejectNegative Enum(stack_reuse_level) Var(flag_stack_reuse) Init(SR_ALL) Optimization
1469 -fstack-reuse=[all|named_vars|none] Set stack reuse level for local variables.
1470
1471 Enum
1472 Name(stack_reuse_level) Type(enum stack_reuse_level) UnknownError(unknown Stack Reuse Level %qs)
1473
1474 EnumValue
1475 Enum(stack_reuse_level) String(all) Value(SR_ALL)
1476
1477 EnumValue
1478 Enum(stack_reuse_level) String(named_vars) Value(SR_NAMED_VARS)
1479
1480 EnumValue
1481 Enum(stack_reuse_level) String(none) Value(SR_NONE)
1482
1483 ftree-loop-if-convert
1484 Common Report Var(flag_tree_loop_if_convert) Init(-1) Optimization
1485 Convert conditional jumps in innermost loops to branchless equivalents.
1486
1487 ftree-loop-if-convert-stores
1488 Common Report Var(flag_tree_loop_if_convert_stores) Optimization
1489 Also if-convert conditional jumps containing memory writes.
1490
1491 ; -finhibit-size-directive inhibits output of .size for ELF.
1492 ; This is used only for compiling crtstuff.c,
1493 ; and it may be extended to other effects
1494 ; needed for crtstuff.c on other systems.
1495 finhibit-size-directive
1496 Common Report Var(flag_inhibit_size_directive)
1497 Do not generate .size directives.
1498
1499 findirect-inlining
1500 Common Report Var(flag_indirect_inlining) Optimization
1501 Perform indirect inlining.
1502
1503 ; General flag to enable inlining.  Specifying -fno-inline will disable
1504 ; all inlining apart from always-inline functions.
1505 finline
1506 Common Report Var(flag_no_inline,0) Init(0) Optimization
1507 Enable inlining of function declared \"inline\", disabling disables all inlining.
1508
1509 finline-small-functions
1510 Common Report Var(flag_inline_small_functions) Optimization
1511 Integrate functions into their callers when code size is known not to grow.
1512
1513 finline-functions
1514 Common Report Var(flag_inline_functions) Optimization
1515 Integrate functions not declared \"inline\" into their callers when profitable.
1516
1517 finline-functions-called-once
1518 Common Report Var(flag_inline_functions_called_once) Optimization
1519 Integrate functions only required by their single caller.
1520
1521 finline-limit-
1522 Common RejectNegative Joined Alias(finline-limit=)
1523
1524 finline-limit=
1525 Common RejectNegative Joined UInteger
1526 -finline-limit=<number> Limit the size of inlined functions to <number>.
1527
1528 finline-atomics
1529 Common Report Var(flag_inline_atomics) Init(1) Optimization
1530 Inline __atomic operations when a lock free instruction sequence is available.
1531
1532 finstrument-functions
1533 Common Report Var(flag_instrument_function_entry_exit)
1534 Instrument function entry and exit with profiling calls.
1535
1536 finstrument-functions-exclude-function-list=
1537 Common RejectNegative Joined
1538 -finstrument-functions-exclude-function-list=name,...  Do not instrument listed functions.
1539
1540 finstrument-functions-exclude-file-list=
1541 Common RejectNegative Joined
1542 -finstrument-functions-exclude-file-list=filename,...  Do not instrument functions listed in files.
1543
1544 fipa-cp
1545 Common Report Var(flag_ipa_cp) Optimization
1546 Perform interprocedural constant propagation.
1547
1548 fipa-cp-clone
1549 Common Report Var(flag_ipa_cp_clone) Optimization
1550 Perform cloning to make Interprocedural constant propagation stronger.
1551
1552 fipa-cp-alignment
1553 Common Report Var(flag_ipa_cp_alignment) Optimization
1554 Perform alignment discovery and propagation to make Interprocedural constant propagation stronger.
1555
1556 fipa-profile
1557 Common Report Var(flag_ipa_profile) Init(0) Optimization
1558 Perform interprocedural profile propagation.
1559
1560 fipa-pta
1561 Common Report Var(flag_ipa_pta) Init(0) Optimization
1562 Perform interprocedural points-to analysis.
1563
1564 fipa-pure-const
1565 Common Report Var(flag_ipa_pure_const) Init(0) Optimization
1566 Discover pure and const functions.
1567
1568 fipa-icf
1569 Common Report Var(flag_ipa_icf) Optimization
1570 Perform Identical Code Folding for functions and read-only variables.
1571
1572 fipa-icf-functions
1573 Common Report Var(flag_ipa_icf_functions) Optimization
1574 Perform Identical Code Folding for functions.
1575
1576 fipa-icf-variables
1577 Common Report Var(flag_ipa_icf_variables)
1578 Perform Identical Code Folding for variables.
1579
1580 fipa-reference
1581 Common Report Var(flag_ipa_reference) Init(0) Optimization
1582 Discover readonly and non addressable static variables.
1583
1584 fipa-matrix-reorg
1585 Common Ignore
1586 Does nothing. Preserved for backward compatibility.
1587
1588 fipa-struct-reorg
1589 Common Ignore
1590 Does nothing. Preserved for backward compatibility.
1591
1592 fira-algorithm=
1593 Common Joined RejectNegative Enum(ira_algorithm) Var(flag_ira_algorithm) Init(IRA_ALGORITHM_CB) Optimization
1594 -fira-algorithm=[CB|priority] Set the used IRA algorithm.
1595
1596 Enum
1597 Name(ira_algorithm) Type(enum ira_algorithm) UnknownError(unknown IRA algorithm %qs)
1598
1599 EnumValue
1600 Enum(ira_algorithm) String(CB) Value(IRA_ALGORITHM_CB)
1601
1602 EnumValue
1603 Enum(ira_algorithm) String(priority) Value(IRA_ALGORITHM_PRIORITY)
1604
1605 fira-region=
1606 Common Joined RejectNegative Enum(ira_region) Var(flag_ira_region) Init(IRA_REGION_AUTODETECT) Optimization
1607 -fira-region=[one|all|mixed] Set regions for IRA.
1608
1609 Enum
1610 Name(ira_region) Type(enum ira_region) UnknownError(unknown IRA region %qs)
1611
1612 EnumValue
1613 Enum(ira_region) String(one) Value(IRA_REGION_ONE)
1614
1615 EnumValue
1616 Enum(ira_region) String(all) Value(IRA_REGION_ALL)
1617
1618 EnumValue
1619 Enum(ira_region) String(mixed) Value(IRA_REGION_MIXED)
1620
1621 fira-hoist-pressure
1622 Common Report Var(flag_ira_hoist_pressure) Init(1) Optimization
1623 Use IRA based register pressure calculation
1624 in RTL hoist optimizations.
1625
1626 fira-loop-pressure
1627 Common Report Var(flag_ira_loop_pressure) Optimization
1628 Use IRA based register pressure calculation
1629 in RTL loop optimizations.
1630
1631 fira-share-save-slots
1632 Common Report Var(flag_ira_share_save_slots) Init(1) Optimization
1633 Share slots for saving different hard registers.
1634
1635 fira-share-spill-slots
1636 Common Report Var(flag_ira_share_spill_slots) Init(1) Optimization
1637 Share stack slots for spilled pseudo-registers.
1638
1639 fira-verbose=
1640 Common RejectNegative Joined UInteger Var(flag_ira_verbose) Init(5)
1641 -fira-verbose=<number>  Control IRA's level of diagnostic messages.
