1 ; Options for the language- and target-independent parts of the compiler.
3 ; Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011
4 ; Free Software Foundation, Inc.
6 ; This file is part of GCC.
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
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
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/>.
22 ; See the GCC internals manual (options.texi) for a description of this file's format.
24 ; Please try to keep this file in ASCII collating order.
35 ; Not used directly to control optimizations, only to save -Ofast
36 ; setting for "optimize" attributes.
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.
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.
51 int flag_complex_method = 1
53 ; Nonzero if subexpressions must be evaluated from left-to-right.
55 int flag_evaluation_order = 0
57 ; Language specific warning pass for unused results.
59 bool flag_warn_unused_result = false
64 ; Nonzero if we should write GIMPLE bytecode for link-time optimization.
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'.
75 HOST_WIDE_INT larger_than_size
77 ; True to warn about any function whose frame size is larger
80 bool warn_frame_larger_than
83 HOST_WIDE_INT frame_larger_than_size
85 ; Nonzero means we should be saving declaration info into a .X file.
87 int flag_gen_aux_info = 0
89 ; Nonzero if we are compiling code for a shared library, zero for
94 ; These two are really VEC(char_p,heap) *.
97 void *flag_instrument_functions_exclude_functions
100 void *flag_instrument_functions_exclude_files
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.
106 ; Structs only handled by reference (indirectly), will also usually
107 ; not need as much debugging information.
110 enum debug_struct_file debug_struct_ordinary[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
113 enum debug_struct_file debug_struct_generic[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
115 ; True if we should exit after parsing options.
117 bool exit_after_options
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.
123 enum debug_info_type write_symbols = NO_DEBUG
125 ; Level of debugging information we are producing. See flag-types.h
126 ; for the definitions of the different possible levels.
128 enum debug_info_levels debug_info_level = DINFO_LEVEL_NONE
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.
134 bool use_gnu_debug_info_extensions
136 ; Original value of maximum field alignment in bytes, specified via
137 ; -fpack-struct=<value>.
139 unsigned int initial_max_fld_align = TARGET_DEFAULT_PACK_STRUCT
142 enum vect_verbosity_levels user_vect_verbosity_level = MAX_VERBOSITY_LEVEL
144 ; Type of stack check.
146 enum stack_check_type flag_stack_check = NO_STACK_CHECK
148 ; True if stack usage information needs to be computed.
150 bool flag_stack_usage_info = false
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.
161 ; -dP causes the rtl to be emitted as a comment in assembly.
163 int flag_dump_rtl_in_asm
165 ; Whether -da was passed (used only in handle_common_deferred_options).
167 bool flag_dump_all_passed
169 ; Other flags saying which kinds of debugging dump have been requested.
172 int rtl_dump_and_exit
175 int flag_print_asm_name
178 enum graph_dump_types graph_dump_format = no_graph
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.
184 const char *main_input_filename
186 ; Pointer to base name in main_input_filename, with directories and a
187 ; single final extension removed, and the length of this base
191 const char *main_input_basename
194 int main_input_baselength
196 ; Which options have been printed by --help.
200 ; Which enums have been printed by --help. 0 = not printed, no
201 ; relevant options seen, 1 = relevant option seen, not yet printed, 2
204 char *help_enum_printed
206 ; The number of columns for --help output.
208 unsigned int help_columns
210 ; Whether this options structure has been through finish_options
212 bool flag_opts_finished
