gcc/common.opt

   1 ; Options for the language- and target-independent parts of the compiler.
   2
   3 ; Copyright (C) 2003-2013 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 ; 0 means straightforward implementation of complex divide acceptable.
  50 ; 1 means wide ranges of inputs must work for complex divide.
  51 ; 2 means C99-like requirements for complex multiply and divide.
  52 Variable
  53 int flag_complex_method = 1
  54
  55 ; Nonzero if subexpressions must be evaluated from left-to-right.
  56 Variable
  57 int flag_evaluation_order = 0
  58
  59 ; Language specific warning pass for unused results.
  60 Variable
  61 bool flag_warn_unused_result = false
  62
  63 Variable
  64 int *param_values
  65
  66 ; Nonzero if we should write GIMPLE bytecode for link-time optimization.
  67 Variable
  68 int flag_generate_lto
  69
  70 ; True to warn about any objects definitions whose size is larger
  71 ; than N bytes.  Also want about function definitions whose returned
  72 ; values are larger than N bytes, where N is 'larger_than_size'.
  73 Variable
  74 bool warn_larger_than
  75
  76 Variable
  77 HOST_WIDE_INT larger_than_size
  78
  79 ; True to warn about any function whose frame size is larger
  80 ; than N bytes.
  81 Variable
  82 bool warn_frame_larger_than
  83
  84 Variable
  85 HOST_WIDE_INT frame_larger_than_size
  86
  87 ; Nonzero means we should be saving declaration info into a .X file.
  88 Variable
  89 int flag_gen_aux_info = 0
  90
  91 ; Nonzero if we are compiling code for a shared library, zero for
  92 ; executable.
  93 Variable
  94 int flag_shlib
  95
  96 ; These two are really VEC(char_p,heap) *.
  97
  98 Variable
  99 void *flag_instrument_functions_exclude_functions
 100
 101 Variable
 102 void *flag_instrument_functions_exclude_files
 103
 104 ; Generic structs (e.g. templates not explicitly specialized)
 105 ; may not have a compilation unit associated with them, and so
 106 ; may need to be treated differently from ordinary structs.
 107 ;
 108 ; Structs only handled by reference (indirectly), will also usually
 109 ; not need as much debugging information.
 110
 111 Variable
 112 enum debug_struct_file debug_struct_ordinary[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
 113
 114 Variable
 115 enum debug_struct_file debug_struct_generic[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
 116
 117 ; True if we should exit after parsing options.
 118 Variable
 119 bool exit_after_options
 120
 121 ; Type(s) of debugging information we are producing (if any).  See
 122 ; flag-types.h for the definitions of the different possible types of
 123 ; debugging information.
 124 Variable
 125 enum debug_info_type write_symbols = NO_DEBUG
 126
 127 ; Level of debugging information we are producing.  See flag-types.h
 128 ; for the definitions of the different possible levels.
 129 Variable
 130 enum debug_info_levels debug_info_level = DINFO_LEVEL_NONE
 131
 132 ; Nonzero means use GNU-only extensions in the generated symbolic
 133 ; debugging information.  Currently, this only has an effect when
 134 ; write_symbols is set to DBX_DEBUG, XCOFF_DEBUG, or DWARF_DEBUG.
 135 Variable
 136 bool use_gnu_debug_info_extensions
 137
 138 ; Original value of maximum field alignment in bytes, specified via
 139 ; -fpack-struct=<value>.
 140 Variable
 141 unsigned int initial_max_fld_align = TARGET_DEFAULT_PACK_STRUCT
 142
 143 ; Type of stack check.
 144 Variable
 145 enum stack_check_type flag_stack_check = NO_STACK_CHECK
 146
 147 ; True if stack usage information needs to be computed.
 148 Variable
 149 bool flag_stack_usage_info = false
 150
 151 ; -dA causes debug commentary information to be produced in
 152 ; the generated assembly code (to make it more readable).  This option
 153 ; is generally only of use to those who actually need to read the
 154 ; generated assembly code (perhaps while debugging the compiler itself).
 155 ; Currently, this switch is only used by dwarf2out.c; however, it is intended
 156 ; to be a catchall for printing debug information in the assembler file.
 157 Variable
 158 int flag_debug_asm
 159
 160 ; -dP causes the rtl to be emitted as a comment in assembly.
 161 Variable
 162 int flag_dump_rtl_in_asm
 163
 164 ; Whether -da was passed (used only in handle_common_deferred_options).
 165 Variable
 166 bool flag_dump_all_passed
 167
 168 ; Other flags saying which kinds of debugging dump have been requested.
 169
 170 Variable
 171 int rtl_dump_and_exit
 172
 173 Variable
 174 int flag_print_asm_name
 175
 176 ; Name of top-level original source file (what was input to cpp).
 177 ; This comes from the #-command at the beginning of the actual input.
 178 ; If there isn't any there, then this is the cc1 input file name.
 179 Variable
 180 const char *main_input_filename
 181
 182 ; Pointer to base name in main_input_filename, with directories and a
 183 ; single final extension removed, and the length of this base
 184 ; name.
 185
 186 Variable
 187 const char *main_input_basename
 188
 189 Variable
 190 int main_input_baselength
 191
 192 ; Which options have been printed by --help.
 193 Variable
 194 char *help_printed
 195
 196 ; Which enums have been printed by --help.  0 = not printed, no
 197 ; relevant options seen, 1 = relevant option seen, not yet printed, 2
 198 ; = printed.
 199 Variable
 200 char *help_enum_printed
 201
 202 ; The number of columns for --help output.
 203 Variable
 204 unsigned int help_columns
 205
 206 ; Whether this options structure has been through finish_options
 207 Variable
 208 bool flag_opts_finished
 209
 210 ; What the sanitizer should instrument
 211 Variable
 212 unsigned int flag_sanitize
 213
 214 ###
 215 Driver
 216
 217 -assemble
 218 Driver Alias(S)
 219
 220 -compile
 221 Driver Alias(c)
 222
 223 -coverage
 224 Driver Alias(coverage)
 225
 226 -debug
 227 Common Alias(g)
 228
 229 -dump
 230 Common Separate Alias(d)
 231
 232 -dump=
 233 Common Joined Alias(d)
 234
 235 -dumpbase
 236 Common Separate Alias(dumpbase)
 237
 238 -dumpdir
 239 Common Separate Alias(dumpdir)
 240
 241 -entry
 242 Driver Separate Alias(e)
 243
 244 -entry=
 245 Driver Joined Alias(e)
 246
 247 -extra-warnings
 248 Common Warning Alias(Wextra)
 249
 250 -for-assembler
 251 Driver Separate Alias(Xassembler)
 252
 253 -for-assembler=
 254 Driver JoinedOrMissing Alias(Xassembler)
 255
 256 -for-linker
 257 Driver Separate Alias(Xlinker)
 258
 259 -for-linker=
 260 Driver JoinedOrMissing Alias(Xlinker)
 261
 262 -force-link
 263 Driver Separate Alias(u)
 264
 265 -force-link=
 266 Driver Joined Alias(u)
 267
 268 -help
 269 Common Driver Var(help_flag)
 270 Display this information
 271
 272 -help=
 273 Common Driver Report Joined
 274 --help=<class>  Display descriptions of a specific class of options.  <class> is one or more of optimizers, target, warnings, undocumented, params
 275
 276 -language
 277 Driver Separate Alias(x)
 278
 279 -language=
 280 Driver Joined Alias(x)
 281
 282 -library-directory
 283 Driver Separate Alias(L)
 284
 285 -library-directory=
 286 Driver Joined Alias(L)
 287
 288 -no-canonical-prefixes
 289 Driver Alias(no-canonical-prefixes)
 290
 291 -no-standard-libraries
 292 Driver Alias(nostdlib)
 293
 294 -no-sysroot-suffix
 295 Driver Var(no_sysroot_suffix)
 296
 297 -no-warnings
 298 Common Alias(w)
 299
 300 -optimize
 301 Common Alias(O)
 302
 303 -output
 304 Common Driver Separate Alias(o) MissingArgError(missing filename after %qs)
 305
 306 -output=
 307 Common Driver Joined Alias(o) MissingArgError(missing filename after %qs)
 308
 309 -pass-exit-codes
 310 Driver Alias(pass-exit-codes)
 311
 312 -pedantic
 313 Common Alias(Wpedantic)
 314
 315 -pedantic-errors
 316 Common Alias(pedantic-errors)
 317
 318 -pie
 319 Driver Alias(pie)
 320
 321 -pipe
 322 Driver Alias(pipe)
 323
 324 -prefix
 325 Driver Separate Alias(B)
 326
 327 -prefix=
 328 Driver JoinedOrMissing Alias(B)
 329
 330 -preprocess
 331 Driver Alias(E)
 332
 333 -print-file-name
 334 Driver Separate Alias(print-file-name=)
 335
 336 -print-file-name=
 337 Driver JoinedOrMissing Alias(print-file-name=)
 338
 339 -print-libgcc-file-name
 340 Driver Alias(print-libgcc-file-name)
 341
 342 -print-multi-directory
 343 Driver Alias(print-multi-directory)
 344
 345 -print-multi-lib
 346 Driver Alias(print-multi-lib)
 347
 348 -print-multi-os-directory
 349 Driver Alias(print-multi-os-directory)
 350
 351 -print-multiarch
 352 Driver Alias(print-multiarch)
 353
 354 -print-prog-name
 355 Driver Separate Alias(print-prog-name=)
 356
 357 -print-prog-name=
 358 Driver JoinedOrMissing Alias(print-prog-name=)
 359
 360 -print-search-dirs
 361 Driver Alias(print-search-dirs)
 362
 363 -print-sysroot
 364 Driver Alias(print-sysroot)
 365
 366 -print-sysroot-headers-suffix
 367 Driver Alias(print-sysroot-headers-suffix)
 368
 369 -profile
 370 Common Alias(p)
 371
 372 -save-temps
 373 Driver Alias(save-temps)
 374
 375 -shared
 376 Driver Alias(shared)
 377
 378 -specs
 379 Driver Separate Alias(specs=)
 380
 381 -specs=
 382 Driver Joined Alias(specs=)
 383
 384 -static
 385 Driver Alias(static)
 386
 387 -symbolic
 388 Driver Alias(symbolic)
 389
 390 -target-help
 391 Common Driver
 392 Alias for --help=target
 393
 394 -time
 395 Driver Alias(time)
 396
 397 -verbose
 398 Driver Alias(v)
 399
 400 ;; The driver used to convert options such as --help into forms such
 401 ;; as -fhelp; the following four entries are for compatibility with
 402 ;; any direct uses of those (undocumented) -f forms
 403 fhelp
 404 Common Driver Alias(-help)
 405
 406 fhelp=
 407 Common Driver Joined Alias(-help=)
 408
 409 ftarget-help
 410 Common Driver Alias(-target-help)
 411
 412 fversion
 413 Common Driver Alias(-version)
 414
 415 -param
 416 Common Separate
 417 --param <param>=<value> Set parameter <param> to value.  See below for a complete list of parameters
 418
 419 -param=
 420 Common Joined Alias(-param)
 421
 422 -sysroot
 423 Driver Separate Alias(-sysroot=)
 424
 425 -sysroot=
 426 Driver JoinedOrMissing
 427
 428 -version
 429 Common Driver
 430
 431 B
 432 Driver Joined Separate
 433
 434 E
 435 Driver
 436
 437 L
 438 Driver Joined Separate
 439
 440 N
 441 Driver
 442
 443 O
 444 Common JoinedOrMissing Optimization
 445 -O<number>      Set optimization level to <number>
 446
 447 Os
 448 Common Optimization
 449 Optimize for space rather than speed
 450
 451 Ofast
 452 Common Optimization
 453 Optimize for speed disregarding exact standards compliance
 454
 455 Og
 456 Common Optimization
 457 Optimize for debugging experience rather than speed or size
 458
 459 Q
 460 Driver
 461
 462 Qn
 463 Driver Negative(Qy)
 464
 465 Qy
 466 Driver Negative(Qn)
 467
 468 R
 469 Driver Joined Separate
 470
 471 S
 472 Driver
 473
 474 T
 475 Driver Joined Separate
 476
 477 Tbss
 478 Driver Separate
 479
 480 Tbss=
 481 Driver Joined
 482
 483 Tdata
 484 Driver Separate
 485
 486 Tdata=
 487 Driver Joined
 488
 489 Ttext
 490 Driver Separate
 491
 492 Ttext=
 493 Driver Joined
 494
 495 W
 496 Common RejectNegative Warning Alias(Wextra)
 497 This switch is deprecated; use -Wextra instead
 498
 499 Wa,
 500 Driver JoinedOrMissing
 501
 502 Wl,
 503 Driver JoinedOrMissing
 504
 505 Wp,
 506 Driver JoinedOrMissing
 507
 508 Waggregate-return
 509 Common Var(warn_aggregate_return) Warning
 510 Warn about returning structures, unions or arrays
 511
 512 Waggressive-loop-optimizations
 513 Common Var(warn_aggressive_loop_optimizations) Init(1) Warning
 514 Warn if a loop with constant number of iterations triggers undefined behavior
 515
 516 Warray-bounds
 517 Common Var(warn_array_bounds) Warning
 518 Warn if an array is accessed out of bounds
 519
 520 Wattributes
 521 Common Var(warn_attributes) Init(1) Warning
 522 Warn about inappropriate attribute usage
 523
 524 Wcast-align
 525 Common Var(warn_cast_align) Warning
 526 Warn about pointer casts which increase alignment
 527
 528 Wcpp
 529 Common Var(warn_cpp) Init(1) Warning
 530 Warn when a #warning directive is encountered
 531
 532 Wdeprecated-declarations
 533 Common Var(warn_deprecated_decl) Init(1) Warning
 534 Warn about uses of __attribute__((deprecated)) declarations
 535
 536 Wdisabled-optimization
 537 Common Var(warn_disabled_optimization) Warning
 538 Warn when an optimization pass is disabled
 539
 540 Werror
 541 Common Var(warnings_are_errors)
 542 Treat all warnings as errors
 543
 544 Werror=
 545 Common Joined
 546 Treat specified warning as error
 547
 548 Wextra
 549 Common Var(extra_warnings) Warning
 550 Print extra (possibly unwanted) warnings
 551
 552 Wfatal-errors
 553 Common Var(flag_fatal_errors)
 554 Exit on the first error occurred
 555
 556 Wframe-larger-than=
 557 Common RejectNegative Joined UInteger
 558 -Wframe-larger-than=<number>    Warn if a function's stack frame requires more than <number> bytes
