gcc/common.opt

   1 ; Options for the language- and target-independent parts of the compiler.
   2
   3 ; Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012
   4 ; Free Software Foundation, Inc.
   5 ;
   6 ; This file is part of GCC.
   7 ;
   8 ; GCC is free software; you can redistribute it and/or modify it under
   9 ; the terms of the GNU General Public License as published by the Free
  10 ; Software Foundation; either version 3, or (at your option) any later
  11 ; version.
  12 ;
  13 ; GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  14 ; WARRANTY; without even the implied warranty of MERCHANTABILITY or
  15 ; FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  16 ; for more details.
  17 ;
  18 ; You should have received a copy of the GNU General Public License
  19 ; along with GCC; see the file COPYING3.  If not see
  20 ; <http://www.gnu.org/licenses/>.
  21
  22 ; See the GCC internals manual (options.texi) for a description of this file's format.
  23
  24 ; Please try to keep this file in ASCII collating order.
  25
  26 Variable
  27 int target_flags
  28
  29 Variable
  30 int optimize
  31
  32 Variable
  33 int optimize_size
  34
  35 Variable
  36 int optimize_debug
  37
  38 ; Not used directly to control optimizations, only to save -Ofast
  39 ; setting for "optimize" attributes.
  40 Variable
  41 int optimize_fast
  42
  43 ; True if this is the lto front end.  This is used to disable gimple
  44 ; generation and lowering passes that are normally run on the output
  45 ; of a front end.  These passes must be bypassed for lto since they
  46 ; have already been done before the gimple was written.
  47 Variable
  48 bool in_lto_p = false
  49
  50 ; 0 means straightforward implementation of complex divide acceptable.
  51 ; 1 means wide ranges of inputs must work for complex divide.
  52 ; 2 means C99-like requirements for complex multiply and divide.
  53 Variable
  54 int flag_complex_method = 1
  55
  56 ; Nonzero if subexpressions must be evaluated from left-to-right.
  57 Variable
  58 int flag_evaluation_order = 0
  59
  60 ; Language specific warning pass for unused results.
  61 Variable
  62 bool flag_warn_unused_result = false
  63
  64 Variable
  65 int *param_values
  66
  67 ; Nonzero if we should write GIMPLE bytecode for link-time optimization.
  68 Variable
  69 int flag_generate_lto
  70
  71 ; True to warn about any objects definitions whose size is larger
  72 ; than N bytes.  Also want about function definitions whose returned
  73 ; values are larger than N bytes, where N is 'larger_than_size'.
  74 Variable
  75 bool warn_larger_than
  76
  77 Variable
  78 HOST_WIDE_INT larger_than_size
  79
  80 ; True to warn about any function whose frame size is larger
  81 ; than N bytes.
  82 Variable
  83 bool warn_frame_larger_than
  84
  85 Variable
  86 HOST_WIDE_INT frame_larger_than_size
  87
  88 ; Nonzero means we should be saving declaration info into a .X file.
  89 Variable
  90 int flag_gen_aux_info = 0
  91
  92 ; Nonzero if we are compiling code for a shared library, zero for
  93 ; executable.
  94 Variable
  95 int flag_shlib
  96
  97 ; These two are really VEC(char_p,heap) *.
  98
  99 Variable
 100 void *flag_instrument_functions_exclude_functions
 101
 102 Variable
 103 void *flag_instrument_functions_exclude_files
 104
 105 ; Generic structs (e.g. templates not explicitly specialized)
 106 ; may not have a compilation unit associated with them, and so
 107 ; may need to be treated differently from ordinary structs.
 108 ;
 109 ; Structs only handled by reference (indirectly), will also usually
 110 ; not need as much debugging information.
 111
 112 Variable
 113 enum debug_struct_file debug_struct_ordinary[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
 114
 115 Variable
 116 enum debug_struct_file debug_struct_generic[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
 117
 118 ; True if we should exit after parsing options.
 119 Variable
 120 bool exit_after_options
 121
 122 ; Type(s) of debugging information we are producing (if any).  See
 123 ; flag-types.h for the definitions of the different possible types of
 124 ; debugging information.
 125 Variable
 126 enum debug_info_type write_symbols = NO_DEBUG
 127
 128 ; Level of debugging information we are producing.  See flag-types.h
 129 ; for the definitions of the different possible levels.
 130 Variable
 131 enum debug_info_levels debug_info_level = DINFO_LEVEL_NONE
 132
 133 ; Nonzero means use GNU-only extensions in the generated symbolic
 134 ; debugging information.  Currently, this only has an effect when
 135 ; write_symbols is set to DBX_DEBUG, XCOFF_DEBUG, or DWARF_DEBUG.
 136 Variable
 137 bool use_gnu_debug_info_extensions
 138
 139 ; Original value of maximum field alignment in bytes, specified via
 140 ; -fpack-struct=<value>.
 141 Variable
 142 unsigned int initial_max_fld_align = TARGET_DEFAULT_PACK_STRUCT
 143
 144 ; Type of stack check.
 145 Variable
 146 enum stack_check_type flag_stack_check = NO_STACK_CHECK
 147
 148 ; True if stack usage information needs to be computed.
 149 Variable
 150 bool flag_stack_usage_info = false
 151
 152 ; -dA causes debug commentary information to be produced in
 153 ; the generated assembly code (to make it more readable).  This option
 154 ; is generally only of use to those who actually need to read the
 155 ; generated assembly code (perhaps while debugging the compiler itself).
 156 ; Currently, this switch is only used by dwarf2out.c; however, it is intended
 157 ; to be a catchall for printing debug information in the assembler file.
 158 Variable
 159 int flag_debug_asm
 160
 161 ; -dP causes the rtl to be emitted as a comment in assembly.
 162 Variable
 163 int flag_dump_rtl_in_asm
 164
 165 ; Whether -da was passed (used only in handle_common_deferred_options).
 166 Variable
 167 bool flag_dump_all_passed
 168
 169 ; Other flags saying which kinds of debugging dump have been requested.
 170
 171 Variable
 172 int rtl_dump_and_exit
 173
 174 Variable
 175 int flag_print_asm_name
 176
 177 Variable
 178 enum graph_dump_types graph_dump_format = no_graph
 179
 180 ; Name of top-level original source file (what was input to cpp).
 181 ; This comes from the #-command at the beginning of the actual input.
 182 ; If there isn't any there, then this is the cc1 input file name.
 183 Variable
 184 const char *main_input_filename
 185
 186 ; Pointer to base name in main_input_filename, with directories and a
 187 ; single final extension removed, and the length of this base
 188 ; name.
 189
 190 Variable
 191 const char *main_input_basename
 192
 193 Variable
 194 int main_input_baselength
 195
 196 ; Which options have been printed by --help.
 197 Variable
 198 char *help_printed
 199
 200 ; Which enums have been printed by --help.  0 = not printed, no
 201 ; relevant options seen, 1 = relevant option seen, not yet printed, 2
 202 ; = printed.
 203 Variable
 204 char *help_enum_printed
 205
 206 ; The number of columns for --help output.
 207 Variable
 208 unsigned int help_columns
 209
 210 ; Whether this options structure has been through finish_options
 211 Variable
 212 bool flag_opts_finished
 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 Warray-bounds
 513 Common Var(warn_array_bounds) Warning
 514 Warn if an array is accessed out of bounds
 515
 516 Wattributes
 517 Common Var(warn_attributes) Init(1) Warning
 518 Warn about inappropriate attribute usage
 519
 520 Wcast-align
 521 Common Var(warn_cast_align) Warning
 522 Warn about pointer casts which increase alignment
 523
 524 Wcpp
 525 Common Var(warn_cpp) Init(1) Warning
 526 Warn when a #warning directive is encountered
 527
 528 Wdeprecated-declarations
 529 Common Var(warn_deprecated_decl) Init(1) Warning
 530 Warn about uses of __attribute__((deprecated)) declarations
 531
 532 Wdisabled-optimization
 533 Common Var(warn_disabled_optimization) Warning
 534 Warn when an optimization pass is disabled
 535
 536 Werror
 537 Common Var(warnings_are_errors)
 538 Treat all warnings as errors
 539
 540 Werror=
 541 Common Joined
 542 Treat specified warning as error
 543
 544 Wextra
 545 Common Var(extra_warnings) Warning
 546 Print extra (possibly unwanted) warnings
 547
 548 Wfatal-errors
 549 Common Var(flag_fatal_errors)
 550 Exit on the first error occurred
 551
 552 Wframe-larger-than=
 553 Common RejectNegative Joined UInteger
 554 -Wframe-larger-than=<number>    Warn if a function's stack frame requires more than <number> bytes