224 Driver Alias(coverage)
230 Common Separate Alias(d)
233 Common Joined Alias(d)
236 Common Separate Alias(dumpbase)
239 Common Separate Alias(dumpdir)
242 Driver Separate Alias(e)
245 Driver Joined Alias(e)
248 Common Warning Alias(Wextra)
251 Driver Separate Alias(Xassembler)
254 Driver JoinedOrMissing Alias(Xassembler)
257 Driver Separate Alias(Xlinker)
260 Driver JoinedOrMissing Alias(Xlinker)
263 Driver Separate Alias(u)
266 Driver Joined Alias(u)
269 Common Driver Var(help_flag)
270 Display this information
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
277 Driver Separate Alias(x)
280 Driver Joined Alias(x)
283 Driver Separate Alias(L)
286 Driver Joined Alias(L)
288 -no-canonical-prefixes
289 Driver Alias(no-canonical-prefixes)
291 -no-standard-libraries
292 Driver Alias(nostdlib)
301 Common Driver Separate Alias(o) MissingArgError(missing filename after %qs)
304 Common Driver Joined Alias(o) MissingArgError(missing filename after %qs)
307 Driver Alias(pass-exit-codes)
310 Common Alias(pedantic)
313 Common Alias(pedantic-errors)
322 Driver Separate Alias(B)
325 Driver JoinedOrMissing Alias(B)
331 Driver Separate Alias(print-file-name=)
334 Driver JoinedOrMissing Alias(print-file-name=)
336 -print-libgcc-file-name
337 Driver Alias(print-libgcc-file-name)
339 -print-multi-directory
340 Driver Alias(print-multi-directory)
343 Driver Alias(print-multi-lib)
345 -print-multi-os-directory
346 Driver Alias(print-multi-os-directory)
349 Driver Separate Alias(print-prog-name=)
352 Driver JoinedOrMissing Alias(print-prog-name=)
355 Driver Alias(print-search-dirs)
358 Driver Alias(print-sysroot)
360 -print-sysroot-headers-suffix
361 Driver Alias(print-sysroot-headers-suffix)
367 Driver Alias(save-temps)
373 Driver Separate Alias(specs=)
376 Driver Joined Alias(specs=)
382 Driver Alias(symbolic)
386 Alias for --help=target
394 ;; The driver used to convert options such as --help into forms such
395 ;; as -fhelp; the following four entries are for compatibility with
396 ;; any direct uses of those (undocumented) -f forms
398 Common Driver Alias(-help)
401 Common Driver Joined Alias(-help=)
404 Common Driver Alias(-target-help)
407 Common Driver Alias(-version)
411 --param <param>=<value> Set parameter <param> to value. See below for a complete list of parameters
414 Common Joined Alias(-param)
417 Driver Separate Alias(-sysroot=)
420 Driver JoinedOrMissing
426 Driver Joined Separate
432 Driver Joined Separate
438 Common JoinedOrMissing Optimization
439 -O<number> Set optimization level to <number>
443 Optimize for space rather than speed
447 Optimize for speed disregarding exact standards compliance
459 Driver Joined Separate
465 Driver Joined Separate
486 Common RejectNegative Warning Alias(Wextra)
487 This switch is deprecated; use -Wextra instead
490 Driver JoinedOrMissing
493 Driver JoinedOrMissing
496 Driver JoinedOrMissing
499 Common Var(warn_aggregate_return) Warning
500 Warn about returning structures, unions or arrays
503 Common Var(warn_array_bounds) Warning
504 Warn if an array is accessed out of bounds
507 Common Var(warn_attributes) Init(1) Warning
508 Warn about inappropriate attribute usage
511 Common Var(warn_cast_align) Warning
512 Warn about pointer casts which increase alignment
515 Common Var(warn_cpp) Init(1) Warning
516 Warn when a #warning directive is encountered
518 Wdeprecated-declarations
519 Common Var(warn_deprecated_decl) Init(1) Warning
520 Warn about uses of __attribute__((deprecated)) declarations
522 Wdisabled-optimization
523 Common Var(warn_disabled_optimization) Warning
524 Warn when an optimization pass is disabled
527 Common Var(warnings_are_errors)
528 Treat all warnings as errors
532 Treat specified warning as error
535 Common Var(extra_warnings) Warning
536 Print extra (possibly unwanted) warnings
539 Common Var(flag_fatal_errors)
540 Exit on the first error occurred
543 Common RejectNegative Joined UInteger
544 -Wframe-larger-than=<number> Warn if a function's stack frame requires more than <number> bytes
