gcc/common.opt

   1 ; Options for the language- and target-independent parts of the compiler.
   2
   3 ; Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012
   4 ; Free Software Foundation, Inc.
   5 ;
   6 ; This file is part of GCC.
   7 ;
   8 ; GCC is free software; you can redistribute it and/or modify it under
   9 ; the terms of the GNU General Public License as published by the Free
  10 ; Software Foundation; either version 3, or (at your option) any later
  11 ; version.
  12 ;
  13 ; GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  14 ; WARRANTY; without even the implied warranty of MERCHANTABILITY or
  15 ; FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  16 ; for more details.
  17 ;
  18 ; You should have received a copy of the GNU General Public License
  19 ; along with GCC; see the file COPYING3.  If not see
  20 ; <http://www.gnu.org/licenses/>.
  21
  22 ; See the GCC internals manual (options.texi) for a description of this file's format.
  23
  24 ; Please try to keep this file in ASCII collating order.
  25
  26 Variable
  27 int target_flags
  28
  29 Variable
  30 int optimize
  31
  32 Variable
  33 int optimize_size
  34
  35 ; Not used directly to control optimizations, only to save -Ofast
  36 ; setting for "optimize" attributes.
  37 Variable
  38 int optimize_fast
  39
  40 ; True if this is the lto front end.  This is used to disable gimple
  41 ; generation and lowering passes that are normally run on the output
  42 ; of a front end.  These passes must be bypassed for lto since they
  43 ; have already been done before the gimple was written.
  44 Variable
  45 bool in_lto_p = false
  46
  47 ; 0 means straightforward implementation of complex divide acceptable.
  48 ; 1 means wide ranges of inputs must work for complex divide.
  49 ; 2 means C99-like requirements for complex multiply and divide.
  50 Variable
  51 int flag_complex_method = 1
  52
  53 ; Nonzero if subexpressions must be evaluated from left-to-right.
  54 Variable
  55 int flag_evaluation_order = 0
  56
  57 ; Language specific warning pass for unused results.
  58 Variable
  59 bool flag_warn_unused_result = false
  60
  61 Variable
  62 int *param_values
  63
  64 ; Nonzero if we should write GIMPLE bytecode for link-time optimization.
  65 Variable
  66 int flag_generate_lto
  67
  68 ; True to warn about any objects definitions whose size is larger
  69 ; than N bytes.  Also want about function definitions whose returned
  70 ; values are larger than N bytes, where N is 'larger_than_size'.
  71 Variable
  72 bool warn_larger_than
  73
  74 Variable
  75 HOST_WIDE_INT larger_than_size
  76
  77 ; True to warn about any function whose frame size is larger
  78 ; than N bytes.
  79 Variable
  80 bool warn_frame_larger_than
  81
  82 Variable
  83 HOST_WIDE_INT frame_larger_than_size
  84
  85 ; Nonzero means we should be saving declaration info into a .X file.
  86 Variable
  87 int flag_gen_aux_info = 0
  88
  89 ; Nonzero if we are compiling code for a shared library, zero for
  90 ; executable.
  91 Variable
  92 int flag_shlib
  93
  94 ; These two are really VEC(char_p,heap) *.
  95
  96 Variable
  97 void *flag_instrument_functions_exclude_functions
  98
  99 Variable
 100 void *flag_instrument_functions_exclude_files
 101
 102 ; Generic structs (e.g. templates not explicitly specialized)
 103 ; may not have a compilation unit associated with them, and so
 104 ; may need to be treated differently from ordinary structs.
 105 ;
 106 ; Structs only handled by reference (indirectly), will also usually
 107 ; not need as much debugging information.
 108
 109 Variable
 110 enum debug_struct_file debug_struct_ordinary[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
 111
 112 Variable
 113 enum debug_struct_file debug_struct_generic[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
 114
 115 ; True if we should exit after parsing options.
 116 Variable
 117 bool exit_after_options
 118
 119 ; Type(s) of debugging information we are producing (if any).  See
 120 ; flag-types.h for the definitions of the different possible types of
 121 ; debugging information.
 122 Variable
 123 enum debug_info_type write_symbols = NO_DEBUG
 124
 125 ; Level of debugging information we are producing.  See flag-types.h
 126 ; for the definitions of the different possible levels.
 127 Variable
 128 enum debug_info_levels debug_info_level = DINFO_LEVEL_NONE
 129
 130 ; Nonzero means use GNU-only extensions in the generated symbolic
 131 ; debugging information.  Currently, this only has an effect when
 132 ; write_symbols is set to DBX_DEBUG, XCOFF_DEBUG, or DWARF_DEBUG.
 133 Variable
 134 bool use_gnu_debug_info_extensions
 135
 136 ; Original value of maximum field alignment in bytes, specified via
 137 ; -fpack-struct=<value>.
 138 Variable
 139 unsigned int initial_max_fld_align = TARGET_DEFAULT_PACK_STRUCT
 140
 141 Variable
 142 enum vect_verbosity_levels user_vect_verbosity_level = MAX_VERBOSITY_LEVEL
 143
 144 ; Type of stack check.
 145 Variable
 146 enum stack_check_type flag_stack_check = NO_STACK_CHECK
 147
 148 ; True if stack usage information needs to be computed.
 149 Variable
 150 bool flag_stack_usage_info = false
 151
 152 ; -dA causes debug commentary information to be produced in
 153 ; the generated assembly code (to make it more readable).  This option
 154 ; is generally only of use to those who actually need to read the
 155 ; generated assembly code (perhaps while debugging the compiler itself).
 156 ; Currently, this switch is only used by dwarf2out.c; however, it is intended
 157 ; to be a catchall for printing debug information in the assembler file.
 158 Variable
 159 int flag_debug_asm
 160
 161 ; -dP causes the rtl to be emitted as a comment in assembly.
 162 Variable
 163 int flag_dump_rtl_in_asm
 164
 165 ; Whether -da was passed (used only in handle_common_deferred_options).
 166 Variable
 167 bool flag_dump_all_passed
 168
 169 ; Other flags saying which kinds of debugging dump have been requested.
 170
 171 Variable
 172 int rtl_dump_and_exit
 173
 174 Variable
 175 int flag_print_asm_name
 176
 177 Variable
 178 enum graph_dump_types graph_dump_format = no_graph
 179
 180 ; Name of top-level original source file (what was input to cpp).
 181 ; This comes from the #-command at the beginning of the actual input.
 182 ; If there isn't any there, then this is the cc1 input file name.
 183 Variable
 184 const char *main_input_filename
 185
 186 ; Pointer to base name in main_input_filename, with directories and a
 187 ; single final extension removed, and the length of this base
 188 ; name.
 189
 190 Variable
 191 const char *main_input_basename
 192
 193 Variable
 194 int main_input_baselength
 195
 196 ; Which options have been printed by --help.
 197 Variable
 198 char *help_printed
 199
 200 ; Which enums have been printed by --help.  0 = not printed, no
 201 ; relevant options seen, 1 = relevant option seen, not yet printed, 2
 202 ; = printed.
 203 Variable
 204 char *help_enum_printed
 205
 206 ; The number of columns for --help output.
 207 Variable
 208 unsigned int help_columns
 209
 210 ; Whether this options structure has been through finish_options
 211 Variable
 212 bool flag_opts_finished
 213
 214 ###
 215 Driver
 216
 217 -assemble
 218 Driver Alias(S)
 219
 220 -compile
 221 Driver Alias(c)
 222
 223 -coverage
 224 Driver Alias(coverage)
 225
 226 -debug
 227 Common Alias(g)
 228
 229 -dump
 230 Common Separate Alias(d)
 231
 232 -dump=
 233 Common Joined Alias(d)
 234
 235 -dumpbase
 236 Common Separate Alias(dumpbase)
 237
 238 -dumpdir
 239 Common Separate Alias(dumpdir)
 240
 241 -entry
 242 Driver Separate Alias(e)
 243
 244 -entry=
 245 Driver Joined Alias(e)
 246
 247 -extra-warnings
 248 Common Warning Alias(Wextra)
 249
 250 -for-assembler
 251 Driver Separate Alias(Xassembler)
 252
 253 -for-assembler=
 254 Driver JoinedOrMissing Alias(Xassembler)
 255
 256 -for-linker
 257 Driver Separate Alias(Xlinker)
 258
 259 -for-linker=
 260 Driver JoinedOrMissing Alias(Xlinker)
 261
 262 -force-link
 263 Driver Separate Alias(u)
 264
 265 -force-link=
 266 Driver Joined Alias(u)
 267
 268 -help
 269 Common Driver Var(help_flag)
 270 Display this information
 271
 272 -help=
 273 Common Driver Report Joined
 274 --help=<class>  Display descriptions of a specific class of options.  <class> is one or more of optimizers, target, warnings, undocumented, params
 275
 276 -language
 277 Driver Separate Alias(x)
 278
 279 -language=
 280 Driver Joined Alias(x)
 281
 282 -library-directory
 283 Driver Separate Alias(L)
 284
 285 -library-directory=
 286 Driver Joined Alias(L)
 287
 288 -no-canonical-prefixes
 289 Driver Alias(no-canonical-prefixes)
 290
 291 -no-standard-libraries
 292 Driver Alias(nostdlib)
 293
 294 -no-sysroot-suffix
 295 Driver Var(no_sysroot_suffix)
 296
 297 -no-warnings
 298 Common Alias(w)
 299
 300 -optimize
 301 Common Alias(O)
 302
 303 -output
 304 Common Driver Separate Alias(o) MissingArgError(missing filename after %qs)
 305
 306 -output=
 307 Common Driver Joined Alias(o) MissingArgError(missing filename after %qs)
 308
 309 -pass-exit-codes
 310 Driver Alias(pass-exit-codes)
 311
 312 -pedantic
 313 Common Alias(Wpedantic)
 314
 315 -pedantic-errors
 316 Common Alias(pedantic-errors)
 317
 318 -pie
 319 Driver Alias(pie)
 320
 321 -pipe
 322 Driver Alias(pipe)
 323
 324 -prefix
 325 Driver Separate Alias(B)
 326
 327 -prefix=
 328 Driver JoinedOrMissing Alias(B)
 329
 330 -preprocess
 331 Driver Alias(E)
 332
 333 -print-file-name
 334 Driver Separate Alias(print-file-name=)
 335
 336 -print-file-name=
 337 Driver JoinedOrMissing Alias(print-file-name=)
 338
 339 -print-libgcc-file-name
 340 Driver Alias(print-libgcc-file-name)
 341
 342 -print-multi-directory
 343 Driver Alias(print-multi-directory)
 344
 345 -print-multi-lib
 346 Driver Alias(print-multi-lib)
 347
 348 -print-multi-os-directory
 349 Driver Alias(print-multi-os-directory)
 350
 351 -print-prog-name
 352 Driver Separate Alias(print-prog-name=)
 353
 354 -print-prog-name=
 355 Driver JoinedOrMissing Alias(print-prog-name=)
 356
 357 -print-search-dirs
 358 Driver Alias(print-search-dirs)
 359
 360 -print-sysroot
 361 Driver Alias(print-sysroot)
 362
 363 -print-sysroot-headers-suffix
 364 Driver Alias(print-sysroot-headers-suffix)
 365
 366 -profile
 367 Common Alias(p)
 368
 369 -save-temps
