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
   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 ; 0 means straightforward implementation of complex divide acceptable.
  36 ; 1 means wide ranges of inputs must work for complex divide.
  37 ; 2 means C99-like requirements for complex multiply and divide.
  38 Variable
  39 int flag_complex_method = 1
  40
  41 ; Nonzero if subexpressions must be evaluated from left-to-right.
  42 Variable
  43 int flag_evaluation_order = 0
  44
  45 ; Set the default region and algorithm for the integrated register
  46 ; allocator.
  47
  48 Variable
  49 enum ira_algorithm flag_ira_algorithm = IRA_ALGORITHM_CB
  50
  51 Variable
  52 enum ira_region flag_ira_region = IRA_REGION_MIXED
  53
  54 ; Language specific warning pass for unused results.
  55 Variable
  56 bool flag_warn_unused_result = false
  57
  58 Variable
  59 int *param_values
  60
  61 ###
  62 Driver
  63
  64 -assemble
  65 Driver Alias(S)
  66
  67 -compile
  68 Driver Alias(c)
  69
  70 -coverage
  71 Driver Alias(coverage)
  72
  73 -debug
  74 Common Alias(g)
  75
  76 -dump
  77 Common Separate Alias(d)
  78
  79 -dump=
  80 Common Joined Alias(d)
  81
  82 -dumpbase
  83 Common Separate Alias(dumpbase)
  84
  85 -dumpdir
  86 Common Separate Alias(dumpdir)
  87
  88 -entry
  89 Driver Separate Alias(e)
  90
  91 -entry=
  92 Driver Joined Alias(e)
  93
  94 -extra-warnings
  95 Common Warning Alias(Wextra)
  96
  97 -for-assembler
  98 Driver Separate Alias(Xassembler)
  99
 100 -for-assembler=
 101 Driver JoinedOrMissing Alias(Xassembler)
 102
 103 -for-linker
 104 Driver Separate Alias(Xlinker)
 105
 106 -for-linker=
 107 Driver JoinedOrMissing Alias(Xlinker)
 108
 109 -force-link
 110 Driver Separate Alias(u)
 111
 112 -force-link=
 113 Driver Joined Alias(u)
 114
 115 -help
 116 Common Driver Var(help_flag)
 117 Display this information
 118
 119 -help=
 120 Common Driver Report Joined
 121 --help=<class>  Display descriptions of a specific class of options.  <class> is one or more of optimizers, target, warnings, undocumented, params
 122
 123 -language
 124 Driver Separate Alias(x)
 125
 126 -language=
 127 Driver Joined Alias(x)
 128
 129 -library-directory
 130 Driver Separate Alias(L)
 131
 132 -library-directory=
 133 Driver Joined Alias(L)
 134
 135 -no-canonical-prefixes
 136 Driver Alias(no-canonical-prefixes)
 137
 138 -no-standard-libraries
 139 Driver Alias(nostdlib)
 140
 141 -no-warnings
 142 Common Alias(w)
 143
 144 -optimize
 145 Common Alias(O)
 146
 147 -output
 148 Common Driver Separate Alias(o) MissingArgError(missing filename after %qs)
 149
 150 -output=
 151 Common Driver Joined Alias(o) MissingArgError(missing filename after %qs)
 152
 153 -pass-exit-codes
 154 Driver Alias(pass-exit-codes)
 155
 156 -pedantic
 157 Common Alias(pedantic)
 158
 159 -pedantic-errors
 160 Common Alias(pedantic-errors)
 161
 162 -pie
 163 Common Alias(pie)
 164
 165 -pipe
 166 Driver Alias(pipe)
 167
 168 -prefix
 169 Driver Separate Alias(B)
 170
 171 -prefix=
 172 Driver JoinedOrMissing Alias(B)
 173
 174 -preprocess
 175 Driver Alias(E)
 176
 177 -print-file-name
 178 Driver Separate Alias(print-file-name=)
 179
 180 -print-file-name=
 181 Driver JoinedOrMissing Alias(print-file-name=)
 182
 183 -print-libgcc-file-name
 184 Driver Alias(print-libgcc-file-name)
 185
 186 -print-multi-directory
 187 Driver Alias(print-multi-directory)
 188
 189 -print-multi-lib
 190 Driver Alias(print-multi-lib)
 191
 192 -print-multi-os-directory
 193 Driver Alias(print-multi-os-directory)
 194
 195 -print-prog-name
 196 Driver Separate Alias(print-prog-name=)
 197
 198 -print-prog-name=
 199 Driver JoinedOrMissing Alias(print-prog-name=)
 200
 201 -print-search-dirs
 202 Driver Alias(print-search-dirs)
 203
 204 -print-sysroot
 205 Driver Alias(print-sysroot)
 206
 207 -print-sysroot-headers-suffix
 208 Driver Alias(print-sysroot-headers-suffix)
 209
 210 -profile
 211 Common Alias(p)
 212
 213 -save-temps
 214 Driver Alias(save-temps)
 215
 216 -shared
 217 Common Alias(shared)
 218
 219 -specs
 220 Driver Separate Alias(specs=)
 221
 222 -specs=
 223 Driver Joined Alias(specs=)
 224
 225 -static
 226 Driver Alias(static)
 227
 228 -symbolic
 229 Driver Alias(symbolic)
 230
 231 -target-help
 232 Common Driver
 233 Alias for --help=target
 234
 235 -time
 236 Driver Alias(time)
 237
 238 -verbose
 239 Driver Alias(v)
 240
 241 ;; The driver used to convert options such as --help into forms such
 242 ;; as -fhelp; the following four entries are for compatibility with
 243 ;; any direct uses of those (undocumented) -f forms
 244 fhelp
 245 Common Driver Alias(-help)
 246
 247 fhelp=
 248 Common Driver Joined Alias(-help=)
 249
 250 ftarget-help
 251 Common Driver Alias(-target-help)
 252
 253 fversion
 254 Common Driver Alias(-version)
 255
 256 -param
 257 Common Separate
 258 --param <param>=<value> Set parameter <param> to value.  See below for a complete list of parameters
 259
 260 -param=
 261 Common Joined Alias(-param)
 262
 263 -sysroot
 264 Driver Separate Alias(-sysroot=)
 265
 266 -sysroot=
 267 Driver JoinedOrMissing
 268
 269 -version
 270 Common Driver
 271
 272 B
 273 Driver Joined Separate
 274
 275 E
 276 Driver
 277
 278 L
 279 Driver Joined Separate
 280
 281 O
 282 Common JoinedOrMissing Optimization
 283 -O<number>      Set optimization level to <number>
 284
 285 Os
 286 Common Optimization
 287 Optimize for space rather than speed
 288
 289 Ofast
 290 Common Optimization
 291 Optimize for speed disregarding exact standards compliance
 292
 293 S
 294 Driver
 295
 296 W
 297 Common RejectNegative Warning Alias(Wextra)
 298 This switch is deprecated; use -Wextra instead
 299
 300 Wa,
 301 Driver JoinedOrMissing
 302
 303 Wl,
 304 Driver JoinedOrMissing
 305
 306 Wp,
 307 Driver JoinedOrMissing
 308
 309 Waggregate-return
 310 Common Var(warn_aggregate_return) Warning
 311 Warn about returning structures, unions or arrays
 312
 313 Warray-bounds
 314 Common Var(warn_array_bounds) Warning
 315 Warn if an array is accessed out of bounds
 316
 317 Wattributes
 318 Common Var(warn_attributes) Init(1) Warning
 319 Warn about inappropriate attribute usage
 320
 321 Wcast-align
 322 Common Var(warn_cast_align) Warning
 323 Warn about pointer casts which increase alignment
 324
 325 Wcpp
 326 Common Var(warn_cpp) Init(1) Warning
 327 Warn when a #warning directive is encountered
 328
 329 Wdeprecated-declarations
 330 Common Var(warn_deprecated_decl) Init(1) Warning
 331 Warn about uses of __attribute__((deprecated)) declarations
 332
 333 Wdisabled-optimization
 334 Common Var(warn_disabled_optimization) Warning
 335 Warn when an optimization pass is disabled
 336
 337 Werror
 338 Common Var(warnings_are_errors)
 339 Treat all warnings as errors
 340
 341 Werror=
 342 Common Joined
 343 Treat specified warning as error
 344
 345 Wextra
 346 Common Var(extra_warnings) Warning
 347 Print extra (possibly unwanted) warnings
 348
 349 Wfatal-errors
 350 Common Var(flag_fatal_errors)
 351 Exit on the first error occurred
 352
 353 Wframe-larger-than=
 354 Common RejectNegative Joined UInteger
 355 -Wframe-larger-than=<number>    Warn if a function's stack frame requires more than <number> bytes