 555
 556 Wfree-nonheap-object
 557 Common Var(warn_free_nonheap_object) Init(1) Warning
 558 Warn when attempting to free a non-heap object
 559
 560 Winline
 561 Common Var(warn_inline) Warning
 562 Warn when an inlined function cannot be inlined
 563
 564 Winvalid-memory-model
 565 Common Var(warn_invalid_memory_model) Init(1) Warning
 566 Warn when an atomic memory model parameter is known to be outside the valid range.
 567
 568 Wlarger-than-
 569 Common RejectNegative Joined Warning Undocumented Alias(Wlarger-than=)
 570
 571 Wlarger-than=
 572 Common RejectNegative Joined UInteger Warning
 573 -Wlarger-than=<number>  Warn if an object is larger than <number> bytes
 574
 575 Wunsafe-loop-optimizations
 576 Common Var(warn_unsafe_loop_optimizations) Warning
 577 Warn if the loop cannot be optimized due to nontrivial assumptions.
 578
 579 Wmissing-noreturn
 580 Common Alias(Wsuggest-attribute=noreturn)
 581
 582 Woverflow
 583 Common Var(warn_overflow) Init(1) Warning
 584 Warn about overflow in arithmetic expressions
 585
 586 Wpacked
 587 Common Var(warn_packed) Warning
 588 Warn when the packed attribute has no effect on struct layout
 589
 590 Wpadded
 591 Common Var(warn_padded) Warning
 592 Warn when padding is required to align structure members
 593
 594 Wpedantic
 595 Common Var(pedantic) Warning
 596 Issue warnings needed for strict compliance to the standard
 597
 598 Wshadow
 599 Common Var(warn_shadow) Warning
 600 Warn when one local variable shadows another
 601
 602 Wstack-protector
 603 Common Var(warn_stack_protect) Warning
 604 Warn when not issuing stack smashing protection for some reason
 605
 606 Wstack-usage=
 607 Common Joined RejectNegative UInteger Var(warn_stack_usage) Init(-1) Warning
 608 Warn if stack usage might be larger than specified amount
 609
 610 Wstrict-aliasing
 611 Common Warning
 612 Warn about code which might break strict aliasing rules
 613
 614 Wstrict-aliasing=
 615 Common Joined RejectNegative UInteger Var(warn_strict_aliasing) Warning
 616 Warn about code which might break strict aliasing rules
 617
 618 Wstrict-overflow
 619 Common Warning
 620 Warn about optimizations that assume that signed overflow is undefined
 621
 622 Wstrict-overflow=
 623 Common Joined RejectNegative UInteger Var(warn_strict_overflow) Warning
 624 Warn about optimizations that assume that signed overflow is undefined
 625
 626 Wsuggest-attribute=const
 627 Common Var(warn_suggest_attribute_const) Warning
 628 Warn about functions which might be candidates for __attribute__((const))
 629
 630 Wsuggest-attribute=pure
 631 Common Var(warn_suggest_attribute_pure) Warning
 632 Warn about functions which might be candidates for __attribute__((pure))
 633
 634 Wsuggest-attribute=noreturn
 635 Common Var(warn_suggest_attribute_noreturn) Warning
 636 Warn about functions which might be candidates for __attribute__((noreturn))
 637
 638 Wsystem-headers
 639 Common Var(warn_system_headers) Warning
 640 Do not suppress warnings from system headers
 641
 642 Wtrampolines
 643 Common Var(warn_trampolines) Warning
 644 Warn whenever a trampoline is generated
 645
 646 Wtype-limits
 647 Common Var(warn_type_limits) Warning EnabledBy(Wextra)
 648 Warn if a comparison is always true or always false due to the limited range of the data type
 649
 650 Wuninitialized
 651 Common Var(warn_uninitialized) Warning EnabledBy(Wextra)
 652 Warn about uninitialized automatic variables
 653
 654 Wmaybe-uninitialized
 655 Common Var(warn_maybe_uninitialized) Warning EnabledBy(Wuninitialized)
 656 Warn about maybe uninitialized automatic variables
 657
 658 Wunreachable-code
 659 Common Ignore
 660 Does nothing. Preserved for backward compatibility.
 661
 662 Wunused
 663 Common Var(warn_unused) Init(0) Warning
 664 Enable all -Wunused- warnings
 665
 666 Wunused-but-set-parameter
 667 Common Var(warn_unused_but_set_parameter) Warning EnabledBy(Wunused && Wextra)
 668 Warn when a function parameter is only set, otherwise unused
 669
 670 Wunused-but-set-variable
 671 Common Var(warn_unused_but_set_variable) Warning EnabledBy(Wunused)
 672 Warn when a variable is only set, otherwise unused
 673
 674 Wunused-function
 675 Common Var(warn_unused_function) Warning EnabledBy(Wunused)
 676 Warn when a function is unused
 677
 678 Wunused-label
 679 Common Var(warn_unused_label) Warning EnabledBy(Wunused)
 680 Warn when a label is unused
 681
 682 Wunused-parameter
 683 Common Var(warn_unused_parameter) Warning EnabledBy(Wunused && Wextra)
 684 Warn when a function parameter is unused
 685
 686 Wunused-value
 687 Common Var(warn_unused_value) Warning EnabledBy(Wunused)
 688 Warn when an expression value is unused
 689
 690 Wunused-variable
 691 Common Var(warn_unused_variable) Warning EnabledBy(Wunused)
 692 Warn when a variable is unused
 693
 694 Wcoverage-mismatch
 695 Common Var(warn_coverage_mismatch) Init(1) Warning
 696 Warn in case profiles in -fprofile-use do not match
 697
 698 Wvector-operation-performance
 699 Common Var(warn_vector_operation_performance) Warning
 700 Warn when a vector operation is compiled outside the SIMD
 701
 702 Xassembler
 703 Driver Separate
 704
 705 Xlinker
 706 Driver Separate
 707
 708 Xpreprocessor
 709 Driver Separate
 710
 711 Z
 712 Driver
 713
 714 aux-info
 715 Common Separate Var(aux_info_file_name)
 716 -aux-info <file>        Emit declaration information into <file>
 717
 718 aux-info=
 719 Common Joined Alias(aux-info)
 720
 721 auxbase
 722 Common Separate RejectDriver Var(aux_base_name)
 723
 724 auxbase-strip
 725 Common Separate RejectDriver
 726
 727 coverage
 728 Driver
 729
 730 c
 731 Driver
 732
 733 d
 734 Common Joined
 735 -d<letters>     Enable dumps from specific passes of the compiler
 736
 737 dumpbase
 738 Common Separate Var(dump_base_name)
 739 -dumpbase <file>        Set the file basename to be used for dumps
 740
 741 dumpdir
 742 Common Separate Var(dump_dir_name)
 743 -dumpdir <dir>  Set the directory name to be used for dumps
 744
 745 dumpmachine
 746 Driver
 747
 748 dumpspecs
 749 Driver
 750
 751 dumpversion
 752 Driver
 753
 754 e
 755 Driver Joined Separate
 756
 757 ; This option has historically been passed down to the linker by an
 758 ; accident of a %{e*} spec, so ensure it continues to be passed down
 759 ; as a single option.  The supported option for this purpose is
 760 ; -rdynamic.  See PR 47390.
 761 export-dynamic
 762 Driver Undocumented
 763
 764 ; The version of the C++ ABI in use.  The following values are allowed:
 765 ;
 766 ; 0: The version of the ABI believed most conformant with the C++ ABI
 767 ;    specification.  This ABI may change as bugs are discovered and fixed.
 768 ;    Therefore, 0 will not necessarily indicate the same ABI in different
 769 ;    versions of G++.
 770 ;
 771 ; 1: The version of the ABI first used in G++ 3.2.
 772 ;
 773 ; 2: The version of the ABI first used in G++ 3.4 (and current default).
 774 ;
 775 ; 3: The version of the ABI that fixes the missing underscore
 776 ;    in template non-type arguments of pointer type.
 777 ;
 778 ; 4: The version of the ABI that introduces unambiguous mangling of
 779 ;    vector types.  First selectable in G++ 4.5.
 780 ;
 781 ; 5: The version of the ABI that ignores attribute const/noreturn
 782 ;    in function pointer mangling, and corrects mangling of decltype and
 783 ;    function parameters used in other parameters and the return type.
 784 ;    First selectable in G++ 4.6.
 785 ;
 786 ; 6: The version of the ABI that doesn't promote scoped enums to int and
 787 ;    changes the mangling of template argument packs, const/static_cast,
 788 ;    prefix ++ and --, and a class scope function used as a template
 789 ;    argument.
 790 ;    First selectable in G++ 4.7.
 791 ;
 792 ; 7: The version of the ABI that treats nullptr_t as a builtin type.
 793 ;    First selectable in G++ 4.8.
 794 ; Additional positive integers will be assigned as new versions of
 795 ; the ABI become the default version of the ABI.
 796 fabi-version=
 797 Common Joined RejectNegative UInteger Var(flag_abi_version) Init(2)
 798
 799 falign-functions
 800 Common Report Var(align_functions,0) Optimization UInteger
 801 Align the start of functions
 802
 803 falign-functions=
 804 Common RejectNegative Joined UInteger Var(align_functions)
 805
 806 falign-jumps
 807 Common Report Var(align_jumps,0) Optimization UInteger
 808 Align labels which are only reached by jumping
 809
 810 falign-jumps=
 811 Common RejectNegative Joined UInteger Var(align_jumps)
 812
 813 falign-labels
 814 Common Report Var(align_labels,0) Optimization UInteger
 815 Align all labels
 816
 817 falign-labels=
 818 Common RejectNegative Joined UInteger Var(align_labels)
 819
 820 falign-loops
 821 Common Report Var(align_loops,0) Optimization UInteger
 822 Align the start of loops
 823
 824 falign-loops=
 825 Common RejectNegative Joined UInteger Var(align_loops)
 826
 827 fargument-alias
 828 Common Ignore
 829 Does nothing. Preserved for backward compatibility.
 830
 831 fargument-noalias
 832 Common Ignore
 833 Does nothing. Preserved for backward compatibility.
 834
 835 fargument-noalias-global
 836 Common Ignore
 837 Does nothing. Preserved for backward compatibility.
 838
 839 fargument-noalias-anything
 840 Common Ignore
 841 Does nothing. Preserved for backward compatibility.
 842
 843 faddress-sanitizer
 844 Common Report Var(flag_asan)
 845 Enable AddressSanitizer, a memory error detector
 846
 847 fasynchronous-unwind-tables
 848 Common Report Var(flag_asynchronous_unwind_tables) Optimization
 849 Generate unwind tables that are exact at each instruction boundary
 850
 851 fauto-inc-dec
 852 Common Report Var(flag_auto_inc_dec) Init(1)
 853 Generate auto-inc/dec instructions
 854
 855 ; -fcheck-bounds causes gcc to generate array bounds checks.
 856 ; For C, C++ and ObjC: defaults off.
 857 ; For Java: defaults to on.
 858 ; For Fortran: defaults to off.
 859 fbounds-check
 860 Common Report Var(flag_bounds_check)
 861 Generate code to check bounds before indexing arrays
 862
 863 fbranch-count-reg
 864 Common Report Var(flag_branch_on_count_reg) Init(1) Optimization
 865 Replace add, compare, branch with branch on count register
 866
 867 fbranch-probabilities
 868 Common Report Var(flag_branch_probabilities) Optimization
 869 Use profiling information for branch probabilities
 870
 871 fbranch-target-load-optimize
 872 Common Report Var(flag_branch_target_load_optimize) Optimization
 873 Perform branch target load optimization before prologue / epilogue threading
 874
 875 fbranch-target-load-optimize2
 876 Common Report Var(flag_branch_target_load_optimize2) Optimization
 877 Perform branch target load optimization after prologue / epilogue threading
 878
 879 fbtr-bb-exclusive
 880 Common Report Var(flag_btr_bb_exclusive) Optimization
 881 Restrict target load migration not to re-use registers in any basic block
 882
 883 fcall-saved-
 884 Common Joined RejectNegative Var(common_deferred_options) Defer
 885 -fcall-saved-<register> Mark <register> as being preserved across functions
 886
 887 fcall-used-
 888 Common Joined RejectNegative Var(common_deferred_options) Defer
 889 -fcall-used-<register>  Mark <register> as being corrupted by function calls
 890
 891 ; Nonzero for -fcaller-saves: allocate values in regs that need to
 892 ; be saved across function calls, if that produces overall better code.
