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