 356
 357 Winline
 358 Common Var(warn_inline) Warning
 359 Warn when an inlined function cannot be inlined
 360
 361 Wlarger-than-
 362 Common RejectNegative Joined Warning Undocumented Alias(Wlarger-than=)
 363
 364 Wlarger-than=
 365 Common RejectNegative Joined UInteger Warning
 366 -Wlarger-than=<number>  Warn if an object is larger than <number> bytes
 367
 368 Wunsafe-loop-optimizations
 369 Common Var(warn_unsafe_loop_optimizations) Warning
 370 Warn if the loop cannot be optimized due to nontrivial assumptions.
 371
 372 Wmissing-noreturn
 373 Common Var(warn_missing_noreturn) Warning
 374 Warn about functions which might be candidates for __attribute__((noreturn))
 375
 376 Wmudflap
 377 Common Var(warn_mudflap) Init(1) Warning
 378 Warn about constructs not instrumented by -fmudflap
 379
 380 Woverflow
 381 Common Var(warn_overflow) Init(1) Warning
 382 Warn about overflow in arithmetic expressions
 383
 384 Wpacked
 385 Common Var(warn_packed) Warning
 386 Warn when the packed attribute has no effect on struct layout
 387
 388 Wpadded
 389 Common Var(warn_padded) Warning
 390 Warn when padding is required to align structure members
 391
 392 Wshadow
 393 Common Var(warn_shadow) Warning
 394 Warn when one local variable shadows another
 395
 396 Wstack-protector
 397 Common Var(warn_stack_protect) Warning
 398 Warn when not issuing stack smashing protection for some reason
 399
 400 Wstrict-aliasing
 401 Common Warning
 402 Warn about code which might break strict aliasing rules
 403
 404 Wstrict-aliasing=
 405 Common Joined RejectNegative UInteger Var(warn_strict_aliasing) Init(-1) Warning
 406 Warn about code which might break strict aliasing rules
 407
 408 Wstrict-overflow
 409 Common Warning
 410 Warn about optimizations that assume that signed overflow is undefined
 411
 412 Wstrict-overflow=
 413 Common Joined RejectNegative UInteger Var(warn_strict_overflow) Init(-1) Warning
 414 Warn about optimizations that assume that signed overflow is undefined
 415
 416 Wsuggest-attribute=const
 417 Common Var(warn_suggest_attribute_const) Warning
 418 Warn about functions which might be candidates for __attribute__((const))
 419
 420 Wsuggest-attribute=pure
 421 Common Var(warn_suggest_attribute_pure) Warning
 422 Warn about functions which might be candidates for __attribute__((pure))
 423
 424 Wsuggest-attribute=noreturn
 425 Common Var(warn_suggest_attribute_noreturn) Warning
 426 Warn about functions which might be candidates for __attribute__((noreturn))
 427
 428 Wswitch
 429 Common Var(warn_switch) Warning
 430 Warn about enumerated switches, with no default, missing a case
 431
 432 Wswitch-default
 433 Common Var(warn_switch_default) Warning
 434 Warn about enumerated switches missing a \"default:\" statement
 435
 436 Wswitch-enum
 437 Common Var(warn_switch_enum) Warning
 438 Warn about all enumerated switches missing a specific case
 439
 440 Wsystem-headers
 441 Common Var(warn_system_headers) Warning
 442 Do not suppress warnings from system headers
 443
 444 Wtrampolines
 445 Common Var(warn_trampolines) Warning
 446 Warn whenever a trampoline is generated
 447
 448 Wtype-limits
 449 Common Var(warn_type_limits) Init(-1) Warning
 450 Warn if a comparison is always true or always false due to the limited range of the data type
 451
 452 Wuninitialized
 453 Common Var(warn_uninitialized) Init(-1) Warning
 454 Warn about uninitialized automatic variables
 455
 456 Wunreachable-code
 457 Common Ignore
 458 Does nothing. Preserved for backward compatibility.
 459
 460 Wunused
 461 Common Var(warn_unused) Init(0) Warning
 462 Enable all -Wunused- warnings
 463
 464 Wunused-but-set-parameter
 465 Common Var(warn_unused_but_set_parameter) Init(-1) Warning
 466 Warn when a function parameter is only set, otherwise unused
 467
 468 Wunused-but-set-variable
 469 Common Var(warn_unused_but_set_variable) Init(-1) Warning
 470 Warn when a variable is only set, otherwise unused
 471
 472 Wunused-function
 473 Common Var(warn_unused_function) Init(-1) Warning
 474 Warn when a function is unused
 475
 476 Wunused-label
 477 Common Var(warn_unused_label) Init(-1) Warning
 478 Warn when a label is unused
 479
 480 Wunused-parameter
 481 Common Var(warn_unused_parameter) Init(-1) Warning
 482 Warn when a function parameter is unused
 483
 484 Wunused-value
 485 Common Var(warn_unused_value) Init(-1) Warning
 486 Warn when an expression value is unused
 487
 488 Wunused-variable
 489 Common Var(warn_unused_variable) Init(-1) Warning
 490 Warn when a variable is unused
 491
 492 Wcoverage-mismatch
 493 Common Var(warn_coverage_mismatch) Init(1) Warning
 494 Warn in case profiles in -fprofile-use do not match
 495
 496 Xassembler
 497 Driver Separate
 498
 499 Xlinker
 500 Driver Separate
 501
 502 Xpreprocessor
 503 Driver Separate
 504
 505 aux-info
 506 Common Separate
 507 -aux-info <file>        Emit declaration information into <file>
 508
 509 aux-info=
 510 Common Joined Alias(aux-info)
 511
 512 auxbase
 513 Common Separate RejectDriver
 514
 515 auxbase-strip
 516 Common Separate RejectDriver
 517
 518 coverage
 519 Driver
 520
 521 c
 522 Driver
 523
 524 d
 525 Common Joined
 526 -d<letters>     Enable dumps from specific passes of the compiler
 527
 528 dumpbase
 529 Common Separate
 530 -dumpbase <file>        Set the file basename to be used for dumps
 531
 532 dumpdir
 533 Common Separate
 534 -dumpdir <dir>  Set the directory name to be used for dumps
 535
 536 dumpmachine
 537 Driver
 538
 539 dumpspecs
 540 Driver
 541
 542 dumpversion
 543 Driver
 544
 545 e
 546 Driver Joined Separate
 547
 548 ; The version of the C++ ABI in use.  The following values are allowed:
 549 ;
 550 ; 0: The version of the ABI believed most conformant with the C++ ABI
 551 ;    specification.  This ABI may change as bugs are discovered and fixed.
 552 ;    Therefore, 0 will not necessarily indicate the same ABI in different
 553 ;    versions of G++.
 554 ;
 555 ; 1: The version of the ABI first used in G++ 3.2.
 556 ;
 557 ; 2: The version of the ABI first used in G++ 3.4 (and current default).
 558 ;
 559 ; 3: The version of the ABI that fixes the missing underscore
 560 ;    in template non-type arguments of pointer type.
 561 ;
 562 ; 4: The version of the ABI that introduces unambiguous mangling of
 563 ;    vector types.
 564 ;
 565 ; Additional positive integers will be assigned as new versions of
 566 ; the ABI become the default version of the ABI.
 567 fabi-version=
 568 Common Joined RejectNegative UInteger Var(flag_abi_version) Init(2)
 569
 570 falign-functions
 571 Common Report Var(align_functions,0) Optimization UInteger
 572 Align the start of functions
 573
 574 falign-functions=
 575 Common RejectNegative Joined UInteger
 576
 577 falign-jumps
 578 Common Report Var(align_jumps,0) Optimization UInteger
 579 Align labels which are only reached by jumping
 580
 581 falign-jumps=
 582 Common RejectNegative Joined UInteger
 583
 584 falign-labels
 585 Common Report Var(align_labels,0) Optimization UInteger
 586 Align all labels
 587
 588 falign-labels=
 589 Common RejectNegative Joined UInteger
 590
 591 falign-loops
 592 Common Report Var(align_loops) Optimization UInteger
 593 Align the start of loops
 594
 595 falign-loops=
 596 Common RejectNegative Joined UInteger
 597
 598 fargument-alias
 599 Common Ignore
 600 Does nothing. Preserved for backward compatibility.
 601
 602 fargument-noalias
 603 Common Ignore
 604 Does nothing. Preserved for backward compatibility.
 605
 606 fargument-noalias-global
 607 Common Ignore
 608 Does nothing. Preserved for backward compatibility.
 609
 610 fargument-noalias-anything
 611 Common Ignore
 612 Does nothing. Preserved for backward compatibility.
 613
 614 fasynchronous-unwind-tables
 615 Common Report Var(flag_asynchronous_unwind_tables) Optimization
 616 Generate unwind tables that are exact at each instruction boundary
 617
 618 fauto-inc-dec
 619 Common Report Var(flag_auto_inc_dec) Init(1)
 620 Generate auto-inc/dec instructions
 621
 622 ; -fcheck-bounds causes gcc to generate array bounds checks.