 893 ; Optional now, so people can test it.
 894 fcaller-saves
 895 Common Report Var(flag_caller_saves) Optimization
 896 Save registers around function calls
 897
 898 fcheck-data-deps
 899 Common Report Var(flag_check_data_deps)
 900 Compare the results of several data dependence analyzers.
 901
 902 fcombine-stack-adjustments
 903 Common Report Var(flag_combine_stack_adjustments) Optimization
 904 Looks for opportunities to reduce stack adjustments and stack references.
 905
 906 fcommon
 907 Common Report Var(flag_no_common,0) Optimization
 908 Do not put uninitialized globals in the common section
 909
 910 fcompare-debug
 911 Driver
 912 ; Converted by the driver to -fcompare-debug= options.
 913
 914 fcompare-debug=
 915 Common Driver JoinedOrMissing RejectNegative Var(flag_compare_debug_opt)
 916 -fcompare-debug[=<opts>]        Compile with and without e.g. -gtoggle, and compare the final-insns dump
 917
 918 fcompare-debug-second
 919 Common Driver RejectNegative Var(flag_compare_debug)
 920 Run only the second compilation of -fcompare-debug
 921
 922 fcompare-elim
 923 Common Report Var(flag_compare_elim_after_reload) Optimization
 924 Perform comparison elimination after register allocation has finished
 925
 926 fconserve-stack
 927 Common Var(flag_conserve_stack) Optimization
 928 Do not perform optimizations increasing noticeably stack usage
 929
 930 fcprop-registers
 931 Common Report Var(flag_cprop_registers) Optimization
 932 Perform a register copy-propagation optimization pass
 933
 934 fcrossjumping
 935 Common Report Var(flag_crossjumping) Optimization
 936 Perform cross-jumping optimization
 937
 938 fcse-follow-jumps
 939 Common Report Var(flag_cse_follow_jumps) Optimization
 940 When running CSE, follow jumps to their targets
 941
 942 fcse-skip-blocks
 943 Common Ignore
 944 Does nothing.  Preserved for backward compatibility.
 945
 946 fcx-limited-range
 947 Common Report Var(flag_cx_limited_range) Optimization SetByCombined
 948 Omit range reduction step when performing complex division
 949
 950 fcx-fortran-rules
 951 Common Report Var(flag_cx_fortran_rules) Optimization
 952 Complex multiplication and division follow Fortran rules
 953
 954 fdata-sections
 955 Common Report Var(flag_data_sections) Optimization
 956 Place data items into their own section
 957
 958 fdbg-cnt-list
 959 Common Report Var(common_deferred_options) Defer
 960 List all available debugging counters with their limits and counts.
 961
 962 fdbg-cnt=
 963 Common RejectNegative Joined Var(common_deferred_options) Defer
 964 -fdbg-cnt=<counter>:<limit>[,<counter>:<limit>,...]     Set the debug counter limit.
 965
 966 fdebug-prefix-map=
 967 Common Joined RejectNegative Var(common_deferred_options) Defer
 968 Map one directory name to another in debug information
 969
 970 fdebug-types-section
 971 Common Report Var(flag_debug_types_section) Init(0)
 972 Output .debug_types section when using DWARF v4 debuginfo.
 973
 974 ; Nonzero for -fdefer-pop: don't pop args after each function call
 975 ; instead save them up to pop many calls' args with one insns.
 976 fdefer-pop
 977 Common Report Var(flag_defer_pop) Optimization
 978 Defer popping functions args from stack until later
 979
 980 fdelayed-branch
 981 Common Report Var(flag_delayed_branch) Optimization
 982 Attempt to fill delay slots of branch instructions
 983
 984 fdelete-dead-exceptions
 985 Common Report Var(flag_delete_dead_exceptions) Init(0)
 986 Delete dead instructions that may throw exceptions
 987
 988 fdelete-null-pointer-checks
 989 Common Report Var(flag_delete_null_pointer_checks) Init(1) Optimization
 990 Delete useless null pointer checks
 991
 992 fdevirtualize
 993 Common Report Var(flag_devirtualize) Optimization
 994 Try to convert virtual calls to direct ones.
 995
 996 fdiagnostics-show-location=
 997 Common Joined RejectNegative Enum(diagnostic_prefixing_rule)
 998 -fdiagnostics-show-location=[once|every-line]   How often to emit source location at the beginning of line-wrapped diagnostics
 999
1000 ; Required for these enum values.
1001 SourceInclude
1002 pretty-print.h
1003
1004 Enum
1005 Name(diagnostic_prefixing_rule) Type(int)
1006
1007 EnumValue
1008 Enum(diagnostic_prefixing_rule) String(once) Value(DIAGNOSTICS_SHOW_PREFIX_ONCE)
1009
1010 EnumValue
1011 Enum(diagnostic_prefixing_rule) String(every-line) Value(DIAGNOSTICS_SHOW_PREFIX_EVERY_LINE)
1012
1013 fdiagnostics-show-caret
1014 Common Var(flag_diagnostics_show_caret) Init(1)
1015 Show the source line with a caret indicating the column
1016
1017 fdiagnostics-show-option
1018 Common Var(flag_diagnostics_show_option) Init(1)
1019 Amend appropriate diagnostic messages with the command line option that controls them
1020
1021 fdisable-
1022 Common Joined RejectNegative Var(common_deferred_options) Defer
1023 -fdisable-[tree|rtl|ipa]-<pass>=range1+range2 disables an optimization pass
1024
1025 fenable-
1026 Common Joined RejectNegative Var(common_deferred_options) Defer
1027 -fenable-[tree|rtl|ipa]-<pass>=range1+range2 enables an optimization pass
1028
1029 fdump-
1030 Common Joined RejectNegative Var(common_deferred_options) Defer
1031 -fdump-<type>   Dump various compiler internals to a file
1032
1033 fdump-final-insns
1034 Driver RejectNegative
1035
1036 fdump-final-insns=
1037 Common RejectNegative Joined Var(flag_dump_final_insns)
1038 -fdump-final-insns=filename     Dump to filename the insns at the end of translation
1039
1040 fdump-go-spec=
1041 Common RejectNegative Joined Var(flag_dump_go_spec)
1042 -fdump-go-spec=filename Write all declarations to file as Go code
1043
1044 fdump-noaddr
1045 Common Report Var(flag_dump_noaddr)
1046 Suppress output of addresses in debugging dumps
1047
1048 fdump-passes
1049 Common Var(flag_dump_passes) Init(0)
1050 Dump optimization passes
1051
1052 fdump-unnumbered
1053 Common Report Var(flag_dump_unnumbered)
1054 Suppress output of instruction numbers, line number notes and addresses in debugging dumps
1055
1056 fdump-unnumbered-links
1057 Common Report Var(flag_dump_unnumbered_links)
1058 Suppress output of previous and next insn numbers in debugging dumps
1059
1060 fdwarf2-cfi-asm
1061 Common Report Var(flag_dwarf2_cfi_asm) Init(HAVE_GAS_CFI_DIRECTIVE)
1062 Enable CFI tables via GAS assembler directives.
1063
1064 fearly-inlining
1065 Common Report Var(flag_early_inlining) Init(1) Optimization
1066 Perform early inlining
1067
1068 feliminate-dwarf2-dups
1069 Common Report Var(flag_eliminate_dwarf2_dups)
1070 Perform DWARF2 duplicate elimination
1071
1072 fipa-sra
1073 Common Report Var(flag_ipa_sra) Init(0) Optimization
1074 Perform interprocedural reduction of aggregates
1075
1076 feliminate-unused-debug-symbols
1077 Common Report Var(flag_debug_only_used_symbols)
1078 Perform unused type elimination in debug info
1079
1080 feliminate-unused-debug-types
1081 Common Report Var(flag_eliminate_unused_debug_types) Init(1)
1082 Perform unused type elimination in debug info
1083
1084 femit-class-debug-always
1085 Common Report Var(flag_emit_class_debug_always) Init(0)
1086 Do not suppress C++ class debug information.
1087
1088 fexceptions
1089 Common Report Var(flag_exceptions) Optimization
1090 Enable exception handling
1091
1092 fexpensive-optimizations
1093 Common Report Var(flag_expensive_optimizations) Optimization
1094 Perform a number of minor, expensive optimizations
1095
1096 fexcess-precision=
1097 Common Joined RejectNegative Enum(excess_precision) Var(flag_excess_precision_cmdline) Init(EXCESS_PRECISION_DEFAULT)
1098 -fexcess-precision=[fast|standard]      Specify handling of excess floating-point precision
1099
1100 Enum
1101 Name(excess_precision) Type(enum excess_precision) UnknownError(unknown excess precision style %qs)
1102
1103 EnumValue
1104 Enum(excess_precision) String(fast) Value(EXCESS_PRECISION_FAST)
1105
1106 EnumValue
1107 Enum(excess_precision) String(standard) Value(EXCESS_PRECISION_STANDARD)
1108
1109 ffast-math
1110 Common
1111
1112 ffat-lto-objects
1113 Common Var(flag_fat_lto_objects) Init(1)
1114 Output lto objects containing both the intermediate language and binary output.
1115
1116 ffinite-math-only
1117 Common Report Var(flag_finite_math_only) Optimization SetByCombined
1118 Assume no NaNs or infinities are generated
1119
1120 ffixed-
1121 Common Joined RejectNegative Var(common_deferred_options) Defer
1122 -ffixed-<register>      Mark <register> as being unavailable to the compiler
1123
1124 ffloat-store
1125 Common Report Var(flag_float_store) Optimization
1126 Don't allocate floats and doubles in extended-precision registers
1127
1128 fforce-addr
1129 Common Ignore
1130 Does nothing.  Preserved for backward compatibility.
1131
1132 fforward-propagate
1133 Common Report Var(flag_forward_propagate) Optimization
1134 Perform a forward propagation pass on RTL
1135
1136 ffp-contract=
1137 Common Joined RejectNegative Enum(fp_contract_mode) Var(flag_fp_contract_mode) Init(FP_CONTRACT_FAST)
1138 -ffp-contract=[off|on|fast] Perform floating-point expression contraction.
1139
1140 Enum
1141 Name(fp_contract_mode) Type(enum fp_contract_mode) UnknownError(unknown floating point contraction style %qs)
1142
1143 EnumValue
1144 Enum(fp_contract_mode) String(off) Value(FP_CONTRACT_OFF)
1145
1146 ; Not implemented, fall back to conservative FP_CONTRACT_OFF.