547 Common Var(warn_free_nonheap_object) Init(1) Warning
548 Warn when attempting to free a non-heap object
551 Common Var(warn_inline) Warning
552 Warn when an inlined function cannot be inlined
555 Common RejectNegative Joined Warning Undocumented Alias(Wlarger-than=)
558 Common RejectNegative Joined UInteger Warning
559 -Wlarger-than=<number> Warn if an object is larger than <number> bytes
561 Wunsafe-loop-optimizations
562 Common Var(warn_unsafe_loop_optimizations) Warning
563 Warn if the loop cannot be optimized due to nontrivial assumptions.
566 Common Var(warn_missing_noreturn) Warning
567 Warn about functions which might be candidates for __attribute__((noreturn))
570 Common Var(warn_mudflap) Init(1) Warning
571 Warn about constructs not instrumented by -fmudflap
574 Common Var(warn_overflow) Init(1) Warning
575 Warn about overflow in arithmetic expressions
578 Common Var(warn_packed) Warning
579 Warn when the packed attribute has no effect on struct layout
582 Common Var(warn_padded) Warning
583 Warn when padding is required to align structure members
586 Common Var(warn_shadow) Warning
587 Warn when one local variable shadows another
590 Common Var(warn_stack_protect) Warning
591 Warn when not issuing stack smashing protection for some reason
594 Common Joined RejectNegative UInteger Var(warn_stack_usage) Init(-1) Warning
595 Warn if stack usage might be larger than specified amount
599 Warn about code which might break strict aliasing rules
602 Common Joined RejectNegative UInteger Var(warn_strict_aliasing) Init(-1) Warning
603 Warn about code which might break strict aliasing rules
607 Warn about optimizations that assume that signed overflow is undefined
610 Common Joined RejectNegative UInteger Var(warn_strict_overflow) Init(-1) Warning
611 Warn about optimizations that assume that signed overflow is undefined
613 Wsuggest-attribute=const
614 Common Var(warn_suggest_attribute_const) Warning
615 Warn about functions which might be candidates for __attribute__((const))
617 Wsuggest-attribute=pure
618 Common Var(warn_suggest_attribute_pure) Warning
619 Warn about functions which might be candidates for __attribute__((pure))
621 Wsuggest-attribute=noreturn
622 Common Var(warn_suggest_attribute_noreturn) Warning
623 Warn about functions which might be candidates for __attribute__((noreturn))
626 Common Var(warn_switch) Warning
627 Warn about enumerated switches, with no default, missing a case
630 Common Var(warn_switch_default) Warning
631 Warn about enumerated switches missing a \"default:\" statement
634 Common Var(warn_switch_enum) Warning
635 Warn about all enumerated switches missing a specific case
638 Common Var(warn_system_headers) Warning
639 Do not suppress warnings from system headers
642 Common Var(warn_trampolines) Warning
643 Warn whenever a trampoline is generated
646 Common Var(warn_type_limits) Init(-1) Warning
647 Warn if a comparison is always true or always false due to the limited range of the data type
650 Common Var(warn_uninitialized) Init(-1) Warning
651 Warn about uninitialized automatic variables
654 Common Var(warn_maybe_uninitialized) Warning
655 Warn about maybe uninitialized automatic variables
659 Does nothing. Preserved for backward compatibility.
662 Common Var(warn_unused) Init(0) Warning
663 Enable all -Wunused- warnings
665 Wunused-but-set-parameter
666 Common Var(warn_unused_but_set_parameter) Init(-1) Warning
667 Warn when a function parameter is only set, otherwise unused
669 Wunused-but-set-variable
670 Common Var(warn_unused_but_set_variable) Init(-1) Warning
671 Warn when a variable is only set, otherwise unused
674 Common Var(warn_unused_function) Init(-1) Warning
675 Warn when a function is unused
678 Common Var(warn_unused_label) Init(-1) Warning
679 Warn when a label is unused
682 Common Var(warn_unused_parameter) Init(-1) Warning
683 Warn when a function parameter is unused
686 Common Var(warn_unused_value) Init(-1) Warning
687 Warn when an expression value is unused
690 Common Var(warn_unused_variable) Init(-1) Warning
691 Warn when a variable is unused
694 Common Var(warn_coverage_mismatch) Init(1) Warning
695 Warn in case profiles in -fprofile-use do not match
710 Common Separate Var(aux_info_file_name)
711 -aux-info <file> Emit declaration information into <file>
714 Common Joined Alias(aux-info)
717 Common Separate RejectDriver Var(aux_base_name)
720 Common Separate RejectDriver
730 -d<letters> Enable dumps from specific passes of the compiler
733 Common Separate Var(dump_base_name)
734 -dumpbase <file> Set the file basename to be used for dumps
737 Common Separate Var(dump_dir_name)
738 -dumpdir <dir> Set the directory name to be used for dumps
750 Driver Joined Separate
752 ; This option has historically been passed down to the linker by an
753 ; accident of a %{e*} spec, so ensure it continues to be passed down
754 ; as a single option. The supported option for this purpose is
755 ; -rdynamic. See PR 47390.
759 ; The version of the C++ ABI in use. The following values are allowed:
761 ; 0: The version of the ABI believed most conformant with the C++ ABI
762 ; specification. This ABI may change as bugs are discovered and fixed.
763 ; Therefore, 0 will not necessarily indicate the same ABI in different
766 ; 1: The version of the ABI first used in G++ 3.2.
768 ; 2: The version of the ABI first used in G++ 3.4 (and current default).
770 ; 3: The version of the ABI that fixes the missing underscore
771 ; in template non-type arguments of pointer type.
773 ; 4: The version of the ABI that introduces unambiguous mangling of
774 ; vector types. First selectable in G++ 4.5.
776 ; 5: The version of the ABI that ignores attribute const/noreturn
777 ; in function pointer mangling, and corrects mangling of decltype and
778 ; function parameters used in other parameters and the return type.
779 ; First selectable in G++ 4.6.
781 ; 6: The version of the ABI that doesn't promote scoped enums to int.
782 ; First selectable in G++ 4.7.
784 ; Additional positive integers will be assigned as new versions of
785 ; the ABI become the default version of the ABI.