 623 ; For C, C++ and ObjC: defaults off.
 624 ; For Java: defaults to on.
 625 ; For Fortran: defaults to off.
 626 fbounds-check
 627 Common Report Var(flag_bounds_check)
 628 Generate code to check bounds before indexing arrays
 629
 630 fbranch-count-reg
 631 Common Report Var(flag_branch_on_count_reg) Init(1) Optimization
 632 Replace add, compare, branch with branch on count register
 633
 634 fbranch-probabilities
 635 Common Report Var(flag_branch_probabilities) Optimization
 636 Use profiling information for branch probabilities
 637
 638 fbranch-target-load-optimize
 639 Common Report Var(flag_branch_target_load_optimize) Optimization
 640 Perform branch target load optimization before prologue / epilogue threading
 641
 642 fbranch-target-load-optimize2
 643 Common Report Var(flag_branch_target_load_optimize2) Optimization
 644 Perform branch target load optimization after prologue / epilogue threading
 645
 646 fbtr-bb-exclusive
 647 Common Report Var(flag_btr_bb_exclusive) Optimization
 648 Restrict target load migration not to re-use registers in any basic block
 649
 650 fcall-saved-
 651 Common Joined RejectNegative
 652 -fcall-saved-<register> Mark <register> as being preserved across functions
 653
 654 fcall-used-
 655 Common Joined RejectNegative
 656 -fcall-used-<register>  Mark <register> as being corrupted by function calls
 657
 658 ; Nonzero for -fcaller-saves: allocate values in regs that need to
 659 ; be saved across function calls, if that produces overall better code.
 660 ; Optional now, so people can test it.
 661 fcaller-saves
 662 Common Report Var(flag_caller_saves) Optimization
 663 Save registers around function calls
 664
 665 fcheck-data-deps
 666 Common Report Var(flag_check_data_deps)
 667 Compare the results of several data dependence analyzers.
 668
 669 fcombine-stack-adjustments
 670 Common Report Var(flag_combine_stack_adjustments) Optimization
 671 Looks for opportunities to reduce stack adjustments and stack references.
 672
 673 fcommon
 674 Common Report Var(flag_no_common,0) Optimization
 675 Do not put uninitialized globals in the common section
 676
 677 fcompare-debug
 678 Driver
 679 ; Converted by the driver to -fcompare-debug= options.
 680
 681 fcompare-debug=
 682 Common Driver JoinedOrMissing RejectNegative Var(flag_compare_debug_opt)
 683 -fcompare-debug[=<opts>]        Compile with and without e.g. -gtoggle, and compare the final-insns dump
 684
 685 fcompare-debug-second
 686 Common Driver RejectNegative
 687 Run only the second compilation of -fcompare-debug
 688
 689 fconserve-stack
 690 Common Var(flag_conserve_stack) Optimization
 691 Do not perform optimizations increasing noticeably stack usage
 692
 693 fcprop-registers
 694 Common Report Var(flag_cprop_registers) Optimization
 695 Perform a register copy-propagation optimization pass
 696
 697 fcrossjumping
 698 Common Report Var(flag_crossjumping) Optimization
 699 Perform cross-jumping optimization
 700
 701 fcse-follow-jumps
 702 Common Report Var(flag_cse_follow_jumps) Optimization
 703 When running CSE, follow jumps to their targets
 704
 705 fcse-skip-blocks
 706 Common Ignore
 707 Does nothing.  Preserved for backward compatibility.
 708
 709 fcx-limited-range
 710 Common Report Var(flag_cx_limited_range) Optimization
 711 Omit range reduction step when performing complex division
 712
 713 fcx-fortran-rules
 714 Common Report Var(flag_cx_fortran_rules) Optimization
 715 Complex multiplication and division follow Fortran rules
 716
 717 fdata-sections
 718 Common Report Var(flag_data_sections) Optimization
 719 Place data items into their own section
 720
 721 fdbg-cnt-list
 722 Common Report
 723 List all available debugging counters with their limits and counts.
 724
 725 fdbg-cnt=
 726 Common RejectNegative Joined
 727 -fdbg-cnt=<counter>:<limit>[,<counter>:<limit>,...]     Set the debug counter limit.
 728
 729 fdebug-prefix-map=
 730 Common Joined RejectNegative
 731 Map one directory name to another in debug information
 732
 733 ; Nonzero for -fdefer-pop: don't pop args after each function call
 734 ; instead save them up to pop many calls' args with one insns.
 735 fdefer-pop
 736 Common Report Var(flag_defer_pop) Optimization
 737 Defer popping functions args from stack until later
 738
 739 fdelayed-branch
 740 Common Report Var(flag_delayed_branch) Optimization
 741 Attempt to fill delay slots of branch instructions
 742
 743 fdelete-null-pointer-checks
 744 Common Report Var(flag_delete_null_pointer_checks) Init(1) Optimization
 745 Delete useless null pointer checks
 746
 747 fdiagnostics-show-location=
 748 Common Joined RejectNegative
 749 -fdiagnostics-show-location=[once|every-line]   How often to emit source location at the beginning of line-wrapped diagnostics
 750
 751 fdiagnostics-show-option
 752 Common Var(flag_diagnostics_show_option) Init(1)
 753 Amend appropriate diagnostic messages with the command line option that controls them
 754
 755 fdump-
 756 Common Joined RejectNegative
 757 -fdump-<type>   Dump various compiler internals to a file
 758
 759 fdump-final-insns
 760 Driver RejectNegative
 761
 762 fdump-final-insns=
 763 Common RejectNegative Joined Var(flag_dump_final_insns)
 764 -fdump-final-insns=filename     Dump to filename the insns at the end of translation
 765
 766 fdump-noaddr
 767 Common Report Var(flag_dump_noaddr)
 768 Suppress output of addresses in debugging dumps
 769
 770 fdump-unnumbered
 771 Common Report Var(flag_dump_unnumbered)
 772 Suppress output of instruction numbers, line number notes and addresses in debugging dumps
 773
 774 fdump-unnumbered-links
 775 Common Report Var(flag_dump_unnumbered_links)
 776 Suppress output of previous and next insn numbers in debugging dumps
 777
 778 fdwarf2-cfi-asm
 779 Common Report Var(flag_dwarf2_cfi_asm) Init(HAVE_GAS_CFI_DIRECTIVE)
 780 Enable CFI tables via GAS assembler directives.
 781
 782 fearly-inlining
 783 Common Report Var(flag_early_inlining) Init(1) Optimization
 784 Perform early inlining
 785
 786 feliminate-dwarf2-dups
 787 Common Report Var(flag_eliminate_dwarf2_dups)
 788 Perform DWARF2 duplicate elimination
 789
 790 fipa-sra
 791 Common Report Var(flag_ipa_sra) Init(0) Optimization
 792 Perform interprocedural reduction of aggregates
 793
 794 feliminate-unused-debug-symbols
 795 Common Report Var(flag_debug_only_used_symbols)
 796 Perform unused type elimination in debug info
 797
 798 feliminate-unused-debug-types
 799 Common Report Var(flag_eliminate_unused_debug_types) Init(1)
 800 Perform unused type elimination in debug info
 801
 802 femit-class-debug-always
 803 Common Report Var(flag_emit_class_debug_always) Init(0)
 804 Do not suppress C++ class debug information.
 805
 806 fenable-icf-debug
 807 Common Report Var(flag_enable_icf_debug)
 808 Generate debug information to support Identical Code Folding (ICF)
 809
 810 fexceptions
 811 Common Report Var(flag_exceptions) Optimization
 812 Enable exception handling
 813
 814 fexpensive-optimizations
 815 Common Report Var(flag_expensive_optimizations) Optimization
 816 Perform a number of minor, expensive optimizations
 817
 818 fexcess-precision=
 819 Common Joined RejectNegative
 820 -fexcess-precision=[fast|standard]      Specify handling of excess floating-point precision
 821
 822 ffast-math
 823 Common
 824
 825 ffinite-math-only
 826 Common Report Var(flag_finite_math_only) Optimization
 827 Assume no NaNs or infinities are generated
 828
 829 ffixed-
 830 Common Joined RejectNegative
 831 -ffixed-<register>      Mark <register> as being unavailable to the compiler
 832
 833 ffloat-store
 834 Common Report Var(flag_float_store) Optimization
 835 Don't allocate floats and doubles in extended-precision registers
 836
 837 fforce-addr
 838 Common Ignore
 839 Does nothing.  Preserved for backward compatibility.
 840
 841 fforward-propagate
 842 Common Report Var(flag_forward_propagate) Optimization
 843 Perform a forward propagation pass on RTL
 844
 845 ; Nonzero means don't put addresses of constant functions in registers.