1147 EnumValue
1148 Enum(fp_contract_mode) String(on) Value(FP_CONTRACT_OFF)
1149
1150 EnumValue
1151 Enum(fp_contract_mode) String(fast) Value(FP_CONTRACT_FAST)
1152
1153 ; Nonzero means don't put addresses of constant functions in registers.
1154 ; Used for compiling the Unix kernel, where strange substitutions are
1155 ; done on the assembly output.
1156 ffunction-cse
1157 Common Report Var(flag_no_function_cse,0)
1158 Allow function addresses to be held in registers
1159
1160 ffunction-sections
1161 Common Report Var(flag_function_sections)
1162 Place each function into its own section
1163
1164 fgcse
1165 Common Report Var(flag_gcse) Optimization
1166 Perform global common subexpression elimination
1167
1168 fgcse-lm
1169 Common Report Var(flag_gcse_lm) Init(1) Optimization
1170 Perform enhanced load motion during global common subexpression elimination
1171
1172 fgcse-sm
1173 Common Report Var(flag_gcse_sm) Init(0) Optimization
1174 Perform store motion after global common subexpression elimination
1175
1176 fgcse-las
1177 Common Report Var(flag_gcse_las) Init(0) Optimization
1178 Perform redundant load after store elimination in global common subexpression
1179 elimination
1180
1181 fgcse-after-reload
1182 Common Report Var(flag_gcse_after_reload) Optimization
1183 Perform global common subexpression elimination after register allocation
1184 has finished
1185
1186 ; This option is not documented yet as its semantics will change.
1187 fgraphite
1188 Common Report Var(flag_graphite)
1189 Enable in and out of Graphite representation
1190
1191 fgraphite-identity
1192 Common Report Var(flag_graphite_identity) Optimization
1193 Enable Graphite Identity transformation
1194
1195 fhoist-adjacent-loads
1196 Common Report Var(flag_hoist_adjacent_loads) Optimization
1197 Enable hoisting adjacent loads to encourage generating conditional move
1198 instructions
1199
1200 floop-parallelize-all
1201 Common Report Var(flag_loop_parallelize_all) Optimization
1202 Mark all loops as parallel
1203
1204 floop-strip-mine
1205 Common Report Var(flag_loop_strip_mine) Optimization
1206 Enable Loop Strip Mining transformation
1207
1208 floop-interchange
1209 Common Report Var(flag_loop_interchange) Optimization
1210 Enable Loop Interchange transformation
1211
1212 floop-block
1213 Common Report Var(flag_loop_block) Optimization
1214 Enable Loop Blocking transformation
1215
1216 fgnu-tm
1217 Common Report Var(flag_tm)
1218 Enable support for GNU transactional memory
1219
1220 floop-flatten
1221 Common Ignore
1222 Does nothing. Preserved for backward compatibility.
1223
1224 floop-nest-optimize
1225 Common Report Var(flag_loop_optimize_isl) Optimization
1226 Enable the ISL based loop nest optimizer
1227
1228 fstrict-volatile-bitfields
1229 Common Report Var(flag_strict_volatile_bitfields) Init(-1)
1230 Force bitfield accesses to match their type width
1231
1232 fguess-branch-probability
1233 Common Report Var(flag_guess_branch_prob) Optimization
1234 Enable guessing of branch probabilities
1235
1236 ; Nonzero means ignore `#ident' directives.  0 means handle them.
1237 ; Generate position-independent code for executables if possible
1238 ; On SVR4 targets, it also controls whether or not to emit a
1239 ; string identifying the compiler.
1240 fident
1241 Common Report Var(flag_no_ident,0)
1242 Process #ident directives
1243
1244 fif-conversion
1245 Common Report Var(flag_if_conversion) Optimization
1246 Perform conversion of conditional jumps to branchless equivalents
1247
1248 fif-conversion2
1249 Common Report Var(flag_if_conversion2) Optimization
1250 Perform conversion of conditional jumps to conditional execution
1251
1252 fstack-reuse=
1253 Common Joined RejectNegative Enum(stack_reuse_level) Var(flag_stack_reuse) Init(SR_ALL)
1254 -fstack-reuse=[all|named_vars|none] Set stack reuse level for local variables.
1255
1256 Enum
1257 Name(stack_reuse_level) Type(enum stack_reuse_level) UnknownError(unknown Stack Reuse Level %qs)
1258
1259 EnumValue
1260 Enum(stack_reuse_level) String(all) Value(SR_ALL)
1261
1262 EnumValue
1263 Enum(stack_reuse_level) String(named_vars) Value(SR_NAMED_VARS)
1264
1265 EnumValue
1266 Enum(stack_reuse_level) String(none) Value(SR_NONE)
1267
1268 ftree-loop-if-convert
1269 Common Report Var(flag_tree_loop_if_convert) Init(-1) Optimization
1270 Convert conditional jumps in innermost loops to branchless equivalents
1271
1272 ftree-loop-if-convert-stores
1273 Common Report Var(flag_tree_loop_if_convert_stores) Optimization
1274 Also if-convert conditional jumps containing memory writes
1275
1276 ; -finhibit-size-directive inhibits output of .size for ELF.
1277 ; This is used only for compiling crtstuff.c,
1278 ; and it may be extended to other effects
1279 ; needed for crtstuff.c on other systems.
1280 finhibit-size-directive
1281 Common Report Var(flag_inhibit_size_directive)
1282 Do not generate .size directives
1283
1284 findirect-inlining
1285 Common Report Var(flag_indirect_inlining)
1286 Perform indirect inlining
1287
1288 ; General flag to enable inlining.  Specifying -fno-inline will disable
1289 ; all inlining apart from always-inline functions.
1290 finline
1291 Common Report Var(flag_no_inline,0) Init(0) Optimization
1292 Enable inlining of function declared \"inline\", disabling disables all inlining
1293
1294 finline-small-functions
1295 Common Report Var(flag_inline_small_functions) Optimization
1296 Integrate functions into their callers when code size is known not to grow
1297
1298 finline-functions
1299 Common Report Var(flag_inline_functions) Optimization
1300 Integrate functions not declared \"inline\" into their callers when profitable
1301
1302 finline-functions-called-once
1303 Common Report Var(flag_inline_functions_called_once) Optimization
1304 Integrate functions only required by their single caller
1305
1306 finline-limit-
1307 Common RejectNegative Joined Alias(finline-limit=)
1308
1309 finline-limit=
1310 Common RejectNegative Joined UInteger
1311 -finline-limit=<number> Limit the size of inlined functions to <number>
1312
1313 finline-atomics
1314 Common Report Var(flag_inline_atomics) Init(1) Optimization
1315 Inline __atomic operations when a lock free instruction sequence is available.
1316
1317 finstrument-functions
1318 Common Report Var(flag_instrument_function_entry_exit)
1319 Instrument function entry and exit with profiling calls
1320
1321 finstrument-functions-exclude-function-list=
1322 Common RejectNegative Joined
1323 -finstrument-functions-exclude-function-list=name,...  Do not instrument listed functions
1324
1325 finstrument-functions-exclude-file-list=
1326 Common RejectNegative Joined
1327 -finstrument-functions-exclude-file-list=filename,...  Do not instrument functions listed in files
1328
1329 fipa-cp
1330 Common Report Var(flag_ipa_cp) Optimization
1331 Perform Interprocedural constant propagation
1332
1333 fipa-cp-clone
1334 Common Report Var(flag_ipa_cp_clone) Optimization
1335 Perform cloning to make Interprocedural constant propagation stronger
1336
1337 fipa-profile
1338 Common Report Var(flag_ipa_profile) Init(0) Optimization
1339 Perform interprocedural profile propagation
1340
1341 fipa-pta
1342 Common Report Var(flag_ipa_pta) Init(0) Optimization
1343 Perform interprocedural points-to analysis
1344
1345 fipa-pure-const
1346 Common Report Var(flag_ipa_pure_const) Init(0) Optimization
1347 Discover pure and const functions
1348
1349 fipa-reference
1350 Common Report Var(flag_ipa_reference) Init(0) Optimization
1351 Discover readonly and non addressable static variables
1352
1353 fipa-matrix-reorg
1354 Common Ignore
1355 Does nothing. Preserved for backward compatibility.
1356
1357 fipa-struct-reorg
1358 Common Ignore
1359 Does nothing. Preserved for backward compatibility.
1360
1361 fira-algorithm=
1362 Common Joined RejectNegative Enum(ira_algorithm) Var(flag_ira_algorithm) Init(IRA_ALGORITHM_CB)
1363 -fira-algorithm=[CB|priority] Set the used IRA algorithm
1364
1365 Enum
1366 Name(ira_algorithm) Type(enum ira_algorithm) UnknownError(unknown IRA algorithm %qs)
1367
1368 EnumValue
1369 Enum(ira_algorithm) String(CB) Value(IRA_ALGORITHM_CB)
1370
1371 EnumValue
1372 Enum(ira_algorithm) String(priority) Value(IRA_ALGORITHM_PRIORITY)
1373
1374 fira-region=
1375 Common Joined RejectNegative Enum(ira_region) Var(flag_ira_region) Init(IRA_REGION_AUTODETECT)
1376 -fira-region=[one|all|mixed] Set regions for IRA
1377
1378 Enum
1379 Name(ira_region) Type(enum ira_region) UnknownError(unknown IRA region %qs)
1380
1381 EnumValue
1382 Enum(ira_region) String(one) Value(IRA_REGION_ONE)
1383
1384 EnumValue
1385 Enum(ira_region) String(all) Value(IRA_REGION_ALL)
1386
1387 EnumValue
1388 Enum(ira_region) String(mixed) Value(IRA_REGION_MIXED)
1389
1390 fira-hoist-pressure
1391 Common Report Var(flag_ira_hoist_pressure) Init(1) Optimization
1392 Use IRA based register pressure calculation
1393 in RTL hoist optimizations.
1394
1395 fira-loop-pressure
1396 Common Report Var(flag_ira_loop_pressure)
1397 Use IRA based register pressure calculation
1398 in RTL loop optimizations.
1399
1400 fira-share-save-slots
1401 Common Report Var(flag_ira_share_save_slots) Init(1)
1402 Share slots for saving different hard registers.
1403
1404 fira-share-spill-slots
1405 Common Report Var(flag_ira_share_spill_slots) Init(1)
1406 Share stack slots for spilled pseudo-registers.
1407
1408 fira-verbose=
1409 Common RejectNegative Joined UInteger Var(flag_ira_verbose) Init(5)
1410 -fira-verbose=<number>  Control IRA's level of diagnostic messages.