 370 Driver Alias(save-temps)
 371
 372 -shared
 373 Driver Alias(shared)
 374
 375 -specs
 376 Driver Separate Alias(specs=)
 377
 378 -specs=
 379 Driver Joined Alias(specs=)
 380
 381 -static
 382 Driver Alias(static)
 383
 384 -symbolic
 385 Driver Alias(symbolic)
 386
 387 -target-help
 388 Common Driver
 389 Alias for --help=target
 390
 391 -time
 392 Driver Alias(time)
 393
 394 -verbose
 395 Driver Alias(v)
 396
 397 ;; The driver used to convert options such as --help into forms such
 398 ;; as -fhelp; the following four entries are for compatibility with
 399 ;; any direct uses of those (undocumented) -f forms
 400 fhelp
 401 Common Driver Alias(-help)
 402
 403 fhelp=
 404 Common Driver Joined Alias(-help=)
 405
 406 ftarget-help
 407 Common Driver Alias(-target-help)
 408
 409 fversion
 410 Common Driver Alias(-version)
 411
 412 -param
 413 Common Separate
 414 --param <param>=<value> Set parameter <param> to value.  See below for a complete list of parameters
 415
 416 -param=
 417 Common Joined Alias(-param)
 418
 419 -sysroot
 420 Driver Separate Alias(-sysroot=)
 421
 422 -sysroot=
 423 Driver JoinedOrMissing
 424
 425 -version
 426 Common Driver
 427
 428 B
 429 Driver Joined Separate
 430
 431 E
 432 Driver
 433
 434 L
 435 Driver Joined Separate
 436
 437 N
 438 Driver
 439
 440 O
 441 Common JoinedOrMissing Optimization
 442 -O<number>      Set optimization level to <number>
 443
 444 Os
 445 Common Optimization
 446 Optimize for space rather than speed
 447
 448 Ofast
 449 Common Optimization
 450 Optimize for speed disregarding exact standards compliance
 451
 452 Q
 453 Driver
 454
 455 Qn
 456 Driver Negative(Qy)
 457
 458 Qy
 459 Driver Negative(Qn)
 460
 461 R
 462 Driver Joined Separate
 463
 464 S
 465 Driver
 466
 467 T
 468 Driver Joined Separate
 469
 470 Tbss
 471 Driver Separate
 472
 473 Tbss=
 474 Driver Joined
 475
 476 Tdata
 477 Driver Separate
 478
 479 Tdata=
 480 Driver Joined
 481
 482 Ttext
 483 Driver Separate
 484
 485 Ttext=
 486 Driver Joined
 487
 488 W
 489 Common RejectNegative Warning Alias(Wextra)
 490 This switch is deprecated; use -Wextra instead
 491
 492 Wa,
 493 Driver JoinedOrMissing
 494
 495 Wl,
 496 Driver JoinedOrMissing
 497
 498 Wp,
 499 Driver JoinedOrMissing
 500
 501 Waggregate-return
 502 Common Var(warn_aggregate_return) Warning
 503 Warn about returning structures, unions or arrays
 504
 505 Warray-bounds
 506 Common Var(warn_array_bounds) Warning
 507 Warn if an array is accessed out of bounds
 508
 509 Wattributes
 510 Common Var(warn_attributes) Init(1) Warning
 511 Warn about inappropriate attribute usage
 512
 513 Wcast-align
 514 Common Var(warn_cast_align) Warning
 515 Warn about pointer casts which increase alignment
 516
 517 Wcpp
 518 Common Var(warn_cpp) Init(1) Warning
 519 Warn when a #warning directive is encountered
 520
 521 Wdeprecated-declarations
 522 Common Var(warn_deprecated_decl) Init(1) Warning
 523 Warn about uses of __attribute__((deprecated)) declarations
 524
 525 Wdisabled-optimization
 526 Common Var(warn_disabled_optimization) Warning
 527 Warn when an optimization pass is disabled
 528
 529 Werror
 530 Common Var(warnings_are_errors)
 531 Treat all warnings as errors
 532
 533 Werror=
 534 Common Joined
 535 Treat specified warning as error
 536
 537 Wextra
 538 Common Var(extra_warnings) Warning
 539 Print extra (possibly unwanted) warnings
 540
 541 Wfatal-errors
 542 Common Var(flag_fatal_errors)
 543 Exit on the first error occurred
 544
 545 Wframe-larger-than=
 546 Common RejectNegative Joined UInteger
 547 -Wframe-larger-than=<number>    Warn if a function's stack frame requires more than <number> bytes
 548
 549 Wfree-nonheap-object
 550 Common Var(warn_free_nonheap_object) Init(1) Warning
 551 Warn when attempting to free a non-heap object
 552
 553 Winline
 554 Common Var(warn_inline) Warning
 555 Warn when an inlined function cannot be inlined
 556
 557 Winvalid-memory-model
 558 Common Var(warn_invalid_memory_model) Init(1) Warning
 559 Warn when an atomic memory model parameter is known to be outside the valid range.
 560
 561 Wlarger-than-
 562 Common RejectNegative Joined Warning Undocumented Alias(Wlarger-than=)
 563
 564 Wlarger-than=
 565 Common RejectNegative Joined UInteger Warning
 566 -Wlarger-than=<number>  Warn if an object is larger than <number> bytes
 567
 568 Wunsafe-loop-optimizations
 569 Common Var(warn_unsafe_loop_optimizations) Warning
 570 Warn if the loop cannot be optimized due to nontrivial assumptions.
 571
 572 Wmissing-noreturn
 573 Common Alias(Wsuggest-attribute=noreturn)
 574
 575 Woverflow
 576 Common Var(warn_overflow) Init(1) Warning
 577 Warn about overflow in arithmetic expressions
 578
 579 Wpacked
 580 Common Var(warn_packed) Warning
 581 Warn when the packed attribute has no effect on struct layout
 582
 583 Wpadded
 584 Common Var(warn_padded) Warning
 585 Warn when padding is required to align structure members
 586
 587 Wpedantic
 588 Common Var(pedantic) Warning
 589 Issue warnings needed for strict compliance to the standard
 590
 591 Wshadow
 592 Common Var(warn_shadow) Warning
 593 Warn when one local variable shadows another
 594
 595 Wstack-protector
 596 Common Var(warn_stack_protect) Warning
 597 Warn when not issuing stack smashing protection for some reason
 598
 599 Wstack-usage=
 600 Common Joined RejectNegative UInteger Var(warn_stack_usage) Init(-1) Warning
 601 Warn if stack usage might be larger than specified amount
 602
 603 Wstrict-aliasing
 604 Common Warning
 605 Warn about code which might break strict aliasing rules
 606
 607 Wstrict-aliasing=
 608 Common Joined RejectNegative UInteger Var(warn_strict_aliasing) Init(-1) Warning
 609 Warn about code which might break strict aliasing rules
 610
 611 Wstrict-overflow
 612 Common Warning
 613 Warn about optimizations that assume that signed overflow is undefined
 614
 615 Wstrict-overflow=
 616 Common Joined RejectNegative UInteger Var(warn_strict_overflow) Init(-1) Warning
 617 Warn about optimizations that assume that signed overflow is undefined
 618
 619 Wsuggest-attribute=const
 620 Common Var(warn_suggest_attribute_const) Warning
 621 Warn about functions which might be candidates for __attribute__((const))
 622
 623 Wsuggest-attribute=pure
 624 Common Var(warn_suggest_attribute_pure) Warning
 625 Warn about functions which might be candidates for __attribute__((pure))
 626
 627 Wsuggest-attribute=noreturn
 628 Common Var(warn_suggest_attribute_noreturn) Warning
 629 Warn about functions which might be candidates for __attribute__((noreturn))
 630
 631 Wswitch
 632 Common Var(warn_switch) Warning
 633 Warn about enumerated switches, with no default, missing a case
 634
 635 Wswitch-default
 636 Common Var(warn_switch_default) Warning
 637 Warn about enumerated switches missing a \"default:\" statement
 638
 639 Wswitch-enum
 640 Common Var(warn_switch_enum) Warning
 641 Warn about all enumerated switches missing a specific case
 642
 643 Wsystem-headers
 644 Common Var(warn_system_headers) Warning
 645 Do not suppress warnings from system headers
 646
 647 Wtrampolines
 648 Common Var(warn_trampolines) Warning
 649 Warn whenever a trampoline is generated
 650
 651 Wtype-limits
 652 Common Var(warn_type_limits) Warning EnabledBy(Wextra)
 653 Warn if a comparison is always true or always false due to the limited range of the data type
 654
 655 Wuninitialized
 656 Common Var(warn_uninitialized) Warning EnabledBy(Wextra)
 657 Warn about uninitialized automatic variables
 658
 659 Wmaybe-uninitialized
 660 Common Var(warn_maybe_uninitialized) Warning EnabledBy(Wuninitialized)
 661 Warn about maybe uninitialized automatic variables
 662
 663 Wunreachable-code
 664 Common Ignore
 665 Does nothing. Preserved for backward compatibility.
 666
 667 Wunused
 668 Common Var(warn_unused) Init(0) Warning
 669 Enable all -Wunused- warnings
 670
 671 Wunused-but-set-parameter
 672 Common Var(warn_unused_but_set_parameter) Init(-1) Warning
 673 Warn when a function parameter is only set, otherwise unused
 674
 675 Wunused-but-set-variable
 676 Common Var(warn_unused_but_set_variable) Warning EnabledBy(Wunused)
 677 Warn when a variable is only set, otherwise unused
 678
 679 Wunused-function
 680 Common Var(warn_unused_function) Warning EnabledBy(Wunused)
 681 Warn when a function is unused
 682
 683 Wunused-label
 684 Common Var(warn_unused_label) Warning EnabledBy(Wunused)
 685 Warn when a label is unused
 686
 687 Wunused-parameter
 688 Common Var(warn_unused_parameter) Init(-1) Warning
 689 Warn when a function parameter is unused
 690
 691 Wunused-value
 692 Common Var(warn_unused_value) Warning EnabledBy(Wunused)
 693 Warn when an expression value is unused
 694
 695 Wunused-variable
 696 Common Var(warn_unused_variable) Warning EnabledBy(Wunused)
 697 Warn when a variable is unused
 698
 699 Wcoverage-mismatch
 700 Common Var(warn_coverage_mismatch) Init(1) Warning
 701 Warn in case profiles in -fprofile-use do not match
 702
 703 Wvector-operation-performance
 704 Common Var(warn_vector_operation_performance) Warning
 705 Warn when a vector operation is compiled outside the SIMD
 706
 707 Xassembler
 708 Driver Separate
 709
 710 Xlinker
 711 Driver Separate
 712
 713 Xpreprocessor
 714 Driver Separate
 715
 716 Z
 717 Driver
 718
 719 aux-info
 720 Common Separate Var(aux_info_file_name)
 721 -aux-info <file>        Emit declaration information into <file>
 722
 723 aux-info=
 724 Common Joined Alias(aux-info)
 725
 726 auxbase
 727 Common Separate RejectDriver Var(aux_base_name)
 728
 729 auxbase-strip
 730 Common Separate RejectDriver
 731
 732 coverage
 733 Driver
 734
 735 c
 736 Driver
 737
 738 d
 739 Common Joined
 740 -d<letters>     Enable dumps from specific passes of the compiler
 741
 742 dumpbase
 743 Common Separate Var(dump_base_name)
 744 -dumpbase <file>        Set the file basename to be used for dumps
 745
 746 dumpdir
 747 Common Separate Var(dump_dir_name)
 748 -dumpdir <dir>  Set the directory name to be used for dumps
 749
 750 dumpmachine
 751 Driver
 752
 753 dumpspecs
 754 Driver
 755
 756 dumpversion
 757 Driver
 758
 759 e
 760 Driver Joined Separate
 761
 762 ; This option has historically been passed down to the linker by an
 763 ; accident of a %{e*} spec, so ensure it continues to be passed down
 764 ; as a single option.  The supported option for this purpose is
 765 ; -rdynamic.  See PR 47390.