 559
 560 Wfree-nonheap-object
 561 Common Var(warn_free_nonheap_object) Init(1) Warning
 562 Warn when attempting to free a non-heap object
 563
 564 Winline
 565 Common Var(warn_inline) Warning
 566 Warn when an inlined function cannot be inlined
 567
 568 Winvalid-memory-model
 569 Common Var(warn_invalid_memory_model) Init(1) Warning
 570 Warn when an atomic memory model parameter is known to be outside the valid range.
 571
 572 Wlarger-than-
 573 Common RejectNegative Joined Warning Undocumented Alias(Wlarger-than=)
 574
 575 Wlarger-than=
 576 Common RejectNegative Joined UInteger Warning
 577 -Wlarger-than=<number>  Warn if an object is larger than <number> bytes
 578
 579 Wunsafe-loop-optimizations
 580 Common Var(warn_unsafe_loop_optimizations) Warning
 581 Warn if the loop cannot be optimized due to nontrivial assumptions.
 582
 583 Wmissing-noreturn
 584 Common Alias(Wsuggest-attribute=noreturn)
 585
 586 Woverflow
 587 Common Var(warn_overflow) Init(1) Warning
 588 Warn about overflow in arithmetic expressions
 589
 590 Wpacked
 591 Common Var(warn_packed) Warning
 592 Warn when the packed attribute has no effect on struct layout
 593
 594 Wpadded
 595 Common Var(warn_padded) Warning
 596 Warn when padding is required to align structure members
 597
 598 Wpedantic
 599 Common Var(pedantic) Warning
 600 Issue warnings needed for strict compliance to the standard
 601
 602 Wshadow
 603 Common Var(warn_shadow) Warning
 604 Warn when one local variable shadows another
 605
 606 Wstack-protector
 607 Common Var(warn_stack_protect) Warning
 608 Warn when not issuing stack smashing protection for some reason
 609
 610 Wstack-usage=
 611 Common Joined RejectNegative UInteger Var(warn_stack_usage) Init(-1) Warning
 612 Warn if stack usage might be larger than specified amount
 613
 614 Wstrict-aliasing
 615 Common Warning
 616 Warn about code which might break strict aliasing rules
 617
 618 Wstrict-aliasing=
 619 Common Joined RejectNegative UInteger Var(warn_strict_aliasing) Warning
 620 Warn about code which might break strict aliasing rules
 621
 622 Wstrict-overflow
 623 Common Warning
 624 Warn about optimizations that assume that signed overflow is undefined
 625
 626 Wstrict-overflow=
 627 Common Joined RejectNegative UInteger Var(warn_strict_overflow) Warning
 628 Warn about optimizations that assume that signed overflow is undefined
 629
 630 Wsuggest-attribute=const
 631 Common Var(warn_suggest_attribute_const) Warning
 632 Warn about functions which might be candidates for __attribute__((const))
 633
 634 Wsuggest-attribute=pure
 635 Common Var(warn_suggest_attribute_pure) Warning
 636 Warn about functions which might be candidates for __attribute__((pure))
 637
 638 Wsuggest-attribute=noreturn
 639 Common Var(warn_suggest_attribute_noreturn) Warning
 640 Warn about functions which might be candidates for __attribute__((noreturn))
 641
 642 Wsystem-headers
 643 Common Var(warn_system_headers) Warning
 644 Do not suppress warnings from system headers
 645
 646 Wtrampolines
 647 Common Var(warn_trampolines) Warning
 648 Warn whenever a trampoline is generated
 649
 650 Wtype-limits
 651 Common Var(warn_type_limits) Warning EnabledBy(Wextra)
 652 Warn if a comparison is always true or always false due to the limited range of the data type
 653
 654 Wuninitialized
 655 Common Var(warn_uninitialized) Warning EnabledBy(Wextra)
 656 Warn about uninitialized automatic variables
 657
 658 Wmaybe-uninitialized
 659 Common Var(warn_maybe_uninitialized) Warning EnabledBy(Wuninitialized)
 660 Warn about maybe uninitialized automatic variables
 661
 662 Wunreachable-code
 663 Common Ignore
 664 Does nothing. Preserved for backward compatibility.
 665
 666 Wunused
 667 Common Var(warn_unused) Init(0) Warning
 668 Enable all -Wunused- warnings
 669
 670 Wunused-but-set-parameter
 671 Common Var(warn_unused_but_set_parameter) Warning EnabledBy(Wunused && Wextra)
 672 Warn when a function parameter is only set, otherwise unused
 673
 674 Wunused-but-set-variable
 675 Common Var(warn_unused_but_set_variable) Warning EnabledBy(Wunused)
 676 Warn when a variable is only set, otherwise unused
 677
 678 Wunused-function
 679 Common Var(warn_unused_function) Warning EnabledBy(Wunused)
 680 Warn when a function is unused
 681
 682 Wunused-label
 683 Common Var(warn_unused_label) Warning EnabledBy(Wunused)
 684 Warn when a label is unused
 685
 686 Wunused-parameter
 687 Common Var(warn_unused_parameter) Warning EnabledBy(Wunused && Wextra)
 688 Warn when a function parameter is unused
 689
 690 Wunused-value
 691 Common Var(warn_unused_value) Warning EnabledBy(Wunused)
 692 Warn when an expression value is unused
 693
 694 Wunused-variable
 695 Common Var(warn_unused_variable) Warning EnabledBy(Wunused)
 696 Warn when a variable is unused
 697
 698 Wcoverage-mismatch
 699 Common Var(warn_coverage_mismatch) Init(1) Warning
 700 Warn in case profiles in -fprofile-use do not match
 701
 702 Wvector-operation-performance
 703 Common Var(warn_vector_operation_performance) Warning
 704 Warn when a vector operation is compiled outside the SIMD
 705
 706 Xassembler
 707 Driver Separate
 708
 709 Xlinker
 710 Driver Separate
 711
 712 Xpreprocessor
 713 Driver Separate
 714
 715 Z
 716 Driver
 717
 718 aux-info
 719 Common Separate Var(aux_info_file_name)
 720 -aux-info <file>        Emit declaration information into <file>
 721
 722 aux-info=
 723 Common Joined Alias(aux-info)
 724
 725 auxbase
 726 Common Separate RejectDriver Var(aux_base_name)
 727
 728 auxbase-strip
 729 Common Separate RejectDriver
 730
 731 coverage
 732 Driver
 733
 734 c
 735 Driver
 736
 737 d
 738 Common Joined
 739 -d<letters>     Enable dumps from specific passes of the compiler
 740
 741 dumpbase
 742 Common Separate Var(dump_base_name)
 743 -dumpbase <file>        Set the file basename to be used for dumps
 744
 745 dumpdir
 746 Common Separate Var(dump_dir_name)
 747 -dumpdir <dir>  Set the directory name to be used for dumps
 748
 749 dumpmachine
 750 Driver
 751
 752 dumpspecs
 753 Driver
 754
 755 dumpversion
 756 Driver
 757
 758 e
 759 Driver Joined Separate
 760
 761 ; This option has historically been passed down to the linker by an
 762 ; accident of a %{e*} spec, so ensure it continues to be passed down
 763 ; as a single option.  The supported option for this purpose is
 764 ; -rdynamic.  See PR 47390.
 765 export-dynamic
 766 Driver Undocumented
 767
 768 ; The version of the C++ ABI in use.  The following values are allowed:
 769 ;
 770 ; 0: The version of the ABI believed most conformant with the C++ ABI
 771 ;    specification.  This ABI may change as bugs are discovered and fixed.
 772 ;    Therefore, 0 will not necessarily indicate the same ABI in different
 773 ;    versions of G++.
 774 ;
 775 ; 1: The version of the ABI first used in G++ 3.2.
 776 ;
 777 ; 2: The version of the ABI first used in G++ 3.4 (and current default).
 778 ;
 779 ; 3: The version of the ABI that fixes the missing underscore
 780 ;    in template non-type arguments of pointer type.
 781 ;
 782 ; 4: The version of the ABI that introduces unambiguous mangling of
 783 ;    vector types.  First selectable in G++ 4.5.
 784 ;
 785 ; 5: The version of the ABI that ignores attribute const/noreturn
 786 ;    in function pointer mangling, and corrects mangling of decltype and
 787 ;    function parameters used in other parameters and the return type.
 788 ;    First selectable in G++ 4.6.
 789 ;
 790 ; 6: The version of the ABI that doesn't promote scoped enums to int and
 791 ;    changes the mangling of template argument packs, const/static_cast,
 792 ;    prefix ++ and --, and a class scope function used as a template
 793 ;    argument.
 794 ;    First selectable in G++ 4.7.
 795 ;
 796 ; 7: The version of the ABI that treats nullptr_t as a builtin type and
 797 ;    corrects the mangling of lambdas in default argument scope.
 798 ;    First selectable in G++ 4.8.
 799 ;
 800 ; 8: The version of the ABI that corrects the substitution behavior of
 801 ;    function types with function-cv-qualifiers.
 802 ;    First selectable in G++ 4.9.
 803 ;
 804 ; Additional positive integers will be assigned as new versions of
 805 ; the ABI become the default version of the ABI.