1642
1643 fivopts
1644 Common Report Var(flag_ivopts) Init(1) Optimization
1645 Optimize induction variables on trees.
1646
1647 fjump-tables
1648 Common Var(flag_jump_tables) Init(1) Optimization
1649 Use jump tables for sufficiently large switch statements.
1650
1651 fkeep-inline-functions
1652 Common Report Var(flag_keep_inline_functions)
1653 Generate code for functions even if they are fully inlined.
1654
1655 fkeep-static-functions
1656 Common Report Var(flag_keep_static_functions)
1657 Generate code for static functions even if they are never called.
1658
1659 fkeep-static-consts
1660 Common Report Var(flag_keep_static_consts) Init(1)
1661 Emit static const variables even if they are not used.
1662
1663 fleading-underscore
1664 Common Report Var(flag_leading_underscore) Init(-1)
1665 Give external symbols a leading underscore.
1666
1667 floop-optimize
1668 Common Ignore
1669 Does nothing.  Preserved for backward compatibility.
1670
1671 flra-remat
1672 Common Report Var(flag_lra_remat) Optimization
1673 Do CFG-sensitive rematerialization in LRA.
1674
1675 flto
1676 Common
1677 Enable link-time optimization.
1678
1679 flto=
1680 Common RejectNegative Joined Var(flag_lto)
1681 Link-time optimization with number of parallel jobs or jobserver.
1682
1683 Enum
1684 Name(lto_partition_model) Type(enum lto_partition_model) UnknownError(unknown LTO partitioning model %qs)
1685
1686 EnumValue
1687 Enum(lto_partition_model) String(none) Value(LTO_PARTITION_NONE)
1688
1689 EnumValue
1690 Enum(lto_partition_model) String(one) Value(LTO_PARTITION_ONE)
1691
1692 EnumValue
1693 Enum(lto_partition_model) String(balanced) Value(LTO_PARTITION_BALANCED)
1694
1695 EnumValue
1696 Enum(lto_partition_model) String(1to1) Value(LTO_PARTITION_1TO1)
1697
1698 EnumValue
1699 Enum(lto_partition_model) String(max) Value(LTO_PARTITION_MAX)
1700
1701 flto-partition=
1702 Common Joined RejectNegative Enum(lto_partition_model) Var(flag_lto_partition) Init(LTO_PARTITION_BALANCED)
1703 Specify the algorithm to partition symbols and vars at linktime.
1704
1705 ; The initial value of -1 comes from Z_DEFAULT_COMPRESSION in zlib.h.
1706 flto-compression-level=
1707 Common Joined RejectNegative UInteger Var(flag_lto_compression_level) Init(-1)
1708 -flto-compression-level=<number>        Use zlib compression level <number> for IL.
1709
1710 flto-odr-type-merging
1711 Common Report Var(flag_lto_odr_type_mering) Init(1)
1712 Merge C++ types using One Definition Rule.
1713
1714 flto-report
1715 Common Report Var(flag_lto_report) Init(0)
1716 Report various link-time optimization statistics.
1717
1718 flto-report-wpa
1719 Common Report Var(flag_lto_report_wpa) Init(0)
1720 Report various link-time optimization statistics for WPA only.
1721
1722 fmath-errno
1723 Common Report Var(flag_errno_math) Init(1) Optimization SetByCombined
1724 Set errno after built-in math functions.
1725
1726 fmax-errors=
1727 Common Joined RejectNegative UInteger Var(flag_max_errors)
1728 -fmax-errors=<number>   Maximum number of errors to report.
1729
1730 fmem-report
1731 Common Report Var(mem_report)
1732 Report on permanent memory allocation.
1733
1734 fmem-report-wpa
1735 Common Report Var(mem_report_wpa)
1736 Report on permanent memory allocation in WPA only.
1737
1738 ; This will attempt to merge constant section constants, if 1 only
1739 ; string constants and constants from constant pool, if 2 also constant
1740 ; variables.
1741 fmerge-all-constants
1742 Common Report Var(flag_merge_constants,2) Init(1)
1743 Attempt to merge identical constants and constant variables.
1744
1745 fmerge-constants
1746 Common Report Var(flag_merge_constants,1)
1747 Attempt to merge identical constants across compilation units.
1748
1749 fmerge-debug-strings
1750 Common Report Var(flag_merge_debug_strings) Init(1)
1751 Attempt to merge identical debug strings across compilation units.
1752
1753 fmessage-length=
1754 Common RejectNegative Joined UInteger
1755 -fmessage-length=<number>       Limit diagnostics to <number> characters per line.  0 suppresses line-wrapping.
1756
1757 fmodulo-sched
1758 Common Report Var(flag_modulo_sched) Optimization
1759 Perform SMS based modulo scheduling before the first scheduling pass.
1760
1761 fmodulo-sched-allow-regmoves
1762 Common Report Var(flag_modulo_sched_allow_regmoves) Optimization
1763 Perform SMS based modulo scheduling with register moves allowed.
1764
1765 fmove-loop-invariants
1766 Common Report Var(flag_move_loop_invariants) Optimization
1767 Move loop invariant computations out of loops.
1768
1769 fdce
1770 Common Var(flag_dce) Init(1) Optimization
1771 Use the RTL dead code elimination pass.
1772
1773 fdse
1774 Common Var(flag_dse) Init(1) Optimization
1775 Use the RTL dead store elimination pass.
1776
1777 freschedule-modulo-scheduled-loops
1778 Common Report Var(flag_resched_modulo_sched) Optimization
1779 Enable/Disable the traditional scheduling in loops that already passed modulo scheduling.
1780
1781 fnon-call-exceptions
1782 Common Report Var(flag_non_call_exceptions) Optimization
1783 Support synchronous non-call exceptions.
1784
1785 foffload=
1786 Common Driver Joined MissingArgError(options or targets missing after %qs)
1787 -foffload=<targets>=<options>  Specify offloading targets and options for them.
1788
1789 foffload-abi=
1790 Common Joined RejectNegative Enum(offload_abi) Var(flag_offload_abi) Init(OFFLOAD_ABI_UNSET)
1791 -foffload-abi=[lp64|ilp32]     Set the ABI to use in an offload compiler.
1792
1793 Enum
1794 Name(offload_abi) Type(enum offload_abi) UnknownError(unknown offload ABI %qs)
1795
1796 EnumValue
1797 Enum(offload_abi) String(ilp32) Value(OFFLOAD_ABI_ILP32)
1798
1799 EnumValue
1800 Enum(offload_abi) String(lp64) Value(OFFLOAD_ABI_LP64)
1801
1802 fomit-frame-pointer
1803 Common Report Var(flag_omit_frame_pointer) Optimization
1804 When possible do not generate stack frames.
1805
1806 fopt-info
1807 Common Report Var(flag_opt_info) Optimization
1808 Enable all optimization info dumps on stderr.
1809
1810 fopt-info-
1811 Common Joined RejectNegative Var(common_deferred_options) Defer
1812 -fopt-info[-<type>=filename]    Dump compiler optimization details.
1813
1814 foptimize-register-move
1815 Common Ignore
1816 Does nothing. Preserved for backward compatibility.
1817
1818 foptimize-sibling-calls
1819 Common Report Var(flag_optimize_sibling_calls) Optimization
1820 Optimize sibling and tail recursive calls.
1821
1822 fpartial-inlining
1823 Common Report Var(flag_partial_inlining) Optimization
1824 Perform partial inlining.
1825
1826 fpre-ipa-mem-report
1827 Common Report Var(pre_ipa_mem_report)
1828 Report on memory allocation before interprocedural optimization.
1829
1830 fpost-ipa-mem-report
1831 Common Report Var(post_ipa_mem_report)
1832 Report on memory allocation before interprocedural optimization.
1833
1834 fpack-struct
1835 Common Report Var(flag_pack_struct) Optimization
1836 Pack structure members together without holes.
1837
1838 fpack-struct=
1839 Common RejectNegative Joined UInteger Optimization
1840 -fpack-struct=<number>  Set initial maximum structure member alignment.