 766 export-dynamic
 767 Driver Undocumented
 768
 769 ; The version of the C++ ABI in use.  The following values are allowed:
 770 ;
 771 ; 0: The version of the ABI believed most conformant with the C++ ABI
 772 ;    specification.  This ABI may change as bugs are discovered and fixed.
 773 ;    Therefore, 0 will not necessarily indicate the same ABI in different
 774 ;    versions of G++.
 775 ;
 776 ; 1: The version of the ABI first used in G++ 3.2.
 777 ;
 778 ; 2: The version of the ABI first used in G++ 3.4 (and current default).
 779 ;
 780 ; 3: The version of the ABI that fixes the missing underscore
 781 ;    in template non-type arguments of pointer type.
 782 ;
 783 ; 4: The version of the ABI that introduces unambiguous mangling of
 784 ;    vector types.  First selectable in G++ 4.5.
 785 ;
 786 ; 5: The version of the ABI that ignores attribute const/noreturn
 787 ;    in function pointer mangling, and corrects mangling of decltype and
 788 ;    function parameters used in other parameters and the return type.
 789 ;    First selectable in G++ 4.6.
 790 ;
 791 ; 6: The version of the ABI that doesn't promote scoped enums to int and
 792 ;    changes the mangling of template argument packs, const/static_cast,
 793 ;    prefix ++ and --, and a class scope function used as a template
 794 ;    argument.
 795 ;    First selectable in G++ 4.7.
 796 ;
 797 ; 7: The version of the ABI that treats nullptr_t as a builtin type.
 798 ;    First selectable in G++ 4.8.
 799 ; Additional positive integers will be assigned as new versions of
 800 ; the ABI become the default version of the ABI.
 801 fabi-version=
 802 Common Joined RejectNegative UInteger Var(flag_abi_version) Init(2)
 803
 804 falign-functions
 805 Common Report Var(align_functions,0) Optimization UInteger
 806 Align the start of functions
 807
 808 falign-functions=
 809 Common RejectNegative Joined UInteger Var(align_functions)
 810
 811 falign-jumps
 812 Common Report Var(align_jumps,0) Optimization UInteger
 813 Align labels which are only reached by jumping
 814
 815 falign-jumps=
 816 Common RejectNegative Joined UInteger Var(align_jumps)
 817
 818 falign-labels
 819 Common Report Var(align_labels,0) Optimization UInteger
 820 Align all labels
 821
 822 falign-labels=
 823 Common RejectNegative Joined UInteger Var(align_labels)
 824
 825 falign-loops
 826 Common Report Var(align_loops,0) Optimization UInteger
 827 Align the start of loops
 828
 829 falign-loops=
 830 Common RejectNegative Joined UInteger Var(align_loops)
 831
 832 fargument-alias
 833 Common Ignore
 834 Does nothing. Preserved for backward compatibility.
 835
 836 fargument-noalias
 837 Common Ignore
 838 Does nothing. Preserved for backward compatibility.
 839
 840 fargument-noalias-global
 841 Common Ignore
 842 Does nothing. Preserved for backward compatibility.
 843
 844 fargument-noalias-anything
 845 Common Ignore
 846 Does nothing. Preserved for backward compatibility.
 847
 848 fasynchronous-unwind-tables
 849 Common Report Var(flag_asynchronous_unwind_tables) Optimization
 850 Generate unwind tables that are exact at each instruction boundary
 851
 852 fauto-inc-dec
 853 Common Report Var(flag_auto_inc_dec) Init(1)
 854 Generate auto-inc/dec instructions
 855
 856 ; -fcheck-bounds causes gcc to generate array bounds checks.
 857 ; For C, C++ and ObjC: defaults off.
 858 ; For Java: defaults to on.
 859 ; For Fortran: defaults to off.
 860 fbounds-check
 861 Common Report Var(flag_bounds_check)
 862 Generate code to check bounds before indexing arrays
 863
 864 fbranch-count-reg
 865 Common Report Var(flag_branch_on_count_reg) Init(1) Optimization
 866 Replace add, compare, branch with branch on count register
 867
 868 fbranch-probabilities
 869 Common Report Var(flag_branch_probabilities) Optimization
 870 Use profiling information for branch probabilities
 871
 872 fbranch-target-load-optimize
 873 Common Report Var(flag_branch_target_load_optimize) Optimization
 874 Perform branch target load optimization before prologue / epilogue threading
 875
 876 fbranch-target-load-optimize2
 877 Common Report Var(flag_branch_target_load_optimize2) Optimization
 878 Perform branch target load optimization after prologue / epilogue threading
 879
 880 fbtr-bb-exclusive
 881 Common Report Var(flag_btr_bb_exclusive) Optimization
 882 Restrict target load migration not to re-use registers in any basic block
 883
 884 fcall-saved-
 885 Common Joined RejectNegative Var(common_deferred_options) Defer
 886 -fcall-saved-<register> Mark <register> as being preserved across functions
 887
 888 fcall-used-
 889 Common Joined RejectNegative Var(common_deferred_options) Defer
 890 -fcall-used-<register>  Mark <register> as being corrupted by function calls
 891
 892 ; Nonzero for -fcaller-saves: allocate values in regs that need to
 893 ; be saved across function calls, if that produces overall better code.
 894 ; Optional now, so people can test it.
 895 fcaller-saves
 896 Common Report Var(flag_caller_saves) Optimization
 897 Save registers around function calls
 898
 899 fcheck-data-deps
 900 Common Report Var(flag_check_data_deps)
 901 Compare the results of several data dependence analyzers.
 902
 903 fcombine-stack-adjustments
 904 Common Report Var(flag_combine_stack_adjustments) Optimization
 905 Looks for opportunities to reduce stack adjustments and stack references.
 906
 907 fcommon
 908 Common Report Var(flag_no_common,0) Optimization
 909 Do not put uninitialized globals in the common section
 910
 911 fcompare-debug
 912 Driver
 913 ; Converted by the driver to -fcompare-debug= options.
 914
 915 fcompare-debug=
 916 Common Driver JoinedOrMissing RejectNegative Var(flag_compare_debug_opt)
 917 -fcompare-debug[=<opts>]        Compile with and without e.g. -gtoggle, and compare the final-insns dump
 918
 919 fcompare-debug-second
 920 Common Driver RejectNegative Var(flag_compare_debug)
 921 Run only the second compilation of -fcompare-debug
 922
 923 fcompare-elim
 924 Common Report Var(flag_compare_elim_after_reload) Optimization
 925 Perform comparison elimination after register allocation has finished
 926
 927 fconserve-stack
 928 Common Var(flag_conserve_stack) Optimization
 929 Do not perform optimizations increasing noticeably stack usage
 930
 931 fcprop-registers
 932 Common Report Var(flag_cprop_registers) Optimization
 933 Perform a register copy-propagation optimization pass
 934
 935 fcrossjumping
 936 Common Report Var(flag_crossjumping) Optimization
 937 Perform cross-jumping optimization
 938
 939 fcse-follow-jumps
 940 Common Report Var(flag_cse_follow_jumps) Optimization
 941 When running CSE, follow jumps to their targets
 942
 943 fcse-skip-blocks
 944 Common Ignore
 945 Does nothing.  Preserved for backward compatibility.
 946
 947 fcx-limited-range
 948 Common Report Var(flag_cx_limited_range) Optimization SetByCombined
 949 Omit range reduction step when performing complex division
 950
 951 fcx-fortran-rules
 952 Common Report Var(flag_cx_fortran_rules) Optimization
 953 Complex multiplication and division follow Fortran rules
 954
 955 fdata-sections
 956 Common Report Var(flag_data_sections) Optimization
 957 Place data items into their own section
 958
 959 fdbg-cnt-list
 960 Common Report Var(common_deferred_options) Defer
 961 List all available debugging counters with their limits and counts.
 962
 963 fdbg-cnt=
 964 Common RejectNegative Joined Var(common_deferred_options) Defer
 965 -fdbg-cnt=<counter>:<limit>[,<counter>:<limit>,...]     Set the debug counter limit.
 966
 967 fdebug-prefix-map=
 968 Common Joined RejectNegative Var(common_deferred_options) Defer
 969 Map one directory name to another in debug information
 970
 971 fdebug-types-section
 972 Common Report Var(flag_debug_types_section) Init(0)
 973 Output .debug_types section when using DWARF v4 debuginfo.
 974
 975 ; Nonzero for -fdefer-pop: don't pop args after each function call
 976 ; instead save them up to pop many calls' args with one insns.
 977 fdefer-pop
 978 Common Report Var(flag_defer_pop) Optimization
 979 Defer popping functions args from stack until later
 980
 981 fdelayed-branch
 982 Common Report Var(flag_delayed_branch) Optimization
 983 Attempt to fill delay slots of branch instructions
 984
 985 fdelete-dead-exceptions
 986 Common Report Var(flag_delete_dead_exceptions) Init(0)
 987 Delete dead instructions that may throw exceptions
 988
 989 fdelete-null-pointer-checks
 990 Common Report Var(flag_delete_null_pointer_checks) Init(1) Optimization
 991 Delete useless null pointer checks
 992
 993 fdevirtualize
 994 Common Report Var(flag_devirtualize) Optimization
 995 Try to convert virtual calls to direct ones.
 996
 997 fdiagnostics-show-location=
 998 Common Joined RejectNegative Enum(diagnostic_prefixing_rule)
 999 -fdiagnostics-show-location=[once|every-line]   How often to emit source location at the beginning of line-wrapped diagnostics
1000
1001 ; Required for these enum values.