 806 fabi-version=
 807 Common Joined RejectNegative UInteger Var(flag_abi_version) Init(2)
 808
 809 faggressive-loop-optimizations
 810 Common Report Var(flag_aggressive_loop_optimizations) Optimization Init(1)
 811 Aggressively optimize loops using language constraints
 812
 813 falign-functions
 814 Common Report Var(align_functions,0) Optimization UInteger
 815 Align the start of functions
 816
 817 falign-functions=
 818 Common RejectNegative Joined UInteger Var(align_functions)
 819
 820 falign-jumps
 821 Common Report Var(align_jumps,0) Optimization UInteger
 822 Align labels which are only reached by jumping
 823
 824 falign-jumps=
 825 Common RejectNegative Joined UInteger Var(align_jumps)
 826
 827 falign-labels
 828 Common Report Var(align_labels,0) Optimization UInteger
 829 Align all labels
 830
 831 falign-labels=
 832 Common RejectNegative Joined UInteger Var(align_labels)
 833
 834 falign-loops
 835 Common Report Var(align_loops,0) Optimization UInteger
 836 Align the start of loops
 837
 838 falign-loops=
 839 Common RejectNegative Joined UInteger Var(align_loops)
 840
 841 fargument-alias
 842 Common Ignore
 843 Does nothing. Preserved for backward compatibility.
 844
 845 fargument-noalias
 846 Common Ignore
 847 Does nothing. Preserved for backward compatibility.
 848
 849 fargument-noalias-global
 850 Common Ignore
 851 Does nothing. Preserved for backward compatibility.
 852
 853 fargument-noalias-anything
 854 Common Ignore
 855 Does nothing. Preserved for backward compatibility.
 856
 857 fsanitize=
 858 Common Driver Report Joined
 859 Select what to sanitize
 860
 861 fasynchronous-unwind-tables
 862 Common Report Var(flag_asynchronous_unwind_tables) Optimization
 863 Generate unwind tables that are exact at each instruction boundary
 864
 865 fauto-inc-dec
 866 Common Report Var(flag_auto_inc_dec) Init(1)
 867 Generate auto-inc/dec instructions
 868
 869 ; -fcheck-bounds causes gcc to generate array bounds checks.
 870 ; For C, C++ and ObjC: defaults off.
 871 ; For Java: defaults to on.
 872 ; For Fortran: defaults to off.
 873 fbounds-check
 874 Common Report Var(flag_bounds_check)
 875 Generate code to check bounds before indexing arrays
 876
 877 fbranch-count-reg
 878 Common Report Var(flag_branch_on_count_reg) Init(1) Optimization
 879 Replace add, compare, branch with branch on count register
 880
 881 fbranch-probabilities
 882 Common Report Var(flag_branch_probabilities) Optimization
 883 Use profiling information for branch probabilities
 884
 885 fbranch-target-load-optimize
 886 Common Report Var(flag_branch_target_load_optimize) Optimization
 887 Perform branch target load optimization before prologue / epilogue threading
 888
 889 fbranch-target-load-optimize2
 890 Common Report Var(flag_branch_target_load_optimize2) Optimization
 891 Perform branch target load optimization after prologue / epilogue threading
 892
 893 fbtr-bb-exclusive
 894 Common Report Var(flag_btr_bb_exclusive) Optimization
 895 Restrict target load migration not to re-use registers in any basic block
 896
 897 fcall-saved-
 898 Common Joined RejectNegative Var(common_deferred_options) Defer
 899 -fcall-saved-<register> Mark <register> as being preserved across functions
 900
 901 fcall-used-
 902 Common Joined RejectNegative Var(common_deferred_options) Defer
 903 -fcall-used-<register>  Mark <register> as being corrupted by function calls
 904
 905 ; Nonzero for -fcaller-saves: allocate values in regs that need to
 906 ; be saved across function calls, if that produces overall better code.
 907 ; Optional now, so people can test it.
 908 fcaller-saves
 909 Common Report Var(flag_caller_saves) Optimization
 910 Save registers around function calls
 911
 912 fcheck-data-deps
 913 Common Report Var(flag_check_data_deps)
 914 Compare the results of several data dependence analyzers.
 915
 916 fcheck-new
 917 Common Var(flag_check_new)
 918 Check the return value of new in C++
 919
 920 fcombine-stack-adjustments
 921 Common Report Var(flag_combine_stack_adjustments) Optimization
 922 Looks for opportunities to reduce stack adjustments and stack references.
 923
 924 fcommon
 925 Common Report Var(flag_no_common,0) Optimization
 926 Do not put uninitialized globals in the common section
 927
 928 fcompare-debug
 929 Driver
 930 ; Converted by the driver to -fcompare-debug= options.
 931
 932 fcompare-debug=
 933 Common Driver JoinedOrMissing RejectNegative Var(flag_compare_debug_opt)
 934 -fcompare-debug[=<opts>]        Compile with and without e.g. -gtoggle, and compare the final-insns dump
 935
 936 fcompare-debug-second
 937 Common Driver RejectNegative Var(flag_compare_debug)
 938 Run only the second compilation of -fcompare-debug
 939
 940 fcompare-elim
 941 Common Report Var(flag_compare_elim_after_reload) Optimization
 942 Perform comparison elimination after register allocation has finished
 943
 944 fconserve-stack
 945 Common Var(flag_conserve_stack) Optimization
 946 Do not perform optimizations increasing noticeably stack usage
 947
 948 fcprop-registers
 949 Common Report Var(flag_cprop_registers) Optimization
 950 Perform a register copy-propagation optimization pass
 951
 952 fcrossjumping
 953 Common Report Var(flag_crossjumping) Optimization
 954 Perform cross-jumping optimization
 955
 956 fcse-follow-jumps
 957 Common Report Var(flag_cse_follow_jumps) Optimization
 958 When running CSE, follow jumps to their targets
 959
 960 fcse-skip-blocks
 961 Common Ignore
 962 Does nothing.  Preserved for backward compatibility.
 963
 964 fcx-limited-range
 965 Common Report Var(flag_cx_limited_range) Optimization SetByCombined
 966 Omit range reduction step when performing complex division
 967
 968 fcx-fortran-rules
 969 Common Report Var(flag_cx_fortran_rules) Optimization
 970 Complex multiplication and division follow Fortran rules
 971
 972 fdata-sections
 973 Common Report Var(flag_data_sections) Optimization
 974 Place data items into their own section
 975
 976 fdbg-cnt-list
 977 Common Report Var(common_deferred_options) Defer
 978 List all available debugging counters with their limits and counts.
 979
 980 fdbg-cnt=
 981 Common RejectNegative Joined Var(common_deferred_options) Defer
 982 -fdbg-cnt=<counter>:<limit>[,<counter>:<limit>,...]     Set the debug counter limit.
 983
 984 fdebug-prefix-map=
 985 Common Joined RejectNegative Var(common_deferred_options) Defer
 986 Map one directory name to another in debug information
 987
 988 fdebug-types-section
 989 Common Report Var(flag_debug_types_section) Init(0)
 990 Output .debug_types section when using DWARF v4 debuginfo.
 991
 992 ; Nonzero for -fdefer-pop: don't pop args after each function call
 993 ; instead save them up to pop many calls' args with one insns.
 994 fdefer-pop
 995 Common Report Var(flag_defer_pop) Optimization
 996 Defer popping functions args from stack until later
 997
 998 fdelayed-branch
 999 Common Report Var(flag_delayed_branch) Optimization
1000 Attempt to fill delay slots of branch instructions
1001
1002 fdelete-dead-exceptions
1003 Common Report Var(flag_delete_dead_exceptions) Init(0)
1004 Delete dead instructions that may throw exceptions
1005
1006 fdelete-null-pointer-checks
1007 Common Report Var(flag_delete_null_pointer_checks) Init(1) Optimization
1008 Delete useless null pointer checks
1009
1010 fdevirtualize-speculatively
1011 Common Report Var(flag_devirtualize_speculatively) Optimization
1012 Perform speculative devirtualization
1013
1014 fdevirtualize
1015 Common Report Var(flag_devirtualize) Optimization
1016 Try to convert virtual calls to direct ones.
1017
1018 fdiagnostics-show-location=
1019 Common Joined RejectNegative Enum(diagnostic_prefixing_rule)
1020 -fdiagnostics-show-location=[once|every-line]   How often to emit source location at the beginning of line-wrapped diagnostics
1021
1022 ; Required for these enum values.
1023 SourceInclude
1024 pretty-print.h
1025
1026 Enum
1027 Name(diagnostic_prefixing_rule) Type(int)
1028
1029 EnumValue
1030 Enum(diagnostic_prefixing_rule) String(once) Value(DIAGNOSTICS_SHOW_PREFIX_ONCE)
1031
1032 EnumValue
1033 Enum(diagnostic_prefixing_rule) String(every-line) Value(DIAGNOSTICS_SHOW_PREFIX_EVERY_LINE)
1034
1035 fdiagnostics-show-caret
1036 Common Var(flag_diagnostics_show_caret) Init(1)
1037 Show the source line with a caret indicating the column
1038
1039 fdiagnostics-color
1040 Common Alias(fdiagnostics-color=,always,never)
1041 ;
1042
1043 fdiagnostics-color=
1044 Common Joined RejectNegative Var(flag_diagnostics_show_color) Enum(diagnostic_color_rule) Init(DIAGNOSTICS_COLOR_NO)
1045 -fdiagnostics-color=[never|always|auto] Colorize diagnostics
1046
1047 ; Required for these enum values.
1048 SourceInclude
1049 diagnostic-color.h
1050
1051 Enum
1052 Name(diagnostic_color_rule) Type(int)
1053
1054 EnumValue
1055 Enum(diagnostic_color_rule) String(never) Value(DIAGNOSTICS_COLOR_NO)
1056
1057 EnumValue
1058 Enum(diagnostic_color_rule) String(always) Value(DIAGNOSTICS_COLOR_YES)
1059
1060 EnumValue
1061 Enum(diagnostic_color_rule) String(auto) Value(DIAGNOSTICS_COLOR_AUTO)
1062
1063 fdiagnostics-show-option
1064 Common Var(flag_diagnostics_show_option) Init(1)
1065 Amend appropriate diagnostic messages with the command line option that controls them
1066
1067 fdisable-
1068 Common Joined RejectNegative Var(common_deferred_options) Defer
1069 -fdisable-[tree|rtl|ipa]-<pass>=range1+range2 disables an optimization pass
1070
1071 fenable-
1072 Common Joined RejectNegative Var(common_deferred_options) Defer
1073 -fenable-[tree|rtl|ipa]-<pass>=range1+range2 enables an optimization pass
1074
1075 fdump-
1076 Common Joined RejectNegative Var(common_deferred_options) Defer
1077 -fdump-<type>   Dump various compiler internals to a file
1078
1079 fdump-final-insns
1080 Driver RejectNegative
1081
1082 fdump-final-insns=
1083 Common RejectNegative Joined Var(flag_dump_final_insns)
1084 -fdump-final-insns=filename     Dump to filename the insns at the end of translation