787 Common Joined RejectNegative UInteger Var(flag_abi_version) Init(2)
790 Common Report Var(align_functions,0) Optimization UInteger
791 Align the start of functions
794 Common RejectNegative Joined UInteger Var(align_functions)
797 Common Report Var(align_jumps,0) Optimization UInteger
798 Align labels which are only reached by jumping
801 Common RejectNegative Joined UInteger Var(align_jumps)
804 Common Report Var(align_labels,0) Optimization UInteger
808 Common RejectNegative Joined UInteger Var(align_labels)
811 Common Report Var(align_loops,0) Optimization UInteger
812 Align the start of loops
815 Common RejectNegative Joined UInteger Var(align_loops)
819 Does nothing. Preserved for backward compatibility.
823 Does nothing. Preserved for backward compatibility.
825 fargument-noalias-global
827 Does nothing. Preserved for backward compatibility.
829 fargument-noalias-anything
831 Does nothing. Preserved for backward compatibility.
833 fasynchronous-unwind-tables
834 Common Report Var(flag_asynchronous_unwind_tables) Optimization
835 Generate unwind tables that are exact at each instruction boundary
838 Common Report Var(flag_auto_inc_dec) Init(1)
839 Generate auto-inc/dec instructions
841 ; -fcheck-bounds causes gcc to generate array bounds checks.
842 ; For C, C++ and ObjC: defaults off.
843 ; For Java: defaults to on.
844 ; For Fortran: defaults to off.
846 Common Report Var(flag_bounds_check)
847 Generate code to check bounds before indexing arrays
850 Common Report Var(flag_branch_on_count_reg) Init(1) Optimization
851 Replace add, compare, branch with branch on count register
853 fbranch-probabilities
854 Common Report Var(flag_branch_probabilities) Optimization
855 Use profiling information for branch probabilities
857 fbranch-target-load-optimize
858 Common Report Var(flag_branch_target_load_optimize) Optimization
859 Perform branch target load optimization before prologue / epilogue threading
861 fbranch-target-load-optimize2
862 Common Report Var(flag_branch_target_load_optimize2) Optimization
863 Perform branch target load optimization after prologue / epilogue threading
866 Common Report Var(flag_btr_bb_exclusive) Optimization
867 Restrict target load migration not to re-use registers in any basic block
870 Common Joined RejectNegative Var(common_deferred_options) Defer
871 -fcall-saved-<register> Mark <register> as being preserved across functions
874 Common Joined RejectNegative Var(common_deferred_options) Defer
875 -fcall-used-<register> Mark <register> as being corrupted by function calls
877 ; Nonzero for -fcaller-saves: allocate values in regs that need to
878 ; be saved across function calls, if that produces overall better code.
879 ; Optional now, so people can test it.
881 Common Report Var(flag_caller_saves) Optimization
882 Save registers around function calls
885 Common Report Var(flag_check_data_deps)
886 Compare the results of several data dependence analyzers.
888 fcombine-stack-adjustments
889 Common Report Var(flag_combine_stack_adjustments) Optimization
890 Looks for opportunities to reduce stack adjustments and stack references.
893 Common Report Var(flag_no_common,0) Optimization
894 Do not put uninitialized globals in the common section
898 ; Converted by the driver to -fcompare-debug= options.
901 Common Driver JoinedOrMissing RejectNegative Var(flag_compare_debug_opt)
902 -fcompare-debug[=<opts>] Compile with and without e.g. -gtoggle, and compare the final-insns dump
904 fcompare-debug-second
905 Common Driver RejectNegative Var(flag_compare_debug)
906 Run only the second compilation of -fcompare-debug
909 Common Report Var(flag_compare_elim_after_reload) Optimization
910 Perform comparison elimination after register allocation has finished
913 Common Var(flag_conserve_stack) Optimization
914 Do not perform optimizations increasing noticeably stack usage
917 Common Report Var(flag_cprop_registers) Optimization
918 Perform a register copy-propagation optimization pass
921 Common Report Var(flag_crossjumping) Optimization
922 Perform cross-jumping optimization
925 Common Report Var(flag_cse_follow_jumps) Optimization
926 When running CSE, follow jumps to their targets
930 Does nothing. Preserved for backward compatibility.
933 Common Report Var(flag_cx_limited_range) Optimization SetByCombined
934 Omit range reduction step when performing complex division
937 Common Report Var(flag_cx_fortran_rules) Optimization
938 Complex multiplication and division follow Fortran rules
941 Common Report Var(flag_data_sections) Optimization
942 Place data items into their own section
945 Common Report Var(common_deferred_options) Defer
946 List all available debugging counters with their limits and counts.
949 Common RejectNegative Joined Var(common_deferred_options) Defer
950 -fdbg-cnt=<counter>:<limit>[,<counter>:<limit>,...] Set the debug counter limit.
953 Common Joined RejectNegative Var(common_deferred_options) Defer
954 Map one directory name to another in debug information
957 Common Report Var(flag_debug_types_section) Init(1)
958 Output .debug_types section when using DWARF v4 debuginfo.
960 ; Nonzero for -fdefer-pop: don't pop args after each function call
961 ; instead save them up to pop many calls' args with one insns.
963 Common Report Var(flag_defer_pop) Optimization
964 Defer popping functions args from stack until later
967 Common Report Var(flag_delayed_branch) Optimization
968 Attempt to fill delay slots of branch instructions
970 fdelete-null-pointer-checks
971 Common Report Var(flag_delete_null_pointer_checks) Init(1) Optimization
972 Delete useless null pointer checks
975 Common Report Var(flag_devirtualize) Optimization
976 Try to convert virtual calls to direct ones.
978 fdiagnostics-show-location=
979 Common Joined RejectNegative Enum(diagnostic_prefixing_rule)
980 -fdiagnostics-show-location=[once|every-line] How often to emit source location at the beginning of line-wrapped diagnostics
982 ; Required for these enum values.