1002 SourceInclude
1003 pretty-print.h
1004
1005 Enum
1006 Name(diagnostic_prefixing_rule) Type(int)
1007
1008 EnumValue
1009 Enum(diagnostic_prefixing_rule) String(once) Value(DIAGNOSTICS_SHOW_PREFIX_ONCE)
1010
1011 EnumValue
1012 Enum(diagnostic_prefixing_rule) String(every-line) Value(DIAGNOSTICS_SHOW_PREFIX_EVERY_LINE)
1013
1014 fdiagnostics-show-caret
1015 Common Var(flag_diagnostics_show_caret) Init(1)
1016 Show the source line with a caret indicating the column
1017
1018 fdiagnostics-show-option
1019 Common Var(flag_diagnostics_show_option) Init(1)
1020 Amend appropriate diagnostic messages with the command line option that controls them
1021
1022 fdisable-
1023 Common Joined RejectNegative Var(common_deferred_options) Defer
1024 -fdisable-[tree|rtl|ipa]-<pass>=range1+range2 disables an optimization pass
1025
1026 fenable-
1027 Common Joined RejectNegative Var(common_deferred_options) Defer
1028 -fenable-[tree|rtl|ipa]-<pass>=range1+range2 enables an optimization pass
1029
1030 fdump-
1031 Common Joined RejectNegative Var(common_deferred_options) Defer
1032 -fdump-<type>   Dump various compiler internals to a file
1033
1034 fdump-final-insns
1035 Driver RejectNegative
1036
1037 fdump-final-insns=
1038 Common RejectNegative Joined Var(flag_dump_final_insns)
1039 -fdump-final-insns=filename     Dump to filename the insns at the end of translation
1040
1041 fdump-go-spec=
1042 Common RejectNegative Joined Var(flag_dump_go_spec)
1043 -fdump-go-spec=filename Write all declarations to file as Go code
1044
1045 fdump-noaddr
1046 Common Report Var(flag_dump_noaddr)
1047 Suppress output of addresses in debugging dumps
1048
1049 fdump-passes
1050 Common Var(flag_dump_passes) Init(0)
1051 Dump optimization passes
1052
1053 fdump-unnumbered
1054 Common Report Var(flag_dump_unnumbered)
1055 Suppress output of instruction numbers, line number notes and addresses in debugging dumps
1056
1057 fdump-unnumbered-links
1058 Common Report Var(flag_dump_unnumbered_links)
1059 Suppress output of previous and next insn numbers in debugging dumps
1060
1061 fdwarf2-cfi-asm
1062 Common Report Var(flag_dwarf2_cfi_asm) Init(HAVE_GAS_CFI_DIRECTIVE)
1063 Enable CFI tables via GAS assembler directives.
1064
1065 fearly-inlining
1066 Common Report Var(flag_early_inlining) Init(1) Optimization
1067 Perform early inlining
1068
1069 feliminate-dwarf2-dups
1070 Common Report Var(flag_eliminate_dwarf2_dups)
1071 Perform DWARF2 duplicate elimination
1072
1073 fipa-sra
1074 Common Report Var(flag_ipa_sra) Init(0) Optimization
1075 Perform interprocedural reduction of aggregates
1076
1077 feliminate-unused-debug-symbols
1078 Common Report Var(flag_debug_only_used_symbols)
1079 Perform unused type elimination in debug info
1080
1081 feliminate-unused-debug-types
1082 Common Report Var(flag_eliminate_unused_debug_types) Init(1)
1083 Perform unused type elimination in debug info
1084
1085 femit-class-debug-always
1086 Common Report Var(flag_emit_class_debug_always) Init(0)
1087 Do not suppress C++ class debug information.
1088
1089 fexceptions
1090 Common Report Var(flag_exceptions) Optimization
1091 Enable exception handling
1092
1093 fexpensive-optimizations
1094 Common Report Var(flag_expensive_optimizations) Optimization
1095 Perform a number of minor, expensive optimizations
1096
1097 fexcess-precision=
1098 Common Joined RejectNegative Enum(excess_precision) Var(flag_excess_precision_cmdline) Init(EXCESS_PRECISION_DEFAULT)
1099 -fexcess-precision=[fast|standard]      Specify handling of excess floating-point precision
1100
1101 Enum
1102 Name(excess_precision) Type(enum excess_precision) UnknownError(unknown excess precision style %qs)
1103
1104 EnumValue
1105 Enum(excess_precision) String(fast) Value(EXCESS_PRECISION_FAST)
1106
1107 EnumValue
1108 Enum(excess_precision) String(standard) Value(EXCESS_PRECISION_STANDARD)
1109
1110 ffast-math
1111 Common
1112
1113 ffat-lto-objects
1114 Common Var(flag_fat_lto_objects) Init(1)
1115 Output lto objects containing both the intermediate language and binary output.
1116
1117 ffinite-math-only
1118 Common Report Var(flag_finite_math_only) Optimization SetByCombined
1119 Assume no NaNs or infinities are generated
1120
1121 ffixed-
1122 Common Joined RejectNegative Var(common_deferred_options) Defer
1123 -ffixed-<register>      Mark <register> as being unavailable to the compiler
1124
1125 ffloat-store
1126 Common Report Var(flag_float_store) Optimization
1127 Don't allocate floats and doubles in extended-precision registers
1128
1129 fforce-addr
1130 Common Ignore
1131 Does nothing.  Preserved for backward compatibility.
1132
1133 fforward-propagate
1134 Common Report Var(flag_forward_propagate) Optimization
1135 Perform a forward propagation pass on RTL
1136
1137 ffp-contract=
1138 Common Joined RejectNegative Enum(fp_contract_mode) Var(flag_fp_contract_mode) Init(FP_CONTRACT_FAST)
1139 -ffp-contract=[off|on|fast] Perform floating-point expression contraction.
1140
1141 Enum
1142 Name(fp_contract_mode) Type(enum fp_contract_mode) UnknownError(unknown floating point contraction style %qs)
1143
1144 EnumValue
1145 Enum(fp_contract_mode) String(off) Value(FP_CONTRACT_OFF)
1146
1147 ; Not implemented, fall back to conservative FP_CONTRACT_OFF.
1148 EnumValue
1149 Enum(fp_contract_mode) String(on) Value(FP_CONTRACT_OFF)
1150
1151 EnumValue
1152 Enum(fp_contract_mode) String(fast) Value(FP_CONTRACT_FAST)
1153
1154 ; Nonzero means don't put addresses of constant functions in registers.
1155 ; Used for compiling the Unix kernel, where strange substitutions are
1156 ; done on the assembly output.
1157 ffunction-cse
1158 Common Report Var(flag_no_function_cse,0)
1159 Allow function addresses to be held in registers
1160
1161 ffunction-sections
1162 Common Report Var(flag_function_sections)
1163 Place each function into its own section
1164
1165 fgcse
1166 Common Report Var(flag_gcse) Optimization
1167 Perform global common subexpression elimination
1168
1169 fgcse-lm
1170 Common Report Var(flag_gcse_lm) Init(1) Optimization
1171 Perform enhanced load motion during global common subexpression elimination
1172
1173 fgcse-sm
1174 Common Report Var(flag_gcse_sm) Init(0) Optimization
1175 Perform store motion after global common subexpression elimination
1176
1177 fgcse-las
1178 Common Report Var(flag_gcse_las) Init(0) Optimization
1179 Perform redundant load after store elimination in global common subexpression
1180 elimination
1181
1182 fgcse-after-reload
1183 Common Report Var(flag_gcse_after_reload) Optimization
1184 Perform global common subexpression elimination after register allocation
1185 has finished
1186
1187 ; This option is not documented yet as its semantics will change.
1188 fgraphite
1189 Common Report Var(flag_graphite)
1190 Enable in and out of Graphite representation
1191
1192 fgraphite-identity
1193 Common Report Var(flag_graphite_identity) Optimization
1194 Enable Graphite Identity transformation
1195
1196 fhoist-adjacent-loads
1197 Common Report Var(flag_hoist_adjacent_loads) Optimization
1198 Enable hoisting adjacent loads to encourage generating conditional move
1199 instructions
1200
1201 floop-parallelize-all
1202 Common Report Var(flag_loop_parallelize_all) Optimization
1203 Mark all loops as parallel
1204
1205 floop-strip-mine
1206 Common Report Var(flag_loop_strip_mine) Optimization
1207 Enable Loop Strip Mining transformation
1208
1209 floop-interchange
1210 Common Report Var(flag_loop_interchange) Optimization
1211 Enable Loop Interchange transformation
1212
1213 floop-block
1214 Common Report Var(flag_loop_block) Optimization
1215 Enable Loop Blocking transformation
1216
1217 fgnu-tm
1218 Common Report Var(flag_tm)
1219 Enable support for GNU transactional memory
1220
1221 floop-flatten
1222 Common Ignore
1223 Does nothing. Preserved for backward compatibility.
1224
1225 floop-nest-optimize
1226 Common Report Var(flag_loop_optimize_isl) Optimization
1227 Enable the ISL based loop nest optimizer
1228
1229 fstrict-volatile-bitfields
1230 Common Report Var(flag_strict_volatile_bitfields) Init(-1)
1231 Force bitfield accesses to match their type width
1232
1233 fguess-branch-probability
1234 Common Report Var(flag_guess_branch_prob) Optimization
1235 Enable guessing of branch probabilities
1236
1237 ; Nonzero means ignore `#ident' directives.  0 means handle them.
1238 ; Generate position-independent code for executables if possible
1239 ; On SVR4 targets, it also controls whether or not to emit a
1240 ; string identifying the compiler.
1241 fident
1242 Common Report Var(flag_no_ident,0)
1243 Process #ident directives
1244
1245 fif-conversion
1246 Common Report Var(flag_if_conversion) Optimization
1247 Perform conversion of conditional jumps to branchless equivalents
1248
1249 fif-conversion2
1250 Common Report Var(flag_if_conversion2) Optimization
1251 Perform conversion of conditional jumps to conditional execution
1252
1253 fstack-reuse=
1254 Common Joined RejectNegative Enum(stack_reuse_level) Var(flag_stack_reuse) Init(SR_ALL)
1255 -fstack-reuse=[all|named_vars|none] Set stack reuse level for local variables.
1256
1257 Enum
1258 Name(stack_reuse_level) Type(enum stack_reuse_level) UnknownError(unknown Stack Reuse Level %qs)
1259
1260 EnumValue
1261 Enum(stack_reuse_level) String(all) Value(SR_ALL)
1262
1263 EnumValue
1264 Enum(stack_reuse_level) String(named_vars) Value(SR_NAMED_VARS)
1265
1266 EnumValue
1267 Enum(stack_reuse_level) String(none) Value(SR_NONE)
1268
1269 ftree-loop-if-convert
1270 Common Report Var(flag_tree_loop_if_convert) Init(-1) Optimization
1271 Convert conditional jumps in innermost loops to branchless equivalents
1272
1273 ftree-loop-if-convert-stores
1274 Common Report Var(flag_tree_loop_if_convert_stores) Optimization
1275 Also if-convert conditional jumps containing memory writes
1276
1277 ; -finhibit-size-directive inhibits output of .size for ELF.
1278 ; This is used only for compiling crtstuff.c,
1279 ; and it may be extended to other effects
1280 ; needed for crtstuff.c on other systems.
1281 finhibit-size-directive
1282 Common Report Var(flag_inhibit_size_directive)
1283 Do not generate .size directives
1284
1285 findirect-inlining
1286 Common Report Var(flag_indirect_inlining)
1287 Perform indirect inlining
1288
1289 ; General flag to enable inlining.  Specifying -fno-inline will disable
1290 ; all inlining apart from always-inline functions.