1085
1086 fdump-go-spec=
1087 Common RejectNegative Joined Var(flag_dump_go_spec)
1088 -fdump-go-spec=filename Write all declarations to file as Go code
1089
1090 fdump-noaddr
1091 Common Report Var(flag_dump_noaddr)
1092 Suppress output of addresses in debugging dumps
1093
1094 fdump-passes
1095 Common Var(flag_dump_passes) Init(0)
1096 Dump optimization passes
1097
1098 fdump-unnumbered
1099 Common Report Var(flag_dump_unnumbered)
1100 Suppress output of instruction numbers, line number notes and addresses in debugging dumps
1101
1102 fdump-unnumbered-links
1103 Common Report Var(flag_dump_unnumbered_links)
1104 Suppress output of previous and next insn numbers in debugging dumps
1105
1106 fdwarf2-cfi-asm
1107 Common Report Var(flag_dwarf2_cfi_asm) Init(HAVE_GAS_CFI_DIRECTIVE)
1108 Enable CFI tables via GAS assembler directives.
1109
1110 fearly-inlining
1111 Common Report Var(flag_early_inlining) Init(1) Optimization
1112 Perform early inlining
1113
1114 feliminate-dwarf2-dups
1115 Common Report Var(flag_eliminate_dwarf2_dups)
1116 Perform DWARF2 duplicate elimination
1117
1118 fipa-sra
1119 Common Report Var(flag_ipa_sra) Init(0) Optimization
1120 Perform interprocedural reduction of aggregates
1121
1122 feliminate-unused-debug-symbols
1123 Common Report Var(flag_debug_only_used_symbols)
1124 Perform unused type elimination in debug info
1125
1126 feliminate-unused-debug-types
1127 Common Report Var(flag_eliminate_unused_debug_types) Init(1)
1128 Perform unused type elimination in debug info
1129
1130 femit-class-debug-always
1131 Common Report Var(flag_emit_class_debug_always) Init(0)
1132 Do not suppress C++ class debug information.
1133
1134 fexceptions
1135 Common Report Var(flag_exceptions) Optimization
1136 Enable exception handling
1137
1138 fexpensive-optimizations
1139 Common Report Var(flag_expensive_optimizations) Optimization
1140 Perform a number of minor, expensive optimizations
1141
1142 fexcess-precision=
1143 Common Joined RejectNegative Enum(excess_precision) Var(flag_excess_precision_cmdline) Init(EXCESS_PRECISION_DEFAULT)
1144 -fexcess-precision=[fast|standard]      Specify handling of excess floating-point precision
1145
1146 Enum
1147 Name(excess_precision) Type(enum excess_precision) UnknownError(unknown excess precision style %qs)
1148
1149 EnumValue
1150 Enum(excess_precision) String(fast) Value(EXCESS_PRECISION_FAST)
1151
1152 EnumValue
1153 Enum(excess_precision) String(standard) Value(EXCESS_PRECISION_STANDARD)
1154
1155 ffast-math
1156 Common
1157
1158 ffat-lto-objects
1159 Common Var(flag_fat_lto_objects)
1160 Output lto objects containing both the intermediate language and binary output.
1161
1162 ffinite-math-only
1163 Common Report Var(flag_finite_math_only) Optimization SetByCombined
1164 Assume no NaNs or infinities are generated
1165
1166 ffixed-
1167 Common Joined RejectNegative Var(common_deferred_options) Defer
1168 -ffixed-<register>      Mark <register> as being unavailable to the compiler
1169
1170 ffloat-store
1171 Common Report Var(flag_float_store) Optimization
1172 Don't allocate floats and doubles in extended-precision registers
1173
1174 fforce-addr
1175 Common Ignore
1176 Does nothing.  Preserved for backward compatibility.
1177
1178 fforward-propagate
1179 Common Report Var(flag_forward_propagate) Optimization
1180 Perform a forward propagation pass on RTL
1181
1182 ffp-contract=
1183 Common Joined RejectNegative Enum(fp_contract_mode) Var(flag_fp_contract_mode) Init(FP_CONTRACT_FAST)
1184 -ffp-contract=[off|on|fast] Perform floating-point expression contraction.
1185
1186 Enum
1187 Name(fp_contract_mode) Type(enum fp_contract_mode) UnknownError(unknown floating point contraction style %qs)
1188
1189 EnumValue
1190 Enum(fp_contract_mode) String(off) Value(FP_CONTRACT_OFF)
1191
1192 ; Not implemented, fall back to conservative FP_CONTRACT_OFF.
1193 EnumValue
1194 Enum(fp_contract_mode) String(on) Value(FP_CONTRACT_OFF)
1195
1196 EnumValue
1197 Enum(fp_contract_mode) String(fast) Value(FP_CONTRACT_FAST)
1198
1199 ; Nonzero means don't put addresses of constant functions in registers.
1200 ; Used for compiling the Unix kernel, where strange substitutions are
1201 ; done on the assembly output.
1202 ffunction-cse
1203 Common Report Var(flag_no_function_cse,0)
1204 Allow function addresses to be held in registers
1205
1206 ffunction-sections
1207 Common Report Var(flag_function_sections)
1208 Place each function into its own section
1209
1210 fgcse
1211 Common Report Var(flag_gcse) Optimization
1212 Perform global common subexpression elimination
1213
1214 fgcse-lm
1215 Common Report Var(flag_gcse_lm) Init(1) Optimization
1216 Perform enhanced load motion during global common subexpression elimination
1217
1218 fgcse-sm
1219 Common Report Var(flag_gcse_sm) Init(0) Optimization
1220 Perform store motion after global common subexpression elimination
1221
1222 fgcse-las
1223 Common Report Var(flag_gcse_las) Init(0) Optimization
1224 Perform redundant load after store elimination in global common subexpression
1225 elimination
1226
1227 fgcse-after-reload
1228 Common Report Var(flag_gcse_after_reload) Optimization
1229 Perform global common subexpression elimination after register allocation
1230 has finished
1231
1232 ; This option is not documented yet as its semantics will change.
1233 fgraphite
1234 Common Report Var(flag_graphite)
1235 Enable in and out of Graphite representation
1236
1237 fgraphite-identity
1238 Common Report Var(flag_graphite_identity) Optimization
1239 Enable Graphite Identity transformation
1240
1241 fhoist-adjacent-loads
1242 Common Report Var(flag_hoist_adjacent_loads) Optimization
1243 Enable hoisting adjacent loads to encourage generating conditional move
1244 instructions
1245
1246 floop-parallelize-all
1247 Common Report Var(flag_loop_parallelize_all) Optimization
1248 Mark all loops as parallel
1249
1250 floop-strip-mine
1251 Common Report Var(flag_loop_strip_mine) Optimization
1252 Enable Loop Strip Mining transformation
1253
1254 floop-interchange
1255 Common Report Var(flag_loop_interchange) Optimization
1256 Enable Loop Interchange transformation
1257
1258 floop-block
1259 Common Report Var(flag_loop_block) Optimization
1260 Enable Loop Blocking transformation
1261
1262 fgnu-tm
1263 Common Report Var(flag_tm)
1264 Enable support for GNU transactional memory
1265
1266 floop-flatten
1267 Common Ignore
1268 Does nothing. Preserved for backward compatibility.
1269
1270 floop-nest-optimize
1271 Common Report Var(flag_loop_optimize_isl) Optimization
1272 Enable the ISL based loop nest optimizer
1273
1274 fstrict-volatile-bitfields
1275 Common Report Var(flag_strict_volatile_bitfields) Init(-1)
1276 Force bitfield accesses to match their type width
1277
1278 fguess-branch-probability
1279 Common Report Var(flag_guess_branch_prob) Optimization
1280 Enable guessing of branch probabilities
1281
1282 ; Nonzero means ignore `#ident' directives.  0 means handle them.
1283 ; Generate position-independent code for executables if possible
1284 ; On SVR4 targets, it also controls whether or not to emit a
1285 ; string identifying the compiler.
1286 fident
1287 Common Report Var(flag_no_ident,0)
1288 Process #ident directives
1289
1290 fif-conversion
1291 Common Report Var(flag_if_conversion) Optimization
1292 Perform conversion of conditional jumps to branchless equivalents
1293
1294 fif-conversion2
1295 Common Report Var(flag_if_conversion2) Optimization
1296 Perform conversion of conditional jumps to conditional execution
1297
1298 fstack-reuse=
1299 Common Joined RejectNegative Enum(stack_reuse_level) Var(flag_stack_reuse) Init(SR_ALL)
1300 -fstack-reuse=[all|named_vars|none] Set stack reuse level for local variables.
1301
1302 Enum
1303 Name(stack_reuse_level) Type(enum stack_reuse_level) UnknownError(unknown Stack Reuse Level %qs)
1304
1305 EnumValue
1306 Enum(stack_reuse_level) String(all) Value(SR_ALL)
1307
1308 EnumValue
1309 Enum(stack_reuse_level) String(named_vars) Value(SR_NAMED_VARS)
1310
1311 EnumValue
1312 Enum(stack_reuse_level) String(none) Value(SR_NONE)
1313
1314 ftree-loop-if-convert
1315 Common Report Var(flag_tree_loop_if_convert) Init(-1) Optimization
1316 Convert conditional jumps in innermost loops to branchless equivalents
1317
1318 ftree-loop-if-convert-stores
1319 Common Report Var(flag_tree_loop_if_convert_stores) Optimization
1320 Also if-convert conditional jumps containing memory writes
1321
1322 ; -finhibit-size-directive inhibits output of .size for ELF.
1323 ; This is used only for compiling crtstuff.c,
1324 ; and it may be extended to other effects
1325 ; needed for crtstuff.c on other systems.
1326 finhibit-size-directive
1327 Common Report Var(flag_inhibit_size_directive)
1328 Do not generate .size directives
1329
1330 findirect-inlining
1331 Common Report Var(flag_indirect_inlining)
1332 Perform indirect inlining
1333
1334 ; General flag to enable inlining.  Specifying -fno-inline will disable
1335 ; all inlining apart from always-inline functions.
1336 finline
1337 Common Report Var(flag_no_inline,0) Init(0) Optimization
1338 Enable inlining of function declared \"inline\", disabling disables all inlining
1339
1340 finline-small-functions
1341 Common Report Var(flag_inline_small_functions) Optimization
1342 Integrate functions into their callers when code size is known not to grow
1343
1344 finline-functions
1345 Common Report Var(flag_inline_functions) Optimization
1346 Integrate functions not declared \"inline\" into their callers when profitable
1347
1348 finline-functions-called-once
1349 Common Report Var(flag_inline_functions_called_once) Optimization
1350 Integrate functions only required by their single caller
1351
1352 finline-limit-
1353 Common RejectNegative Joined Alias(finline-limit=)
1354
1355 finline-limit=
1356 Common RejectNegative Joined UInteger
1357 -finline-limit=<number> Limit the size of inlined functions to <number>
1358
1359 finline-atomics
1360 Common Report Var(flag_inline_atomics) Init(1) Optimization
1361 Inline __atomic operations when a lock free instruction sequence is available.
1362
1363 finstrument-functions
1364 Common Report Var(flag_instrument_function_entry_exit)
1365 Instrument function entry and exit with profiling calls
1366
1367 finstrument-functions-exclude-function-list=
1368 Common RejectNegative Joined
1369 -finstrument-functions-exclude-function-list=name,...  Do not instrument listed functions
1370
1371 finstrument-functions-exclude-file-list=
1372 Common RejectNegative Joined
1373 -finstrument-functions-exclude-file-list=filename,...  Do not instrument functions listed in files
1374
1375 fipa-cp
1376 Common Report Var(flag_ipa_cp) Optimization
1377 Perform interprocedural constant propagation
1378
1379 fipa-cp-clone
1380 Common Report Var(flag_ipa_cp_clone) Optimization
1381 Perform cloning to make Interprocedural constant propagation stronger
1382
1383 fipa-profile
1384 Common Report Var(flag_ipa_profile) Init(0) Optimization
1385 Perform interprocedural profile propagation
1386
1387 fipa-pta
1388 Common Report Var(flag_ipa_pta) Init(0) Optimization
1389 Perform interprocedural points-to analysis
1390
1391 fipa-pure-const
1392 Common Report Var(flag_ipa_pure_const) Init(0) Optimization
1393 Discover pure and const functions
1394
1395 fipa-sem-equality
1396 Common Report Var(flag_ipa_sem_equality) Iinit(1) Optimization
1397 Perform Semantic function equality
1398
1399 fipa-reference
1400 Common Report Var(flag_ipa_reference) Init(0) Optimization
1401 Discover readonly and non addressable static variables
1402
1403 fipa-matrix-reorg
1404 Common Ignore
1405 Does nothing. Preserved for backward compatibility.
1406
1407 fipa-struct-reorg
1408 Common Ignore
1409 Does nothing. Preserved for backward compatibility.
1410
1411 fira-algorithm=
1412 Common Joined RejectNegative Enum(ira_algorithm) Var(flag_ira_algorithm) Init(IRA_ALGORITHM_CB)
1413 -fira-algorithm=[CB|priority] Set the used IRA algorithm
1414
1415 Enum
1416 Name(ira_algorithm) Type(enum ira_algorithm) UnknownError(unknown IRA algorithm %qs)
1417
1418 EnumValue
1419 Enum(ira_algorithm) String(CB) Value(IRA_ALGORITHM_CB)
1420
1421 EnumValue
1422 Enum(ira_algorithm) String(priority) Value(IRA_ALGORITHM_PRIORITY)
1423
1424 fira-region=
1425 Common Joined RejectNegative Enum(ira_region) Var(flag_ira_region) Init(IRA_REGION_AUTODETECT)
1426 -fira-region=[one|all|mixed] Set regions for IRA
1427
1428 Enum
1429 Name(ira_region) Type(enum ira_region) UnknownError(unknown IRA region %qs)
1430
1431 EnumValue
1432 Enum(ira_region) String(one) Value(IRA_REGION_ONE)
1433
1434 EnumValue
1435 Enum(ira_region) String(all) Value(IRA_REGION_ALL)
1436
1437 EnumValue
1438 Enum(ira_region) String(mixed) Value(IRA_REGION_MIXED)
1439
1440 fira-hoist-pressure
1441 Common Report Var(flag_ira_hoist_pressure) Init(1) Optimization
1442 Use IRA based register pressure calculation
1443 in RTL hoist optimizations.