987 Name(diagnostic_prefixing_rule) Type(int)
990 Enum(diagnostic_prefixing_rule) String(once) Value(DIAGNOSTICS_SHOW_PREFIX_ONCE)
993 Enum(diagnostic_prefixing_rule) String(every-line) Value(DIAGNOSTICS_SHOW_PREFIX_EVERY_LINE)
995 fdiagnostics-show-option
996 Common Var(flag_diagnostics_show_option) Init(1)
997 Amend appropriate diagnostic messages with the command line option that controls them
1000 Common Joined RejectNegative Var(common_deferred_options) Defer
1001 -fdisable-[tree|rtl|ipa]-<pass>=range1+range2 disables an optimization pass
1004 Common Joined RejectNegative Var(common_deferred_options) Defer
1005 -fenable-[tree|rtl|ipa]-<pass>=range1+range2 enables an optimization pass
1008 Common Joined RejectNegative Var(common_deferred_options) Defer
1009 -fdump-<type> Dump various compiler internals to a file
1012 Driver RejectNegative
1015 Common RejectNegative Joined Var(flag_dump_final_insns)
1016 -fdump-final-insns=filename Dump to filename the insns at the end of translation
1019 Common RejectNegative Joined Var(flag_dump_go_spec)
1020 -fdump-go-spec=filename Write all declarations to file as Go code
1023 Common Report Var(flag_dump_noaddr)
1024 Suppress output of addresses in debugging dumps
1027 Common Var(flag_dump_passes) Init(0)
1028 Dump optimization passes
1031 Common Report Var(flag_dump_unnumbered)
1032 Suppress output of instruction numbers, line number notes and addresses in debugging dumps
1034 fdump-unnumbered-links
1035 Common Report Var(flag_dump_unnumbered_links)
1036 Suppress output of previous and next insn numbers in debugging dumps
1039 Common Report Var(flag_dwarf2_cfi_asm) Init(HAVE_GAS_CFI_DIRECTIVE)
1040 Enable CFI tables via GAS assembler directives.
1043 Common Report Var(flag_early_inlining) Init(1) Optimization
1044 Perform early inlining
1046 feliminate-dwarf2-dups
1047 Common Report Var(flag_eliminate_dwarf2_dups)
1048 Perform DWARF2 duplicate elimination
1051 Common Report Var(flag_ipa_sra) Init(0) Optimization
1052 Perform interprocedural reduction of aggregates
1054 feliminate-unused-debug-symbols
1055 Common Report Var(flag_debug_only_used_symbols)
1056 Perform unused type elimination in debug info
1058 feliminate-unused-debug-types
1059 Common Report Var(flag_eliminate_unused_debug_types) Init(1)
1060 Perform unused type elimination in debug info
1062 femit-class-debug-always
1063 Common Report Var(flag_emit_class_debug_always) Init(0)
1064 Do not suppress C++ class debug information.
1067 Common Report Var(flag_exceptions) Optimization
1068 Enable exception handling
1070 fexpensive-optimizations
1071 Common Report Var(flag_expensive_optimizations) Optimization
1072 Perform a number of minor, expensive optimizations
1075 Common Joined RejectNegative Enum(excess_precision) Var(flag_excess_precision_cmdline) Init(EXCESS_PRECISION_DEFAULT)
1076 -fexcess-precision=[fast|standard] Specify handling of excess floating-point precision
1079 Name(excess_precision) Type(enum excess_precision) UnknownError(unknown excess precision style %qs)
1082 Enum(excess_precision) String(fast) Value(EXCESS_PRECISION_FAST)
1085 Enum(excess_precision) String(standard) Value(EXCESS_PRECISION_STANDARD)
1091 Common Var(flag_fat_lto_objects) Init(1)
1092 Output lto objects containing both the intermediate language and binary output.
1095 Common Report Var(flag_finite_math_only) Optimization SetByCombined
1096 Assume no NaNs or infinities are generated
1099 Common Joined RejectNegative Var(common_deferred_options) Defer
1100 -ffixed-<register> Mark <register> as being unavailable to the compiler
1103 Common Report Var(flag_float_store) Optimization
1104 Don't allocate floats and doubles in extended-precision registers
1108 Does nothing. Preserved for backward compatibility.
1111 Common Report Var(flag_forward_propagate) Optimization
1112 Perform a forward propagation pass on RTL
1115 Common Joined RejectNegative Enum(fp_contract_mode) Var(flag_fp_contract_mode) Init(FP_CONTRACT_FAST)
1116 -ffp-contract=[off|on|fast] Perform floating-point expression contraction.