 846 ; Used for compiling the Unix kernel, where strange substitutions are
 847 ; done on the assembly output.
 848 ffunction-cse
 849 Common Report Var(flag_no_function_cse,0)
 850 Allow function addresses to be held in registers
 851
 852 ffunction-sections
 853 Common Report Var(flag_function_sections)
 854 Place each function into its own section
 855
 856 fgcse
 857 Common Report Var(flag_gcse) Optimization
 858 Perform global common subexpression elimination
 859
 860 fgcse-lm
 861 Common Report Var(flag_gcse_lm) Init(1) Optimization
 862 Perform enhanced load motion during global common subexpression elimination
 863
 864 fgcse-sm
 865 Common Report Var(flag_gcse_sm) Init(0) Optimization
 866 Perform store motion after global common subexpression elimination
 867
 868 fgcse-las
 869 Common Report Var(flag_gcse_las) Init(0) Optimization
 870 Perform redundant load after store elimination in global common subexpression
 871 elimination
 872
 873 fgcse-after-reload
 874 Common Report Var(flag_gcse_after_reload) Optimization
 875 Perform global common subexpression elimination after register allocation
 876 has finished
 877
 878 ; This option is not documented yet as its semantics will change.
 879 fgraphite
 880 Common Report Var(flag_graphite)
 881 Enable in and out of Graphite representation
 882
 883 fgraphite-identity
 884 Common Report Var(flag_graphite_identity) Optimization
 885 Enable Graphite Identity transformation
 886
 887 floop-parallelize-all
 888 Common Report Var(flag_loop_parallelize_all) Optimization
 889 Mark all loops as parallel
 890
 891 floop-strip-mine
 892 Common Report Var(flag_loop_strip_mine) Optimization
 893 Enable Loop Strip Mining transformation
 894
 895 floop-interchange
 896 Common Report Var(flag_loop_interchange) Optimization
 897 Enable Loop Interchange transformation
 898
 899 floop-block
 900 Common Report Var(flag_loop_block) Optimization
 901 Enable Loop Blocking transformation
 902
 903 floop-flatten
 904 Common Report Var(flag_loop_flatten) Optimization
 905 Enable Loop Flattening transformation
 906
 907 fstrict-volatile-bitfields
 908 Common Report Var(flag_strict_volatile_bitfields) Init(-1)
 909 Force bitfield accesses to match their type width
 910
 911 fguess-branch-probability
 912 Common Report Var(flag_guess_branch_prob) Optimization
 913 Enable guessing of branch probabilities
 914
 915 ; Nonzero means ignore `#ident' directives.  0 means handle them.
 916 ; Generate position-independent code for executables if possible
 917 ; On SVR4 targets, it also controls whether or not to emit a
 918 ; string identifying the compiler.
 919 fident
 920 Common Report Var(flag_no_ident,0)
 921 Process #ident directives
 922
 923 fif-conversion
 924 Common Report Var(flag_if_conversion) Optimization
 925 Perform conversion of conditional jumps to branchless equivalents
 926
 927 fif-conversion2
 928 Common Report Var(flag_if_conversion2) Optimization
 929 Perform conversion of conditional jumps to conditional execution
 930
 931 ftree-loop-if-convert
 932 Common Report Var(flag_tree_loop_if_convert) Init(-1) Optimization
 933 Convert conditional jumps in innermost loops to branchless equivalents
 934
 935 ftree-loop-if-convert-stores
 936 Common Report Var(flag_tree_loop_if_convert_stores) Optimization
 937 Also if-convert conditional jumps containing memory writes
 938
 939 ; -finhibit-size-directive inhibits output of .size for ELF.
 940 ; This is used only for compiling crtstuff.c,
 941 ; and it may be extended to other effects
 942 ; needed for crtstuff.c on other systems.
 943 finhibit-size-directive
 944 Common Report Var(flag_inhibit_size_directive)
 945 Do not generate .size directives
 946
 947 findirect-inlining
 948 Common Report Var(flag_indirect_inlining)
 949 Perform indirect inlining
 950
 951 ; Nonzero means that functions declared `inline' will be treated
 952 ; as `static'.  Prevents generation of zillions of copies of unused
 953 ; static inline functions; instead, `inlines' are written out
 954 ; only when actually used.  Used in conjunction with -g.  Also
 955 ; does the right thing with #pragma interface.
 956 finline
 957 Common Report Var(flag_no_inline,0) Init(0)
 958 Pay attention to the \"inline\" keyword
 959
 960 finline-small-functions
 961 Common Report Var(flag_inline_small_functions) Optimization
 962 Integrate simple functions into their callers when code size is known to not growth
 963
 964 finline-functions
 965 Common Report Var(flag_inline_functions) Optimization
 966 Integrate simple functions into their callers
 967
 968 finline-functions-called-once
 969 Common Report Var(flag_inline_functions_called_once) Init(1) Optimization
 970 Integrate functions called once into their callers
 971
 972 finline-limit-
 973 Common RejectNegative Joined Alias(finline-limit=)
 974
 975 finline-limit=
 976 Common RejectNegative Joined UInteger
 977 -finline-limit=<number> Limit the size of inlined functions to <number>
 978
 979 finstrument-functions
 980 Common Report Var(flag_instrument_function_entry_exit)
 981 Instrument function entry and exit with profiling calls
 982
 983 finstrument-functions-exclude-function-list=
 984 Common RejectNegative Joined
 985 -finstrument-functions-exclude-function-list=name,...  Do not instrument listed functions
 986
 987 finstrument-functions-exclude-file-list=
 988 Common RejectNegative Joined
 989 -finstrument-functions-exclude-file-list=filename,...  Do not instrument functions listed in files
 990
 991 fipa-cp
 992 Common Report Var(flag_ipa_cp) Optimization
 993 Perform Interprocedural constant propagation
 994
 995 fipa-cp-clone
 996 Common Report Var(flag_ipa_cp_clone) Optimization
 997 Perform cloning to make Interprocedural constant propagation stronger
 998
 999 fipa-profile
1000 Common Report Var(flag_ipa_profile) Init(0) Optimization
1001 Perform interprocedural profile propagation
1002
1003 fipa-pta
1004 Common Report Var(flag_ipa_pta) Init(0) Optimization
1005 Perform interprocedural points-to analysis
1006
1007 fipa-pure-const
1008 Common Report Var(flag_ipa_pure_const) Init(0) Optimization
1009 Discover pure and const functions
1010
1011 fipa-reference
1012 Common Report Var(flag_ipa_reference) Init(0) Optimization
1013 Discover readonly and non addressable static variables
1014
1015 fipa-matrix-reorg
1016 Common Report Var(flag_ipa_matrix_reorg) Optimization
1017 Perform matrix layout flattening and transposing based
1018 on profiling information.
1019
1020 fipa-struct-reorg
1021 Common Report Var(flag_ipa_struct_reorg)
1022 Perform structure layout optimizations based
1023 on profiling information.
1024
1025 fira-algorithm=
1026 Common Joined RejectNegative
1027 -fira-algorithm=[CB|priority] Set the used IRA algorithm
1028
1029 fira-region=
1030 Common Joined RejectNegative
1031 -fira-region=[one|all|mixed] Set regions for IRA
1032
1033 fira-loop-pressure
1034 Common Report Var(flag_ira_loop_pressure)
1035 Use IRA based register pressure calculation
1036 in RTL loop optimizations.
1037
1038 fira-share-save-slots
1039 Common Report Var(flag_ira_share_save_slots) Init(1)
1040 Share slots for saving different hard registers.
1041
1042 fira-share-spill-slots
1043 Common Report Var(flag_ira_share_spill_slots) Init(1)
1044 Share stack slots for spilled pseudo-registers.
1045
1046 fira-verbose=
1047 Common RejectNegative Joined UInteger Var(flag_ira_verbose) Init(5)
1048 -fira-verbose=<number>  Control IRA's level of diagnostic messages.
1049
1050 fivopts
1051 Common Report Var(flag_ivopts) Init(1) Optimization
1052 Optimize induction variables on trees
1053
1054 fjump-tables
1055 Common Var(flag_jump_tables) Init(1) Optimization
1056 Use jump tables for sufficiently large switch statements
1057
1058 fkeep-inline-functions
1059 Common Report Var(flag_keep_inline_functions)
1060 Generate code for functions even if they are fully inlined
1061
1062 fkeep-static-consts
1063 Common Report Var(flag_keep_static_consts) Init(1)
1064 Emit static const variables even if they are not used
1065
1066 fleading-underscore
1067 Common Report Var(flag_leading_underscore) Init(-1)
1068 Give external symbols a leading underscore
1069
1070 floop-optimize
1071 Common Ignore
1072 Does nothing.  Preserved for backward compatibility.
1073
1074 flto
1075 Common Var(flag_lto)
1076 Enable link-time optimization.
1077
1078 flto-partition=1to1
1079 Common Var(flag_lto_partition_1to1)
1080 Partition functions and vars at linktime based on object files they originate from
1081
1082 flto-partition=balanced
1083 Common Var(flag_lto_partition_balanced)
1084 Partition functions and vars at linktime into approximately same sized buckets
1085
1086 ; The initial value of -1 comes from Z_DEFAULT_COMPRESSION in zlib.h.