1291 finline
1292 Common Report Var(flag_no_inline,0) Init(0) Optimization
1293 Enable inlining of function declared \"inline\", disabling disables all inlining
1294
1295 finline-small-functions
1296 Common Report Var(flag_inline_small_functions) Optimization
1297 Integrate functions into their callers when code size is known not to grow
1298
1299 finline-functions
1300 Common Report Var(flag_inline_functions) Optimization
1301 Integrate functions not declared \"inline\" into their callers when profitable
1302
1303 finline-functions-called-once
1304 Common Report Var(flag_inline_functions_called_once) Optimization
1305 Integrate functions only required by their single caller
1306
1307 finline-limit-
1308 Common RejectNegative Joined Alias(finline-limit=)
1309
1310 finline-limit=
1311 Common RejectNegative Joined UInteger
1312 -finline-limit=<number> Limit the size of inlined functions to <number>
1313
1314 finline-atomics
1315 Common Report Var(flag_inline_atomics) Init(1) Optimization
1316 Inline __atomic operations when a lock free instruction sequence is available.
1317
1318 finstrument-functions
1319 Common Report Var(flag_instrument_function_entry_exit)
1320 Instrument function entry and exit with profiling calls
1321
1322 finstrument-functions-exclude-function-list=
1323 Common RejectNegative Joined
1324 -finstrument-functions-exclude-function-list=name,...  Do not instrument listed functions
1325
1326 finstrument-functions-exclude-file-list=
1327 Common RejectNegative Joined
1328 -finstrument-functions-exclude-file-list=filename,...  Do not instrument functions listed in files
1329
1330 fipa-cp
1331 Common Report Var(flag_ipa_cp) Optimization
1332 Perform Interprocedural constant propagation
1333
1334 fipa-cp-clone
1335 Common Report Var(flag_ipa_cp_clone) Optimization
1336 Perform cloning to make Interprocedural constant propagation stronger
1337
1338 fipa-profile
1339 Common Report Var(flag_ipa_profile) Init(0) Optimization
1340 Perform interprocedural profile propagation
1341
1342 fipa-pta
1343 Common Report Var(flag_ipa_pta) Init(0) Optimization
1344 Perform interprocedural points-to analysis
1345
1346 fipa-pure-const
1347 Common Report Var(flag_ipa_pure_const) Init(0) Optimization
1348 Discover pure and const functions
1349
1350 fipa-reference
1351 Common Report Var(flag_ipa_reference) Init(0) Optimization
1352 Discover readonly and non addressable static variables
1353
1354 fipa-matrix-reorg
1355 Common Ignore
1356 Does nothing. Preserved for backward compatibility.
1357
1358 fipa-struct-reorg
1359 Common Ignore
1360 Does nothing. Preserved for backward compatibility.
1361
1362 fira-algorithm=
1363 Common Joined RejectNegative Enum(ira_algorithm) Var(flag_ira_algorithm) Init(IRA_ALGORITHM_CB)
1364 -fira-algorithm=[CB|priority] Set the used IRA algorithm
1365
1366 Enum
1367 Name(ira_algorithm) Type(enum ira_algorithm) UnknownError(unknown IRA algorithm %qs)
1368
1369 EnumValue
1370 Enum(ira_algorithm) String(CB) Value(IRA_ALGORITHM_CB)
1371
1372 EnumValue
1373 Enum(ira_algorithm) String(priority) Value(IRA_ALGORITHM_PRIORITY)
1374
1375 fira-region=
1376 Common Joined RejectNegative Enum(ira_region) Var(flag_ira_region) Init(IRA_REGION_AUTODETECT)
1377 -fira-region=[one|all|mixed] Set regions for IRA
1378
1379 Enum
1380 Name(ira_region) Type(enum ira_region) UnknownError(unknown IRA region %qs)
1381
1382 EnumValue
1383 Enum(ira_region) String(one) Value(IRA_REGION_ONE)
1384
1385 EnumValue
1386 Enum(ira_region) String(all) Value(IRA_REGION_ALL)
1387
1388 EnumValue
1389 Enum(ira_region) String(mixed) Value(IRA_REGION_MIXED)
1390
1391 fira-loop-pressure
1392 Common Report Var(flag_ira_loop_pressure)
1393 Use IRA based register pressure calculation
1394 in RTL loop optimizations.
1395
1396 fira-share-save-slots
1397 Common Report Var(flag_ira_share_save_slots) Init(1)
1398 Share slots for saving different hard registers.
1399
1400 fira-share-spill-slots
1401 Common Report Var(flag_ira_share_spill_slots) Init(1)
1402 Share stack slots for spilled pseudo-registers.
1403
1404 fira-verbose=
1405 Common RejectNegative Joined UInteger Var(flag_ira_verbose) Init(5)
1406 -fira-verbose=<number>  Control IRA's level of diagnostic messages.
1407
1408 fivopts
1409 Common Report Var(flag_ivopts) Init(1) Optimization
1410 Optimize induction variables on trees
1411
1412 fjump-tables
1413 Common Var(flag_jump_tables) Init(1) Optimization
1414 Use jump tables for sufficiently large switch statements
1415
1416 fkeep-inline-functions
1417 Common Report Var(flag_keep_inline_functions)
1418 Generate code for functions even if they are fully inlined
1419
1420 fkeep-static-consts
1421 Common Report Var(flag_keep_static_consts) Init(1)
1422 Emit static const variables even if they are not used
1423
1424 fleading-underscore
1425 Common Report Var(flag_leading_underscore) Init(-1)
1426 Give external symbols a leading underscore
1427
1428 floop-optimize
1429 Common Ignore
1430 Does nothing.  Preserved for backward compatibility.
1431
1432 flto
1433 Common
1434 Enable link-time optimization.
1435
1436 flto=
1437 Common RejectNegative Joined Var(flag_lto)
1438 Link-time optimization with number of parallel jobs or jobserver.
1439
1440 flto-partition=1to1
1441 Common Var(flag_lto_partition_1to1)
1442 Partition symbols and vars at linktime based on object files they originate from
1443
1444 flto-partition=balanced
1445 Common Var(flag_lto_partition_balanced)
1446 Partition functions and vars at linktime into approximately same sized buckets
1447
1448 flto-partition=max
1449 Common Var(flag_lto_partition_max)
1450 Put every symbol into separate partition
1451
1452 flto-partition=none
1453 Common Var(flag_lto_partition_none)
1454 Disable partioning and streaming
1455
1456 ; The initial value of -1 comes from Z_DEFAULT_COMPRESSION in zlib.h.
1457 flto-compression-level=
1458 Common Joined RejectNegative UInteger Var(flag_lto_compression_level) Init(-1)
1459 -flto-compression-level=<number>        Use zlib compression level <number> for IL
1460
1461 flto-report
1462 Common Report Var(flag_lto_report) Init(0)
1463 Report various link-time optimization statistics
1464
1465 fmath-errno
1466 Common Report Var(flag_errno_math) Init(1) Optimization SetByCombined
1467 Set errno after built-in math functions
1468
1469 fmax-errors=
1470 Common Joined RejectNegative UInteger Var(flag_max_errors)
1471 -fmax-errors=<number>   Maximum number of errors to report
1472
1473 fmem-report
1474 Common Report Var(mem_report)
1475 Report on permanent memory allocation
1476
1477 fmem-report-wpa
1478 Common Report Var(mem_report_wpa)
1479 Report on permanent memory allocation in WPA only
1480
1481 ; This will attempt to merge constant section constants, if 1 only
1482 ; string constants and constants from constant pool, if 2 also constant
1483 ; variables.
1484 fmerge-all-constants
1485 Common Report Var(flag_merge_constants,2) Init(1) Optimization
1486 Attempt to merge identical constants and constant variables
1487
1488 fmerge-constants
1489 Common Report Var(flag_merge_constants,1) Optimization
1490 Attempt to merge identical constants across compilation units
1491
1492 fmerge-debug-strings
1493 Common Report Var(flag_merge_debug_strings) Init(1)
1494 Attempt to merge identical debug strings across compilation units
1495
1496 fmessage-length=
1497 Common RejectNegative Joined UInteger
1498 -fmessage-length=<number>       Limit diagnostics to <number> characters per line.  0 suppresses line-wrapping
1499
1500 fmodulo-sched
1501 Common Report Var(flag_modulo_sched) Optimization
1502 Perform SMS based modulo scheduling before the first scheduling pass
1503
1504 fmodulo-sched-allow-regmoves
1505 Common Report Var(flag_modulo_sched_allow_regmoves)
1506 Perform SMS based modulo scheduling with register moves allowed
1507
1508 fmove-loop-invariants
1509 Common Report Var(flag_move_loop_invariants) Init(1) Optimization
1510 Move loop invariant computations out of loops
1511
1512 fdce
1513 Common Var(flag_dce) Init(1) Optimization
1514 Use the RTL dead code elimination pass
1515
1516 fdse
1517 Common Var(flag_dse) Init(1) Optimization
1518 Use the RTL dead store elimination pass
1519
1520 freschedule-modulo-scheduled-loops
1521 Common Report Var(flag_resched_modulo_sched) Optimization
1522 Enable/Disable the traditional scheduling in loops that already passed modulo scheduling
1523
1524 fnon-call-exceptions
1525 Common Report Var(flag_non_call_exceptions) Optimization
1526 Support synchronous non-call exceptions
1527
1528 fomit-frame-pointer
1529 Common Report Var(flag_omit_frame_pointer) Optimization
1530 When possible do not generate stack frames
1531
1532 foptimize-register-move
1533 Common Report Var(flag_regmove) Optimization
1534 Do the full register move optimization pass
1535
1536 foptimize-sibling-calls
1537 Common Report Var(flag_optimize_sibling_calls) Optimization
1538 Optimize sibling and tail recursive calls
1539
1540 fpartial-inlining
1541 Common Report Var(flag_partial_inlining)
1542 Perform partial inlining
1543
1544 fpre-ipa-mem-report
1545 Common Report Var(pre_ipa_mem_report)
1546 Report on memory allocation before interprocedural optimization
1547
1548 fpost-ipa-mem-report
1549 Common Report Var(post_ipa_mem_report)
1550 Report on memory allocation before interprocedural optimization
1551
1552 fpack-struct
1553 Common Report Var(flag_pack_struct) Optimization
1554 Pack structure members together without holes
1555
1556 fpack-struct=
1557 Common RejectNegative Joined UInteger Optimization
1558 -fpack-struct=<number>  Set initial maximum structure member alignment
1559
1560 fpcc-struct-return
1561 Common Report Var(flag_pcc_struct_return,1) Init(DEFAULT_PCC_STRUCT_RETURN)
1562 Return small aggregates in memory, not registers
1563
1564 fpeel-loops
1565 Common Report Var(flag_peel_loops) Optimization
1566 Perform loop peeling
1567
1568 fpeephole
1569 Common Report Var(flag_no_peephole,0) Optimization
1570 Enable machine specific peephole optimizations
1571
1572 fpeephole2
1573 Common Report Var(flag_peephole2) Optimization
1574 Enable an RTL peephole pass before sched2
1575
1576 fPIC
1577 Common Report Var(flag_pic,2)
1578 Generate position-independent code if possible (large mode)
1579
1580 fPIE
1581 Common Report Var(flag_pie,2)
1582 Generate position-independent code for executables if possible (large mode)
1583
1584 fpic
1585 Common Report Var(flag_pic,1)
1586 Generate position-independent code if possible (small mode)
1587
1588 fpie
1589 Common Report Var(flag_pie,1)
1590 Generate position-independent code for executables if possible (small mode)
1591
1592 fplugin=
1593 Common Joined RejectNegative Var(common_deferred_options) Defer
1594 Specify a plugin to load
1595
1596 fplugin-arg-
1597 Common Joined RejectNegative Var(common_deferred_options) Defer
1598 -fplugin-arg-<name>-<key>[=<value>]     Specify argument <key>=<value> for plugin <name>