1119 Name(fp_contract_mode) Type(enum fp_contract_mode) UnknownError(unknown floating point contraction style %qs)
1122 Enum(fp_contract_mode) String(off) Value(FP_CONTRACT_OFF)
1124 ; Not implemented, fall back to conservative FP_CONTRACT_OFF.
1126 Enum(fp_contract_mode) String(on) Value(FP_CONTRACT_OFF)
1129 Enum(fp_contract_mode) String(fast) Value(FP_CONTRACT_FAST)
1131 ; Nonzero means don't put addresses of constant functions in registers.
1132 ; Used for compiling the Unix kernel, where strange substitutions are
1133 ; done on the assembly output.
1135 Common Report Var(flag_no_function_cse,0)
1136 Allow function addresses to be held in registers
1139 Common Report Var(flag_function_sections)
1140 Place each function into its own section
1143 Common Report Var(flag_gcse) Optimization
1144 Perform global common subexpression elimination
1147 Common Report Var(flag_gcse_lm) Init(1) Optimization
1148 Perform enhanced load motion during global common subexpression elimination
1151 Common Report Var(flag_gcse_sm) Init(0) Optimization
1152 Perform store motion after global common subexpression elimination
1155 Common Report Var(flag_gcse_las) Init(0) Optimization
1156 Perform redundant load after store elimination in global common subexpression
1160 Common Report Var(flag_gcse_after_reload) Optimization
1161 Perform global common subexpression elimination after register allocation
1164 ; This option is not documented yet as its semantics will change.
1166 Common Report Var(flag_graphite)
1167 Enable in and out of Graphite representation
1170 Common Report Var(flag_graphite_identity) Optimization
1171 Enable Graphite Identity transformation
1173 floop-parallelize-all
1174 Common Report Var(flag_loop_parallelize_all) Optimization
1175 Mark all loops as parallel
1178 Common Report Var(flag_loop_strip_mine) Optimization
1179 Enable Loop Strip Mining transformation
1182 Common Report Var(flag_loop_interchange) Optimization
1183 Enable Loop Interchange transformation
1186 Common Report Var(flag_loop_block) Optimization
1187 Enable Loop Blocking transformation
1190 Common Report Var(flag_loop_flatten) Optimization
1191 Enable Loop Flattening transformation
1193 fstrict-volatile-bitfields
1194 Common Report Var(flag_strict_volatile_bitfields) Init(-1)
1195 Force bitfield accesses to match their type width
1197 fguess-branch-probability
1198 Common Report Var(flag_guess_branch_prob) Optimization
1199 Enable guessing of branch probabilities
1201 ; Nonzero means ignore `#ident' directives. 0 means handle them.
1202 ; Generate position-independent code for executables if possible
1203 ; On SVR4 targets, it also controls whether or not to emit a
1204 ; string identifying the compiler.
1206 Common Report Var(flag_no_ident,0)
1207 Process #ident directives
1210 Common Report Var(flag_if_conversion) Optimization
1211 Perform conversion of conditional jumps to branchless equivalents
1214 Common Report Var(flag_if_conversion2) Optimization
1215 Perform conversion of conditional jumps to conditional execution
1217 ftree-loop-if-convert
1218 Common Report Var(flag_tree_loop_if_convert) Init(-1) Optimization
1219 Convert conditional jumps in innermost loops to branchless equivalents
1221 ftree-loop-if-convert-stores
1222 Common Report Var(flag_tree_loop_if_convert_stores) Optimization
1223 Also if-convert conditional jumps containing memory writes
1225 ; -finhibit-size-directive inhibits output of .size for ELF.
1226 ; This is used only for compiling crtstuff.c,
1227 ; and it may be extended to other effects
1228 ; needed for crtstuff.c on other systems.
1229 finhibit-size-directive
1230 Common Report Var(flag_inhibit_size_directive)
1231 Do not generate .size directives
1234 Common Report Var(flag_indirect_inlining)
1235 Perform indirect inlining
1237 ; Nonzero means that functions declared `inline' will be treated
1238 ; as `static'. Prevents generation of zillions of copies of unused
1239 ; static inline functions; instead, `inlines' are written out
1240 ; only when actually used. Used in conjunction with -g. Also
1241 ; does the right thing with #pragma interface.