1087 flto-compression-level=
1088 Common Joined RejectNegative UInteger Var(flag_lto_compression_level) Init(-1)
1089 -flto-compression-level=<number>        Use zlib compression level <number> for IL
1090
1091 flto-report
1092 Common Report Var(flag_lto_report) Init(0) Optimization
1093 Report various link-time optimization statistics
1094
1095 fmath-errno
1096 Common Report Var(flag_errno_math) Init(1) Optimization
1097 Set errno after built-in math functions
1098
1099 fmem-report
1100 Common Report Var(mem_report)
1101 Report on permanent memory allocation
1102
1103 ; This will attempt to merge constant section constants, if 1 only
1104 ; string constants and constants from constant pool, if 2 also constant
1105 ; variables.
1106 fmerge-all-constants
1107 Common Report Var(flag_merge_constants,2) Init(1) Optimization
1108 Attempt to merge identical constants and constant variables
1109
1110 fmerge-constants
1111 Common Report Var(flag_merge_constants,1) Optimization
1112 Attempt to merge identical constants across compilation units
1113
1114 fmerge-debug-strings
1115 Common Report Var(flag_merge_debug_strings) Init(1)
1116 Attempt to merge identical debug strings across compilation units
1117
1118 fmessage-length=
1119 Common RejectNegative Joined UInteger
1120 -fmessage-length=<number>       Limit diagnostics to <number> characters per line.  0 suppresses line-wrapping
1121
1122 fmodulo-sched
1123 Common Report Var(flag_modulo_sched) Optimization
1124 Perform SMS based modulo scheduling before the first scheduling pass
1125
1126 fmodulo-sched-allow-regmoves
1127 Common Report Var(flag_modulo_sched_allow_regmoves)
1128 Perform SMS based modulo scheduling with register moves allowed
1129
1130 fmove-loop-invariants
1131 Common Report Var(flag_move_loop_invariants) Init(1) Optimization
1132 Move loop invariant computations out of loops
1133
1134 fmudflap
1135 Common RejectNegative Report Var(flag_mudflap)
1136 Add mudflap bounds-checking instrumentation for single-threaded program
1137
1138 fmudflapth
1139 Common RejectNegative Report Var(flag_mudflap,2)
1140 Add mudflap bounds-checking instrumentation for multi-threaded program
1141
1142 fmudflapir
1143 Common RejectNegative Report Var(flag_mudflap_ignore_reads)
1144 Ignore read operations when inserting mudflap instrumentation
1145
1146 fdce
1147 Common Var(flag_dce) Init(1) Optimization
1148 Use the RTL dead code elimination pass
1149
1150 fdse
1151 Common Var(flag_dse) Init(1) Optimization
1152 Use the RTL dead store elimination pass
1153
1154 freschedule-modulo-scheduled-loops
1155 Common Report Var(flag_resched_modulo_sched) Optimization
1156 Enable/Disable the traditional scheduling in loops that already passed modulo scheduling
1157
1158 fnon-call-exceptions
1159 Common Report Var(flag_non_call_exceptions) Optimization
1160 Support synchronous non-call exceptions
1161
1162 fomit-frame-pointer
1163 Common Report Var(flag_omit_frame_pointer) Optimization
1164 When possible do not generate stack frames
1165
1166 foptimize-register-move
1167 Common Report Var(flag_regmove) Optimization
1168 Do the full register move optimization pass
1169
1170 foptimize-sibling-calls
1171 Common Report Var(flag_optimize_sibling_calls) Optimization
1172 Optimize sibling and tail recursive calls
1173
1174 fpartial-inlining
1175 Common Report Var(flag_partial_inlining)
1176 Perform partial inlining
1177
1178 fpre-ipa-mem-report
1179 Common Report Var(pre_ipa_mem_report)
1180 Report on memory allocation before interprocedural optimization
1181
1182 fpost-ipa-mem-report
1183 Common Report Var(post_ipa_mem_report)
1184 Report on memory allocation before interprocedural optimization
1185
1186 fpack-struct
1187 Common Report Var(flag_pack_struct) Optimization
1188 Pack structure members together without holes
1189
1190 fpack-struct=
1191 Common RejectNegative Joined UInteger Optimization
1192 -fpack-struct=<number>  Set initial maximum structure member alignment
1193
1194 fpcc-struct-return
1195 Common Report Var(flag_pcc_struct_return,1) Init(DEFAULT_PCC_STRUCT_RETURN)
1196 Return small aggregates in memory, not registers
1197
1198 fpeel-loops
1199 Common Report Var(flag_peel_loops) Optimization
1200 Perform loop peeling
1201
1202 fpeephole
1203 Common Report Var(flag_no_peephole,0) Optimization
1204 Enable machine specific peephole optimizations
1205
1206 fpeephole2
1207 Common Report Var(flag_peephole2) Optimization
1208 Enable an RTL peephole pass before sched2
1209
1210 fPIC
1211 Common Report Var(flag_pic,2)
1212 Generate position-independent code if possible (large mode)
1213
1214 fPIE
1215 Common Report Var(flag_pie,2)
1216 Generate position-independent code for executables if possible (large mode)
1217
1218 fpic
1219 Common Report Var(flag_pic,1)
1220 Generate position-independent code if possible (small mode)
1221
1222 fpie
1223 Common Report Var(flag_pie,1)
1224 Generate position-independent code for executables if possible (small mode)
1225
1226 fplugin=
1227 Common Joined RejectNegative
1228 Specify a plugin to load
1229
1230 fplugin-arg-
1231 Common Joined RejectNegative
1232 -fplugin-arg-<name>-<key>[=<value>]     Specify argument <key>=<value> for plugin <name>
1233
1234 fpredictive-commoning
1235 Common Report Var(flag_predictive_commoning) Optimization
1236 Run predictive commoning optimization.
1237
1238 fprefetch-loop-arrays
1239 Common Report Var(flag_prefetch_loop_arrays) Init(-1) Optimization
1240 Generate prefetch instructions, if available, for arrays in loops
1241
1242 fprofile
1243 Common Report Var(profile_flag)
1244 Enable basic program profiling code
1245
1246 fprofile-arcs
1247 Common Report Var(profile_arc_flag)
1248 Insert arc-based program profiling code
1249
1250 fprofile-dir=
1251 Common Joined RejectNegative
1252 Set the top-level directory for storing the profile data.
1253 The default is 'pwd'.
1254
1255 fprofile-correction
1256 Common Report Var(flag_profile_correction)
1257 Enable correction of flow inconsistent profile data input
1258
1259 fprofile-generate
1260 Common
1261 Enable common options for generating profile info for profile feedback directed optimizations
1262
1263 fprofile-generate=
1264 Common Joined RejectNegative
1265 Enable common options for generating profile info for profile feedback directed optimizations, and set -fprofile-dir=
1266
1267 fprofile-use
1268 Common Var(flag_profile_use)
1269 Enable common options for performing profile feedback directed optimizations
1270
1271 fprofile-use=
1272 Common Joined RejectNegative
1273 Enable common options for performing profile feedback directed optimizations, and set -fprofile-dir=
1274
1275 fprofile-values
1276 Common Report Var(flag_profile_values)
1277 Insert code to profile values of expressions
1278
1279 frandom-seed
1280 Common
1281
1282 frandom-seed=
1283 Common Joined RejectNegative
1284 -frandom-seed=<string>  Make compile reproducible using <string>
1285
1286 ; This switch causes the command line that was used to create an
1287 ; object file to be recorded into the object file.  The exact format
1288 ; of this recording is target and binary file format dependent.
1289 ; It is related to the -fverbose-asm switch, but that switch only
1290 ; records information in the assembler output file as comments, so
1291 ; they never reach the object file.
