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.
 789 ;    First selectable in G++ 4.8.
 790 ; Additional positive integers will be assigned as new versions of
 791 ; the ABI become the default version of the ABI.
 792 fabi-version=
 793 Common Joined RejectNegative UInteger Var(flag_abi_version) Init(2)
 794
 795 falign-functions
 796 Common Report Var(align_functions,0) Optimization UInteger
 797 Align the start of functions
 798
 799 falign-functions=
 800 Common RejectNegative Joined UInteger Var(align_functions)
 801
 802 falign-jumps
 803 Common Report Var(align_jumps,0) Optimization UInteger
 804 Align labels which are only reached by jumping
 805
 806 falign-jumps=
 807 Common RejectNegative Joined UInteger Var(align_jumps)
 808
 809 falign-labels
 810 Common Report Var(align_labels,0) Optimization UInteger
 811 Align all labels
 812
 813 falign-labels=
 814 Common RejectNegative Joined UInteger Var(align_labels)
 815
 816 falign-loops
 817 Common Report Var(align_loops,0) Optimization UInteger
 818 Align the start of loops
 819
 820 falign-loops=
 821 Common RejectNegative Joined UInteger Var(align_loops)
 822
 823 fargument-alias
 824 Common Ignore
 825 Does nothing. Preserved for backward compatibility.
 826
 827 fargument-noalias
 828 Common Ignore
 829 Does nothing. Preserved for backward compatibility.
 830
 831 fargument-noalias-global
 832 Common Ignore
 833 Does nothing. Preserved for backward compatibility.
 834
 835 fargument-noalias-anything
 836 Common Ignore
 837 Does nothing. Preserved for backward compatibility.
 838
 839 fsanitize=address
 840 Common Report Var(flag_asan)
 841 Enable AddressSanitizer, a memory error detector
 842
 843 fsanitize=thread
 844 Common Report Var(flag_tsan)
 845 Enable ThreadSanitizer, a data race 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-ld=bfd
2174 Common Negative(fuse-ld=gold)
2175 Use the bfd linker instead of the default linker
2176
2177 fuse-ld=gold
2178 Common Negative(fuse-ld=bfd)
2179 Use the gold linker instead of the default linker
2180
2181 fuse-linker-plugin
2182 Common Undocumented
2183
2184 ; Positive if we should track variables, negative if we should run
2185 ; the var-tracking pass only to discard debug annotations, zero if
2186 ; we're not to run it.  When flag_var_tracking == 2 (AUTODETECT_VALUE) it
2187 ; will be set according to optimize, debug_info_level and debug_hooks
2188 ; in process_options ().
2189 fvar-tracking
2190 Common Report Var(flag_var_tracking) Init(2) Optimization
2191 Perform variable tracking
2192
2193 ; Positive if we should track variables at assignments, negative if
2194 ; we should run the var-tracking pass only to discard debug
2195 ; annotations.  When flag_var_tracking_assignments ==
2196 ; AUTODETECT_VALUE it will be set according to flag_var_tracking.
2197 fvar-tracking-assignments
2198 Common Report Var(flag_var_tracking_assignments) Init(2) Optimization
2199 Perform variable tracking by annotating assignments
2200
2201 ; Nonzero if we should toggle flag_var_tracking_assignments after
2202 ; processing options and computing its default.  */
2203 fvar-tracking-assignments-toggle
2204 Common Report Var(flag_var_tracking_assignments_toggle) Optimization
2205 Toggle -fvar-tracking-assignments
2206
2207 ; Positive if we should track uninitialized variables, negative if
2208 ; we should run the var-tracking pass only to discard debug
2209 ; annotations.  When flag_var_tracking_uninit == AUTODETECT_VALUE it
2210 ; will be set according to flag_var_tracking.
2211 fvar-tracking-uninit
2212 Common Report Var(flag_var_tracking_uninit) Optimization
2213 Perform variable tracking and also tag variables that are uninitialized
2214
2215 ftree-vectorize
2216 Common Report Var(flag_tree_vectorize) Optimization
2217 Enable loop vectorization on trees
2218
2219 ftree-vectorizer-verbose=
2220 Common RejectNegative Joined UInteger Var(common_deferred_options) Defer
2221 -ftree-vectorizer-verbose=<number>      This switch is deprecated. Use -fopt-info instead.