1243 Common Report Var(flag_no_inline,0) Init(0)
1244 Pay attention to the \"inline\" keyword
1246 finline-small-functions
1247 Common Report Var(flag_inline_small_functions) Optimization
1248 Integrate simple functions into their callers when code size is known to not growth
1251 Common Report Var(flag_inline_functions) Optimization
1252 Integrate simple functions into their callers
1254 finline-functions-called-once
1255 Common Report Var(flag_inline_functions_called_once) Optimization
1256 Integrate functions called once into their callers
1259 Common RejectNegative Joined Alias(finline-limit=)
1262 Common RejectNegative Joined UInteger
1263 -finline-limit=<number> Limit the size of inlined functions to <number>
1265 finstrument-functions
1266 Common Report Var(flag_instrument_function_entry_exit)
1267 Instrument function entry and exit with profiling calls
1269 finstrument-functions-exclude-function-list=
1270 Common RejectNegative Joined
1271 -finstrument-functions-exclude-function-list=name,... Do not instrument listed functions
1273 finstrument-functions-exclude-file-list=
1274 Common RejectNegative Joined
1275 -finstrument-functions-exclude-file-list=filename,... Do not instrument functions listed in files
1278 Common Report Var(flag_ipa_cp) Optimization
1279 Perform Interprocedural constant propagation
1282 Common Report Var(flag_ipa_cp_clone) Optimization
1283 Perform cloning to make Interprocedural constant propagation stronger
1286 Common Report Var(flag_ipa_profile) Init(0) Optimization
1287 Perform interprocedural profile propagation
1290 Common Report Var(flag_ipa_pta) Init(0) Optimization
1291 Perform interprocedural points-to analysis
1294 Common Report Var(flag_ipa_pure_const) Init(0) Optimization
1295 Discover pure and const functions
1298 Common Report Var(flag_ipa_reference) Init(0) Optimization
1299 Discover readonly and non addressable static variables
1302 Common Report Var(flag_ipa_matrix_reorg) Optimization
1303 Perform matrix layout flattening and transposing based
1304 on profiling information.
1308 Does nothing. Preserved for backward compatibility.
1311 Common Joined RejectNegative Enum(ira_algorithm) Var(flag_ira_algorithm) Init(IRA_ALGORITHM_CB)
1312 -fira-algorithm=[CB|priority] Set the used IRA algorithm
1315 Name(ira_algorithm) Type(enum ira_algorithm) UnknownError(unknown IRA algorithm %qs)
1318 Enum(ira_algorithm) String(CB) Value(IRA_ALGORITHM_CB)
1321 Enum(ira_algorithm) String(priority) Value(IRA_ALGORITHM_PRIORITY)
1324 Common Joined RejectNegative Enum(ira_region) Var(flag_ira_region) Init(IRA_REGION_MIXED)
1325 -fira-region=[one|all|mixed] Set regions for IRA
1328 Name(ira_region) Type(enum ira_region) UnknownError(unknown IRA region %qs)
1331 Enum(ira_region) String(one) Value(IRA_REGION_ONE)
1334 Enum(ira_region) String(all) Value(IRA_REGION_ALL)
1337 Enum(ira_region) String(mixed) Value(IRA_REGION_MIXED)
1340 Common Report Var(flag_ira_loop_pressure)
1341 Use IRA based register pressure calculation
1342 in RTL loop optimizations.
1344 fira-share-save-slots
1345 Common Report Var(flag_ira_share_save_slots) Init(1)
1346 Share slots for saving different hard registers.
1348 fira-share-spill-slots
1349 Common Report Var(flag_ira_share_spill_slots) Init(1)
1350 Share stack slots for spilled pseudo-registers.
1353 Common RejectNegative Joined UInteger Var(flag_ira_verbose) Init(5)
1354 -fira-verbose=<number> Control IRA's level of diagnostic messages.
1357 Common Report Var(flag_ivopts) Init(1) Optimization
1358 Optimize induction variables on trees
1361 Common Var(flag_jump_tables) Init(1) Optimization
1362 Use jump tables for sufficiently large switch statements
1364 fkeep-inline-functions
1365 Common Report Var(flag_keep_inline_functions)
1366 Generate code for functions even if they are fully inlined
1369 Common Report Var(flag_keep_static_consts) Init(1)
1370 Emit static const variables even if they are not used
1373 Common Report Var(flag_leading_underscore) Init(-1)
1374 Give external symbols a leading underscore
1378 Does nothing. Preserved for backward compatibility.
1382 Enable link-time optimization.
1385 Common RejectNegative Joined Var(flag_lto)
1386 Link-time optimization with number of parallel jobs or jobserver.
1389 Common Var(flag_lto_partition_1to1)
1390 Partition functions and vars at linktime based on object files they originate from
1392 flto-partition=balanced
1393 Common Var(flag_lto_partition_balanced)
1394 Partition functions and vars at linktime into approximately same sized buckets
1397 Common Var(flag_lto_partition_none)
1398 Disable partioning and streaming
1400 ; The initial value of -1 comes from Z_DEFAULT_COMPRESSION in zlib.h.