1292 frecord-gcc-switches
1293 Common Report Var(flag_record_gcc_switches)
1294 Record gcc command line switches in the object file.
1295
1296 freg-struct-return
1297 Common Report Var(flag_pcc_struct_return,0) Optimization
1298 Return small aggregates in registers
1299
1300 fregmove
1301 Common Report Var(flag_regmove) Optimization
1302 Enables a register move optimization
1303
1304 frename-registers
1305 Common Report Var(flag_rename_registers) Init(2) Optimization
1306 Perform a register renaming optimization pass
1307
1308 freorder-blocks
1309 Common Report Var(flag_reorder_blocks) Optimization
1310 Reorder basic blocks to improve code placement
1311
1312 freorder-blocks-and-partition
1313 Common Report Var(flag_reorder_blocks_and_partition) Optimization
1314 Reorder basic blocks and partition into hot and cold sections
1315
1316 freorder-functions
1317 Common Report Var(flag_reorder_functions) Optimization
1318 Reorder functions to improve code placement
1319
1320 frerun-cse-after-loop
1321 Common Report Var(flag_rerun_cse_after_loop) Init(2) Optimization
1322 Add a common subexpression elimination pass after loop optimizations
1323
1324 frerun-loop-opt
1325 Common Ignore
1326 Does nothing.  Preserved for backward compatibility.
1327
1328 frounding-math
1329 Common Report Var(flag_rounding_math) Optimization
1330 Disable optimizations that assume default FP rounding behavior
1331
1332 fsched-interblock
1333 Common Report Var(flag_schedule_interblock) Init(1) Optimization
1334 Enable scheduling across basic blocks
1335
1336 fsched-pressure
1337 Common Report Var(flag_sched_pressure) Init(0) Optimization
1338 Enable register pressure sensitive insn scheduling
1339
1340 fsched-spec
1341 Common Report Var(flag_schedule_speculative) Init(1) Optimization
1342 Allow speculative motion of non-loads
1343
1344 fsched-spec-load
1345 Common Report Var(flag_schedule_speculative_load) Optimization
1346 Allow speculative motion of some loads
1347
1348 fsched-spec-load-dangerous
1349 Common Report Var(flag_schedule_speculative_load_dangerous) Optimization
1350 Allow speculative motion of more loads
1351
1352 fsched-verbose=
1353 Common RejectNegative Joined
1354 -fsched-verbose=<number>        Set the verbosity level of the scheduler
1355
1356 fsched2-use-superblocks
1357 Common Report Var(flag_sched2_use_superblocks) Optimization
1358 If scheduling post reload, do superblock scheduling
1359
1360 fsched2-use-traces
1361 Common Ignore
1362 Does nothing.  Preserved for backward compatibility.
1363
1364 fschedule-insns
1365 Common Report Var(flag_schedule_insns) Optimization
1366 Reschedule instructions before register allocation
1367
1368 fschedule-insns2
1369 Common Report Var(flag_schedule_insns_after_reload) Optimization
1370 Reschedule instructions after register allocation
1371
1372 ; This flag should be on when a target implements non-trivial
1373 ; scheduling hooks, maybe saving some information for its own sake.
1374 ; On IA64, for example, this is used for correct bundling.
1375 fselective-scheduling
1376 Common Report Var(flag_selective_scheduling) Optimization
1377 Schedule instructions using selective scheduling algorithm
1378
1379 fselective-scheduling2
1380 Common Report Var(flag_selective_scheduling2) Optimization
1381 Run selective scheduling after reload
1382
1383 fsel-sched-pipelining
1384 Common Report Var(flag_sel_sched_pipelining) Init(0) Optimization
1385 Perform software pipelining of inner loops during selective scheduling
1386
1387 fsel-sched-pipelining-outer-loops
1388 Common Report Var(flag_sel_sched_pipelining_outer_loops) Init(0) Optimization
1389 Perform software pipelining of outer loops during selective scheduling
1390
1391 fsel-sched-reschedule-pipelined
1392 Common Report Var(flag_sel_sched_reschedule_pipelined) Init(0) Optimization
1393 Reschedule pipelined regions without pipelining
1394
1395 ; sched_stalled_insns means that insns can be moved prematurely from the queue
1396 ; of stalled insns into the ready list.
1397 fsched-stalled-insns
1398 Common Report Var(flag_sched_stalled_insns) Optimization UInteger
1399 Allow premature scheduling of queued insns
1400
1401 fsched-stalled-insns=
1402 Common RejectNegative Joined UInteger
1403 -fsched-stalled-insns=<number>  Set number of queued insns that can be prematurely scheduled
1404
1405 ; sched_stalled_insns_dep controls how many recently scheduled cycles will
1406 ; be examined for a dependency on a stalled insn that is candidate for
1407 ; premature removal from the queue of stalled insns into the ready list (has
1408 ; an effect only if the flag 'sched_stalled_insns' is set).
1409 fsched-stalled-insns-dep
1410 Common Report Var(flag_sched_stalled_insns_dep,1) Init(1) Optimization UInteger
1411 Set dependence distance checking in premature scheduling of queued insns
1412
1413 fsched-stalled-insns-dep=
1414 Common RejectNegative Joined UInteger
1415 -fsched-stalled-insns-dep=<number>      Set dependence distance checking in premature scheduling of queued insns
1416
1417 fsched-group-heuristic
1418 Common Report Var(flag_sched_group_heuristic) Init(1) Optimization
1419 Enable the group heuristic in the scheduler
1420
1421 fsched-critical-path-heuristic
1422 Common Report Var(flag_sched_critical_path_heuristic) Init(1) Optimization
1423 Enable the critical path heuristic in the scheduler
1424
1425 fsched-spec-insn-heuristic
1426 Common Report Var(flag_sched_spec_insn_heuristic) Init(1) Optimization
1427 Enable the speculative instruction heuristic in the scheduler
1428
1429 fsched-rank-heuristic
1430 Common Report Var(flag_sched_rank_heuristic) Init(1) Optimization
1431 Enable the rank heuristic in the scheduler
1432
1433 fsched-last-insn-heuristic
1434 Common Report Var(flag_sched_last_insn_heuristic) Init(1) Optimization
1435 Enable the last instruction heuristic in the scheduler
1436
1437 fsched-dep-count-heuristic
1438 Common Report Var(flag_sched_dep_count_heuristic) Init(1) Optimization
1439 Enable the dependent count heuristic in the scheduler
1440
1441 fsection-anchors
1442 Common Report Var(flag_section_anchors) Optimization
1443 Access data in the same section from shared anchor points
1444
1445 fsee
1446 Common Ignore
1447 Does nothing.  Preserved for backward compatibility.
1448
1449 fzee
1450 Common Report Var(flag_zee) Init(0)
1451 Eliminate redundant zero extensions on targets that support implicit extensions.
1452
1453 fshow-column
1454 Common Report Var(flag_show_column) Init(1)
1455 Show column numbers in diagnostics, when available.  Default on
1456
1457 fsignaling-nans
1458 Common Report Var(flag_signaling_nans) Optimization
1459 Disable optimizations observable by IEEE signaling NaNs
1460
1461 fsigned-zeros
1462 Common Report Var(flag_signed_zeros) Init(1) Optimization
1463 Disable floating point optimizations that ignore the IEEE signedness of zero
1464
1465 fsingle-precision-constant
1466 Common Report Var(flag_single_precision_constant) Optimization
1467 Convert floating point constants to single precision constants
1468
1469 fsplit-ivs-in-unroller
1470 Common Report Var(flag_split_ivs_in_unroller) Init(1) Optimization
1471 Split lifetimes of induction variables when loops are unrolled
1472
1473 fsplit-stack
1474 Common Report Var(flag_split_stack) Init(-1)
1475 Generate discontiguous stack frames
1476
1477 fsplit-wide-types
1478 Common Report Var(flag_split_wide_types) Optimization
1479 Split wide types into independent registers
1480
1481 fvariable-expansion-in-unroller
1482 Common Report Var(flag_variable_expansion_in_unroller) Optimization
1483 Apply variable expansion when loops are unrolled
1484
1485 fstack-check=
1486 Common Report RejectNegative Joined
1487 -fstack-check=[no|generic|specific]     Insert stack checking code into the program
1488
1489 fstack-check
1490 Common Alias(fstack-check=, specific, no)
1491 Insert stack checking code into the program.  Same as -fstack-check=specific
1492
1493 fstack-limit
1494 Common
1495
1496 fstack-limit-register=
1497 Common RejectNegative Joined
1498 -fstack-limit-register=<register>       Trap if the stack goes past <register>
1499
1500 fstack-limit-symbol=
1501 Common RejectNegative Joined
1502 -fstack-limit-symbol=<name>     Trap if the stack goes past symbol <name>
1503
1504 fstack-protector
1505 Common Report Var(flag_stack_protect, 1)
1506 Use propolice as a stack protection method
1507
1508 fstack-protector-all
1509 Common Report RejectNegative Var(flag_stack_protect, 2)
1510 Use a stack protection method for every function
1511
1512 fstack-usage
1513 Common RejectNegative Var(flag_stack_usage)
1514 Output stack usage information on a per-function basis
1515
1516 fstrength-reduce
1517 Common Ignore
1518 Does nothing.  Preserved for backward compatibility.
1519
1520 ; Nonzero if we should do (language-dependent) alias analysis.