1411
1412 fivopts
1413 Common Report Var(flag_ivopts) Init(1) Optimization
1414 Optimize induction variables on trees
1415
1416 fjump-tables
1417 Common Var(flag_jump_tables) Init(1) Optimization
1418 Use jump tables for sufficiently large switch statements
1419
1420 fkeep-inline-functions
1421 Common Report Var(flag_keep_inline_functions)
1422 Generate code for functions even if they are fully inlined
1423
1424 fkeep-static-consts
1425 Common Report Var(flag_keep_static_consts) Init(1)
1426 Emit static const variables even if they are not used
1427
1428 fleading-underscore
1429 Common Report Var(flag_leading_underscore) Init(-1)
1430 Give external symbols a leading underscore
1431
1432 floop-optimize
1433 Common Ignore
1434 Does nothing.  Preserved for backward compatibility.
1435
1436 flto
1437 Common
1438 Enable link-time optimization.
1439
1440 flto=
1441 Common RejectNegative Joined Var(flag_lto)
1442 Link-time optimization with number of parallel jobs or jobserver.
1443
1444 flto-partition=1to1
1445 Common Var(flag_lto_partition_1to1)
1446 Partition symbols and vars at linktime based on object files they originate from
1447
1448 flto-partition=balanced
1449 Common Var(flag_lto_partition_balanced)
1450 Partition functions and vars at linktime into approximately same sized buckets
1451
1452 flto-partition=max
1453 Common Var(flag_lto_partition_max)
1454 Put every symbol into separate partition
1455
1456 flto-partition=none
1457 Common Var(flag_lto_partition_none)
1458 Disable partioning and streaming
1459
1460 ; The initial value of -1 comes from Z_DEFAULT_COMPRESSION in zlib.h.
1461 flto-compression-level=
1462 Common Joined RejectNegative UInteger Var(flag_lto_compression_level) Init(-1)
1463 -flto-compression-level=<number>        Use zlib compression level <number> for IL
1464
1465 flto-report
1466 Common Report Var(flag_lto_report) Init(0)
1467 Report various link-time optimization statistics
1468
1469 fmath-errno
1470 Common Report Var(flag_errno_math) Init(1) Optimization SetByCombined
1471 Set errno after built-in math functions
1472
1473 fmax-errors=
1474 Common Joined RejectNegative UInteger Var(flag_max_errors)
1475 -fmax-errors=<number>   Maximum number of errors to report
1476
1477 fmem-report
1478 Common Report Var(mem_report)
1479 Report on permanent memory allocation
1480
1481 fmem-report-wpa
1482 Common Report Var(mem_report_wpa)
1483 Report on permanent memory allocation in WPA only
1484
1485 ; This will attempt to merge constant section constants, if 1 only
1486 ; string constants and constants from constant pool, if 2 also constant
1487 ; variables.
1488 fmerge-all-constants
1489 Common Report Var(flag_merge_constants,2) Init(1) Optimization
1490 Attempt to merge identical constants and constant variables
1491
1492 fmerge-constants
1493 Common Report Var(flag_merge_constants,1) Optimization
1494 Attempt to merge identical constants across compilation units
1495
1496 fmerge-debug-strings
1497 Common Report Var(flag_merge_debug_strings) Init(1)
1498 Attempt to merge identical debug strings across compilation units
1499
1500 fmessage-length=
1501 Common RejectNegative Joined UInteger
1502 -fmessage-length=<number>       Limit diagnostics to <number> characters per line.  0 suppresses line-wrapping
1503
1504 fmodulo-sched
1505 Common Report Var(flag_modulo_sched) Optimization
1506 Perform SMS based modulo scheduling before the first scheduling pass
1507
1508 fmodulo-sched-allow-regmoves
1509 Common Report Var(flag_modulo_sched_allow_regmoves)
1510 Perform SMS based modulo scheduling with register moves allowed
1511
1512 fmove-loop-invariants
1513 Common Report Var(flag_move_loop_invariants) Init(1) Optimization
1514 Move loop invariant computations out of loops
1515
1516 fdce
1517 Common Var(flag_dce) Init(1) Optimization
1518 Use the RTL dead code elimination pass
1519
1520 fdse
1521 Common Var(flag_dse) Init(1) Optimization
1522 Use the RTL dead store elimination pass
1523
1524 freschedule-modulo-scheduled-loops
1525 Common Report Var(flag_resched_modulo_sched) Optimization
1526 Enable/Disable the traditional scheduling in loops that already passed modulo scheduling
1527
1528 fnon-call-exceptions
1529 Common Report Var(flag_non_call_exceptions) Optimization
1530 Support synchronous non-call exceptions
1531
1532 fomit-frame-pointer
1533 Common Report Var(flag_omit_frame_pointer) Optimization
1534 When possible do not generate stack frames
1535
1536 fopt-info
1537 Common Report Var(flag_opt_info) Optimization
1538 Enable all optimization info dumps on stderr
1539
1540 fopt-info-
1541 Common Joined RejectNegative Var(common_deferred_options) Defer
1542 -fopt-info[-<type>=filename]    Dump compiler optimization details
1543
1544 foptimize-register-move
1545 Common Report Var(flag_regmove) Optimization
1546 Do the full register move optimization pass
1547
1548 foptimize-sibling-calls
1549 Common Report Var(flag_optimize_sibling_calls) Optimization
1550 Optimize sibling and tail recursive calls
1551
1552 fpartial-inlining
1553 Common Report Var(flag_partial_inlining)
1554 Perform partial inlining
1555
1556 fpre-ipa-mem-report
1557 Common Report Var(pre_ipa_mem_report)
1558 Report on memory allocation before interprocedural optimization
1559
1560 fpost-ipa-mem-report
1561 Common Report Var(post_ipa_mem_report)
1562 Report on memory allocation before interprocedural optimization
1563
1564 fpack-struct
1565 Common Report Var(flag_pack_struct) Optimization
1566 Pack structure members together without holes
1567
1568 fpack-struct=
1569 Common RejectNegative Joined UInteger Optimization
1570 -fpack-struct=<number>  Set initial maximum structure member alignment
1571
1572 fpcc-struct-return
1573 Common Report Var(flag_pcc_struct_return,1) Init(DEFAULT_PCC_STRUCT_RETURN)
1574 Return small aggregates in memory, not registers
1575
1576 fpeel-loops
1577 Common Report Var(flag_peel_loops) Optimization
1578 Perform loop peeling
1579
1580 fpeephole
1581 Common Report Var(flag_no_peephole,0) Optimization
1582 Enable machine specific peephole optimizations
1583
1584 fpeephole2
1585 Common Report Var(flag_peephole2) Optimization
1586 Enable an RTL peephole pass before sched2
1587
1588 fPIC
1589 Common Report Var(flag_pic,2) Negative(fPIE)
1590 Generate position-independent code if possible (large mode)
1591
1592 fPIE
1593 Common Report Var(flag_pie,2) Negative(fpic)
1594 Generate position-independent code for executables if possible (large mode)
1595
1596 fpic
1597 Common Report Var(flag_pic,1) Negative(fpie)
1598 Generate position-independent code if possible (small mode)
1599
1600 fpie
1601 Common Report Var(flag_pie,1) Negative(fPIC)
1602 Generate position-independent code for executables if possible (small mode)
1603
1604 fplugin=
1605 Common Joined RejectNegative Var(common_deferred_options) Defer
1606 Specify a plugin to load
1607
1608 fplugin-arg-
1609 Common Joined RejectNegative Var(common_deferred_options) Defer
1610 -fplugin-arg-<name>-<key>[=<value>]     Specify argument <key>=<value> for plugin <name>
1611
1612 fpredictive-commoning
1613 Common Report Var(flag_predictive_commoning) Optimization
1614 Run predictive commoning optimization.
1615
1616 fprefetch-loop-arrays
1617 Common Report Var(flag_prefetch_loop_arrays) Init(-1) Optimization
1618 Generate prefetch instructions, if available, for arrays in loops
1619
1620 fprofile
1621 Common Report Var(profile_flag)
1622 Enable basic program profiling code
1623
1624 fprofile-arcs
1625 Common Report Var(profile_arc_flag)
1626 Insert arc-based program profiling code
1627
1628 fprofile-dir=
1629 Common Joined RejectNegative Var(profile_data_prefix)
1630 Set the top-level directory for storing the profile data.
1631 The default is 'pwd'.
1632
1633 fprofile-correction
1634 Common Report Var(flag_profile_correction)
1635 Enable correction of flow inconsistent profile data input
1636
1637 fprofile-generate
1638 Common
1639 Enable common options for generating profile info for profile feedback directed optimizations
1640
1641 fprofile-generate=
1642 Common Joined RejectNegative
1643 Enable common options for generating profile info for profile feedback directed optimizations, and set -fprofile-dir=
1644
1645 fprofile-use
1646 Common Var(flag_profile_use)
1647 Enable common options for performing profile feedback directed optimizations
1648
1649 fprofile-use=
1650 Common Joined RejectNegative
1651 Enable common options for performing profile feedback directed optimizations, and set -fprofile-dir=
1652
1653 fprofile-values
1654 Common Report Var(flag_profile_values)
1655 Insert code to profile values of expressions
1656
1657 fprofile-report
1658 Common Report Var(profile_report)
1659 Report on consistency of profile
1660
1661 frandom-seed
1662 Common Var(common_deferred_options) Defer
1663
1664 frandom-seed=
1665 Common Joined RejectNegative Var(common_deferred_options) Defer
1666 -frandom-seed=<string>  Make compile reproducible using <string>
1667
1668 ; This switch causes the command line that was used to create an
1669 ; object file to be recorded into the object file.  The exact format
1670 ; of this recording is target and binary file format dependent.
1671 ; It is related to the -fverbose-asm switch, but that switch only
1672 ; records information in the assembler output file as comments, so
1673 ; they never reach the object file.