1841
1842 fpcc-struct-return
1843 Common Report Var(flag_pcc_struct_return,1) Init(DEFAULT_PCC_STRUCT_RETURN)
1844 Return small aggregates in memory, not registers.
1845
1846 fpeel-loops
1847 Common Report Var(flag_peel_loops) Optimization
1848 Perform loop peeling.
1849
1850 fpeephole
1851 Common Report Var(flag_no_peephole,0) Optimization
1852 Enable machine specific peephole optimizations.
1853
1854 fpeephole2
1855 Common Report Var(flag_peephole2) Optimization
1856 Enable an RTL peephole pass before sched2.
1857
1858 fPIC
1859 Common Report Var(flag_pic,2) Negative(fPIE) Init(-1)
1860 Generate position-independent code if possible (large mode).
1861
1862 fPIE
1863 Common Report Var(flag_pie,2) Negative(fpic) Init(-1)
1864 Generate position-independent code for executables if possible (large mode).
1865
1866 fpic
1867 Common Report Var(flag_pic,1) Negative(fpie) Init(-1)
1868 Generate position-independent code if possible (small mode).
1869
1870 fpie
1871 Common Report Var(flag_pie,1) Negative(fPIC) Init(-1)
1872 Generate position-independent code for executables if possible (small mode).
1873
1874 fplt
1875 Common Report Var(flag_plt) Init(1) Optimization
1876 Use PLT for PIC calls (-fno-plt: load the address from GOT at call site).
1877
1878 fplugin=
1879 Common Joined RejectNegative Var(common_deferred_options) Defer
1880 Specify a plugin to load.
1881
1882 fplugin-arg-
1883 Common Joined RejectNegative Var(common_deferred_options) Defer
1884 -fplugin-arg-<name>-<key>[=<value>]     Specify argument <key>=<value> for plugin <name>.
1885
1886 fpredictive-commoning
1887 Common Report Var(flag_predictive_commoning) Optimization
1888 Run predictive commoning optimization.
1889
1890 fprefetch-loop-arrays
1891 Common Report Var(flag_prefetch_loop_arrays) Init(-1) Optimization
1892 Generate prefetch instructions, if available, for arrays in loops.
1893
1894 fprofile
1895 Common Report Var(profile_flag)
1896 Enable basic program profiling code.
1897
1898 fprofile-arcs
1899 Common Report Var(profile_arc_flag)
1900 Insert arc-based program profiling code.
1901
1902 fprofile-dir=
1903 Common Joined RejectNegative Var(profile_data_prefix)
1904 Set the top-level directory for storing the profile data.
1905 The default is 'pwd'.
1906
1907 fprofile-correction
1908 Common Report Var(flag_profile_correction)
1909 Enable correction of flow inconsistent profile data input.
1910
1911 fprofile-generate
1912 Common
1913 Enable common options for generating profile info for profile feedback directed optimizations.
1914
1915 fprofile-generate=
1916 Common Joined RejectNegative
1917 Enable common options for generating profile info for profile feedback directed optimizations, and set -fprofile-dir=.
1918
1919 fprofile-use
1920 Common Var(flag_profile_use)
1921 Enable common options for performing profile feedback directed optimizations.
1922
1923 fprofile-use=
1924 Common Joined RejectNegative
1925 Enable common options for performing profile feedback directed optimizations, and set -fprofile-dir=.
1926
1927 fprofile-values
1928 Common Report Var(flag_profile_values)
1929 Insert code to profile values of expressions.
1930
1931 fprofile-report
1932 Common Report Var(profile_report)
1933 Report on consistency of profile.
1934
1935 fprofile-reorder-functions
1936 Common Report Var(flag_profile_reorder_functions)
1937 Enable function reordering that improves code placement.
1938
1939 frandom-seed
1940 Common Var(common_deferred_options) Defer
1941
1942 frandom-seed=
1943 Common Joined RejectNegative Var(common_deferred_options) Defer
1944 -frandom-seed=<string>  Make compile reproducible using <string>.
1945
1946 ; This switch causes the command line that was used to create an
1947 ; object file to be recorded into the object file.  The exact format
1948 ; of this recording is target and binary file format dependent.
1949 ; It is related to the -fverbose-asm switch, but that switch only
1950 ; records information in the assembler output file as comments, so
1951 ; they never reach the object file.
1952 frecord-gcc-switches
1953 Common Report Var(flag_record_gcc_switches)
1954 Record gcc command line switches in the object file.
1955
1956 freg-struct-return
1957 Common Report Var(flag_pcc_struct_return,0) Optimization
1958 Return small aggregates in registers.
1959
1960 fregmove
1961 Common Ignore
1962 Does nothing. Preserved for backward compatibility.
1963
1964 flifetime-dse
1965 Common Report Var(flag_lifetime_dse,2) Init(2) Optimization
1966 Tell DSE that the storage for a C++ object is dead when the constructor
1967 starts and when the destructor finishes.
1968
1969 flifetime-dse=
1970 Common Joined RejectNegative UInteger Var(flag_lifetime_dse) Optimization
1971
1972 flive-range-shrinkage
1973 Common Report Var(flag_live_range_shrinkage) Init(0) Optimization
1974 Relief of register pressure through live range shrinkage.
1975
1976 frename-registers
1977 Common Report Var(flag_rename_registers) Init(2) Optimization
1978 Perform a register renaming optimization pass.
1979
1980 fschedule-fusion
1981 Common Report Var(flag_schedule_fusion) Init(2) Optimization
1982 Perform a target dependent instruction fusion optimization pass.
1983
1984 freorder-blocks
1985 Common Report Var(flag_reorder_blocks) Optimization
1986 Reorder basic blocks to improve code placement.
1987
1988 freorder-blocks-algorithm=
1989 Common Joined RejectNegative Enum(reorder_blocks_algorithm) Var(flag_reorder_blocks_algorithm) Init(REORDER_BLOCKS_ALGORITHM_SIMPLE) Optimization
1990 -freorder-blocks-algorithm=[simple|stc] Set the used basic block reordering algorithm.