2222
2223 ftree-slp-vectorize
2224 Common Report Var(flag_tree_slp_vectorize) Init(2) Optimization
2225 Enable basic block vectorization (SLP) on trees
2226
2227 fvect-cost-model
2228 Common Report Var(flag_vect_cost_model) Optimization
2229 Enable use of cost model in vectorization
2230
2231 ftree-vect-loop-version
2232 Common Report Var(flag_tree_vect_loop_version) Init(1) Optimization
2233 Enable loop versioning when doing loop vectorization on trees
2234
2235 ftree-scev-cprop
2236 Common Report Var(flag_tree_scev_cprop) Init(1) Optimization
2237 Enable copy propagation of scalar-evolution information.
2238
2239 ; -fverbose-asm causes extra commentary information to be produced in
2240 ; the generated assembly code (to make it more readable).  This option
2241 ; is generally only of use to those who actually need to read the
2242 ; generated assembly code (perhaps while debugging the compiler itself).
2243 ; -fno-verbose-asm, the default, causes the extra information
2244 ; to not be added and is useful when comparing two assembler files.
2245 fverbose-asm
2246 Common Report Var(flag_verbose_asm)
2247 Add extra commentary to assembler output
2248
2249 fvisibility=
2250 Common Joined RejectNegative Enum(symbol_visibility) Var(default_visibility) Init(VISIBILITY_DEFAULT)
2251 -fvisibility=[default|internal|hidden|protected]        Set the default symbol visibility