1674 frecord-gcc-switches
1675 Common Report Var(flag_record_gcc_switches)
1676 Record gcc command line switches in the object file.
1677
1678 freg-struct-return
1679 Common Report Var(flag_pcc_struct_return,0) Optimization
1680 Return small aggregates in registers
1681
1682 fregmove
1683 Common Report Var(flag_regmove) Optimization
1684 Enables a register move optimization
1685
1686 frename-registers
1687 Common Report Var(flag_rename_registers) Init(2) Optimization
1688 Perform a register renaming optimization pass
1689
1690 freorder-blocks
1691 Common Report Var(flag_reorder_blocks) Optimization
1692 Reorder basic blocks to improve code placement
1693
1694 freorder-blocks-and-partition
1695 Common Report Var(flag_reorder_blocks_and_partition) Optimization
1696 Reorder basic blocks and partition into hot and cold sections
1697
1698 freorder-functions
1699 Common Report Var(flag_reorder_functions) Optimization
1700 Reorder functions to improve code placement
1701
1702 frerun-cse-after-loop
1703 Common Report Var(flag_rerun_cse_after_loop) Optimization
1704 Add a common subexpression elimination pass after loop optimizations
1705
1706 frerun-loop-opt
1707 Common Ignore
1708 Does nothing.  Preserved for backward compatibility.
1709
1710 frounding-math
1711 Common Report Var(flag_rounding_math) Optimization SetByCombined
1712 Disable optimizations that assume default FP rounding behavior
1713
1714 fsched-interblock
1715 Common Report Var(flag_schedule_interblock) Init(1) Optimization
1716 Enable scheduling across basic blocks
1717
1718 fsched-pressure
1719 Common Report Var(flag_sched_pressure) Init(0) Optimization
1720 Enable register pressure sensitive insn scheduling
1721
1722 fsched-spec
1723 Common Report Var(flag_schedule_speculative) Init(1) Optimization
1724 Allow speculative motion of non-loads
1725
1726 fsched-spec-load
1727 Common Report Var(flag_schedule_speculative_load) Optimization
1728 Allow speculative motion of some loads
1729
1730 fsched-spec-load-dangerous
1731 Common Report Var(flag_schedule_speculative_load_dangerous) Optimization
1732 Allow speculative motion of more loads
1733
1734 fsched-verbose=
1735 Common RejectNegative Joined UInteger Var(sched_verbose_param)
1736 -fsched-verbose=<number>        Set the verbosity level of the scheduler
1737
1738 fsched2-use-superblocks
1739 Common Report Var(flag_sched2_use_superblocks) Optimization
1740 If scheduling post reload, do superblock scheduling
1741
1742 fsched2-use-traces
1743 Common Ignore
1744 Does nothing.  Preserved for backward compatibility.
1745
1746 fschedule-insns
1747 Common Report Var(flag_schedule_insns) Optimization
1748 Reschedule instructions before register allocation
1749
1750 fschedule-insns2
1751 Common Report Var(flag_schedule_insns_after_reload) Optimization
1752 Reschedule instructions after register allocation
1753
1754 ; This flag should be on when a target implements non-trivial
1755 ; scheduling hooks, maybe saving some information for its own sake.
1756 ; On IA64, for example, this is used for correct bundling.
1757 fselective-scheduling
1758 Common Report Var(flag_selective_scheduling) Optimization
1759 Schedule instructions using selective scheduling algorithm
1760
1761 fselective-scheduling2
1762 Common Report Var(flag_selective_scheduling2) Optimization
1763 Run selective scheduling after reload
1764
1765 fsel-sched-pipelining
1766 Common Report Var(flag_sel_sched_pipelining) Init(0) Optimization
1767 Perform software pipelining of inner loops during selective scheduling
1768
1769 fsel-sched-pipelining-outer-loops
1770 Common Report Var(flag_sel_sched_pipelining_outer_loops) Init(0) Optimization
1771 Perform software pipelining of outer loops during selective scheduling
1772
1773 fsel-sched-reschedule-pipelined
1774 Common Report Var(flag_sel_sched_reschedule_pipelined) Init(0) Optimization
1775 Reschedule pipelined regions without pipelining
1776
1777 ; sched_stalled_insns means that insns can be moved prematurely from the queue
1778 ; of stalled insns into the ready list.
1779 fsched-stalled-insns
1780 Common Report Var(flag_sched_stalled_insns) Optimization UInteger
1781 Allow premature scheduling of queued insns
1782
1783 fsched-stalled-insns=
1784 Common RejectNegative Joined UInteger
1785 -fsched-stalled-insns=<number>  Set number of queued insns that can be prematurely scheduled
1786
1787 ; sched_stalled_insns_dep controls how many recently scheduled cycles will
1788 ; be examined for a dependency on a stalled insn that is candidate for
1789 ; premature removal from the queue of stalled insns into the ready list (has
1790 ; an effect only if the flag 'sched_stalled_insns' is set).
1791 fsched-stalled-insns-dep
1792 Common Report Var(flag_sched_stalled_insns_dep,1) Init(1) Optimization UInteger
1793 Set dependence distance checking in premature scheduling of queued insns
1794
1795 fsched-stalled-insns-dep=
1796 Common RejectNegative Joined UInteger
1797 -fsched-stalled-insns-dep=<number>      Set dependence distance checking in premature scheduling of queued insns
1798
1799 fsched-group-heuristic
1800 Common Report Var(flag_sched_group_heuristic) Init(1) Optimization
1801 Enable the group heuristic in the scheduler
1802
1803 fsched-critical-path-heuristic
1804 Common Report Var(flag_sched_critical_path_heuristic) Init(1) Optimization
1805 Enable the critical path heuristic in the scheduler
1806
1807 fsched-spec-insn-heuristic
1808 Common Report Var(flag_sched_spec_insn_heuristic) Init(1) Optimization
1809 Enable the speculative instruction heuristic in the scheduler
1810
1811 fsched-rank-heuristic
1812 Common Report Var(flag_sched_rank_heuristic) Init(1) Optimization
1813 Enable the rank heuristic in the scheduler
1814
1815 fsched-last-insn-heuristic
1816 Common Report Var(flag_sched_last_insn_heuristic) Init(1) Optimization
1817 Enable the last instruction heuristic in the scheduler
1818
1819 fsched-dep-count-heuristic
1820 Common Report Var(flag_sched_dep_count_heuristic) Init(1) Optimization
1821 Enable the dependent count heuristic in the scheduler
1822
1823 fsection-anchors
1824 Common Report Var(flag_section_anchors) Optimization
1825 Access data in the same section from shared anchor points
1826
1827 fsee
1828 Common Ignore
1829 Does nothing.  Preserved for backward compatibility.
1830
1831 fzee
1832 Common Ignore
1833 Does nothing.  Preserved for backward compatibility.
1834
1835 free
1836 Common Report Var(flag_ree) Init(0)
1837 Turn on Redundant Extensions Elimination pass.
1838
1839 fshow-column
1840 Common Report Var(flag_show_column) Init(1)
1841 Show column numbers in diagnostics, when available.  Default on
1842
1843 fshrink-wrap
1844 Common Report Var(flag_shrink_wrap) Optimization
1845 Emit function prologues only before parts of the function that need it,
1846 rather than at the top of the function.
1847
1848 fsignaling-nans
1849 Common Report Var(flag_signaling_nans) Optimization SetByCombined
1850 Disable optimizations observable by IEEE signaling NaNs
1851
1852 fsigned-zeros
1853 Common Report Var(flag_signed_zeros) Init(1) Optimization SetByCombined
1854 Disable floating point optimizations that ignore the IEEE signedness of zero
1855
1856 fsingle-precision-constant
1857 Common Report Var(flag_single_precision_constant) Optimization
1858 Convert floating point constants to single precision constants
1859
1860 fsplit-ivs-in-unroller
1861 Common Report Var(flag_split_ivs_in_unroller) Init(1) Optimization
1862 Split lifetimes of induction variables when loops are unrolled
1863
1864 fsplit-stack
1865 Common Report Var(flag_split_stack) Init(-1)
1866 Generate discontiguous stack frames
1867
1868 fsplit-wide-types
1869 Common Report Var(flag_split_wide_types) Optimization
1870 Split wide types into independent registers
1871
1872 fvariable-expansion-in-unroller
1873 Common Report Var(flag_variable_expansion_in_unroller) Optimization
1874 Apply variable expansion when loops are unrolled
1875
1876 fstack-check=
1877 Common Report RejectNegative Joined
1878 -fstack-check=[no|generic|specific]     Insert stack checking code into the program
1879
1880 fstack-check
1881 Common Alias(fstack-check=, specific, no)
1882 Insert stack checking code into the program.  Same as -fstack-check=specific
1883
1884 fstack-limit
1885 Common Var(common_deferred_options) Defer
1886
1887 fstack-limit-register=
1888 Common RejectNegative Joined Var(common_deferred_options) Defer
1889 -fstack-limit-register=<register>       Trap if the stack goes past <register>
1890
1891 fstack-limit-symbol=
1892 Common RejectNegative Joined Var(common_deferred_options) Defer
1893 -fstack-limit-symbol=<name>     Trap if the stack goes past symbol <name>
1894
1895 fstack-protector
1896 Common Report Var(flag_stack_protect, 1)
1897 Use propolice as a stack protection method
1898
1899 fstack-protector-all
1900 Common Report RejectNegative Var(flag_stack_protect, 2)
1901 Use a stack protection method for every function
1902
1903 fstack-usage
1904 Common RejectNegative Var(flag_stack_usage)
1905 Output stack usage information on a per-function basis
1906
1907 fstrength-reduce
1908 Common Ignore
1909 Does nothing.  Preserved for backward compatibility.
1910
1911 ; Nonzero if we should do (language-dependent) alias analysis.
1912 ; Typically, this analysis will assume that expressions of certain
1913 ; types do not alias expressions of certain other types.  Only used
1914 ; if alias analysis (in general) is enabled.