1599
1600 fpredictive-commoning
1601 Common Report Var(flag_predictive_commoning) Optimization
1602 Run predictive commoning optimization.
1603
1604 fprefetch-loop-arrays
1605 Common Report Var(flag_prefetch_loop_arrays) Init(-1) Optimization
1606 Generate prefetch instructions, if available, for arrays in loops
1607
1608 fprofile
1609 Common Report Var(profile_flag)
1610 Enable basic program profiling code
1611
1612 fprofile-arcs
1613 Common Report Var(profile_arc_flag)
1614 Insert arc-based program profiling code
1615
1616 fprofile-dir=
1617 Common Joined RejectNegative Var(profile_data_prefix)
1618 Set the top-level directory for storing the profile data.
1619 The default is 'pwd'.
1620
1621 fprofile-correction
1622 Common Report Var(flag_profile_correction)
1623 Enable correction of flow inconsistent profile data input
1624
1625 fprofile-generate
1626 Common
1627 Enable common options for generating profile info for profile feedback directed optimizations
1628
1629 fprofile-generate=
1630 Common Joined RejectNegative
1631 Enable common options for generating profile info for profile feedback directed optimizations, and set -fprofile-dir=
1632
1633 fprofile-use
1634 Common Var(flag_profile_use)
1635 Enable common options for performing profile feedback directed optimizations
1636
1637 fprofile-use=
1638 Common Joined RejectNegative
1639 Enable common options for performing profile feedback directed optimizations, and set -fprofile-dir=
1640
1641 fprofile-values
1642 Common Report Var(flag_profile_values)
1643 Insert code to profile values of expressions
1644
1645 frandom-seed
1646 Common Var(common_deferred_options) Defer
1647
1648 frandom-seed=
1649 Common Joined RejectNegative Var(common_deferred_options) Defer
1650 -frandom-seed=<string>  Make compile reproducible using <string>
1651
1652 ; This switch causes the command line that was used to create an
1653 ; object file to be recorded into the object file.  The exact format
1654 ; of this recording is target and binary file format dependent.
1655 ; It is related to the -fverbose-asm switch, but that switch only
1656 ; records information in the assembler output file as comments, so
1657 ; they never reach the object file.
1658 frecord-gcc-switches
1659 Common Report Var(flag_record_gcc_switches)
1660 Record gcc command line switches in the object file.
1661
1662 freg-struct-return
1663 Common Report Var(flag_pcc_struct_return,0) Optimization
1664 Return small aggregates in registers
1665
1666 fregmove
1667 Common Report Var(flag_regmove) Optimization
1668 Enables a register move optimization
1669
1670 frename-registers
1671 Common Report Var(flag_rename_registers) Init(2) Optimization
1672 Perform a register renaming optimization pass
1673
1674 freorder-blocks
1675 Common Report Var(flag_reorder_blocks) Optimization
1676 Reorder basic blocks to improve code placement
1677
1678 freorder-blocks-and-partition
1679 Common Report Var(flag_reorder_blocks_and_partition) Optimization
1680 Reorder basic blocks and partition into hot and cold sections
1681
1682 freorder-functions
1683 Common Report Var(flag_reorder_functions) Optimization
1684 Reorder functions to improve code placement
1685
1686 frerun-cse-after-loop
1687 Common Report Var(flag_rerun_cse_after_loop) Optimization
1688 Add a common subexpression elimination pass after loop optimizations
1689
1690 frerun-loop-opt
1691 Common Ignore
1692 Does nothing.  Preserved for backward compatibility.
1693
1694 frounding-math
1695 Common Report Var(flag_rounding_math) Optimization SetByCombined
1696 Disable optimizations that assume default FP rounding behavior
1697
1698 fsched-interblock
1699 Common Report Var(flag_schedule_interblock) Init(1) Optimization
1700 Enable scheduling across basic blocks
1701
1702 fsched-pressure
1703 Common Report Var(flag_sched_pressure) Init(0) Optimization
1704 Enable register pressure sensitive insn scheduling
1705
1706 fsched-spec
1707 Common Report Var(flag_schedule_speculative) Init(1) Optimization
1708 Allow speculative motion of non-loads
1709
1710 fsched-spec-load
1711 Common Report Var(flag_schedule_speculative_load) Optimization
1712 Allow speculative motion of some loads
1713
1714 fsched-spec-load-dangerous
1715 Common Report Var(flag_schedule_speculative_load_dangerous) Optimization
1716 Allow speculative motion of more loads
1717
1718 fsched-verbose=
1719 Common RejectNegative Joined UInteger Var(sched_verbose_param)
1720 -fsched-verbose=<number>        Set the verbosity level of the scheduler
1721
1722 fsched2-use-superblocks
1723 Common Report Var(flag_sched2_use_superblocks) Optimization
1724 If scheduling post reload, do superblock scheduling
1725
1726 fsched2-use-traces
1727 Common Ignore
1728 Does nothing.  Preserved for backward compatibility.
1729
1730 fschedule-insns
1731 Common Report Var(flag_schedule_insns) Optimization
1732 Reschedule instructions before register allocation
1733
1734 fschedule-insns2
1735 Common Report Var(flag_schedule_insns_after_reload) Optimization
1736 Reschedule instructions after register allocation
1737
1738 ; This flag should be on when a target implements non-trivial
1739 ; scheduling hooks, maybe saving some information for its own sake.
1740 ; On IA64, for example, this is used for correct bundling.
1741 fselective-scheduling
1742 Common Report Var(flag_selective_scheduling) Optimization
1743 Schedule instructions using selective scheduling algorithm
1744
1745 fselective-scheduling2
1746 Common Report Var(flag_selective_scheduling2) Optimization
1747 Run selective scheduling after reload
1748
1749 fsel-sched-pipelining
1750 Common Report Var(flag_sel_sched_pipelining) Init(0) Optimization
1751 Perform software pipelining of inner loops during selective scheduling
1752
1753 fsel-sched-pipelining-outer-loops
1754 Common Report Var(flag_sel_sched_pipelining_outer_loops) Init(0) Optimization
1755 Perform software pipelining of outer loops during selective scheduling
1756
1757 fsel-sched-reschedule-pipelined
1758 Common Report Var(flag_sel_sched_reschedule_pipelined) Init(0) Optimization
1759 Reschedule pipelined regions without pipelining
1760
1761 ; sched_stalled_insns means that insns can be moved prematurely from the queue
1762 ; of stalled insns into the ready list.
1763 fsched-stalled-insns
1764 Common Report Var(flag_sched_stalled_insns) Optimization UInteger
1765 Allow premature scheduling of queued insns
1766
1767 fsched-stalled-insns=
1768 Common RejectNegative Joined UInteger
1769 -fsched-stalled-insns=<number>  Set number of queued insns that can be prematurely scheduled
1770
1771 ; sched_stalled_insns_dep controls how many recently scheduled cycles will
1772 ; be examined for a dependency on a stalled insn that is candidate for
1773 ; premature removal from the queue of stalled insns into the ready list (has
1774 ; an effect only if the flag 'sched_stalled_insns' is set).
1775 fsched-stalled-insns-dep
1776 Common Report Var(flag_sched_stalled_insns_dep,1) Init(1) Optimization UInteger
1777 Set dependence distance checking in premature scheduling of queued insns
1778
1779 fsched-stalled-insns-dep=
1780 Common RejectNegative Joined UInteger
1781 -fsched-stalled-insns-dep=<number>      Set dependence distance checking in premature scheduling of queued insns
1782
1783 fsched-group-heuristic
1784 Common Report Var(flag_sched_group_heuristic) Init(1) Optimization
1785 Enable the group heuristic in the scheduler
1786
1787 fsched-critical-path-heuristic
1788 Common Report Var(flag_sched_critical_path_heuristic) Init(1) Optimization
1789 Enable the critical path heuristic in the scheduler
1790
1791 fsched-spec-insn-heuristic
1792 Common Report Var(flag_sched_spec_insn_heuristic) Init(1) Optimization
1793 Enable the speculative instruction heuristic in the scheduler
1794
1795 fsched-rank-heuristic
1796 Common Report Var(flag_sched_rank_heuristic) Init(1) Optimization
1797 Enable the rank heuristic in the scheduler
1798
1799 fsched-last-insn-heuristic
1800 Common Report Var(flag_sched_last_insn_heuristic) Init(1) Optimization
1801 Enable the last instruction heuristic in the scheduler
1802
1803 fsched-dep-count-heuristic
1804 Common Report Var(flag_sched_dep_count_heuristic) Init(1) Optimization
1805 Enable the dependent count heuristic in the scheduler
1806
1807 fsection-anchors
1808 Common Report Var(flag_section_anchors) Optimization
1809 Access data in the same section from shared anchor points
1810
1811 fsee
1812 Common Ignore
1813 Does nothing.  Preserved for backward compatibility.
1814
1815 fzee
1816 Common Ignore
1817 Does nothing.  Preserved for backward compatibility.
1818
1819 free
1820 Common Report Var(flag_ree) Init(0)
1821 Turn on Redundant Extensions Elimination pass.
1822
1823 fshow-column
1824 Common Report Var(flag_show_column) Init(1)
1825 Show column numbers in diagnostics, when available.  Default on
1826
1827 fshrink-wrap
1828 Common Report Var(flag_shrink_wrap) Optimization
1829 Emit function prologues only before parts of the function that need it,
1830 rather than at the top of the function.
1831
1832 fsignaling-nans
1833 Common Report Var(flag_signaling_nans) Optimization SetByCombined
1834 Disable optimizations observable by IEEE signaling NaNs
1835
1836 fsigned-zeros
1837 Common Report Var(flag_signed_zeros) Init(1) Optimization SetByCombined
1838 Disable floating point optimizations that ignore the IEEE signedness of zero
1839
1840 fsingle-precision-constant
1841 Common Report Var(flag_single_precision_constant) Optimization
1842 Convert floating point constants to single precision constants
1843
1844 fsplit-ivs-in-unroller
1845 Common Report Var(flag_split_ivs_in_unroller) Init(1) Optimization
1846 Split lifetimes of induction variables when loops are unrolled
1847
1848 fsplit-stack
1849 Common Report Var(flag_split_stack) Init(-1)
1850 Generate discontiguous stack frames
1851
1852 fsplit-wide-types
1853 Common Report Var(flag_split_wide_types) Optimization
1854 Split wide types into independent registers
1855
1856 fvariable-expansion-in-unroller
1857 Common Report Var(flag_variable_expansion_in_unroller) Optimization
1858 Apply variable expansion when loops are unrolled
1859
1860 fstack-check=
1861 Common Report RejectNegative Joined
1862 -fstack-check=[no|generic|specific]     Insert stack checking code into the program
1863
1864 fstack-check
1865 Common Alias(fstack-check=, specific, no)
1866 Insert stack checking code into the program.  Same as -fstack-check=specific
1867
1868 fstack-limit
1869 Common Var(common_deferred_options) Defer
1870
1871 fstack-limit-register=
1872 Common RejectNegative Joined Var(common_deferred_options) Defer
1873 -fstack-limit-register=<register>       Trap if the stack goes past <register>
1874
1875 fstack-limit-symbol=
1876 Common RejectNegative Joined Var(common_deferred_options) Defer
1877 -fstack-limit-symbol=<name>     Trap if the stack goes past symbol <name>
1878
1879 fstack-protector
1880 Common Report Var(flag_stack_protect, 1)
1881 Use propolice as a stack protection method
1882
1883 fstack-protector-all
1884 Common Report RejectNegative Var(flag_stack_protect, 2)
1885 Use a stack protection method for every function
1886
1887 fstack-usage
1888 Common RejectNegative Var(flag_stack_usage)
1889 Output stack usage information on a per-function basis
1890
1891 fstrength-reduce
1892 Common Ignore
1893 Does nothing.  Preserved for backward compatibility.
1894
1895 ; Nonzero if we should do (language-dependent) alias analysis.