1521 ; Typically, this analysis will assume that expressions of certain
1522 ; types do not alias expressions of certain other types.  Only used
1523 ; if alias analysis (in general) is enabled.
1524 fstrict-aliasing
1525 Common Report Var(flag_strict_aliasing) Optimization
1526 Assume strict aliasing rules apply
1527
1528 fstrict-overflow
1529 Common Report Var(flag_strict_overflow)
1530 Treat signed overflow as undefined
1531
1532 fsyntax-only
1533 Common Report Var(flag_syntax_only)
1534 Check for syntax errors, then stop
1535
1536 ftest-coverage
1537 Common Report Var(flag_test_coverage)
1538 Create data files needed by \"gcov\"
1539
1540 fthread-jumps
1541 Common Report Var(flag_thread_jumps) Optimization
1542 Perform jump threading optimizations
1543
1544 ftime-report
1545 Common Report Var(time_report)
1546 Report the time taken by each compiler pass
1547
1548 ftls-model=
1549 Common Joined RejectNegative
1550 -ftls-model=[global-dynamic|local-dynamic|initial-exec|local-exec]      Set the default thread-local storage code generation model
1551
1552 ftoplevel-reorder
1553 Common Report Var(flag_toplevel_reorder) Init(2) Optimization
1554 Reorder top level functions, variables, and asms
1555
1556 ftracer
1557 Common Report Var(flag_tracer)
1558 Perform superblock formation via tail duplication
1559
1560 ; Zero means that floating-point math operations cannot generate a
1561 ; (user-visible) trap.  This is the case, for example, in nonstop
1562 ; IEEE 754 arithmetic.
1563 ftrapping-math
1564 Common Report Var(flag_trapping_math) Init(1) Optimization
1565 Assume floating-point operations can trap
1566
1567 ftrapv
1568 Common Report Var(flag_trapv) Optimization
1569 Trap for signed overflow in addition, subtraction and multiplication
1570
1571 ftree-ccp
1572 Common Report Var(flag_tree_ccp) Optimization
1573 Enable SSA-CCP optimization on trees
1574
1575 ftree-bit-ccp
1576 Common Report Var(flag_tree_bit_ccp) Optimization
1577 Enable SSA-BIT-CCP optimization on trees
1578
1579 ftree-store-ccp
1580 Common Ignore
1581 Does nothing.  Preserved for backward compatibility.
1582
1583 ftree-ch
1584 Common Report Var(flag_tree_ch) Optimization
1585 Enable loop header copying on trees
1586
1587 ftree-copyrename
1588 Common Report Var(flag_tree_copyrename) Optimization
1589 Replace SSA temporaries with better names in copies
1590
1591 ftree-copy-prop
1592 Common Report Var(flag_tree_copy_prop) Optimization
1593 Enable copy propagation on trees
1594
1595 ftree-store-copy-prop
1596 Common Ignore
1597 Does nothing.  Preserved for backward compatibility.
1598
1599 ftree-cselim
1600 Common Report Var(flag_tree_cselim) Init(2) Optimization
1601 Transform condition stores into unconditional ones
1602
1603 ftree-switch-conversion
1604 Common Report Var(flag_tree_switch_conversion) Optimization
1605 Perform conversions of switch initializations.
1606
1607 ftree-dce
1608 Common Report Var(flag_tree_dce) Optimization
1609 Enable SSA dead code elimination optimization on trees
1610
1611 ftree-dominator-opts
1612 Common Report Var(flag_tree_dom) Optimization
1613 Enable dominator optimizations
1614
1615 ftree-dse
1616 Common Report Var(flag_tree_dse) Optimization
1617 Enable dead store elimination
1618
1619 ftree-forwprop
1620 Common Report Var(flag_tree_forwprop) Init(1) Optimization
1621 Enable forward propagation on trees
1622
1623 ftree-fre
1624 Common Report Var(flag_tree_fre) Optimization
1625 Enable Full Redundancy Elimination (FRE) on trees
1626
1627 ftree-loop-distribution
1628 Common Report Var(flag_tree_loop_distribution) Optimization
1629 Enable loop distribution on trees
1630
1631 ftree-loop-distribute-patterns
1632 Common Report Var(flag_tree_loop_distribute_patterns) Optimization
1633 Enable loop distribution for patterns transformed into a library call
1634
1635 ftree-loop-im
1636 Common Report Var(flag_tree_loop_im) Init(1) Optimization
1637 Enable loop invariant motion on trees
1638
1639 ftree-loop-linear
1640 Common Report Var(flag_tree_loop_linear) Optimization
1641 Enable linear loop transforms on trees
1642
1643 ftree-loop-ivcanon
1644 Common Report Var(flag_tree_loop_ivcanon) Init(1) Optimization
1645 Create canonical induction variables in loops
1646
1647 ftree-loop-optimize
1648 Common Report Var(flag_tree_loop_optimize) Init(1) Optimization
1649 Enable loop optimizations on tree level
1650
1651 ftree-parallelize-loops=
1652 Common Report Joined RejectNegative UInteger Var(flag_tree_parallelize_loops) Init(1)
1653 Enable automatic parallelization of loops
1654
1655 ftree-phiprop
1656 Common Report Var(flag_tree_phiprop) Init(1) Optimization
1657 Enable hoisting loads from conditional pointers.
1658
1659 ftree-pre
1660 Common Report Var(flag_tree_pre) Optimization
1661 Enable SSA-PRE optimization on trees
1662
1663 ftree-pta
1664 Common Report Var(flag_tree_pta) Init(1) Optimization
1665 Perform function-local points-to analysis on trees.
1666
1667 ftree-reassoc
1668 Common Report Var(flag_tree_reassoc) Init(1) Optimization
1669 Enable reassociation on tree level
1670
1671 ftree-salias
1672 Common Ignore
1673 Does nothing.  Preserved for backward compatibility.
1674
1675 ftree-sink
1676 Common Report Var(flag_tree_sink) Optimization
1677 Enable SSA code sinking on trees
1678
1679 ftree-sra
1680 Common Report Var(flag_tree_sra) Optimization
1681 Perform scalar replacement of aggregates
1682
1683 ftree-ter
1684 Common Report Var(flag_tree_ter) Init(1) Optimization
1685 Replace temporary expressions in the SSA->normal pass
1686
1687 ftree-lrs
1688 Common Report Var(flag_tree_live_range_split) Optimization
1689 Perform live range splitting during the SSA->normal pass
1690
1691 ftree-vrp
1692 Common Report Var(flag_tree_vrp) Init(0) Optimization
1693 Perform Value Range Propagation on trees
1694
1695 funit-at-a-time
1696 Common Report Var(flag_unit_at_a_time) Init(1) Optimization
1697 Compile whole compilation unit at a time
1698
1699 funroll-loops
1700 Common Report Var(flag_unroll_loops) Optimization
1701 Perform loop unrolling when iteration count is known
1702
1703 funroll-all-loops
1704 Common Report Var(flag_unroll_all_loops) Optimization
1705 Perform loop unrolling for all loops
1706
1707 ; Nonzero means that loop optimizer may assume that the induction variables
1708 ; that control loops do not overflow and that the loops with nontrivial
1709 ; exit condition are not infinite
1710 funsafe-loop-optimizations
1711 Common Report Var(flag_unsafe_loop_optimizations) Optimization
1712 Allow loop optimizations to assume that the loops behave in normal way
1713
1714 fassociative-math
1715 Common Report Var(flag_associative_math)
1716 Allow optimization for floating-point arithmetic which may change the
1717 result of the operation due to rounding.
1718
1719 freciprocal-math
1720 Common Report Var(flag_reciprocal_math)
1721 Same as -fassociative-math for expressions which include division.
1722
1723 ; Nonzero means that unsafe floating-point math optimizations are allowed
1724 ; for the sake of speed.  IEEE compliance is not guaranteed, and operations
1725 ; are allowed to assume that their arguments and results are "normal"
1726 ; (e.g., nonnegative for SQRT).
1727 funsafe-math-optimizations
1728 Common Report Var(flag_unsafe_math_optimizations) Optimization
1729 Allow math optimizations that may violate IEEE or ISO standards
1730
1731 funswitch-loops
1732 Common Report Var(flag_unswitch_loops) Optimization
1733 Perform loop unswitching
1734
1735 funwind-tables
1736 Common Report Var(flag_unwind_tables) Optimization
1737 Just generate unwind tables for exception handling
1738
1739 fuse-linker-plugin
1740 Common Undocumented
1741
1742 ; Positive if we should track variables, negative if we should run
1743 ; the var-tracking pass only to discard debug annotations, zero if
1744 ; we're not to run it.  When flag_var_tracking == 2 (AUTODETECT_VALUE) it
1745 ; will be set according to optimize, debug_info_level and debug_hooks
1746 ; in process_options ().