1915 fstrict-aliasing
1916 Common Report Var(flag_strict_aliasing) Optimization
1917 Assume strict aliasing rules apply
1918
1919 fstrict-overflow
1920 Common Report Var(flag_strict_overflow)
1921 Treat signed overflow as undefined
1922
1923 fsync-libcalls
1924 Common Report Var(flag_sync_libcalls) Init(1)
1925 Implement __atomic operations via libcalls to legacy __sync functions
1926
1927 fsyntax-only
1928 Common Report Var(flag_syntax_only)
1929 Check for syntax errors, then stop
1930
1931 ftest-coverage
1932 Common Report Var(flag_test_coverage)
1933 Create data files needed by \"gcov\"
1934
1935 fthread-jumps
1936 Common Report Var(flag_thread_jumps) Optimization
1937 Perform jump threading optimizations
1938
1939 ftime-report
1940 Common Report Var(time_report)
1941 Report the time taken by each compiler pass
1942
1943 ftls-model=
1944 Common Joined RejectNegative Enum(tls_model) Var(flag_tls_default) Init(TLS_MODEL_GLOBAL_DYNAMIC)
1945 -ftls-model=[global-dynamic|local-dynamic|initial-exec|local-exec]      Set the default thread-local storage code generation model
1946
1947 Enum
1948 Name(tls_model) Type(enum tls_model) UnknownError(unknown TLS model %qs)
1949
1950 EnumValue
1951 Enum(tls_model) String(global-dynamic) Value(TLS_MODEL_GLOBAL_DYNAMIC)
1952
1953 EnumValue
1954 Enum(tls_model) String(local-dynamic) Value(TLS_MODEL_LOCAL_DYNAMIC)
1955
1956 EnumValue
1957 Enum(tls_model) String(initial-exec) Value(TLS_MODEL_INITIAL_EXEC)
1958
1959 EnumValue
1960 Enum(tls_model) String(local-exec) Value(TLS_MODEL_LOCAL_EXEC)
1961
1962 ftoplevel-reorder
1963 Common Report Var(flag_toplevel_reorder) Init(2) Optimization
1964 Reorder top level functions, variables, and asms
1965
1966 ftracer
1967 Common Report Var(flag_tracer)
1968 Perform superblock formation via tail duplication
1969
1970 ; Zero means that floating-point math operations cannot generate a
1971 ; (user-visible) trap.  This is the case, for example, in nonstop
1972 ; IEEE 754 arithmetic.
1973 ftrapping-math
1974 Common Report Var(flag_trapping_math) Init(1) Optimization SetByCombined
1975 Assume floating-point operations can trap
1976
1977 ftrapv
1978 Common Report Var(flag_trapv) Optimization
1979 Trap for signed overflow in addition, subtraction and multiplication
1980
1981 ftree-ccp
1982 Common Report Var(flag_tree_ccp) Optimization
1983 Enable SSA-CCP optimization on trees
1984
1985 ftree-bit-ccp
1986 Common Report Var(flag_tree_bit_ccp) Optimization
1987 Enable SSA-BIT-CCP optimization on trees
1988
1989 ftree-store-ccp
1990 Common Ignore
1991 Does nothing.  Preserved for backward compatibility.
1992
1993 ftree-ch
1994 Common Report Var(flag_tree_ch) Optimization
1995 Enable loop header copying on trees
1996
1997 ftree-coalesce-inlined-vars
1998 Common Report Var(flag_ssa_coalesce_vars,1) Init(2) RejectNegative Optimization
1999 Enable coalescing of copy-related user variables that are inlined
2000
2001 ftree-coalesce-vars
2002 Common Report Var(flag_ssa_coalesce_vars,2) Optimization
2003 Enable coalescing of all copy-related user variables
2004
2005 ftree-copyrename
2006 Common Report Var(flag_tree_copyrename) Optimization
2007 Replace SSA temporaries with better names in copies
2008
2009 ftree-copy-prop
2010 Common Report Var(flag_tree_copy_prop) Optimization
2011 Enable copy propagation on trees
2012
2013 ftree-store-copy-prop
2014 Common Ignore
2015 Does nothing.  Preserved for backward compatibility.
2016
2017 ftree-cselim
2018 Common Report Var(flag_tree_cselim) Init(2) Optimization
2019 Transform condition stores into unconditional ones
2020
2021 ftree-switch-conversion
2022 Common Report Var(flag_tree_switch_conversion) Optimization
2023 Perform conversions of switch initializations.
2024
2025 ftree-dce
2026 Common Report Var(flag_tree_dce) Optimization
2027 Enable SSA dead code elimination optimization on trees
2028
2029 ftree-dominator-opts
2030 Common Report Var(flag_tree_dom) Optimization
2031 Enable dominator optimizations
2032
2033 ftree-tail-merge
2034 Common Report Var(flag_tree_tail_merge) Optimization
2035 Enable tail merging on trees
2036
2037 ftree-dse
2038 Common Report Var(flag_tree_dse) Optimization
2039 Enable dead store elimination
2040
2041 ftree-forwprop
2042 Common Report Var(flag_tree_forwprop) Init(1) Optimization
2043 Enable forward propagation on trees
2044
2045 ftree-fre
2046 Common Report Var(flag_tree_fre) Optimization
2047 Enable Full Redundancy Elimination (FRE) on trees
2048
2049 foptimize-strlen
2050 Common Report Var(flag_optimize_strlen) Optimization
2051 Enable string length optimizations on trees
2052
2053 ftree-loop-distribution
2054 Common Report Var(flag_tree_loop_distribution) Optimization
2055 Enable loop distribution on trees
2056
2057 ftree-loop-distribute-patterns
2058 Common Report Var(flag_tree_loop_distribute_patterns) Optimization
2059 Enable loop distribution for patterns transformed into a library call
2060
2061 ftree-loop-im
2062 Common Report Var(flag_tree_loop_im) Init(1) Optimization
2063 Enable loop invariant motion on trees
2064
2065 ftree-loop-linear
2066 Common Alias(floop-interchange)
2067 Enable loop interchange transforms.  Same as -floop-interchange
2068
2069 ftree-loop-ivcanon
2070 Common Report Var(flag_tree_loop_ivcanon) Init(1) Optimization
2071 Create canonical induction variables in loops
2072
2073 ftree-loop-optimize
2074 Common Report Var(flag_tree_loop_optimize) Init(1) Optimization
2075 Enable loop optimizations on tree level
2076
2077 ftree-parallelize-loops=
2078 Common Report Joined RejectNegative UInteger Var(flag_tree_parallelize_loops) Init(1)
2079 Enable automatic parallelization of loops
2080
2081 ftree-phiprop
2082 Common Report Var(flag_tree_phiprop) Init(1) Optimization
2083 Enable hoisting loads from conditional pointers.
2084
2085 ftree-pre
2086 Common Report Var(flag_tree_pre) Optimization
2087 Enable SSA-PRE optimization on trees
2088
2089 ftree-partial-pre
2090 Common Report Var(flag_tree_partial_pre) Optimization
2091 In SSA-PRE optimization on trees, enable partial-partial redundancy elimination
2092
2093 ftree-pta
2094 Common Report Var(flag_tree_pta) Init(1) Optimization
2095 Perform function-local points-to analysis on trees.
2096
2097 ftree-reassoc
2098 Common Report Var(flag_tree_reassoc) Init(1) Optimization
2099 Enable reassociation on tree level
2100
2101 ftree-salias
2102 Common Ignore
2103 Does nothing.  Preserved for backward compatibility.
2104
2105 ftree-sink
2106 Common Report Var(flag_tree_sink) Optimization
2107 Enable SSA code sinking on trees
2108
2109 ftree-slsr
2110 Common Report Var(flag_tree_slsr) Optimization
2111 Perform straight-line strength reduction
2112
2113 ftree-sra
2114 Common Report Var(flag_tree_sra) Optimization
2115 Perform scalar replacement of aggregates
2116
2117 ftree-ter
2118 Common Report Var(flag_tree_ter) Optimization
2119 Replace temporary expressions in the SSA->normal pass
2120
2121 ftree-lrs
2122 Common Report Var(flag_tree_live_range_split) Optimization
2123 Perform live range splitting during the SSA->normal pass
2124
2125 ftree-vrp
2126 Common Report Var(flag_tree_vrp) Init(0) Optimization
2127 Perform Value Range Propagation on trees
2128
2129 funit-at-a-time
2130 Common Report Var(flag_unit_at_a_time) Init(1) Optimization
2131 Compile whole compilation unit at a time
2132
2133 funroll-loops
2134 Common Report Var(flag_unroll_loops) Optimization
2135 Perform loop unrolling when iteration count is known
2136
2137 funroll-all-loops
2138 Common Report Var(flag_unroll_all_loops) Optimization
2139 Perform loop unrolling for all loops
2140
2141 ; Nonzero means that loop optimizer may assume that the induction variables
2142 ; that control loops do not overflow and that the loops with nontrivial
2143 ; exit condition are not infinite
2144 funsafe-loop-optimizations
2145 Common Report Var(flag_unsafe_loop_optimizations) Optimization
2146 Allow loop optimizations to assume that the loops behave in normal way
2147
2148 fassociative-math
2149 Common Report Var(flag_associative_math) SetByCombined
2150 Allow optimization for floating-point arithmetic which may change the
2151 result of the operation due to rounding.
2152
2153 freciprocal-math
2154 Common Report Var(flag_reciprocal_math) SetByCombined
2155 Same as -fassociative-math for expressions which include division.
2156
2157 ; Nonzero means that unsafe floating-point math optimizations are allowed
2158 ; for the sake of speed.  IEEE compliance is not guaranteed, and operations
2159 ; are allowed to assume that their arguments and results are "normal"
2160 ; (e.g., nonnegative for SQRT).
2161 funsafe-math-optimizations
2162 Common Report Var(flag_unsafe_math_optimizations) Optimization SetByCombined
2163 Allow math optimizations that may violate IEEE or ISO standards
2164
2165 funswitch-loops
2166 Common Report Var(flag_unswitch_loops) Optimization
2167 Perform loop unswitching
2168
2169 funwind-tables
2170 Common Report Var(flag_unwind_tables) Optimization
2171 Just generate unwind tables for exception handling
2172
2173 fuse-linker-plugin
2174 Common Undocumented
2175
2176 ; Positive if we should track variables, negative if we should run
2177 ; the var-tracking pass only to discard debug annotations, zero if
2178 ; we're not to run it.  When flag_var_tracking == 2 (AUTODETECT_VALUE) it
2179 ; will be set according to optimize, debug_info_level and debug_hooks
2180 ; in process_options ().
2181 fvar-tracking
2182 Common Report Var(flag_var_tracking) Init(2) Optimization
2183 Perform variable tracking
2184
2185 ; Positive if we should track variables at assignments, negative if
2186 ; we should run the var-tracking pass only to discard debug
2187 ; annotations.  When flag_var_tracking_assignments ==
2188 ; AUTODETECT_VALUE it will be set according to flag_var_tracking.
2189 fvar-tracking-assignments
2190 Common Report Var(flag_var_tracking_assignments) Init(2) Optimization
2191 Perform variable tracking by annotating assignments
2192
2193 ; Nonzero if we should toggle flag_var_tracking_assignments after
2194 ; processing options and computing its default.  */
2195 fvar-tracking-assignments-toggle
2196 Common Report Var(flag_var_tracking_assignments_toggle) Optimization
2197 Toggle -fvar-tracking-assignments
2198
2199 ; Positive if we should track uninitialized variables, negative if
2200 ; we should run the var-tracking pass only to discard debug
2201 ; annotations.  When flag_var_tracking_uninit == AUTODETECT_VALUE it
2202 ; will be set according to flag_var_tracking.