1896 ; Typically, this analysis will assume that expressions of certain
1897 ; types do not alias expressions of certain other types.  Only used
1898 ; if alias analysis (in general) is enabled.
1899 fstrict-aliasing
1900 Common Report Var(flag_strict_aliasing) Optimization
1901 Assume strict aliasing rules apply
1902
1903 fstrict-overflow
1904 Common Report Var(flag_strict_overflow)
1905 Treat signed overflow as undefined
1906
1907 fsync-libcalls
1908 Common Report Var(flag_sync_libcalls) Init(1)
1909 Implement __atomic operations via libcalls to legacy __sync functions
1910
1911 fsyntax-only
1912 Common Report Var(flag_syntax_only)
1913 Check for syntax errors, then stop
1914
1915 ftest-coverage
1916 Common Report Var(flag_test_coverage)
1917 Create data files needed by \"gcov\"
1918
1919 fthread-jumps
1920 Common Report Var(flag_thread_jumps) Optimization
1921 Perform jump threading optimizations
1922
1923 ftime-report
1924 Common Report Var(time_report)
1925 Report the time taken by each compiler pass
1926
1927 ftls-model=
1928 Common Joined RejectNegative Enum(tls_model) Var(flag_tls_default) Init(TLS_MODEL_GLOBAL_DYNAMIC)
1929 -ftls-model=[global-dynamic|local-dynamic|initial-exec|local-exec]      Set the default thread-local storage code generation model
1930
1931 Enum
1932 Name(tls_model) Type(enum tls_model) UnknownError(unknown TLS model %qs)
1933
1934 EnumValue
1935 Enum(tls_model) String(global-dynamic) Value(TLS_MODEL_GLOBAL_DYNAMIC)
1936
1937 EnumValue
1938 Enum(tls_model) String(local-dynamic) Value(TLS_MODEL_LOCAL_DYNAMIC)
1939
1940 EnumValue
1941 Enum(tls_model) String(initial-exec) Value(TLS_MODEL_INITIAL_EXEC)
1942
1943 EnumValue
1944 Enum(tls_model) String(local-exec) Value(TLS_MODEL_LOCAL_EXEC)
1945
1946 ftoplevel-reorder
1947 Common Report Var(flag_toplevel_reorder) Init(2) Optimization
1948 Reorder top level functions, variables, and asms
1949
1950 ftracer
1951 Common Report Var(flag_tracer)
1952 Perform superblock formation via tail duplication
1953
1954 ; Zero means that floating-point math operations cannot generate a
1955 ; (user-visible) trap.  This is the case, for example, in nonstop
1956 ; IEEE 754 arithmetic.
1957 ftrapping-math
1958 Common Report Var(flag_trapping_math) Init(1) Optimization SetByCombined
1959 Assume floating-point operations can trap
1960
1961 ftrapv
1962 Common Report Var(flag_trapv) Optimization
1963 Trap for signed overflow in addition, subtraction and multiplication
1964
1965 ftree-ccp
1966 Common Report Var(flag_tree_ccp) Optimization
1967 Enable SSA-CCP optimization on trees
1968
1969 ftree-bit-ccp
1970 Common Report Var(flag_tree_bit_ccp) Optimization
1971 Enable SSA-BIT-CCP optimization on trees
1972
1973 ftree-store-ccp
1974 Common Ignore
1975 Does nothing.  Preserved for backward compatibility.
1976
1977 ftree-ch
1978 Common Report Var(flag_tree_ch) Optimization
1979 Enable loop header copying on trees
1980
1981 ftree-coalesce-inlined-vars
1982 Common Report Var(flag_ssa_coalesce_vars,1) Init(2) RejectNegative Optimization
1983 Enable coalescing of copy-related user variables that are inlined
1984
1985 ftree-coalesce-vars
1986 Common Report Var(flag_ssa_coalesce_vars,2) Optimization
1987 Enable coalescing of all copy-related user variables
1988
1989 ftree-copyrename
1990 Common Report Var(flag_tree_copyrename) Optimization
1991 Replace SSA temporaries with better names in copies
1992
1993 ftree-copy-prop
1994 Common Report Var(flag_tree_copy_prop) Optimization
1995 Enable copy propagation on trees
1996
1997 ftree-store-copy-prop
1998 Common Ignore
1999 Does nothing.  Preserved for backward compatibility.
2000
2001 ftree-cselim
2002 Common Report Var(flag_tree_cselim) Init(2) Optimization
2003 Transform condition stores into unconditional ones
2004
2005 ftree-switch-conversion
2006 Common Report Var(flag_tree_switch_conversion) Optimization
2007 Perform conversions of switch initializations.
2008
2009 ftree-dce
2010 Common Report Var(flag_tree_dce) Optimization
2011 Enable SSA dead code elimination optimization on trees
2012
2013 ftree-dominator-opts
2014 Common Report Var(flag_tree_dom) Optimization
2015 Enable dominator optimizations
2016
2017 ftree-tail-merge
2018 Common Report Var(flag_tree_tail_merge) Optimization
2019 Enable tail merging on trees
2020
2021 ftree-dse
2022 Common Report Var(flag_tree_dse) Optimization
2023 Enable dead store elimination
2024
2025 ftree-forwprop
2026 Common Report Var(flag_tree_forwprop) Init(1) Optimization
2027 Enable forward propagation on trees
2028
2029 ftree-fre
2030 Common Report Var(flag_tree_fre) Optimization
2031 Enable Full Redundancy Elimination (FRE) on trees
2032
2033 foptimize-strlen
2034 Common Report Var(flag_optimize_strlen) Optimization
2035 Enable string length optimizations on trees
2036
2037 ftree-loop-distribution
2038 Common Report Var(flag_tree_loop_distribution) Optimization
2039 Enable loop distribution on trees
2040
2041 ftree-loop-distribute-patterns
2042 Common Report Var(flag_tree_loop_distribute_patterns) Optimization
2043 Enable loop distribution for patterns transformed into a library call
2044
2045 ftree-loop-im
2046 Common Report Var(flag_tree_loop_im) Init(1) Optimization
2047 Enable loop invariant motion on trees
2048
2049 ftree-loop-linear
2050 Common Alias(floop-interchange)
2051 Enable loop interchange transforms.  Same as -floop-interchange
2052
2053 ftree-loop-ivcanon
2054 Common Report Var(flag_tree_loop_ivcanon) Init(1) Optimization
2055 Create canonical induction variables in loops
2056
2057 ftree-loop-optimize
2058 Common Report Var(flag_tree_loop_optimize) Init(1) Optimization
2059 Enable loop optimizations on tree level
2060
2061 ftree-parallelize-loops=
2062 Common Report Joined RejectNegative UInteger Var(flag_tree_parallelize_loops) Init(1)
2063 Enable automatic parallelization of loops
2064
2065 ftree-phiprop
2066 Common Report Var(flag_tree_phiprop) Init(1) Optimization
2067 Enable hoisting loads from conditional pointers.
2068
2069 ftree-pre
2070 Common Report Var(flag_tree_pre) Optimization
2071 Enable SSA-PRE optimization on trees
2072
2073 ftree-partial-pre
2074 Common Report Var(flag_tree_partial_pre) Optimization
2075 In SSA-PRE optimization on trees, enable partial-partial redundancy elimination
2076
2077 ftree-pta
2078 Common Report Var(flag_tree_pta) Init(1) Optimization
2079 Perform function-local points-to analysis on trees.
2080
2081 ftree-reassoc
2082 Common Report Var(flag_tree_reassoc) Init(1) Optimization
2083 Enable reassociation on tree level
2084
2085 ftree-salias
2086 Common Ignore
2087 Does nothing.  Preserved for backward compatibility.
2088
2089 ftree-sink
2090 Common Report Var(flag_tree_sink) Optimization
2091 Enable SSA code sinking on trees
2092
2093 ftree-slsr
2094 Common Report Var(flag_tree_slsr) Optimization
2095 Perform straight-line strength reduction
2096
2097 ftree-sra
2098 Common Report Var(flag_tree_sra) Optimization
2099 Perform scalar replacement of aggregates
2100
2101 ftree-ter
2102 Common Report Var(flag_tree_ter) Optimization
2103 Replace temporary expressions in the SSA->normal pass
2104
2105 ftree-lrs
2106 Common Report Var(flag_tree_live_range_split) Optimization
2107 Perform live range splitting during the SSA->normal pass
2108
2109 ftree-vrp
2110 Common Report Var(flag_tree_vrp) Init(0) Optimization
2111 Perform Value Range Propagation on trees
2112
2113 funit-at-a-time
2114 Common Report Var(flag_unit_at_a_time) Init(1) Optimization
2115 Compile whole compilation unit at a time
2116
2117 funroll-loops
2118 Common Report Var(flag_unroll_loops) Optimization
2119 Perform loop unrolling when iteration count is known
2120
2121 funroll-all-loops
2122 Common Report Var(flag_unroll_all_loops) Optimization
2123 Perform loop unrolling for all loops
2124
2125 ; Nonzero means that loop optimizer may assume that the induction variables
2126 ; that control loops do not overflow and that the loops with nontrivial
2127 ; exit condition are not infinite
2128 funsafe-loop-optimizations
2129 Common Report Var(flag_unsafe_loop_optimizations) Optimization
2130 Allow loop optimizations to assume that the loops behave in normal way
2131
2132 fassociative-math
2133 Common Report Var(flag_associative_math) SetByCombined
2134 Allow optimization for floating-point arithmetic which may change the
2135 result of the operation due to rounding.
2136
2137 freciprocal-math
2138 Common Report Var(flag_reciprocal_math) SetByCombined
2139 Same as -fassociative-math for expressions which include division.
2140
2141 ; Nonzero means that unsafe floating-point math optimizations are allowed
2142 ; for the sake of speed.  IEEE compliance is not guaranteed, and operations
2143 ; are allowed to assume that their arguments and results are "normal"
2144 ; (e.g., nonnegative for SQRT).