1444
1445 fira-loop-pressure
1446 Common Report Var(flag_ira_loop_pressure)
1447 Use IRA based register pressure calculation
1448 in RTL loop optimizations.
1449
1450 fira-share-save-slots
1451 Common Report Var(flag_ira_share_save_slots) Init(1)
1452 Share slots for saving different hard registers.
1453
1454 fira-share-spill-slots
1455 Common Report Var(flag_ira_share_spill_slots) Init(1)
1456 Share stack slots for spilled pseudo-registers.
1457
1458 fira-verbose=
1459 Common RejectNegative Joined UInteger Var(flag_ira_verbose) Init(5)
1460 -fira-verbose=<number>  Control IRA's level of diagnostic messages.
1461
1462 fivopts
1463 Common Report Var(flag_ivopts) Init(1) Optimization
1464 Optimize induction variables on trees
1465
1466 fjump-tables
1467 Common Var(flag_jump_tables) Init(1) Optimization
1468 Use jump tables for sufficiently large switch statements
1469
1470 fkeep-inline-functions
1471 Common Report Var(flag_keep_inline_functions)
1472 Generate code for functions even if they are fully inlined
1473
1474 fkeep-static-consts
1475 Common Report Var(flag_keep_static_consts) Init(1)
1476 Emit static const variables even if they are not used
1477
1478 fleading-underscore
1479 Common Report Var(flag_leading_underscore) Init(-1)
1480 Give external symbols a leading underscore
1481
1482 floop-optimize
1483 Common Ignore
1484 Does nothing.  Preserved for backward compatibility.
1485
1486 flto
1487 Common
1488 Enable link-time optimization.
1489
1490 flto=
1491 Common RejectNegative Joined Var(flag_lto)
1492 Link-time optimization with number of parallel jobs or jobserver.
1493
1494 flto-partition=1to1
1495 Common Var(flag_lto_partition_1to1)
1496 Partition symbols and vars at linktime based on object files they originate from
1497
1498 flto-partition=balanced
1499 Common Var(flag_lto_partition_balanced)
1500 Partition functions and vars at linktime into approximately same sized buckets
1501
1502 flto-partition=max
1503 Common Var(flag_lto_partition_max)
1504 Put every symbol into separate partition
1505
1506 flto-partition=none
1507 Common Var(flag_lto_partition_none)
1508 Disable partioning and streaming
1509
1510 ; The initial value of -1 comes from Z_DEFAULT_COMPRESSION in zlib.h.
1511 flto-compression-level=
1512 Common Joined RejectNegative UInteger Var(flag_lto_compression_level) Init(-1)
1513 -flto-compression-level=<number>        Use zlib compression level <number> for IL
1514
1515 flto-report
1516 Common Report Var(flag_lto_report) Init(0)
1517 Report various link-time optimization statistics
1518
1519 flto-report-wpa
1520 Common Report Var(flag_lto_report_wpa) Init(0)
1521 Report various link-time optimization statistics for WPA only
1522
1523 fmath-errno
1524 Common Report Var(flag_errno_math) Init(1) Optimization SetByCombined
1525 Set errno after built-in math functions
1526
1527 fmax-errors=
1528 Common Joined RejectNegative UInteger Var(flag_max_errors)
1529 -fmax-errors=<number>   Maximum number of errors to report
1530
1531 fmem-report
1532 Common Report Var(mem_report)
1533 Report on permanent memory allocation
1534
1535 fmem-report-wpa
1536 Common Report Var(mem_report_wpa)
1537 Report on permanent memory allocation in WPA only
1538
1539 ; This will attempt to merge constant section constants, if 1 only
1540 ; string constants and constants from constant pool, if 2 also constant
1541 ; variables.
1542 fmerge-all-constants
1543 Common Report Var(flag_merge_constants,2) Init(1) Optimization
1544 Attempt to merge identical constants and constant variables
1545
1546 fmerge-constants
1547 Common Report Var(flag_merge_constants,1) Optimization
1548 Attempt to merge identical constants across compilation units
1549
1550 fmerge-debug-strings
1551 Common Report Var(flag_merge_debug_strings) Init(1)
1552 Attempt to merge identical debug strings across compilation units
1553
1554 fmessage-length=
1555 Common RejectNegative Joined UInteger
1556 -fmessage-length=<number>       Limit diagnostics to <number> characters per line.  0 suppresses line-wrapping
1557
1558 fmodulo-sched
1559 Common Report Var(flag_modulo_sched) Optimization
1560 Perform SMS based modulo scheduling before the first scheduling pass
1561
1562 fmodulo-sched-allow-regmoves
1563 Common Report Var(flag_modulo_sched_allow_regmoves)
1564 Perform SMS based modulo scheduling with register moves allowed
1565
1566 fmove-loop-invariants
1567 Common Report Var(flag_move_loop_invariants) Init(1) Optimization
1568 Move loop invariant computations out of loops
1569
1570 fdce
1571 Common Var(flag_dce) Init(1) Optimization
1572 Use the RTL dead code elimination pass
1573
1574 fdse
1575 Common Var(flag_dse) Init(1) Optimization
1576 Use the RTL dead store elimination pass
1577
1578 freschedule-modulo-scheduled-loops
1579 Common Report Var(flag_resched_modulo_sched) Optimization
1580 Enable/Disable the traditional scheduling in loops that already passed modulo scheduling
1581
1582 fnon-call-exceptions
1583 Common Report Var(flag_non_call_exceptions) Optimization
1584 Support synchronous non-call exceptions
1585
1586 fomit-frame-pointer
1587 Common Report Var(flag_omit_frame_pointer) Optimization
1588 When possible do not generate stack frames
1589
1590 fopt-info
1591 Common Report Var(flag_opt_info) Optimization
1592 Enable all optimization info dumps on stderr
1593
1594 fopt-info-
1595 Common Joined RejectNegative Var(common_deferred_options) Defer
1596 -fopt-info[-<type>=filename]    Dump compiler optimization details
1597
1598 foptimize-register-move
1599 Common Ignore
1600 Does nothing. Preserved for backward compatibility.
1601
1602 foptimize-sibling-calls
1603 Common Report Var(flag_optimize_sibling_calls) Optimization
1604 Optimize sibling and tail recursive calls
1605
1606 fpartial-inlining
1607 Common Report Var(flag_partial_inlining)
1608 Perform partial inlining
1609
1610 fpre-ipa-mem-report
1611 Common Report Var(pre_ipa_mem_report)
1612 Report on memory allocation before interprocedural optimization
1613
1614 fpost-ipa-mem-report
1615 Common Report Var(post_ipa_mem_report)
1616 Report on memory allocation before interprocedural optimization
1617
1618 fpack-struct
1619 Common Report Var(flag_pack_struct) Optimization
1620 Pack structure members together without holes
1621
1622 fpack-struct=
1623 Common RejectNegative Joined UInteger Optimization
1624 -fpack-struct=<number>  Set initial maximum structure member alignment
1625
1626 fpcc-struct-return
1627 Common Report Var(flag_pcc_struct_return,1) Init(DEFAULT_PCC_STRUCT_RETURN)
1628 Return small aggregates in memory, not registers
1629
1630 fpeel-loops
1631 Common Report Var(flag_peel_loops) Optimization
1632 Perform loop peeling
1633
1634 fpeephole
1635 Common Report Var(flag_no_peephole,0) Optimization
1636 Enable machine specific peephole optimizations
1637
1638 fpeephole2
1639 Common Report Var(flag_peephole2) Optimization
1640 Enable an RTL peephole pass before sched2
1641
1642 fPIC
1643 Common Report Var(flag_pic,2) Negative(fPIE)
1644 Generate position-independent code if possible (large mode)
1645
1646 fPIE
1647 Common Report Var(flag_pie,2) Negative(fpic)
1648 Generate position-independent code for executables if possible (large mode)
1649
1650 fpic
1651 Common Report Var(flag_pic,1) Negative(fpie)
1652 Generate position-independent code if possible (small mode)
1653
1654 fpie
1655 Common Report Var(flag_pie,1) Negative(fPIC)
1656 Generate position-independent code for executables if possible (small mode)
1657
1658 fplugin=
1659 Common Joined RejectNegative Var(common_deferred_options) Defer
1660 Specify a plugin to load
1661
1662 fplugin-arg-
1663 Common Joined RejectNegative Var(common_deferred_options) Defer
1664 -fplugin-arg-<name>-<key>[=<value>]     Specify argument <key>=<value> for plugin <name>
1665
1666 fpredictive-commoning
1667 Common Report Var(flag_predictive_commoning) Optimization
1668 Run predictive commoning optimization.
1669
1670 fprefetch-loop-arrays
1671 Common Report Var(flag_prefetch_loop_arrays) Init(-1) Optimization
1672 Generate prefetch instructions, if available, for arrays in loops
1673
1674 fprofile
1675 Common Report Var(profile_flag)
1676 Enable basic program profiling code
1677
1678 fprofile-arcs
1679 Common Report Var(profile_arc_flag)
1680 Insert arc-based program profiling code
1681
1682 fprofile-dir=
1683 Common Joined RejectNegative Var(profile_data_prefix)
1684 Set the top-level directory for storing the profile data.
1685 The default is 'pwd'.
1686
1687 fprofile-correction
1688 Common Report Var(flag_profile_correction)
1689 Enable correction of flow inconsistent profile data input
1690
1691 fprofile-generate
1692 Common
1693 Enable common options for generating profile info for profile feedback directed optimizations
1694
1695 fprofile-generate=
1696 Common Joined RejectNegative
1697 Enable common options for generating profile info for profile feedback directed optimizations, and set -fprofile-dir=
1698
1699 fprofile-use
1700 Common Var(flag_profile_use)
1701 Enable common options for performing profile feedback directed optimizations
1702
1703 fprofile-use=
1704 Common Joined RejectNegative
1705 Enable common options for performing profile feedback directed optimizations, and set -fprofile-dir=
1706
1707 fprofile-values
1708 Common Report Var(flag_profile_values)
1709 Insert code to profile values of expressions
1710
1711 fprofile-report
1712 Common Report Var(profile_report)
1713 Report on consistency of profile
1714
1715 fprofile-reorder-functions
1716 Common Report Var(flag_profile_reorder_functions)
1717 Enable function reordering that improves code placement
1718
1719 frandom-seed
1720 Common Var(common_deferred_options) Defer
1721
1722 frandom-seed=
1723 Common Joined RejectNegative Var(common_deferred_options) Defer
1724 -frandom-seed=<string>  Make compile reproducible using <string>
1725
1726 ; This switch causes the command line that was used to create an
1727 ; object file to be recorded into the object file.  The exact format
1728 ; of this recording is target and binary file format dependent.
1729 ; It is related to the -fverbose-asm switch, but that switch only
1730 ; records information in the assembler output file as comments, so
1731 ; they never reach the object file.