2252
2253 Enum
2254 Name(symbol_visibility) Type(enum symbol_visibility) UnknownError(unrecognized visibility value %qs)
2255
2256 EnumValue
2257 Enum(symbol_visibility) String(default) Value(VISIBILITY_DEFAULT)
2258
2259 EnumValue
2260 Enum(symbol_visibility) String(internal) Value(VISIBILITY_INTERNAL)
2261
2262 EnumValue
2263 Enum(symbol_visibility) String(hidden) Value(VISIBILITY_HIDDEN)
2264
2265 EnumValue
2266 Enum(symbol_visibility) String(protected) Value(VISIBILITY_PROTECTED)
2267
2268 fvpt
2269 Common Report Var(flag_value_profile_transformations) Optimization
2270 Use expression value profiles in optimizations
2271
2272 fweb
2273 Common Report Var(flag_web) Init(2) Optimization
2274 Construct webs and split unrelated uses of single variable
2275
2276 ftree-builtin-call-dce
2277 Common Report Var(flag_tree_builtin_call_dce) Init(0) Optimization
2278 Enable conditional dead code elimination for builtin calls
2279
2280 fwhole-program
2281 Common Report Var(flag_whole_program) Init(0) Optimization
2282 Perform whole program optimizations
2283
2284 fwrapv
2285 Common Report Var(flag_wrapv) Optimization
2286 Assume signed arithmetic overflow wraps around
2287
2288 fzero-initialized-in-bss
2289 Common Report Var(flag_zero_initialized_in_bss) Init(1)
2290 Put zero initialized data in the bss section
2291
2292 g
2293 Common JoinedOrMissing
2294 Generate debug information in default format
2295
2296 gcoff
2297 Common JoinedOrMissing Negative(gdwarf-)
2298 Generate debug information in COFF format
2299
2300 gdwarf-
2301 Common Joined UInteger Var(dwarf_version) Init(4) Negative(gstabs)
2302 Generate debug information in DWARF v2 (or later) format
2303
2304 ggdb
2305 Common JoinedOrMissing
2306 Generate debug information in default extended format
2307
2308 gno-pubnames
2309 Common RejectNegative Var(debug_generate_pub_sections, 0) Init(-1)
2310 Don't generate DWARF pubnames and pubtypes sections.
2311
2312 gpubnames
2313 Common RejectNegative Var(debug_generate_pub_sections, 1)
2314 Generate DWARF pubnames and pubtypes sections.
2315
2316 gno-record-gcc-switches
2317 Common RejectNegative Var(dwarf_record_gcc_switches,0) Init(1)
2318 Don't record gcc command line switches in DWARF DW_AT_producer.
2319
2320 grecord-gcc-switches
2321 Common RejectNegative Var(dwarf_record_gcc_switches,1)
2322 Record gcc command line switches in DWARF DW_AT_producer.
2323
2324 gno-split-dwarf
2325 Common Driver RejectNegative Var(dwarf_split_debug_info,0) Init(0)
2326 Don't generate debug information in separate .dwo files
2327
2328 gsplit-dwarf
2329 Common Driver RejectNegative Var(dwarf_split_debug_info,1)
2330 Generate debug information in separate .dwo files
2331
2332 gstabs
2333 Common JoinedOrMissing Negative(gstabs+)
2334 Generate debug information in STABS format
2335
2336 gstabs+
2337 Common JoinedOrMissing Negative(gvms)
2338 Generate debug information in extended STABS format
2339
2340 gno-strict-dwarf
2341 Common RejectNegative Var(dwarf_strict,0) Init(0)
2342 Emit DWARF additions beyond selected version
2343
2344 gstrict-dwarf
2345 Common Report RejectNegative Var(dwarf_strict,1)
2346 Don't emit DWARF additions beyond selected version
2347
2348 gtoggle
2349 Common Report Var(flag_gtoggle)
2350 Toggle debug information generation
2351
2352 gvms
2353 Common JoinedOrMissing Negative(gxcoff)
2354 Generate debug information in VMS format
2355
2356 gxcoff
2357 Common JoinedOrMissing Negative(gxcoff+)
2358 Generate debug information in XCOFF format
2359
2360 gxcoff+
2361 Common JoinedOrMissing Negative(gcoff)
2362 Generate debug information in extended XCOFF format
2363
2364 h
2365 Driver Joined Separate
2366
2367 iplugindir=
2368 Common Joined Var(plugindir_string) Init(0)
2369 -iplugindir=<dir>       Set <dir> to be the default plugin directory
2370
2371 imultiarch
2372 Common Joined Separate RejectDriver Var(imultiarch) Init(0)
2373 -imultiarch <dir>       Set <dir> to be the multiarch include subdirectory
2374
2375 l
2376 Driver Joined Separate
2377
2378 n
2379 Driver
2380
2381 no-canonical-prefixes
2382 Driver
2383
2384 nodefaultlibs
2385 Driver
2386
2387 nostartfiles
2388 Driver
2389
2390 nostdlib
2391 Driver
2392
2393 o
2394 Common Driver Joined Separate Var(asm_file_name) MissingArgError(missing filename after %qs)
2395 -o <file>       Place output into <file>
2396
2397 p
2398 Common Var(profile_flag)
2399 Enable function profiling
2400
2401 pass-exit-codes
2402 Driver Var(pass_exit_codes)
2403
2404 pedantic
2405 Common Alias(Wpedantic)
2406
2407 pedantic-errors
2408 Common Var(flag_pedantic_errors)
2409 Like -pedantic but issue them as errors
2410
2411 pg
2412 Driver
2413
2414 pipe
2415 Driver Var(use_pipes)
2416
2417 print-file-name=
2418 Driver JoinedOrMissing Var(print_file_name)
2419
2420 print-libgcc-file-name
2421 Driver
2422
2423 print-multi-directory
2424 Driver Var(print_multi_directory)
2425
2426 print-multi-lib
2427 Driver Var(print_multi_lib)
2428
2429 print-multi-os-directory
2430 Driver Var(print_multi_os_directory)
2431
2432 print-multiarch
2433 Driver Var(print_multiarch)
2434
2435 print-prog-name=
2436 Driver JoinedOrMissing Var(print_prog_name)
2437
2438 print-search-dirs
2439 Driver Var(print_search_dirs)
2440
2441 print-sysroot
2442 Driver Var(print_sysroot)
2443
2444 print-sysroot-headers-suffix
2445 Driver Var(print_sysroot_headers_suffix)
2446
2447 quiet
2448 Common Var(quiet_flag) RejectDriver
2449 Do not display functions compiled or elapsed time
2450
2451 r
2452 Driver
2453
2454 s
2455 Driver
2456
2457 save-temps
2458 Driver
2459
2460 save-temps=
2461 Driver Joined
2462
2463 t
2464 Driver
2465
2466 time
2467 Driver Var(report_times)
2468
2469 time=
2470 Driver JoinedOrMissing
2471
2472 u
2473 Driver Joined Separate
2474
2475 undef
2476 Driver
2477 ; C option, but driver must not handle as "-u ndef".
2478
2479 v
2480 Common Driver Var(verbose_flag)
2481 Enable verbose output
2482
2483 version
2484 Common Var(version_flag) RejectDriver
2485 Display the compiler's version
2486
2487 w
2488 Common Var(inhibit_warnings)
2489 Suppress warnings
2490
2491 wrapper
2492 Driver Separate Var(wrapper_string)
2493
2494 x
2495 Driver Joined Separate
2496
2497 shared
2498 Driver RejectNegative Negative(pie)
2499 Create a shared library
2500
2501 shared-libgcc
2502 Driver
2503
2504 specs
2505 Driver Separate Alias(specs=)
2506
2507 specs=
2508 Driver Joined
2509
2510 static
2511 Driver
2512
2513 static-libgcc
2514 Driver
2515
2516 static-libgfortran
2517 Driver
2518 ; Documented for Fortran, but always accepted by driver.
2519
2520 static-libstdc++
2521 Driver
2522
2523 static-libgo
2524 Driver
2525 ; Documented for Go, but always accepted by driver.
2526
2527 static-libasan
2528 Driver
2529
2530 static-libtsan
2531 Driver
2532
2533 symbolic
2534 Driver
2535
2536 pie
2537 Driver RejectNegative Negative(shared)
2538 Create a position independent executable
2539
2540 z
2541 Driver Joined Separate
2542
2543 ; This comment is to ensure we retain the blank line above.