2203 fvar-tracking-uninit
2204 Common Report Var(flag_var_tracking_uninit) Optimization
2205 Perform variable tracking and also tag variables that are uninitialized
2206
2207 ftree-vectorize
2208 Common Report Var(flag_tree_vectorize) Optimization
2209 Enable loop vectorization on trees
2210
2211 ftree-vectorizer-verbose=
2212 Common RejectNegative Joined UInteger Var(common_deferred_options) Defer
2213 -ftree-vectorizer-verbose=<number>      This switch is deprecated. Use -fopt-info instead.
2214
2215 ftree-slp-vectorize
2216 Common Report Var(flag_tree_slp_vectorize) Init(2) Optimization
2217 Enable basic block vectorization (SLP) on trees
2218
2219 fvect-cost-model
2220 Common Report Var(flag_vect_cost_model) Optimization
2221 Enable use of cost model in vectorization
2222
2223 ftree-vect-loop-version
2224 Common Report Var(flag_tree_vect_loop_version) Init(1) Optimization
2225 Enable loop versioning when doing loop vectorization on trees
2226
2227 ftree-scev-cprop
2228 Common Report Var(flag_tree_scev_cprop) Init(1) Optimization
2229 Enable copy propagation of scalar-evolution information.
2230
2231 ; -fverbose-asm causes extra commentary information to be produced in
2232 ; the generated assembly code (to make it more readable).  This option
2233 ; is generally only of use to those who actually need to read the
2234 ; generated assembly code (perhaps while debugging the compiler itself).
2235 ; -fno-verbose-asm, the default, causes the extra information
2236 ; to not be added and is useful when comparing two assembler files.
2237 fverbose-asm
2238 Common Report Var(flag_verbose_asm)
2239 Add extra commentary to assembler output
2240
2241 fvisibility=
2242 Common Joined RejectNegative Enum(symbol_visibility) Var(default_visibility) Init(VISIBILITY_DEFAULT)
2243 -fvisibility=[default|internal|hidden|protected]        Set the default symbol visibility
2244
2245 Enum
2246 Name(symbol_visibility) Type(enum symbol_visibility) UnknownError(unrecognized visibility value %qs)
2247
2248 EnumValue
2249 Enum(symbol_visibility) String(default) Value(VISIBILITY_DEFAULT)
2250
2251 EnumValue
2252 Enum(symbol_visibility) String(internal) Value(VISIBILITY_INTERNAL)
2253
2254 EnumValue
2255 Enum(symbol_visibility) String(hidden) Value(VISIBILITY_HIDDEN)
2256
2257 EnumValue
2258 Enum(symbol_visibility) String(protected) Value(VISIBILITY_PROTECTED)
2259
2260 fvpt
2261 Common Report Var(flag_value_profile_transformations) Optimization
2262 Use expression value profiles in optimizations
2263
2264 fweb
2265 Common Report Var(flag_web) Init(2) Optimization
2266 Construct webs and split unrelated uses of single variable
2267
2268 ftree-builtin-call-dce
2269 Common Report Var(flag_tree_builtin_call_dce) Init(0) Optimization
2270 Enable conditional dead code elimination for builtin calls
2271
2272 fwhole-program
2273 Common Report Var(flag_whole_program) Init(0) Optimization
2274 Perform whole program optimizations
2275
2276 fwrapv
2277 Common Report Var(flag_wrapv) Optimization
2278 Assume signed arithmetic overflow wraps around
2279
2280 fzero-initialized-in-bss
2281 Common Report Var(flag_zero_initialized_in_bss) Init(1)
2282 Put zero initialized data in the bss section
2283
2284 g
2285 Common JoinedOrMissing
2286 Generate debug information in default format
2287
2288 gcoff
2289 Common JoinedOrMissing Negative(gdwarf-)
2290 Generate debug information in COFF format
2291
2292 gdwarf-
2293 Common Joined UInteger Var(dwarf_version) Init(4) Negative(gstabs)
2294 Generate debug information in DWARF v2 (or later) format
2295
2296 ggdb
2297 Common JoinedOrMissing
2298 Generate debug information in default extended format
2299
2300 gno-pubnames
2301 Common RejectNegative Var(debug_generate_pub_sections, 0) Init(-1)
2302 Don't generate DWARF pubnames and pubtypes sections.
2303
2304 gpubnames
2305 Common RejectNegative Var(debug_generate_pub_sections, 1)
2306 Generate DWARF pubnames and pubtypes sections.
2307
2308 gno-record-gcc-switches
2309 Common RejectNegative Var(dwarf_record_gcc_switches,0) Init(1)
2310 Don't record gcc command line switches in DWARF DW_AT_producer.
2311
2312 grecord-gcc-switches
2313 Common RejectNegative Var(dwarf_record_gcc_switches,1)
2314 Record gcc command line switches in DWARF DW_AT_producer.
2315
2316 gno-split-dwarf
2317 Common Driver RejectNegative Var(dwarf_split_debug_info,0) Init(0)
2318 Don't generate debug information in separate .dwo files
2319
2320 gsplit-dwarf
2321 Common Driver RejectNegative Var(dwarf_split_debug_info,1)
2322 Generate debug information in separate .dwo files
2323
2324 gstabs
2325 Common JoinedOrMissing Negative(gstabs+)
2326 Generate debug information in STABS format
2327
2328 gstabs+
2329 Common JoinedOrMissing Negative(gvms)
2330 Generate debug information in extended STABS format
2331
2332 gno-strict-dwarf
2333 Common RejectNegative Var(dwarf_strict,0) Init(0)
2334 Emit DWARF additions beyond selected version
2335
2336 gstrict-dwarf
2337 Common Report RejectNegative Var(dwarf_strict,1)
2338 Don't emit DWARF additions beyond selected version
2339
2340 gtoggle
2341 Common Report Var(flag_gtoggle)
2342 Toggle debug information generation
2343
2344 gvms
2345 Common JoinedOrMissing Negative(gxcoff)
2346 Generate debug information in VMS format
2347
2348 gxcoff
2349 Common JoinedOrMissing Negative(gxcoff+)
2350 Generate debug information in XCOFF format
2351
2352 gxcoff+
2353 Common JoinedOrMissing Negative(gcoff)
2354 Generate debug information in extended XCOFF format
2355
2356 h
2357 Driver Joined Separate
2358
2359 iplugindir=
2360 Common Joined Var(plugindir_string) Init(0)
2361 -iplugindir=<dir>       Set <dir> to be the default plugin directory
2362
2363 imultiarch
2364 Common Joined Separate RejectDriver Var(imultiarch) Init(0)
2365 -imultiarch <dir>       Set <dir> to be the multiarch include subdirectory
2366
2367 l
2368 Driver Joined Separate
2369
2370 n
2371 Driver
2372
2373 no-canonical-prefixes
2374 Driver
2375
2376 nodefaultlibs
2377 Driver
2378
2379 nostartfiles
2380 Driver
2381
2382 nostdlib
2383 Driver
2384
2385 o
2386 Common Driver Joined Separate Var(asm_file_name) MissingArgError(missing filename after %qs)
2387 -o <file>       Place output into <file>
2388
2389 p
2390 Common Var(profile_flag)
2391 Enable function profiling
2392
2393 pass-exit-codes
2394 Driver Var(pass_exit_codes)
2395
2396 pedantic
2397 Common Alias(Wpedantic)
2398
2399 pedantic-errors
2400 Common Var(flag_pedantic_errors)
2401 Like -pedantic but issue them as errors
2402
2403 pg
2404 Driver
2405
2406 pipe
2407 Driver Var(use_pipes)
2408
2409 print-file-name=
2410 Driver JoinedOrMissing Var(print_file_name)
2411
2412 print-libgcc-file-name
2413 Driver
2414
2415 print-multi-directory
2416 Driver Var(print_multi_directory)
2417
2418 print-multi-lib
2419 Driver Var(print_multi_lib)
2420
2421 print-multi-os-directory
2422 Driver Var(print_multi_os_directory)
2423
2424 print-multiarch
2425 Driver Var(print_multiarch)
2426
2427 print-prog-name=
2428 Driver JoinedOrMissing Var(print_prog_name)
2429
2430 print-search-dirs
2431 Driver Var(print_search_dirs)
2432
2433 print-sysroot
2434 Driver Var(print_sysroot)
2435
2436 print-sysroot-headers-suffix
2437 Driver Var(print_sysroot_headers_suffix)
2438
2439 quiet
2440 Common Var(quiet_flag) RejectDriver
2441 Do not display functions compiled or elapsed time
2442
2443 r
2444 Driver
2445
2446 s
2447 Driver
2448
2449 save-temps
2450 Driver
2451
2452 save-temps=
2453 Driver Joined
2454
2455 t
2456 Driver
2457
2458 time
2459 Driver Var(report_times)
2460
2461 time=
2462 Driver JoinedOrMissing
2463
2464 u
2465 Driver Joined Separate
2466
2467 undef
2468 Driver
2469 ; C option, but driver must not handle as "-u ndef".
2470
2471 v
2472 Common Driver Var(verbose_flag)
2473 Enable verbose output
2474
2475 version
2476 Common Var(version_flag) RejectDriver
2477 Display the compiler's version
2478
2479 w
2480 Common Var(inhibit_warnings)
2481 Suppress warnings
2482
2483 wrapper
2484 Driver Separate Var(wrapper_string)
2485
2486 x
2487 Driver Joined Separate
2488
2489 shared
2490 Driver RejectNegative Negative(pie)
2491 Create a shared library
2492
2493 shared-libgcc
2494 Driver
2495
2496 specs
2497 Driver Separate Alias(specs=)
2498
2499 specs=
2500 Driver Joined
2501
2502 static
2503 Driver
2504
2505 static-libgcc
2506 Driver
2507
2508 static-libgfortran
2509 Driver
2510 ; Documented for Fortran, but always accepted by driver.
2511
2512 static-libstdc++
2513 Driver
2514
2515 static-libgo
2516 Driver
2517 ; Documented for Go, but always accepted by driver.
2518
2519 symbolic
2520 Driver
2521
2522 pie
2523 Driver RejectNegative Negative(shared)
2524 Create a position independent executable
2525
2526 z
2527 Driver Joined Separate
2528
2529 ; This comment is to ensure we retain the blank line above.