1991
1992 Enum
1993 Name(reorder_blocks_algorithm) Type(enum reorder_blocks_algorithm) UnknownError(unknown basic block reordering algorithm %qs)
1994
1995 EnumValue
1996 Enum(reorder_blocks_algorithm) String(simple) Value(REORDER_BLOCKS_ALGORITHM_SIMPLE)
1997
1998 EnumValue
1999 Enum(reorder_blocks_algorithm) String(stc) Value(REORDER_BLOCKS_ALGORITHM_STC)
2000
2001 freorder-blocks-and-partition
2002 Common Report Var(flag_reorder_blocks_and_partition) Optimization
2003 Reorder basic blocks and partition into hot and cold sections.
2004
2005 freorder-functions
2006 Common Report Var(flag_reorder_functions) Optimization
2007 Reorder functions to improve code placement.
2008
2009 frerun-cse-after-loop
2010 Common Report Var(flag_rerun_cse_after_loop) Optimization
2011 Add a common subexpression elimination pass after loop optimizations.
2012
2013 frerun-loop-opt
2014 Common Ignore
2015 Does nothing.  Preserved for backward compatibility.
2016
2017 frounding-math
2018 Common Report Var(flag_rounding_math) Optimization SetByCombined
2019 Disable optimizations that assume default FP rounding behavior.
2020
2021 fsched-interblock
2022 Common Report Var(flag_schedule_interblock) Init(1) Optimization
2023 Enable scheduling across basic blocks.
2024
2025 fsched-pressure
2026 Common Report Var(flag_sched_pressure) Init(0) Optimization
2027 Enable register pressure sensitive insn scheduling.
2028
2029 fsched-spec
2030 Common Report Var(flag_schedule_speculative) Init(1) Optimization
2031 Allow speculative motion of non-loads.
2032
2033 fsched-spec-load
2034 Common Report Var(flag_schedule_speculative_load) Optimization
2035 Allow speculative motion of some loads.
2036
2037 fsched-spec-load-dangerous
2038 Common Report Var(flag_schedule_speculative_load_dangerous) Optimization
2039 Allow speculative motion of more loads.
2040
2041 fsched-verbose=
2042 Common RejectNegative Joined UInteger Var(sched_verbose_param) Init(1)
2043 -fsched-verbose=<number>        Set the verbosity level of the scheduler.
2044
2045 fsched2-use-superblocks
2046 Common Report Var(flag_sched2_use_superblocks) Optimization
2047 If scheduling post reload, do superblock scheduling.
2048
2049 fsched2-use-traces
2050 Common Ignore
2051 Does nothing.  Preserved for backward compatibility.
2052
2053 fschedule-insns
2054 Common Report Var(flag_schedule_insns) Optimization
2055 Reschedule instructions before register allocation.
2056
2057 fschedule-insns2
2058 Common Report Var(flag_schedule_insns_after_reload) Optimization
2059 Reschedule instructions after register allocation.
2060
2061 ; This flag should be on when a target implements non-trivial
2062 ; scheduling hooks, maybe saving some information for its own sake.
2063 ; On IA64, for example, this is used for correct bundling.
2064 fselective-scheduling
2065 Common Report Var(flag_selective_scheduling) Optimization
2066 Schedule instructions using selective scheduling algorithm.
2067
2068 fselective-scheduling2
2069 Common Report Var(flag_selective_scheduling2) Optimization
2070 Run selective scheduling after reload.
2071
2072 fsel-sched-pipelining
2073 Common Report Var(flag_sel_sched_pipelining) Init(0) Optimization
2074 Perform software pipelining of inner loops during selective scheduling.
2075
2076 fsel-sched-pipelining-outer-loops
2077 Common Report Var(flag_sel_sched_pipelining_outer_loops) Init(0) Optimization
2078 Perform software pipelining of outer loops during selective scheduling.
2079
2080 fsel-sched-reschedule-pipelined
2081 Common Report Var(flag_sel_sched_reschedule_pipelined) Init(0) Optimization
2082 Reschedule pipelined regions without pipelining.
2083
2084 fsemantic-interposition
2085 Common Report Var(flag_semantic_interposition) Init(1)
2086 Allow interposing function (or variables) by ones with different semantics (or initializer) respectively by dynamic linker.
2087
2088 ; sched_stalled_insns means that insns can be moved prematurely from the queue
2089 ; of stalled insns into the ready list.
2090 fsched-stalled-insns
2091 Common Report Var(flag_sched_stalled_insns) Optimization UInteger
2092 Allow premature scheduling of queued insns.
2093
2094 fsched-stalled-insns=
2095 Common RejectNegative Joined UInteger Optimization
2096 -fsched-stalled-insns=<number>  Set number of queued insns that can be prematurely scheduled.
2097
2098 ; sched_stalled_insns_dep controls how many recently scheduled cycles will
2099 ; be examined for a dependency on a stalled insn that is candidate for
2100 ; premature removal from the queue of stalled insns into the ready list (has
2101 ; an effect only if the flag 'sched_stalled_insns' is set).
2102 fsched-stalled-insns-dep
2103 Common Report Var(flag_sched_stalled_insns_dep,1) Init(1) Optimization UInteger
2104 Set dependence distance checking in premature scheduling of queued insns.
2105
2106 fsched-stalled-insns-dep=
2107 Common RejectNegative Joined UInteger Optimization
2108 -fsched-stalled-insns-dep=<number>      Set dependence distance checking in premature scheduling of queued insns.
2109
2110 fsched-group-heuristic
2111 Common Report Var(flag_sched_group_heuristic) Init(1) Optimization
2112 Enable the group heuristic in the scheduler.
2113
2114 fsched-critical-path-heuristic
2115 Common Report Var(flag_sched_critical_path_heuristic) Init(1) Optimization
2116 Enable the critical path heuristic in the scheduler.
2117
2118 fsched-spec-insn-heuristic
2119 Common Report Var(flag_sched_spec_insn_heuristic) Init(1) Optimization
2120 Enable the speculative instruction heuristic in the scheduler.
2121
2122 fsched-rank-heuristic
2123 Common Report Var(flag_sched_rank_heuristic) Init(1) Optimization
2124 Enable the rank heuristic in the scheduler.
2125
2126 fsched-last-insn-heuristic
2127 Common Report Var(flag_sched_last_insn_heuristic) Init(1) Optimization
2128 Enable the last instruction heuristic in the scheduler.
2129
2130 fsched-dep-count-heuristic
2131 Common Report Var(flag_sched_dep_count_heuristic) Init(1) Optimization
2132 Enable the dependent count heuristic in the scheduler.
2133
2134 fsection-anchors
2135 Common Report Var(flag_section_anchors) Optimization
2136 Access data in the same section from shared anchor points.
2137
2138 fsee
2139 Common Ignore
2140 Does nothing.  Preserved for backward compatibility.
2141
2142 fzee
2143 Common Ignore
2144 Does nothing.  Preserved for backward compatibility.
2145
2146 free
2147 Common Report Var(flag_ree) Init(0)
2148 Turn on Redundant Extensions Elimination pass.
2149
2150 fshow-column
2151 Common Report Var(flag_show_column) Init(1)
2152 Show column numbers in diagnostics, when available.  Default on.
2153
2154 fshrink-wrap
2155 Common Report Var(flag_shrink_wrap) Optimization
2156 Emit function prologues only before parts of the function that need it,
2157 rather than at the top of the function.
2158
2159 fsignaling-nans
2160 Common Report Var(flag_signaling_nans) Optimization SetByCombined
2161 Disable optimizations observable by IEEE signaling NaNs.
2162
2163 fsigned-zeros
2164 Common Report Var(flag_signed_zeros) Init(1) Optimization SetByCombined
2165 Disable floating point optimizations that ignore the IEEE signedness of zero.
2166
2167 fsingle-precision-constant
2168 Common Report Var(flag_single_precision_constant) Optimization
2169 Convert floating point constants to single precision constants.
2170
2171 fsplit-ivs-in-unroller
2172 Common Report Var(flag_split_ivs_in_unroller) Init(1) Optimization
2173 Split lifetimes of induction variables when loops are unrolled.
2174
2175 fsplit-stack
2176 Common Report Var(flag_split_stack) Init(-1)
2177 Generate discontiguous stack frames.
2178
2179 fsplit-wide-types
2180 Common Report Var(flag_split_wide_types) Optimization
2181 Split wide types into independent registers.
2182
2183 fssa-backprop
2184 Common Report Var(flag_ssa_backprop) Init(1) Optimization
2185 Enable backward propagation of use properties at the SSA level.
2186
2187 fssa-phiopt
2188 Common Report Var(flag_ssa_phiopt) Optimization
2189 Optimize conditional patterns using SSA PHI nodes.
2190
2191 fstdarg-opt
2192 Common Report Var(flag_stdarg_opt) Init(1) Optimization
2193 Optimize amount of stdarg registers saved to stack at start of function.
2194
2195 fvariable-expansion-in-unroller
2196 Common Report Var(flag_variable_expansion_in_unroller) Optimization
2197 Apply variable expansion when loops are unrolled.
2198
2199 fstack-check=
2200 Common Report RejectNegative Joined
2201 -fstack-check=[no|generic|specific]     Insert stack checking code into the program.