1732 frecord-gcc-switches
1733 Common Report Var(flag_record_gcc_switches)
1734 Record gcc command line switches in the object file.
1735
1736 freg-struct-return
1737 Common Report Var(flag_pcc_struct_return,0) Optimization
1738 Return small aggregates in registers
1739
1740 fregmove
1741 Common Ignore
1742 Does nothing. Preserved for backward compatibility.
1743
1744 flive-range-shrinkage
1745 Common Report Var(flag_live_range_shrinkage) Init(0) Optimization
1746 Relief of register pressure through live range shrinkage
1747
1748 frename-registers
1749 Common Report Var(flag_rename_registers) Init(2) Optimization
1750 Perform a register renaming optimization pass
1751
1752 freorder-blocks
1753 Common Report Var(flag_reorder_blocks) Optimization
1754 Reorder basic blocks to improve code placement
1755
1756 freorder-blocks-and-partition
1757 Common Report Var(flag_reorder_blocks_and_partition) Optimization
1758 Reorder basic blocks and partition into hot and cold sections
1759
1760 freorder-functions
1761 Common Report Var(flag_reorder_functions) Optimization
1762 Reorder functions to improve code placement
1763
1764 frerun-cse-after-loop
1765 Common Report Var(flag_rerun_cse_after_loop) Optimization
1766 Add a common subexpression elimination pass after loop optimizations
1767
1768 frerun-loop-opt
1769 Common Ignore
1770 Does nothing.  Preserved for backward compatibility.
1771
1772 frounding-math
1773 Common Report Var(flag_rounding_math) Optimization SetByCombined
1774 Disable optimizations that assume default FP rounding behavior
1775
1776 fsched-interblock
1777 Common Report Var(flag_schedule_interblock) Init(1) Optimization
1778 Enable scheduling across basic blocks
1779
1780 fsched-pressure
1781 Common Report Var(flag_sched_pressure) Init(0) Optimization
1782 Enable register pressure sensitive insn scheduling
1783
1784 fsched-spec
1785 Common Report Var(flag_schedule_speculative) Init(1) Optimization
1786 Allow speculative motion of non-loads
1787
1788 fsched-spec-load
1789 Common Report Var(flag_schedule_speculative_load) Optimization
1790 Allow speculative motion of some loads
1791
1792 fsched-spec-load-dangerous
1793 Common Report Var(flag_schedule_speculative_load_dangerous) Optimization
1794 Allow speculative motion of more loads
1795
1796 fsched-verbose=
1797 Common RejectNegative Joined UInteger Var(sched_verbose_param)
1798 -fsched-verbose=<number>        Set the verbosity level of the scheduler
1799
1800 fsched2-use-superblocks
1801 Common Report Var(flag_sched2_use_superblocks) Optimization
1802 If scheduling post reload, do superblock scheduling
1803
1804 fsched2-use-traces
1805 Common Ignore
1806 Does nothing.  Preserved for backward compatibility.
1807
1808 fschedule-insns
1809 Common Report Var(flag_schedule_insns) Optimization
1810 Reschedule instructions before register allocation
1811
1812 fschedule-insns2
1813 Common Report Var(flag_schedule_insns_after_reload) Optimization
1814 Reschedule instructions after register allocation
1815
1816 ; This flag should be on when a target implements non-trivial
1817 ; scheduling hooks, maybe saving some information for its own sake.
1818 ; On IA64, for example, this is used for correct bundling.
1819 fselective-scheduling
1820 Common Report Var(flag_selective_scheduling) Optimization
1821 Schedule instructions using selective scheduling algorithm
1822
1823 fselective-scheduling2
1824 Common Report Var(flag_selective_scheduling2) Optimization
1825 Run selective scheduling after reload
1826
1827 fsel-sched-pipelining
1828 Common Report Var(flag_sel_sched_pipelining) Init(0) Optimization
1829 Perform software pipelining of inner loops during selective scheduling
1830
1831 fsel-sched-pipelining-outer-loops
1832 Common Report Var(flag_sel_sched_pipelining_outer_loops) Init(0) Optimization
1833 Perform software pipelining of outer loops during selective scheduling
1834
1835 fsel-sched-reschedule-pipelined
1836 Common Report Var(flag_sel_sched_reschedule_pipelined) Init(0) Optimization
1837 Reschedule pipelined regions without pipelining
1838
1839 ; sched_stalled_insns means that insns can be moved prematurely from the queue
1840 ; of stalled insns into the ready list.
1841 fsched-stalled-insns
1842 Common Report Var(flag_sched_stalled_insns) Optimization UInteger
1843 Allow premature scheduling of queued insns
1844
1845 fsched-stalled-insns=
1846 Common RejectNegative Joined UInteger
1847 -fsched-stalled-insns=<number>  Set number of queued insns that can be prematurely scheduled
1848
1849 ; sched_stalled_insns_dep controls how many recently scheduled cycles will
1850 ; be examined for a dependency on a stalled insn that is candidate for
1851 ; premature removal from the queue of stalled insns into the ready list (has
1852 ; an effect only if the flag 'sched_stalled_insns' is set).
1853 fsched-stalled-insns-dep
1854 Common Report Var(flag_sched_stalled_insns_dep,1) Init(1) Optimization UInteger
1855 Set dependence distance checking in premature scheduling of queued insns
1856
1857 fsched-stalled-insns-dep=
1858 Common RejectNegative Joined UInteger
1859 -fsched-stalled-insns-dep=<number>      Set dependence distance checking in premature scheduling of queued insns
1860
1861 fsched-group-heuristic
1862 Common Report Var(flag_sched_group_heuristic) Init(1) Optimization
1863 Enable the group heuristic in the scheduler
1864
1865 fsched-critical-path-heuristic
1866 Common Report Var(flag_sched_critical_path_heuristic) Init(1) Optimization
1867 Enable the critical path heuristic in the scheduler
1868
1869 fsched-spec-insn-heuristic
1870 Common Report Var(flag_sched_spec_insn_heuristic) Init(1) Optimization
1871 Enable the speculative instruction heuristic in the scheduler
1872
1873 fsched-rank-heuristic
1874 Common Report Var(flag_sched_rank_heuristic) Init(1) Optimization
1875 Enable the rank heuristic in the scheduler
1876
1877 fsched-last-insn-heuristic
1878 Common Report Var(flag_sched_last_insn_heuristic) Init(1) Optimization
1879 Enable the last instruction heuristic in the scheduler
1880
1881 fsched-dep-count-heuristic
1882 Common Report Var(flag_sched_dep_count_heuristic) Init(1) Optimization
1883 Enable the dependent count heuristic in the scheduler
1884
1885 fsection-anchors
1886 Common Report Var(flag_section_anchors) Optimization
1887 Access data in the same section from shared anchor points
1888
1889 fsee
1890 Common Ignore
1891 Does nothing.  Preserved for backward compatibility.
1892
1893 fzee
1894 Common Ignore
1895 Does nothing.  Preserved for backward compatibility.
1896
1897 free
1898 Common Report Var(flag_ree) Init(0)
1899 Turn on Redundant Extensions Elimination pass.
1900
1901 fshow-column
1902 Common Report Var(flag_show_column) Init(1)
1903 Show column numbers in diagnostics, when available.  Default on
1904
1905 fshrink-wrap
1906 Common Report Var(flag_shrink_wrap) Optimization
1907 Emit function prologues only before parts of the function that need it,
1908 rather than at the top of the function.
1909
1910 fsignaling-nans
1911 Common Report Var(flag_signaling_nans) Optimization SetByCombined
1912 Disable optimizations observable by IEEE signaling NaNs
1913
1914 fsigned-zeros
1915 Common Report Var(flag_signed_zeros) Init(1) Optimization SetByCombined
1916 Disable floating point optimizations that ignore the IEEE signedness of zero
1917
1918 fsingle-precision-constant
1919 Common Report Var(flag_single_precision_constant) Optimization
1920 Convert floating point constants to single precision constants
1921
1922 fsplit-ivs-in-unroller
1923 Common Report Var(flag_split_ivs_in_unroller) Init(1) Optimization
1924 Split lifetimes of induction variables when loops are unrolled
1925
1926 fsplit-stack
1927 Common Report Var(flag_split_stack) Init(-1)
1928 Generate discontiguous stack frames
1929
1930 fsplit-wide-types
1931 Common Report Var(flag_split_wide_types) Optimization
1932 Split wide types into independent registers
1933
1934 fvariable-expansion-in-unroller
1935 Common Report Var(flag_variable_expansion_in_unroller) Optimization
1936 Apply variable expansion when loops are unrolled
1937
1938 fstack-check=
1939 Common Report RejectNegative Joined
1940 -fstack-check=[no|generic|specific]     Insert stack checking code into the program
1941
1942 fstack-check
1943 Common Alias(fstack-check=, specific, no)
1944 Insert stack checking code into the program.  Same as -fstack-check=specific
1945
1946 fstack-limit
1947 Common Var(common_deferred_options) Defer
1948
1949 fstack-limit-register=
1950 Common RejectNegative Joined Var(common_deferred_options) Defer
1951 -fstack-limit-register=<register>       Trap if the stack goes past <register>
1952
1953 fstack-limit-symbol=
1954 Common RejectNegative Joined Var(common_deferred_options) Defer
1955 -fstack-limit-symbol=<name>     Trap if the stack goes past symbol <name>
1956
1957 fstack-protector
1958 Common Report Var(flag_stack_protect, 1)
1959 Use propolice as a stack protection method
1960
1961 fstack-protector-all
1962 Common Report RejectNegative Var(flag_stack_protect, 2)
1963 Use a stack protection method for every function
1964
1965 fstack-protector-strong
1966 Common Report RejectNegative Var(flag_stack_protect, 3)
1967 Use a smart stack protection method for certain functions
1968
1969 fstack-usage
1970 Common RejectNegative Var(flag_stack_usage)
1971 Output stack usage information on a per-function basis
1972
1973 fstrength-reduce
1974 Common Ignore
1975 Does nothing.  Preserved for backward compatibility.
1976
1977 ; Nonzero if we should do (language-dependent) alias analysis.
1978 ; Typically, this analysis will assume that expressions of certain
1979 ; types do not alias expressions of certain other types.  Only used
1980 ; if alias analysis (in general) is enabled.
1981 fstrict-aliasing
1982 Common Report Var(flag_strict_aliasing) Optimization
1983 Assume strict aliasing rules apply
1984
1985 fstrict-overflow
1986 Common Report Var(flag_strict_overflow)
1987 Treat signed overflow as undefined
1988
1989 fsync-libcalls
1990 Common Report Var(flag_sync_libcalls) Init(1)
1991 Implement __atomic operations via libcalls to legacy __sync functions
1992
1993 fsyntax-only
1994 Common Report Var(flag_syntax_only)
1995 Check for syntax errors, then stop
1996
1997 ftest-coverage
1998 Common Report Var(flag_test_coverage)
1999 Create data files needed by \"gcov\"
2000
2001 fthread-jumps
2002 Common Report Var(flag_thread_jumps) Optimization
2003 Perform jump threading optimizations
2004
2005 ftime-report
2006 Common Report Var(time_report)
2007 Report the time taken by each compiler pass
2008
2009 ftls-model=
2010 Common Joined RejectNegative Enum(tls_model) Var(flag_tls_default) Init(TLS_MODEL_GLOBAL_DYNAMIC)
2011 -ftls-model=[global-dynamic|local-dynamic|initial-exec|local-exec]      Set the default thread-local storage code generation model
2012
2013 Enum
2014 Name(tls_model) Type(enum tls_model) UnknownError(unknown TLS model %qs)
2015
2016 EnumValue
2017 Enum(tls_model) String(global-dynamic) Value(TLS_MODEL_GLOBAL_DYNAMIC)
2018
2019 EnumValue
2020 Enum(tls_model) String(local-dynamic) Value(TLS_MODEL_LOCAL_DYNAMIC)
2021
2022 EnumValue
2023 Enum(tls_model) String(initial-exec) Value(TLS_MODEL_INITIAL_EXEC)
2024
2025 EnumValue
2026 Enum(tls_model) String(local-exec) Value(TLS_MODEL_LOCAL_EXEC)
2027
2028 ftoplevel-reorder
2029 Common Report Var(flag_toplevel_reorder) Init(2) Optimization
2030 Reorder top level functions, variables, and asms
2031
2032 ftracer
2033 Common Report Var(flag_tracer)
2034 Perform superblock formation via tail duplication
2035
2036 ; Zero means that floating-point math operations cannot generate a
2037 ; (user-visible) trap.  This is the case, for example, in nonstop
2038 ; IEEE 754 arithmetic.