2145 funsafe-math-optimizations
2146 Common Report Var(flag_unsafe_math_optimizations) Optimization SetByCombined
2147 Allow math optimizations that may violate IEEE or ISO standards
2148
2149 funswitch-loops
2150 Common Report Var(flag_unswitch_loops) Optimization
2151 Perform loop unswitching
2152
2153 funwind-tables
2154 Common Report Var(flag_unwind_tables) Optimization
2155 Just generate unwind tables for exception handling
2156
2157 fuse-linker-plugin
2158 Common Undocumented
2159
2160 ; Positive if we should track variables, negative if we should run
2161 ; the var-tracking pass only to discard debug annotations, zero if
2162 ; we're not to run it.  When flag_var_tracking == 2 (AUTODETECT_VALUE) it
2163 ; will be set according to optimize, debug_info_level and debug_hooks
2164 ; in process_options ().
2165 fvar-tracking
2166 Common Report Var(flag_var_tracking) Init(2) Optimization
2167 Perform variable tracking
2168
2169 ; Positive if we should track variables at assignments, negative if
2170 ; we should run the var-tracking pass only to discard debug
2171 ; annotations.  When flag_var_tracking_assignments ==
2172 ; AUTODETECT_VALUE it will be set according to flag_var_tracking.
2173 fvar-tracking-assignments
2174 Common Report Var(flag_var_tracking_assignments) Init(2) Optimization
2175 Perform variable tracking by annotating assignments
2176
2177 ; Nonzero if we should toggle flag_var_tracking_assignments after
2178 ; processing options and computing its default.  */
2179 fvar-tracking-assignments-toggle
2180 Common Report Var(flag_var_tracking_assignments_toggle) Optimization
2181 Toggle -fvar-tracking-assignments
2182
2183 fvar-tracking-uninit
2184 Common Report Var(flag_var_tracking_uninit) Optimization
2185 Perform variable tracking and also tag variables that are uninitialized
2186
2187 ftree-vectorize
2188 Common Report Var(flag_tree_vectorize) Optimization
2189 Enable loop vectorization on trees
2190
2191 ftree-slp-vectorize
2192 Common Report Var(flag_tree_slp_vectorize) Init(2) Optimization
2193 Enable basic block vectorization (SLP) on trees
2194
2195 fvect-cost-model
2196 Common Report Var(flag_vect_cost_model) Optimization
2197 Enable use of cost model in vectorization
2198
2199 ftree-vect-loop-version
2200 Common Report Var(flag_tree_vect_loop_version) Init(1) Optimization
2201 Enable loop versioning when doing loop vectorization on trees
2202
2203 ftree-vectorizer-verbose=
2204 Common RejectNegative Joined UInteger
2205 -ftree-vectorizer-verbose=<number>      Set the verbosity level of the vectorizer
2206
2207 ftree-scev-cprop
2208 Common Report Var(flag_tree_scev_cprop) Init(1) Optimization
2209 Enable copy propagation of scalar-evolution information.
2210
2211 ; -fverbose-asm causes extra commentary information to be produced in
2212 ; the generated assembly code (to make it more readable).  This option
2213 ; is generally only of use to those who actually need to read the
2214 ; generated assembly code (perhaps while debugging the compiler itself).
2215 ; -fno-verbose-asm, the default, causes the extra information
2216 ; to not be added and is useful when comparing two assembler files.
2217 fverbose-asm
2218 Common Report Var(flag_verbose_asm)
2219 Add extra commentary to assembler output
2220
2221 fvisibility=
2222 Common Joined RejectNegative Enum(symbol_visibility) Var(default_visibility) Init(VISIBILITY_DEFAULT)
2223 -fvisibility=[default|internal|hidden|protected]        Set the default symbol visibility
2224
2225 Enum
2226 Name(symbol_visibility) Type(enum symbol_visibility) UnknownError(unrecognized visibility value %qs)
2227
2228 EnumValue
2229 Enum(symbol_visibility) String(default) Value(VISIBILITY_DEFAULT)
2230
2231 EnumValue
2232 Enum(symbol_visibility) String(internal) Value(VISIBILITY_INTERNAL)
2233
2234 EnumValue
2235 Enum(symbol_visibility) String(hidden) Value(VISIBILITY_HIDDEN)
2236
2237 EnumValue
2238 Enum(symbol_visibility) String(protected) Value(VISIBILITY_PROTECTED)
2239
2240 fvpt
2241 Common Report Var(flag_value_profile_transformations) Optimization
2242 Use expression value profiles in optimizations
2243
2244 fweb
2245 Common Report Var(flag_web) Init(2) Optimization
2246 Construct webs and split unrelated uses of single variable
2247
2248 ftree-builtin-call-dce
2249 Common Report Var(flag_tree_builtin_call_dce) Init(0) Optimization
2250 Enable conditional dead code elimination for builtin calls
2251
2252 fwhole-program
2253 Common Report Var(flag_whole_program) Init(0) Optimization
2254 Perform whole program optimizations
2255
2256 fwrapv
2257 Common Report Var(flag_wrapv) Optimization
2258 Assume signed arithmetic overflow wraps around
2259
2260 fzero-initialized-in-bss
2261 Common Report Var(flag_zero_initialized_in_bss) Init(1)
2262 Put zero initialized data in the bss section
2263
2264 g
2265 Common JoinedOrMissing
2266 Generate debug information in default format
2267
2268 gcoff
2269 Common JoinedOrMissing Negative(gdwarf-)
2270 Generate debug information in COFF format
2271
2272 gdwarf-
2273 Common Joined UInteger Var(dwarf_version) Init(4) Negative(gstabs)
2274 Generate debug information in DWARF v2 (or later) format
2275
2276 ggdb
2277 Common JoinedOrMissing
2278 Generate debug information in default extended format
2279
2280 gno-pubnames
2281 Common RejectNegative Var(debug_generate_pub_sections, 0) Init(-1)
2282 Don't generate DWARF pubnames and pubtypes sections.
2283
2284 gpubnames
2285 Common RejectNegative Var(debug_generate_pub_sections, 1)
2286 Generate DWARF pubnames and pubtypes sections.
2287
2288 gno-record-gcc-switches
2289 Common RejectNegative Var(dwarf_record_gcc_switches,0) Init(1)
2290 Don't record gcc command line switches in DWARF DW_AT_producer.
2291
2292 grecord-gcc-switches
2293 Common RejectNegative Var(dwarf_record_gcc_switches,1)
2294 Record gcc command line switches in DWARF DW_AT_producer.
2295
2296 gstabs
2297 Common JoinedOrMissing Negative(gstabs+)
2298 Generate debug information in STABS format
2299
2300 gstabs+
2301 Common JoinedOrMissing Negative(gvms)
2302 Generate debug information in extended STABS format
2303
2304 gno-strict-dwarf
2305 Common RejectNegative Var(dwarf_strict,0) Init(0)
2306 Emit DWARF additions beyond selected version
2307
2308 gstrict-dwarf
2309 Common Report RejectNegative Var(dwarf_strict,1)
2310 Don't emit DWARF additions beyond selected version
2311
2312 gtoggle
2313 Common Report Var(flag_gtoggle)
2314 Toggle debug information generation
2315
2316 gvms
2317 Common JoinedOrMissing Negative(gxcoff)
2318 Generate debug information in VMS format
2319
2320 gxcoff
2321 Common JoinedOrMissing Negative(gxcoff+)
2322 Generate debug information in XCOFF format
2323
2324 gxcoff+
2325 Common JoinedOrMissing Negative(gcoff)
2326 Generate debug information in extended XCOFF format
2327
2328 h
2329 Driver Joined Separate
2330
2331 iplugindir=
2332 Common Joined Var(plugindir_string) Init(0)
2333 -iplugindir=<dir>       Set <dir> to be the default plugin directory
2334
2335 l
2336 Driver Joined Separate
2337
2338 n
2339 Driver
2340
2341 no-canonical-prefixes
2342 Driver
2343
2344 nodefaultlibs
2345 Driver
2346
2347 nostartfiles
2348 Driver
2349
2350 nostdlib
2351 Driver
2352
2353 o
2354 Common Driver Joined Separate Var(asm_file_name) MissingArgError(missing filename after %qs)
2355 -o <file>       Place output into <file>
2356
2357 p
2358 Common Var(profile_flag)
2359 Enable function profiling
2360
2361 pass-exit-codes
2362 Driver Var(pass_exit_codes)
2363
2364 pedantic
2365 Common Alias(Wpedantic)
2366
2367 pedantic-errors
2368 Common Var(flag_pedantic_errors)
2369 Like -pedantic but issue them as errors
2370
2371 pg
2372 Driver
2373
2374 pipe
2375 Driver Var(use_pipes)
2376
2377 print-file-name=
2378 Driver JoinedOrMissing Var(print_file_name)
2379
2380 print-libgcc-file-name
2381 Driver
2382
2383 print-multi-directory
2384 Driver Var(print_multi_directory)
2385
2386 print-multi-lib
2387 Driver Var(print_multi_lib)
2388
2389 print-multi-os-directory
2390 Driver Var(print_multi_os_directory)
2391
2392 print-prog-name=
2393 Driver JoinedOrMissing Var(print_prog_name)
2394
2395 print-search-dirs
2396 Driver Var(print_search_dirs)
2397
2398 print-sysroot
2399 Driver Var(print_sysroot)
2400
2401 print-sysroot-headers-suffix
2402 Driver Var(print_sysroot_headers_suffix)
2403
2404 quiet
2405 Common Var(quiet_flag) RejectDriver
2406 Do not display functions compiled or elapsed time
2407
2408 r
2409 Driver
2410
2411 s
2412 Driver
2413
2414 save-temps
2415 Driver
2416
2417 save-temps=
2418 Driver Joined
2419
2420 t
2421 Driver
2422
2423 time
2424 Driver Var(report_times)
2425
2426 time=
2427 Driver JoinedOrMissing
2428
2429 u
2430 Driver Joined Separate
2431
2432 undef
2433 Driver
2434 ; C option, but driver must not handle as "-u ndef".
2435
2436 v
2437 Common Driver Var(verbose_flag)
2438 Enable verbose output
2439
2440 version
2441 Common Var(version_flag) RejectDriver
2442 Display the compiler's version
2443
2444 w
2445 Common Var(inhibit_warnings)
2446 Suppress warnings
2447
2448 wrapper
2449 Driver Separate Var(wrapper_string)
2450
2451 x
2452 Driver Joined Separate
2453
2454 shared
2455 Driver RejectNegative Negative(pie)
2456 Create a shared library
2457
2458 shared-libgcc
2459 Driver
2460
2461 specs
2462 Driver Separate Alias(specs=)
2463
2464 specs=
2465 Driver Joined
2466
2467 static
2468 Driver
2469
2470 static-libgcc
2471 Driver
2472
2473 static-libgfortran
2474 Driver
2475 ; Documented for Fortran, but always accepted by driver.
2476
2477 static-libstdc++
2478 Driver
2479
2480 static-libgo
2481 Driver
2482 ; Documented for Go, but always accepted by driver.
2483
2484 symbolic
2485 Driver
2486
2487 pie
2488 Driver RejectNegative Negative(shared)
2489 Create a position independent executable
2490
2491 z
2492 Driver Joined Separate
2493
2494 ; This comment is to ensure we retain the blank line above.