2202
2203 fstack-check
2204 Common Alias(fstack-check=, specific, no)
2205 Insert stack checking code into the program.  Same as -fstack-check=specific.
2206
2207 fstack-limit
2208 Common Var(common_deferred_options) Defer
2209
2210 fstack-limit-register=
2211 Common RejectNegative Joined Var(common_deferred_options) Defer
2212 -fstack-limit-register=<register>       Trap if the stack goes past <register>.
2213
2214 fstack-limit-symbol=
2215 Common RejectNegative Joined Var(common_deferred_options) Defer
2216 -fstack-limit-symbol=<name>     Trap if the stack goes past symbol <name>.
2217
2218 fstack-protector
2219 Common Report Var(flag_stack_protect, 1) Init(-1)
2220 Use propolice as a stack protection method.
2221
2222 fstack-protector-all
2223 Common Report RejectNegative Var(flag_stack_protect, 2) Init(-1)
2224 Use a stack protection method for every function.
2225
2226 fstack-protector-strong
2227 Common Report RejectNegative Var(flag_stack_protect, 3) Init(-1)
2228 Use a smart stack protection method for certain functions.
2229
2230 fstack-protector-explicit
2231 Common Report RejectNegative Var(flag_stack_protect, 4)
2232 Use stack protection method only for functions with the stack_protect attribute.
2233
2234 fstack-usage
2235 Common RejectNegative Var(flag_stack_usage)
2236 Output stack usage information on a per-function basis.
2237
2238 fstrength-reduce
2239 Common Ignore
2240 Does nothing.  Preserved for backward compatibility.
2241
2242 ; Nonzero if we should do (language-dependent) alias analysis.
2243 ; Typically, this analysis will assume that expressions of certain
2244 ; types do not alias expressions of certain other types.  Only used
2245 ; if alias analysis (in general) is enabled.
2246 fstrict-aliasing
2247 Common Report Var(flag_strict_aliasing) Optimization
2248 Assume strict aliasing rules apply.
2249
2250 fstrict-overflow
2251 Common Report Var(flag_strict_overflow) Optimization
2252 Treat signed overflow as undefined.
2253
2254 fsync-libcalls
2255 Common Report Var(flag_sync_libcalls) Init(1)
2256 Implement __atomic operations via libcalls to legacy __sync functions.
2257
2258 fsyntax-only
2259 Common Report Var(flag_syntax_only)
2260 Check for syntax errors, then stop.
2261
2262 ftest-coverage
2263 Common Report Var(flag_test_coverage)
2264 Create data files needed by \"gcov\".
2265
2266 fthread-jumps
2267 Common Report Var(flag_thread_jumps) Optimization
2268 Perform jump threading optimizations.
2269
2270 ftime-report
2271 Common Report Var(time_report)
2272 Report the time taken by each compiler pass.
2273
2274 ftls-model=
2275 Common Joined RejectNegative Enum(tls_model) Var(flag_tls_default) Init(TLS_MODEL_GLOBAL_DYNAMIC)
2276 -ftls-model=[global-dynamic|local-dynamic|initial-exec|local-exec]      Set the default thread-local storage code generation model.
2277
2278 Enum
2279 Name(tls_model) Type(enum tls_model) UnknownError(unknown TLS model %qs)
2280
2281 EnumValue
2282 Enum(tls_model) String(global-dynamic) Value(TLS_MODEL_GLOBAL_DYNAMIC)
2283
2284 EnumValue
2285 Enum(tls_model) String(local-dynamic) Value(TLS_MODEL_LOCAL_DYNAMIC)
2286
2287 EnumValue
2288 Enum(tls_model) String(initial-exec) Value(TLS_MODEL_INITIAL_EXEC)
2289
2290 EnumValue
2291 Enum(tls_model) String(local-exec) Value(TLS_MODEL_LOCAL_EXEC)
2292
2293 ftoplevel-reorder
2294 Common Report Var(flag_toplevel_reorder) Init(2)
2295 Reorder top level functions, variables, and asms.
2296
2297 ftracer
2298 Common Report Var(flag_tracer) Optimization
2299 Perform superblock formation via tail duplication.
2300
2301 ; Zero means that floating-point math operations cannot generate a
2302 ; (user-visible) trap.  This is the case, for example, in nonstop
2303 ; IEEE 754 arithmetic.
2304 ftrapping-math
2305 Common Report Var(flag_trapping_math) Init(1) Optimization SetByCombined
2306 Assume floating-point operations can trap.
2307
2308 ftrapv
2309 Common Report Var(flag_trapv) Optimization
2310 Trap for signed overflow in addition, subtraction and multiplication.
2311
2312 ftree-ccp
2313 Common Report Var(flag_tree_ccp) Optimization
2314 Enable SSA-CCP optimization on trees.
2315
2316 ftree-bit-ccp
2317 Common Report Var(flag_tree_bit_ccp) Optimization
2318 Enable SSA-BIT-CCP optimization on trees.
2319
2320 ftree-store-ccp
2321 Common Ignore
2322 Does nothing.  Preserved for backward compatibility.
2323
2324 ftree-ch
2325 Common Report Var(flag_tree_ch) Optimization
2326 Enable loop header copying on trees.
2327
2328 ftree-coalesce-inlined-vars
2329 Common Ignore RejectNegative
2330 Does nothing.  Preserved for backward compatibility.
2331
2332 ftree-coalesce-vars
2333 Common Report Var(flag_tree_coalesce_vars) Optimization
2334 Enable SSA coalescing of user variables.
2335
2336 ftree-copyrename
2337 Common Ignore
2338 Does nothing.  Preserved for backward compatibility.
2339
2340 ftree-copy-prop
2341 Common Report Var(flag_tree_copy_prop) Optimization
2342 Enable copy propagation on trees.
2343
2344 ftree-store-copy-prop
2345 Common Ignore
2346 Does nothing.  Preserved for backward compatibility.
2347
2348 ftree-cselim
2349 Common Report Var(flag_tree_cselim) Init(2) Optimization
2350 Transform condition stores into unconditional ones.
2351
2352 ftree-switch-conversion
2353 Common Report Var(flag_tree_switch_conversion) Optimization
2354 Perform conversions of switch initializations.
2355
2356 ftree-dce
2357 Common Report Var(flag_tree_dce) Optimization
2358 Enable SSA dead code elimination optimization on trees.
2359
2360 ftree-dominator-opts
2361 Common Report Var(flag_tree_dom) Optimization
2362 Enable dominator optimizations.
2363
2364 ftree-tail-merge
2365 Common Report Var(flag_tree_tail_merge) Optimization
2366 Enable tail merging on trees.
2367
2368 ftree-dse
2369 Common Report Var(flag_tree_dse) Optimization
2370 Enable dead store elimination.
2371
2372 ftree-forwprop
2373 Common Report Var(flag_tree_forwprop) Init(1) Optimization
2374 Enable forward propagation on trees.
2375
2376 ftree-fre
2377 Common Report Var(flag_tree_fre) Optimization
2378 Enable Full Redundancy Elimination (FRE) on trees.
2379
2380 foptimize-strlen
2381 Common Report Var(flag_optimize_strlen) Optimization
2382 Enable string length optimizations on trees.
2383
2384 fisolate-erroneous-paths-dereference
2385 Common Report Var(flag_isolate_erroneous_paths_dereference) Optimization
2386 Detect paths that trigger erroneous or undefined behavior due to
2387 dereferencing a null pointer.  Isolate those paths from the main control
2388 flow and turn the statement with erroneous or undefined behavior into a trap.