2039 ftrapping-math
2040 Common Report Var(flag_trapping_math) Init(1) Optimization SetByCombined
2041 Assume floating-point operations can trap
2042
2043 ftrapv
2044 Common Report Var(flag_trapv) Optimization
2045 Trap for signed overflow in addition, subtraction and multiplication
2046
2047 ftree-ccp
2048 Common Report Var(flag_tree_ccp) Optimization
2049 Enable SSA-CCP optimization on trees
2050
2051 ftree-bit-ccp
2052 Common Report Var(flag_tree_bit_ccp) Optimization
2053 Enable SSA-BIT-CCP optimization on trees
2054
2055 ftree-store-ccp
2056 Common Ignore
2057 Does nothing.  Preserved for backward compatibility.
2058
2059 ftree-ch
2060 Common Report Var(flag_tree_ch) Optimization
2061 Enable loop header copying on trees
2062
2063 ftree-coalesce-inlined-vars
2064 Common Report Var(flag_ssa_coalesce_vars,1) Init(2) RejectNegative Optimization
2065 Enable coalescing of copy-related user variables that are inlined
2066
2067 ftree-coalesce-vars
2068 Common Report Var(flag_ssa_coalesce_vars,2) Optimization
2069 Enable coalescing of all copy-related user variables
2070
2071 ftree-copyrename
2072 Common Report Var(flag_tree_copyrename) Optimization
2073 Replace SSA temporaries with better names in copies
2074
2075 ftree-copy-prop
2076 Common Report Var(flag_tree_copy_prop) Optimization
2077 Enable copy propagation on trees
2078
2079 ftree-store-copy-prop
2080 Common Ignore
2081 Does nothing.  Preserved for backward compatibility.
2082
2083 ftree-cselim
2084 Common Report Var(flag_tree_cselim) Init(2) Optimization
2085 Transform condition stores into unconditional ones
2086
2087 ftree-switch-conversion
2088 Common Report Var(flag_tree_switch_conversion) Optimization
2089 Perform conversions of switch initializations.
2090
2091 ftree-dce
2092 Common Report Var(flag_tree_dce) Optimization
2093 Enable SSA dead code elimination optimization on trees
2094
2095 ftree-dominator-opts
2096 Common Report Var(flag_tree_dom) Optimization
2097 Enable dominator optimizations
2098
2099 ftree-tail-merge
2100 Common Report Var(flag_tree_tail_merge) Optimization
2101 Enable tail merging on trees
2102
2103 ftree-dse
2104 Common Report Var(flag_tree_dse) Optimization
2105 Enable dead store elimination
2106
2107 ftree-forwprop
2108 Common Report Var(flag_tree_forwprop) Init(1) Optimization
2109 Enable forward propagation on trees
2110
2111 ftree-fre
2112 Common Report Var(flag_tree_fre) Optimization
2113 Enable Full Redundancy Elimination (FRE) on trees
2114
2115 foptimize-strlen
2116 Common Report Var(flag_optimize_strlen) Optimization
2117 Enable string length optimizations on trees
2118
2119 fisolate-erroneous-paths-dereference
2120 Common Report Var(flag_isolate_erroneous_paths_dereference) Optimization
2121 Detect paths which trigger erroneous or undefined behaviour due to
2122 dereferencing a NULL pointer.  Isolate those paths from the main control
2123 flow and turn the statement with erroneous or undefined behaviour into a trap.
2124
2125 fisolate-erroneous-paths-attribute
2126 Common Report Var(flag_isolate_erroneous_paths_attribute) Optimization
2127 Detect paths which trigger erroneous or undefined behaviour due a NULL value
2128 being used in a way which is forbidden by a returns_nonnull or nonnull
2129 attribute.  Isolate those paths from the main control flow and turn the
2130 statement with erroneous or undefined behaviour into a trap.
2131
2132 ftree-loop-distribution
2133 Common Report Var(flag_tree_loop_distribution) Optimization
2134 Enable loop distribution on trees
2135
2136 ftree-loop-distribute-patterns
2137 Common Report Var(flag_tree_loop_distribute_patterns) Optimization
2138 Enable loop distribution for patterns transformed into a library call
2139
2140 ftree-loop-im
2141 Common Report Var(flag_tree_loop_im) Init(1) Optimization
2142 Enable loop invariant motion on trees
2143
2144 ftree-loop-linear
2145 Common Alias(floop-interchange)
2146 Enable loop interchange transforms.  Same as -floop-interchange
2147
2148 ftree-loop-ivcanon
2149 Common Report Var(flag_tree_loop_ivcanon) Init(1) Optimization
2150 Create canonical induction variables in loops
2151
2152 ftree-loop-optimize
2153 Common Report Var(flag_tree_loop_optimize) Init(1) Optimization
2154 Enable loop optimizations on tree level
2155
2156 ftree-parallelize-loops=
2157 Common Report Joined RejectNegative UInteger Var(flag_tree_parallelize_loops) Init(1)
2158 Enable automatic parallelization of loops
2159
2160 ftree-phiprop
2161 Common Report Var(flag_tree_phiprop) Init(1) Optimization
2162 Enable hoisting loads from conditional pointers.
2163
2164 ftree-pre
2165 Common Report Var(flag_tree_pre) Optimization
2166 Enable SSA-PRE optimization on trees
2167
2168 ftree-partial-pre
2169 Common Report Var(flag_tree_partial_pre) Optimization
2170 In SSA-PRE optimization on trees, enable partial-partial redundancy elimination
2171
2172 ftree-pta
2173 Common Report Var(flag_tree_pta) Init(1) Optimization
2174 Perform function-local points-to analysis on trees.
2175
2176 ftree-reassoc
2177 Common Report Var(flag_tree_reassoc) Init(1) Optimization
2178 Enable reassociation on tree level
2179
2180 ftree-salias
2181 Common Ignore
2182 Does nothing.  Preserved for backward compatibility.
2183
2184 ftree-sink
2185 Common Report Var(flag_tree_sink) Optimization
2186 Enable SSA code sinking on trees
2187
2188 ftree-slsr
2189 Common Report Var(flag_tree_slsr) Optimization
2190 Perform straight-line strength reduction
2191
2192 ftree-sra
2193 Common Report Var(flag_tree_sra) Optimization
2194 Perform scalar replacement of aggregates
2195
2196 ftree-ter
2197 Common Report Var(flag_tree_ter) Optimization
2198 Replace temporary expressions in the SSA->normal pass
2199
2200 ftree-lrs
2201 Common Report Var(flag_tree_live_range_split) Optimization
2202 Perform live range splitting during the SSA->normal pass
2203
2204 ftree-vrp
2205 Common Report Var(flag_tree_vrp) Init(0) Optimization
2206 Perform Value Range Propagation on trees
2207
2208 funit-at-a-time
2209 Common Report Var(flag_unit_at_a_time) Init(1) Optimization
2210 Compile whole compilation unit at a time
2211
2212 funroll-loops
2213 Common Report Var(flag_unroll_loops) Optimization
2214 Perform loop unrolling when iteration count is known
2215
2216 funroll-all-loops
2217 Common Report Var(flag_unroll_all_loops) Optimization
2218 Perform loop unrolling for all loops
2219
2220 ; Nonzero means that loop optimizer may assume that the induction variables
2221 ; that control loops do not overflow and that the loops with nontrivial
2222 ; exit condition are not infinite
2223 funsafe-loop-optimizations
2224 Common Report Var(flag_unsafe_loop_optimizations) Optimization
2225 Allow loop optimizations to assume that the loops behave in normal way
2226
2227 fassociative-math
2228 Common Report Var(flag_associative_math) SetByCombined
2229 Allow optimization for floating-point arithmetic which may change the
2230 result of the operation due to rounding.
2231
2232 freciprocal-math
2233 Common Report Var(flag_reciprocal_math) SetByCombined
2234 Same as -fassociative-math for expressions which include division.
2235
2236 ; Nonzero means that unsafe floating-point math optimizations are allowed
2237 ; for the sake of speed.  IEEE compliance is not guaranteed, and operations
2238 ; are allowed to assume that their arguments and results are "normal"
2239 ; (e.g., nonnegative for SQRT).
2240 funsafe-math-optimizations
2241 Common Report Var(flag_unsafe_math_optimizations) Optimization SetByCombined
2242 Allow math optimizations that may violate IEEE or ISO standards
2243
2244 funswitch-loops
2245 Common Report Var(flag_unswitch_loops) Optimization
2246 Perform loop unswitching
2247
2248 funwind-tables
2249 Common Report Var(flag_unwind_tables) Optimization
2250 Just generate unwind tables for exception handling
2251
2252 fuse-ld=bfd
2253 Common Driver Negative(fuse-ld=gold)
2254 Use the bfd linker instead of the default linker
2255
2256 fuse-ld=gold
2257 Common Driver Negative(fuse-ld=bfd)
2258 Use the gold linker instead of the default linker
2259
2260 fuse-linker-plugin
2261 Common Undocumented Var(flag_use_linker_plugin)
2262
2263 ; Positive if we should track variables, negative if we should run
2264 ; the var-tracking pass only to discard debug annotations, zero if
2265 ; we're not to run it.  When flag_var_tracking == 2 (AUTODETECT_VALUE) it
2266 ; will be set according to optimize, debug_info_level and debug_hooks
2267 ; in process_options ().
2268 fvar-tracking
2269 Common Report Var(flag_var_tracking) Init(2) Optimization
2270 Perform variable tracking
2271
2272 ; Positive if we should track variables at assignments, negative if
2273 ; we should run the var-tracking pass only to discard debug
2274 ; annotations.  When flag_var_tracking_assignments ==
2275 ; AUTODETECT_VALUE it will be set according to flag_var_tracking.
2276 fvar-tracking-assignments
2277 Common Report Var(flag_var_tracking_assignments) Init(2) Optimization
2278 Perform variable tracking by annotating assignments
2279
2280 ; Nonzero if we should toggle flag_var_tracking_assignments after
2281 ; processing options and computing its default.  */
2282 fvar-tracking-assignments-toggle
2283 Common Report Var(flag_var_tracking_assignments_toggle) Optimization
2284 Toggle -fvar-tracking-assignments
2285
2286 ; Positive if we should track uninitialized variables, negative if
2287 ; we should run the var-tracking pass only to discard debug
2288 ; annotations.  When flag_var_tracking_uninit == AUTODETECT_VALUE it
2289 ; will be set according to flag_var_tracking.