1747 fvar-tracking
1748 Common Report Var(flag_var_tracking) Init(2) Optimization
1749 Perform variable tracking
1750
1751 ; Positive if we should track variables at assignments, negative if
1752 ; we should run the var-tracking pass only to discard debug
1753 ; annotations.  When flag_var_tracking_assignments ==
1754 ; AUTODETECT_VALUE it will be set according to flag_var_tracking.
1755 fvar-tracking-assignments
1756 Common Report Var(flag_var_tracking_assignments) Init(2) Optimization
1757 Perform variable tracking by annotating assignments
1758
1759 ; Nonzero if we should toggle flag_var_tracking_assignments after
1760 ; processing options and computing its default.  */
1761 fvar-tracking-assignments-toggle
1762 Common Report Var(flag_var_tracking_assignments_toggle) Optimization
1763 Toggle -fvar-tracking-assignments
1764
1765 fvar-tracking-uninit
1766 Common Report Var(flag_var_tracking_uninit) Optimization
1767 Perform variable tracking and also tag variables that are uninitialized
1768
1769 ftree-vectorize
1770 Common Report Var(flag_tree_vectorize) Optimization
1771 Enable loop vectorization on trees
1772
1773 ftree-slp-vectorize
1774 Common Report Var(flag_tree_slp_vectorize) Init(2) Optimization
1775 Enable basic block vectorization (SLP) on trees
1776
1777 fvect-cost-model
1778 Common Report Var(flag_vect_cost_model) Optimization
1779 Enable use of cost model in vectorization
1780
1781 ftree-vect-loop-version
1782 Common Report Var(flag_tree_vect_loop_version) Init(1) Optimization
1783 Enable loop versioning when doing loop vectorization on trees
1784
1785 ftree-vectorizer-verbose=
1786 Common RejectNegative Joined
1787 -ftree-vectorizer-verbose=<number>      Set the verbosity level of the vectorizer
1788
1789 ftree-scev-cprop
1790 Common Report Var(flag_tree_scev_cprop) Init(1) Optimization
1791 Enable copy propagation of scalar-evolution information.
1792
1793 ; -fverbose-asm causes extra commentary information to be produced in
1794 ; the generated assembly code (to make it more readable).  This option
1795 ; is generally only of use to those who actually need to read the
1796 ; generated assembly code (perhaps while debugging the compiler itself).
1797 ; -fno-verbose-asm, the default, causes the extra information
1798 ; to not be added and is useful when comparing two assembler files.
1799 fverbose-asm
1800 Common Report Var(flag_verbose_asm)
1801 Add extra commentary to assembler output
1802
1803 fvisibility=
1804 Common Joined RejectNegative
1805 -fvisibility=[default|internal|hidden|protected]        Set the default symbol visibility
1806
1807
1808 fvpt
1809 Common Report Var(flag_value_profile_transformations) Optimization
1810 Use expression value profiles in optimizations
1811
1812 fweb
1813 Common Report Var(flag_web) Init(2) Optimization
1814 Construct webs and split unrelated uses of single variable
1815
1816 fwhopr
1817 Common
1818 Enable partitioned link-time optimization
1819
1820 fwhopr=
1821 Common RejectNegative Joined Var(flag_whopr)
1822 Partitioned link-time optimization with number of parallel jobs or jobserver.
1823
1824 ftree-builtin-call-dce
1825 Common Report Var(flag_tree_builtin_call_dce) Init(0) Optimization
1826 Enable conditional dead code elimination for builtin calls
1827
1828 fwhole-program
1829 Common Report Var(flag_whole_program) Init(0) Optimization
1830 Perform whole program optimizations
1831
1832 fwrapv
1833 Common Report Var(flag_wrapv) Optimization
1834 Assume signed arithmetic overflow wraps around
1835
1836 fzero-initialized-in-bss
1837 Common Report Var(flag_zero_initialized_in_bss) Init(1)
1838 Put zero initialized data in the bss section
1839
1840 g
1841 Common JoinedOrMissing
1842 Generate debug information in default format
1843
1844 gcoff
1845 Common JoinedOrMissing Negative(gdwarf-)
1846 Generate debug information in COFF format
1847
1848 gdwarf-
1849 Common Joined UInteger Var(dwarf_version) Init(2) Negative(gstabs)
1850 Generate debug information in DWARF v2 (or later) format
1851
1852 ggdb
1853 Common JoinedOrMissing
1854 Generate debug information in default extended format
1855
1856 gstabs
1857 Common JoinedOrMissing Negative(gstabs+)
1858 Generate debug information in STABS format
1859
1860 gstabs+
1861 Common JoinedOrMissing Negative(gvms)
1862 Generate debug information in extended STABS format
1863
1864 gno-strict-dwarf
1865 Common RejectNegative Var(dwarf_strict,0) Init(-1)
1866 Emit DWARF additions beyond selected version
1867
1868 gstrict-dwarf
1869 Common Report RejectNegative Var(dwarf_strict,1)
1870 Don't emit DWARF additions beyond selected version
1871
1872 gtoggle
1873 Common Report Var(flag_gtoggle)
1874 Toggle debug information generation
1875
1876 gvms
1877 Common JoinedOrMissing Negative(gxcoff)
1878 Generate debug information in VMS format
1879
1880 gxcoff
1881 Common JoinedOrMissing Negative(gxcoff+)
1882 Generate debug information in XCOFF format
1883
1884 gxcoff+
1885 Common JoinedOrMissing Negative(gcoff)
1886 Generate debug information in extended XCOFF format
1887
1888 iplugindir=
1889 Common Joined Var(plugindir_string) Init(0)
1890 -iplugindir=<dir>       Set <dir> to be the default plugin directory
1891
1892 l
1893 Driver Joined Separate
1894
1895 no-canonical-prefixes
1896 Driver
1897
1898 nodefaultlibs
1899 Driver
1900
1901 nostdlib
1902 Driver
1903
1904 o
1905 Common Driver Joined Separate MissingArgError(missing filename after %qs)
1906 -o <file>       Place output into <file>
1907
1908 p
1909 Common Var(profile_flag)
1910 Enable function profiling
1911
1912 pass-exit-codes
1913 Driver Var(pass_exit_codes)
1914
1915 pedantic
1916 Common Var(pedantic)
1917 Issue warnings needed for strict compliance to the standard
1918
1919 pedantic-errors
1920 Common
1921 Like -pedantic but issue them as errors
1922
1923 pg
1924 Driver
1925
1926 pipe
1927 Driver Var(use_pipes)
1928
1929 print-file-name=
1930 Driver JoinedOrMissing Var(print_file_name)
1931
1932 print-libgcc-file-name
1933 Driver
1934
1935 print-multi-directory
1936 Driver Var(print_multi_directory)
1937
1938 print-multi-lib
1939 Driver Var(print_multi_lib)
1940
1941 print-multi-os-directory
1942 Driver Var(print_multi_os_directory)
1943
1944 print-prog-name=
1945 Driver JoinedOrMissing Var(print_prog_name)
1946
1947 print-search-dirs
1948 Driver Var(print_search_dirs)
1949
1950 print-sysroot
1951 Driver Var(print_sysroot)
1952
1953 print-sysroot-headers-suffix
1954 Driver Var(print_sysroot_headers_suffix)
1955
1956 quiet
1957 Common Var(quiet_flag) RejectDriver
1958 Do not display functions compiled or elapsed time
1959
1960 save-temps
1961 Driver
1962
1963 save-temps=
1964 Driver Joined
1965
1966 time
1967 Driver Var(report_times)
1968
1969 time=
1970 Driver JoinedOrMissing
1971
1972 u
1973 Driver Joined Separate
1974
1975 undef
1976 Driver
1977 ; C option, but driver must not handle as "-u ndef".
1978
1979 v
1980 Driver
1981
1982 version
1983 Common Var(version_flag) RejectDriver
1984 Display the compiler's version
1985
1986 w
1987 Common Var(inhibit_warnings)
1988 Suppress warnings
1989
1990 wrapper
1991 Driver Separate Var(wrapper_string)
1992
1993 x
1994 Driver Joined Separate
1995
1996 shared
1997 Common RejectNegative Negative(pie)
1998 Create a shared library
1999
2000 shared-libgcc
2001 Driver
2002
2003 specs
2004 Driver Separate Alias(specs=)
2005
2006 specs=
2007 Driver Joined
2008
2009 static
2010 Driver
2011
2012 static-libgcc
2013 Driver
2014
2015 static-libgfortran
2016 Driver
2017 ; Documented for Fortran, but always accepted by driver.
2018
2019 static-libstdc++
2020 Driver
2021
2022 symbolic
2023 Driver
2024
2025 pie
2026 Common RejectNegative Negative(shared)
2027 Create a position independent executable
2028
2029 ; This comment is to ensure we retain the blank line above.