2389
2390 fisolate-erroneous-paths-attribute
2391 Common Report Var(flag_isolate_erroneous_paths_attribute) Optimization
2392 Detect paths that trigger erroneous or undefined behavior due a null value
2393 being used in a way forbidden by a returns_nonnull or nonnull
2394 attribute.  Isolate those paths from the main control flow and turn the
2395 statement with erroneous or undefined behavior into a trap.
2396
2397 ftree-loop-distribution
2398 Common Report Var(flag_tree_loop_distribution) Optimization
2399 Enable loop distribution on trees.
2400
2401 ftree-loop-distribute-patterns
2402 Common Report Var(flag_tree_loop_distribute_patterns) Optimization
2403 Enable loop distribution for patterns transformed into a library call.
2404
2405 ftree-loop-im
2406 Common Report Var(flag_tree_loop_im) Init(1) Optimization
2407 Enable loop invariant motion on trees.
2408
2409 ftree-loop-linear
2410 Common Alias(floop-nest-optimize)
2411 Enable loop nest transforms.  Same as -floop-nest-optimize.
2412
2413 ftree-loop-ivcanon
2414 Common Report Var(flag_tree_loop_ivcanon) Init(1) Optimization
2415 Create canonical induction variables in loops.
2416
2417 ftree-loop-optimize
2418 Common Report Var(flag_tree_loop_optimize) Init(1) Optimization
2419 Enable loop optimizations on tree level.
2420
2421 ftree-parallelize-loops=
2422 Common Report Joined RejectNegative UInteger Var(flag_tree_parallelize_loops) Init(1) Optimization
2423 Enable automatic parallelization of loops.
2424
2425 ftree-phiprop
2426 Common Report Var(flag_tree_phiprop) Init(1) Optimization
2427 Enable hoisting loads from conditional pointers.
2428
2429 ftree-pre
2430 Common Report Var(flag_tree_pre) Optimization
2431 Enable SSA-PRE optimization on trees.
2432
2433 ftree-partial-pre
2434 Common Report Var(flag_tree_partial_pre) Optimization
2435 In SSA-PRE optimization on trees, enable partial-partial redundancy elimination.
2436
2437 ftree-pta
2438 Common Report Var(flag_tree_pta) Optimization
2439 Perform function-local points-to analysis on trees.
2440
2441 ftree-reassoc
2442 Common Report Var(flag_tree_reassoc) Init(1) Optimization
2443 Enable reassociation on tree level.
2444
2445 ftree-salias
2446 Common Ignore
2447 Does nothing.  Preserved for backward compatibility.
2448
2449 ftree-sink
2450 Common Report Var(flag_tree_sink) Optimization
2451 Enable SSA code sinking on trees.
2452
2453 ftree-slsr
2454 Common Report Var(flag_tree_slsr) Optimization
2455 Perform straight-line strength reduction.
2456
2457 ftree-sra
2458 Common Report Var(flag_tree_sra) Optimization
2459 Perform scalar replacement of aggregates.
2460
2461 ftree-ter
2462 Common Report Var(flag_tree_ter) Optimization
2463 Replace temporary expressions in the SSA->normal pass.
2464
2465 ftree-lrs
2466 Common Report Var(flag_tree_live_range_split) Optimization
2467 Perform live range splitting during the SSA->normal pass.
2468
2469 ftree-vrp
2470 Common Report Var(flag_tree_vrp) Init(0) Optimization
2471 Perform Value Range Propagation on trees.
2472
2473 fsplit-paths
2474 Common Report Var(flag_split_paths) Init(0) Optimization
2475 Split paths leading to loop backedges.
2476
2477 funconstrained-commons
2478 Common Var(flag_unconstrained_commons) Optimization
2479 Assume common declarations may be overridden with ones with a larger
2480 trailing array.
2481
2482 funit-at-a-time
2483 Common Report Var(flag_unit_at_a_time) Init(1)
2484 Compile whole compilation unit at a time.
2485
2486 funroll-loops
2487 Common Report Var(flag_unroll_loops) Optimization
2488 Perform loop unrolling when iteration count is known.
2489
2490 funroll-all-loops
2491 Common Report Var(flag_unroll_all_loops) Optimization
2492 Perform loop unrolling for all loops.
2493
2494 ; Nonzero means that loop optimizer may assume that the induction variables
2495 ; that control loops do not overflow and that the loops with nontrivial
2496 ; exit condition are not infinite
2497 funsafe-loop-optimizations
2498 Common Report Var(flag_unsafe_loop_optimizations) Optimization
2499 Allow loop optimizations to assume that the loops behave in normal way.
2500
2501 fassociative-math
2502 Common Report Var(flag_associative_math) SetByCombined Optimization
2503 Allow optimization for floating-point arithmetic which may change the
2504 result of the operation due to rounding.
2505
2506 freciprocal-math
2507 Common Report Var(flag_reciprocal_math) SetByCombined Optimization
2508 Same as -fassociative-math for expressions which include division.
2509
2510 ; Nonzero means that unsafe floating-point math optimizations are allowed
2511 ; for the sake of speed.  IEEE compliance is not guaranteed, and operations
2512 ; are allowed to assume that their arguments and results are "normal"
2513 ; (e.g., nonnegative for SQRT).
2514 funsafe-math-optimizations
2515 Common Report Var(flag_unsafe_math_optimizations) Optimization SetByCombined
2516 Allow math optimizations that may violate IEEE or ISO standards.
2517
2518 funswitch-loops
2519 Common Report Var(flag_unswitch_loops) Optimization
2520 Perform loop unswitching.
2521
2522 funwind-tables
2523 Common Report Var(flag_unwind_tables) Optimization
2524 Just generate unwind tables for exception handling.
2525
2526 fuse-ld=bfd
2527 Common Driver Negative(fuse-ld=gold)
2528 Use the bfd linker instead of the default linker.
2529
2530 fuse-ld=gold
2531 Common Driver Negative(fuse-ld=bfd)
2532 Use the gold linker instead of the default linker.
2533
2534 fuse-linker-plugin
2535 Common Undocumented Var(flag_use_linker_plugin)
2536
2537 ; Positive if we should track variables, negative if we should run
2538 ; the var-tracking pass only to discard debug annotations, zero if
2539 ; we're not to run it.  When flag_var_tracking == 2 (AUTODETECT_VALUE) it
2540 ; will be set according to optimize, debug_info_level and debug_hooks
2541 ; in process_options ().
2542 fvar-tracking
2543 Common Report Var(flag_var_tracking) Init(2) Optimization
2544 Perform variable tracking.
2545
2546 ; Positive if we should track variables at assignments, negative if
2547 ; we should run the var-tracking pass only to discard debug
2548 ; annotations.  When flag_var_tracking_assignments ==
2549 ; AUTODETECT_VALUE it will be set according to flag_var_tracking.