2290 fvar-tracking-uninit
2291 Common Report Var(flag_var_tracking_uninit) Optimization
2292 Perform variable tracking and also tag variables that are uninitialized
2293
2294 ftree-vectorize
2295 Common Report Var(flag_tree_vectorize) Optimization
2296 Enable vectorization on trees
2297
2298 ftree-vectorizer-verbose=
2299 Common Joined RejectNegative Ignore
2300 Does nothing.  Preserved for backward compatibility.
2301
2302 ftree-loop-vectorize
2303 Common Report Var(flag_tree_loop_vectorize) Optimization
2304 Enable loop vectorization on trees
2305
2306 ftree-slp-vectorize
2307 Common Report Var(flag_tree_slp_vectorize) Optimization
2308 Enable basic block vectorization (SLP) on trees
2309
2310 fvect-cost-model=
2311 Common Joined RejectNegative Enum(vect_cost_model) Var(flag_vect_cost_model) Init(VECT_COST_MODEL_DEFAULT)
2312 Specifies the cost model for vectorization
2313
2314 fsimd-cost-model=
2315 Common Joined RejectNegative Enum(vect_cost_model) Var(flag_simd_cost_model) Init(VECT_COST_MODEL_UNLIMITED)
2316 Specifies the vectorization cost model for code marked with a simd directive
2317
2318 Enum
2319 Name(vect_cost_model) Type(enum vect_cost_model) UnknownError(unknown vectorizer cost model %qs)
2320
2321 EnumValue
2322 Enum(vect_cost_model) String(unlimited) Value(VECT_COST_MODEL_UNLIMITED)
2323
2324 EnumValue
2325 Enum(vect_cost_model) String(dynamic) Value(VECT_COST_MODEL_DYNAMIC)
2326
2327 EnumValue
2328 Enum(vect_cost_model) String(cheap) Value(VECT_COST_MODEL_CHEAP)
2329
2330 fvect-cost-model
2331 Common RejectNegative Alias(fvect-cost-model=,dynamic)
2332 Enables the dynamic vectorizer cost model.  Preserved for backward compatibility.
2333
2334 fno-vect-cost-model
2335 Common RejectNegative Alias(fvect-cost-model=,unlimited)
2336 Enables the unlimited vectorizer cost model.  Preserved for backward compatibility.
2337
2338 ftree-vect-loop-version
2339 Common Ignore
2340 Does nothing. Preserved for backward compatibility.
2341
2342 ftree-scev-cprop
2343 Common Report Var(flag_tree_scev_cprop) Init(1) Optimization
2344 Enable copy propagation of scalar-evolution information.
2345
2346 ; -fverbose-asm causes extra commentary information to be produced in
2347 ; the generated assembly code (to make it more readable).  This option
2348 ; is generally only of use to those who actually need to read the
2349 ; generated assembly code (perhaps while debugging the compiler itself).
2350 ; -fno-verbose-asm, the default, causes the extra information
2351 ; to not be added and is useful when comparing two assembler files.
2352 fverbose-asm
2353 Common Report Var(flag_verbose_asm)
2354 Add extra commentary to assembler output
2355
2356 fvisibility=
2357 Common Joined RejectNegative Enum(symbol_visibility) Var(default_visibility) Init(VISIBILITY_DEFAULT)
2358 -fvisibility=[default|internal|hidden|protected]        Set the default symbol visibility
2359
2360 Enum
2361 Name(symbol_visibility) Type(enum symbol_visibility) UnknownError(unrecognized visibility value %qs)
2362
2363 EnumValue
2364 Enum(symbol_visibility) String(default) Value(VISIBILITY_DEFAULT)
2365
2366 EnumValue
2367 Enum(symbol_visibility) String(internal) Value(VISIBILITY_INTERNAL)
2368
2369 EnumValue
2370 Enum(symbol_visibility) String(hidden) Value(VISIBILITY_HIDDEN)
2371
2372 EnumValue
2373 Enum(symbol_visibility) String(protected) Value(VISIBILITY_PROTECTED)
2374
2375 fvtable-verify=
2376 Common Joined RejectNegative Enum(vtv_priority) Var(flag_vtable_verify) Init(VTV_NO_PRIORITY)
2377 Validate vtable pointers before using them.
2378
2379 Enum
2380 Name(vtv_priority) Type(enum vtv_priority) UnknownError(unknown vtable verify initialization priority %qs)
2381
2382 EnumValue
2383 Enum(vtv_priority) String(none) Value(VTV_NO_PRIORITY)
2384
2385 EnumValue
2386 Enum(vtv_priority) String(std) Value(VTV_STANDARD_PRIORITY)
2387
2388 EnumValue
2389 Enum(vtv_priority) String(preinit) Value(VTV_PREINIT_PRIORITY)
2390
2391 fvtv-counts
2392 Common Var(flag_vtv_counts)
2393 Output vtable verification counters.
2394
2395 fvtv-debug
2396 Common Var(flag_vtv_debug)
2397 Output vtable verification pointer sets information.
2398
2399 fvpt
2400 Common Report Var(flag_value_profile_transformations) Optimization
2401 Use expression value profiles in optimizations
2402
2403 fweb
2404 Common Report Var(flag_web) Init(2) Optimization
2405 Construct webs and split unrelated uses of single variable
2406
2407 ftree-builtin-call-dce
2408 Common Report Var(flag_tree_builtin_call_dce) Init(0) Optimization
2409 Enable conditional dead code elimination for builtin calls
2410
2411 fwhole-program
2412 Common Report Var(flag_whole_program) Init(0) Optimization
2413 Perform whole program optimizations
2414
2415 fwrapv
2416 Common Report Var(flag_wrapv) Optimization
2417 Assume signed arithmetic overflow wraps around
2418
2419 fzero-initialized-in-bss
2420 Common Report Var(flag_zero_initialized_in_bss) Init(1)
2421 Put zero initialized data in the bss section
2422
2423 g
2424 Common JoinedOrMissing
2425 Generate debug information in default format
2426
2427 gcoff
2428 Common JoinedOrMissing Negative(gdwarf)
2429 Generate debug information in COFF format
2430
2431 gdwarf
2432 Common JoinedOrMissing Negative(gdwarf-)
2433 Generate debug information in default version of DWARF format
2434
2435 gdwarf-
2436 Common Joined UInteger Var(dwarf_version) Init(4) Negative(gstabs)
2437 Generate debug information in DWARF v2 (or later) format
2438
2439 ggdb
2440 Common JoinedOrMissing
2441 Generate debug information in default extended format
2442
2443 gno-pubnames
2444 Common Negative(gpubnames) Var(debug_generate_pub_sections, 0) Init(-1)
2445 Don't generate DWARF pubnames and pubtypes sections.
2446
2447 gpubnames
2448 Common Negative(ggnu-pubnames) Var(debug_generate_pub_sections, 1)
2449 Generate DWARF pubnames and pubtypes sections.
2450
2451 ggnu-pubnames
2452 Common Negative(gno-pubnames) Var(debug_generate_pub_sections, 2)
2453 Generate DWARF pubnames and pubtypes sections with GNU extensions.
2454
2455 gno-record-gcc-switches
2456 Common RejectNegative Var(dwarf_record_gcc_switches,0) Init(1)
2457 Don't record gcc command line switches in DWARF DW_AT_producer.
2458
2459 grecord-gcc-switches
2460 Common RejectNegative Var(dwarf_record_gcc_switches,1)
2461 Record gcc command line switches in DWARF DW_AT_producer.
2462
2463 gno-split-dwarf
2464 Common Driver RejectNegative Var(dwarf_split_debug_info,0) Init(0)
2465 Don't generate debug information in separate .dwo files
2466
2467 gsplit-dwarf
2468 Common Driver RejectNegative Var(dwarf_split_debug_info,1)
2469 Generate debug information in separate .dwo files
2470
2471 gstabs
2472 Common JoinedOrMissing Negative(gstabs+)
2473 Generate debug information in STABS format
2474
2475 gstabs+
2476 Common JoinedOrMissing Negative(gvms)
2477 Generate debug information in extended STABS format
2478
2479 gno-strict-dwarf
2480 Common RejectNegative Var(dwarf_strict,0) Init(0)
2481 Emit DWARF additions beyond selected version
2482
2483 gstrict-dwarf
2484 Common Report RejectNegative Var(dwarf_strict,1)
2485 Don't emit DWARF additions beyond selected version
2486
2487 gtoggle
2488 Common Report Var(flag_gtoggle)
2489 Toggle debug information generation
2490
2491 gvms
2492 Common JoinedOrMissing Negative(gxcoff)
2493 Generate debug information in VMS format
2494
2495 gxcoff
2496 Common JoinedOrMissing Negative(gxcoff+)
2497 Generate debug information in XCOFF format
2498
2499 gxcoff+
2500 Common JoinedOrMissing Negative(gcoff)
2501 Generate debug information in extended XCOFF format
2502
2503 h
2504 Driver Joined Separate
2505
2506 iplugindir=
2507 Common Joined Var(plugindir_string) Init(0)
2508 -iplugindir=<dir>       Set <dir> to be the default plugin directory
2509
2510 imultiarch
2511 Common Joined Separate RejectDriver Var(imultiarch) Init(0)
2512 -imultiarch <dir>       Set <dir> to be the multiarch include subdirectory
2513
2514 l
2515 Driver Joined Separate
2516
2517 n
2518 Driver
2519
2520 no-canonical-prefixes
2521 Driver
2522
2523 nodefaultlibs
2524 Driver
2525
2526 nostartfiles
2527 Driver
2528
2529 nostdlib
2530 Driver
2531
2532 o
2533 Common Driver Joined Separate Var(asm_file_name) MissingArgError(missing filename after %qs)
2534 -o <file>       Place output into <file>
2535
2536 p
2537 Common Var(profile_flag)
2538 Enable function profiling
2539
2540 pass-exit-codes
2541 Driver Var(pass_exit_codes)
2542
2543 pedantic
2544 Common Alias(Wpedantic)
2545
2546 pedantic-errors
2547 Common Var(flag_pedantic_errors)
2548 Like -pedantic but issue them as errors
2549
2550 pg
2551 Driver
2552
2553 pipe
2554 Driver Var(use_pipes)
2555
2556 print-file-name=
2557 Driver JoinedOrMissing Var(print_file_name)
2558
2559 print-libgcc-file-name
2560 Driver
2561
2562 print-multi-directory
2563 Driver Var(print_multi_directory)
2564
2565 print-multi-lib
2566 Driver Var(print_multi_lib)
2567
2568 print-multi-os-directory
2569 Driver Var(print_multi_os_directory)
2570
2571 print-multiarch
2572 Driver Var(print_multiarch)
2573
2574 print-prog-name=
2575 Driver JoinedOrMissing Var(print_prog_name)
2576
2577 print-search-dirs
2578 Driver Var(print_search_dirs)
2579
2580 print-sysroot
2581 Driver Var(print_sysroot)
2582
2583 print-sysroot-headers-suffix
2584 Driver Var(print_sysroot_headers_suffix)
2585
2586 quiet
2587 Common Var(quiet_flag) RejectDriver
2588 Do not display functions compiled or elapsed time
2589
2590 r
2591 Driver
2592
2593 s
2594 Driver
2595
2596 save-temps
2597 Driver
2598
2599 save-temps=
2600 Driver Joined
2601
2602 t
2603 Driver
2604
2605 time
2606 Driver Var(report_times)
2607
2608 time=
2609 Driver JoinedOrMissing
2610
2611 u
2612 Driver Joined Separate
2613
2614 undef
2615 Driver
2616 ; C option, but driver must not handle as "-u ndef".
2617
2618 v
2619 Common Driver Var(verbose_flag)
2620 Enable verbose output
2621
2622 version
2623 Common Var(version_flag) RejectDriver
2624 Display the compiler's version
2625
2626 w
2627 Common Var(inhibit_warnings)
2628 Suppress warnings
2629
2630 wrapper
2631 Driver Separate Var(wrapper_string)
2632
2633 x
2634 Driver Joined Separate
2635
2636 shared
2637 Driver RejectNegative Negative(pie)
2638 Create a shared library
2639
2640 shared-libgcc
2641 Driver
2642
2643 specs
2644 Driver Separate Alias(specs=)
2645
2646 specs=
2647 Driver Joined
2648
2649 static
2650 Driver
2651
2652 static-libgcc
2653 Driver
2654
2655 static-libgfortran
2656 Driver
2657 ; Documented for Fortran, but always accepted by driver.
2658
2659 static-libstdc++
2660 Driver
2661
2662 static-libgo
2663 Driver
2664 ; Documented for Go, but always accepted by driver.
2665
2666 static-libasan
2667 Driver
2668
2669 static-libtsan
2670 Driver
2671
2672 static-liblsan
2673 Driver
2674
2675 static-libubsan
2676 Driver
2677
2678 symbolic
2679 Driver
2680
2681 pie
2682 Driver RejectNegative Negative(shared)
2683 Create a position independent executable
2684
2685 z
2686 Driver Joined Separate
2687
2688 ; This comment is to ensure we retain the blank line above.