2550 fvar-tracking-assignments
2551 Common Report Var(flag_var_tracking_assignments) Init(2) Optimization
2552 Perform variable tracking by annotating assignments.
2553
2554 ; Nonzero if we should toggle flag_var_tracking_assignments after
2555 ; processing options and computing its default.  */
2556 fvar-tracking-assignments-toggle
2557 Common Report Var(flag_var_tracking_assignments_toggle) Optimization
2558 Toggle -fvar-tracking-assignments.
2559
2560 ; Positive if we should track uninitialized variables, negative if
2561 ; we should run the var-tracking pass only to discard debug
2562 ; annotations.  When flag_var_tracking_uninit == AUTODETECT_VALUE it
2563 ; will be set according to flag_var_tracking.
2564 fvar-tracking-uninit
2565 Common Report Var(flag_var_tracking_uninit) Optimization
2566 Perform variable tracking and also tag variables that are uninitialized.
2567
2568 ftree-vectorize
2569 Common Report Var(flag_tree_vectorize) Optimization
2570 Enable vectorization on trees.
2571
2572 ftree-vectorizer-verbose=
2573 Common Joined RejectNegative Ignore
2574 Does nothing.  Preserved for backward compatibility.
2575
2576 ftree-loop-vectorize
2577 Common Report Var(flag_tree_loop_vectorize) Optimization
2578 Enable loop vectorization on trees.
2579
2580 ftree-slp-vectorize
2581 Common Report Var(flag_tree_slp_vectorize) Optimization
2582 Enable basic block vectorization (SLP) on trees.
2583
2584 fvect-cost-model=
2585 Common Joined RejectNegative Enum(vect_cost_model) Var(flag_vect_cost_model) Init(VECT_COST_MODEL_DEFAULT) Optimization
2586 Specifies the cost model for vectorization.
2587
2588 fsimd-cost-model=
2589 Common Joined RejectNegative Enum(vect_cost_model) Var(flag_simd_cost_model) Init(VECT_COST_MODEL_UNLIMITED) Optimization
2590 Specifies the vectorization cost model for code marked with a simd directive.
2591
2592 Enum
2593 Name(vect_cost_model) Type(enum vect_cost_model) UnknownError(unknown vectorizer cost model %qs)
2594
2595 EnumValue
2596 Enum(vect_cost_model) String(unlimited) Value(VECT_COST_MODEL_UNLIMITED)
2597
2598 EnumValue
2599 Enum(vect_cost_model) String(dynamic) Value(VECT_COST_MODEL_DYNAMIC)
2600
2601 EnumValue
2602 Enum(vect_cost_model) String(cheap) Value(VECT_COST_MODEL_CHEAP)
2603
2604 fvect-cost-model
2605 Common RejectNegative Alias(fvect-cost-model=,dynamic)
2606 Enables the dynamic vectorizer cost model.  Preserved for backward compatibility.
2607
2608 fno-vect-cost-model
2609 Common RejectNegative Alias(fvect-cost-model=,unlimited)
2610 Enables the unlimited vectorizer cost model.  Preserved for backward compatibility.
2611
2612 ftree-vect-loop-version
2613 Common Ignore
2614 Does nothing. Preserved for backward compatibility.
2615
2616 ftree-scev-cprop
2617 Common Report Var(flag_tree_scev_cprop) Init(1) Optimization
2618 Enable copy propagation of scalar-evolution information.
2619
2620 ; -fverbose-asm causes extra commentary information to be produced in
2621 ; the generated assembly code (to make it more readable).  This option
2622 ; is generally only of use to those who actually need to read the
2623 ; generated assembly code (perhaps while debugging the compiler itself).
2624 ; -fno-verbose-asm, the default, causes the extra information
2625 ; to not be added and is useful when comparing two assembler files.
2626 fverbose-asm
2627 Common Report Var(flag_verbose_asm)
2628 Add extra commentary to assembler output.
2629
2630 fvisibility=
2631 Common Joined RejectNegative Enum(symbol_visibility) Var(default_visibility) Init(VISIBILITY_DEFAULT)
2632 -fvisibility=[default|internal|hidden|protected]        Set the default symbol visibility.
2633
2634 Enum
2635 Name(symbol_visibility) Type(enum symbol_visibility) UnknownError(unrecognized visibility value %qs)
2636
2637 EnumValue
2638 Enum(symbol_visibility) String(default) Value(VISIBILITY_DEFAULT)
2639
2640 EnumValue
2641 Enum(symbol_visibility) String(internal) Value(VISIBILITY_INTERNAL)
2642
2643 EnumValue
2644 Enum(symbol_visibility) String(hidden) Value(VISIBILITY_HIDDEN)
2645
2646 EnumValue
2647 Enum(symbol_visibility) String(protected) Value(VISIBILITY_PROTECTED)
2648
2649 fvtable-verify=
2650 Common Joined RejectNegative Enum(vtv_priority) Var(flag_vtable_verify) Init(VTV_NO_PRIORITY)
2651 Validate vtable pointers before using them.
2652
2653 Enum
2654 Name(vtv_priority) Type(enum vtv_priority) UnknownError(unknown vtable verify initialization priority %qs)
2655
2656 EnumValue
2657 Enum(vtv_priority) String(none) Value(VTV_NO_PRIORITY)
2658
2659 EnumValue
2660 Enum(vtv_priority) String(std) Value(VTV_STANDARD_PRIORITY)
2661
2662 EnumValue
2663 Enum(vtv_priority) String(preinit) Value(VTV_PREINIT_PRIORITY)
2664
2665 fvtv-counts
2666 Common Var(flag_vtv_counts)
2667 Output vtable verification counters.
2668
2669 fvtv-debug
2670 Common Var(flag_vtv_debug)
2671 Output vtable verification pointer sets information.
2672
2673 fvpt
2674 Common Report Var(flag_value_profile_transformations) Optimization
2675 Use expression value profiles in optimizations.
2676
2677 fweb
2678 Common Report Var(flag_web) Init(2) Optimization
2679 Construct webs and split unrelated uses of single variable.
2680
2681 ftree-builtin-call-dce
2682 Common Report Var(flag_tree_builtin_call_dce) Init(0) Optimization
2683 Enable conditional dead code elimination for builtin calls.
2684
2685 fwhole-program
2686 Common Report Var(flag_whole_program) Init(0)
2687 Perform whole program optimizations.
2688
2689 fwrapv
2690 Common Report Var(flag_wrapv) Optimization
2691 Assume signed arithmetic overflow wraps around.
2692
2693 fzero-initialized-in-bss
2694 Common Report Var(flag_zero_initialized_in_bss) Init(1)
2695 Put zero initialized data in the bss section.
2696
2697 g
2698 Common JoinedOrMissing
2699 Generate debug information in default format.
2700
2701 gcoff
2702 Common JoinedOrMissing Negative(gdwarf)
2703 Generate debug information in COFF format.
2704
2705 gdwarf
2706 Common JoinedOrMissing Negative(gdwarf-)
2707 Generate debug information in default version of DWARF format.
2708
2709 gdwarf-
2710 Common Joined UInteger Var(dwarf_version) Init(4) Negative(gstabs)
2711 Generate debug information in DWARF v2 (or later) format.
2712
2713 ggdb
2714 Common JoinedOrMissing
2715 Generate debug information in default extended format.
2716
2717 gno-pubnames
2718 Common Negative(gpubnames) Var(debug_generate_pub_sections, 0) Init(-1)
2719 Don't generate DWARF pubnames and pubtypes sections.
2720
2721 gpubnames
2722 Common Negative(ggnu-pubnames) Var(debug_generate_pub_sections, 1)
2723 Generate DWARF pubnames and pubtypes sections.
2724
2725 ggnu-pubnames
2726 Common Negative(gno-pubnames) Var(debug_generate_pub_sections, 2)
2727 Generate DWARF pubnames and pubtypes sections with GNU extensions.
2728
2729 gno-record-gcc-switches
2730 Common RejectNegative Var(dwarf_record_gcc_switches,0) Init(1)
2731 Don't record gcc command line switches in DWARF DW_AT_producer.
2732
2733 grecord-gcc-switches
2734 Common RejectNegative Var(dwarf_record_gcc_switches,1)
2735 Record gcc command line switches in DWARF DW_AT_producer.
2736
2737 gno-split-dwarf
2738 Common Driver RejectNegative Var(dwarf_split_debug_info,0) Init(0)
2739 Don't generate debug information in separate .dwo files.
2740
2741 gsplit-dwarf
2742 Common Driver RejectNegative Var(dwarf_split_debug_info,1)
2743 Generate debug information in separate .dwo files.
2744
2745 gstabs
2746 Common JoinedOrMissing Negative(gstabs+)
2747 Generate debug information in STABS format.
2748
2749 gstabs+
2750 Common JoinedOrMissing Negative(gvms)
2751 Generate debug information in extended STABS format.
2752
2753 gno-strict-dwarf
2754 Common RejectNegative Var(dwarf_strict,0) Init(0)
2755 Emit DWARF additions beyond selected version.
2756
2757 gstrict-dwarf
2758 Common Report RejectNegative Var(dwarf_strict,1)
2759 Don't emit DWARF additions beyond selected version.
2760
2761 gtoggle
2762 Common Report Var(flag_gtoggle)
2763 Toggle debug information generation.
2764
2765 gvms
2766 Common JoinedOrMissing Negative(gxcoff)
2767 Generate debug information in VMS format.
2768
2769 gxcoff
2770 Common JoinedOrMissing Negative(gxcoff+)
2771 Generate debug information in XCOFF format.
2772
2773 gxcoff+
2774 Common JoinedOrMissing Negative(gcoff)
2775 Generate debug information in extended XCOFF format.
2776
2777 Enum
2778 Name(compressed_debug_sections) Type(int)
2779
2780 ; Since -gz= is completely handled in specs, the values aren't used and we
2781 ; assign arbitrary constants.
2782 EnumValue
2783 Enum(compressed_debug_sections) String(none) Value(0)
2784
2785 EnumValue
2786 Enum(compressed_debug_sections) String(zlib) Value(1)
2787
2788 EnumValue
2789 Enum(compressed_debug_sections) String(zlib-gnu) Value(2)
2790
2791 gz
2792 Common Driver
2793 Generate compressed debug sections.
2794
2795 gz=
2796 Common Driver Joined Enum(compressed_debug_sections)
2797 -gz=<format>    Generate compressed debug sections in format <format>.
2798
2799 h
2800 Driver Joined Separate
2801
2802 iplugindir=
2803 Common Joined Var(plugindir_string) Init(0)
2804 -iplugindir=<dir>       Set <dir> to be the default plugin directory.
2805
2806 imultiarch
2807 Common Joined Separate RejectDriver Var(imultiarch) Init(0)
2808 -imultiarch <dir>       Set <dir> to be the multiarch include subdirectory.
2809
2810 l
2811 Driver Joined Separate
2812
2813 n
2814 Driver
2815
2816 no-canonical-prefixes
2817 Driver
2818
2819 nodefaultlibs
2820 Driver
2821
2822 nostartfiles
2823 Driver
2824
2825 nostdlib
2826 Driver
2827
2828 o
2829 Common Driver Joined Separate Var(asm_file_name) MissingArgError(missing filename after %qs)
2830 -o <file>       Place output into <file>.
2831
2832 p
2833 Common Var(profile_flag)
2834 Enable function profiling.
2835
2836 pass-exit-codes
2837 Driver Var(pass_exit_codes)
2838
2839 pedantic
2840 Common Alias(Wpedantic)
2841
2842 pedantic-errors
2843 Common Var(flag_pedantic_errors)
2844 Like -pedantic but issue them as errors.
2845
2846 pg
2847 Driver
2848
2849 pipe
2850 Driver Var(use_pipes)
2851
2852 print-file-name=
2853 Driver JoinedOrMissing Var(print_file_name)
2854
2855 print-libgcc-file-name
2856 Driver
2857
2858 print-multi-directory
2859 Driver Var(print_multi_directory)
2860
2861 print-multi-lib
2862 Driver Var(print_multi_lib)
2863
2864 print-multi-os-directory
2865 Driver Var(print_multi_os_directory)
2866
2867 print-multiarch
2868 Driver Var(print_multiarch)
2869
2870 print-prog-name=
2871 Driver JoinedOrMissing Var(print_prog_name)
2872
2873 print-search-dirs
2874 Driver Var(print_search_dirs)
2875
2876 print-sysroot
2877 Driver Var(print_sysroot)
2878
2879 print-sysroot-headers-suffix
2880 Driver Var(print_sysroot_headers_suffix)
2881
2882 quiet
2883 Common Var(quiet_flag) RejectDriver
2884 Do not display functions compiled or elapsed time.
2885
2886 r
2887 Driver
2888
2889 s
2890 Driver
2891
2892 save-temps
2893 Driver
2894
2895 save-temps=
2896 Driver Joined
2897
2898 t
2899 Driver
2900
2901 time
2902 Driver Var(report_times)
2903
2904 time=
2905 Driver JoinedOrMissing
2906
2907 u
2908 Driver Joined Separate
2909
2910 undef
2911 Driver
2912 ; C option, but driver must not handle as "-u ndef".
2913
2914 v
2915 Common Driver Var(verbose_flag)
2916 Enable verbose output.
2917
2918 version
2919 Common Var(version_flag) RejectDriver
2920 Display the compiler's version.
2921
2922 w
2923 Common Var(inhibit_warnings)
2924 Suppress warnings.
2925
2926 wrapper
2927 Driver Separate Var(wrapper_string)
2928
2929 x
2930 Driver Joined Separate
2931
2932 shared
2933 Driver RejectNegative Negative(pie)
2934 Create a shared library.
2935
2936 shared-libgcc
2937 Driver
2938
2939 specs
2940 Driver Separate Alias(specs=)
2941
2942 specs=
2943 Driver Joined
2944
2945 static
2946 Driver
2947
2948 static-libgcc
2949 Driver
2950
2951 static-libgfortran
2952 Driver
2953 ; Documented for Fortran, but always accepted by driver.
2954
2955 static-libstdc++
2956 Driver
2957
2958 static-libgo
2959 Driver
2960 ; Documented for Go, but always accepted by driver.
2961
2962 static-libasan
2963 Driver
2964
2965 static-libtsan
2966 Driver
2967
2968 static-liblsan
2969 Driver
2970
2971 static-libubsan
2972 Driver
2973
2974 symbolic
2975 Driver
2976
2977 no-pie
2978 Driver RejectNegative Negative(shared)
2979 Don't create a position independent executable.
2980
2981 pie
2982 Driver RejectNegative Negative(no-pie)
2983 Create a position independent executable.
2984
2985 z
2986 Driver Joined Separate
2987
2988 fipa-ra
2989 Common Report Var(flag_ipa_ra) Optimization
2990 Use caller save register across calls if possible.
2991
2992 ; This comment is to ensure we retain the blank line above.