1401 flto-compression-level=
1402 Common Joined RejectNegative UInteger Var(flag_lto_compression_level) Init(-1)
1403 -flto-compression-level=<number> Use zlib compression level <number> for IL
1406 Common Report Var(flag_lto_report) Init(0) Optimization
1407 Report various link-time optimization statistics
1410 Common Report Var(flag_errno_math) Init(1) Optimization SetByCombined
1411 Set errno after built-in math functions
1414 Common Joined RejectNegative UInteger Var(flag_max_errors)
1415 -fmax-errors=<number> Maximum number of errors to report
1418 Common Report Var(mem_report)
1419 Report on permanent memory allocation
1421 ; This will attempt to merge constant section constants, if 1 only
1422 ; string constants and constants from constant pool, if 2 also constant
1424 fmerge-all-constants
1425 Common Report Var(flag_merge_constants,2) Init(1) Optimization
1426 Attempt to merge identical constants and constant variables
1429 Common Report Var(flag_merge_constants,1) Optimization
1430 Attempt to merge identical constants across compilation units
1432 fmerge-debug-strings
1433 Common Report Var(flag_merge_debug_strings) Init(1)
1434 Attempt to merge identical debug strings across compilation units
1437 Common RejectNegative Joined UInteger
1438 -fmessage-length=<number> Limit diagnostics to <number> characters per line. 0 suppresses line-wrapping
1441 Common Report Var(flag_modulo_sched) Optimization
1442 Perform SMS based modulo scheduling before the first scheduling pass
1444 fmodulo-sched-allow-regmoves
1445 Common Report Var(flag_modulo_sched_allow_regmoves)
1446 Perform SMS based modulo scheduling with register moves allowed
1448 fmove-loop-invariants
1449 Common Report Var(flag_move_loop_invariants) Init(1) Optimization
1450 Move loop invariant computations out of loops
1453 Common RejectNegative Report Var(flag_mudflap)
1454 Add mudflap bounds-checking instrumentation for single-threaded program
1457 Common RejectNegative Report Var(flag_mudflap,2)
1458 Add mudflap bounds-checking instrumentation for multi-threaded program
1461 Common RejectNegative Report Var(flag_mudflap_ignore_reads)
1462 Ignore read operations when inserting mudflap instrumentation
1465 Common Var(flag_dce) Init(1) Optimization
1466 Use the RTL dead code elimination pass
1469 Common Var(flag_dse) Init(1) Optimization
1470 Use the RTL dead store elimination pass
1472 freschedule-modulo-scheduled-loops
1473 Common Report Var(flag_resched_modulo_sched) Optimization
1474 Enable/Disable the traditional scheduling in loops that already passed modulo scheduling
1476 fnon-call-exceptions
1477 Common Report Var(flag_non_call_exceptions) Optimization
1478 Support synchronous non-call exceptions
1481 Common Report Var(flag_omit_frame_pointer) Optimization
1482 When possible do not generate stack frames
1484 foptimize-register-move
1485 Common Report Var(flag_regmove) Optimization
1486 Do the full register move optimization pass
1488 foptimize-sibling-calls
1489 Common Report Var(flag_optimize_sibling_calls) Optimization
1490 Optimize sibling and tail recursive calls
1493 Common Report Var(flag_partial_inlining)
1494 Perform partial inlining
1497 Common Report Var(pre_ipa_mem_report)
1498 Report on memory allocation before interprocedural optimization
1500 fpost-ipa-mem-report
1501 Common Report Var(post_ipa_mem_report)
1502 Report on memory allocation before interprocedural optimization
1505 Common Report Var(flag_pack_struct) Optimization
1506 Pack structure members together without holes
1509 Common RejectNegative Joined UInteger Optimization
1510 -fpack-struct=<number> Set initial maximum structure member alignment
1513 Common Report Var(flag_pcc_struct_return,1) Init(DEFAULT_PCC_STRUCT_RETURN)
1514 Return small aggregates in memory, not registers
1517 Common Report Var(flag_peel_loops) Optimization
1518 Perform loop peeling
1521 Common Report Var(flag_no_peephole,0) Optimization
1522 Enable machine specific peephole optimizations
1525 Common Report Var(flag_peephole2) Optimization
1526 Enable an RTL peephole pass before sched2
1529 Common Report Var(flag_pic,2)
1530 Generate position-independent code if possible (large mode)
1533 Common Report Var(flag_pie,2)
1534 Generate position-independent code for executables if possible (large mode)
1537 Common Report Var(flag_pic,1)
1538 Generate position-independent code if possible (small mode)
1541 Common Report Var(flag_pie,1)
1542 Generate position-independent code for executables if possible (small mode)
1545 Common Joined RejectNegative Var(common_deferred_options) Defer
1546 Specify a plugin to load
1549 Common Joined RejectNegative Var(common_deferred_options) Defer
1550 -fplugin-arg-<name>-<key>[=<value>] Specify argument <key>=<value> for plugin <name>
1552 fpredictive-commoning
1553 Common Report Var(flag_predictive_commoning) Optimization
1554 Run predictive commoning optimization.
1556 fprefetch-loop-arrays
1557 Common Report Var(flag_prefetch_loop_arrays) Init(-1) Optimization
1558 Generate prefetch instructions, if available, for arrays in loops
1561 Common Report Var(profile_flag)
1562 Enable basic program profiling code
1565 Common Report Var(profile_arc_flag)
1566 Insert arc-based program profiling code
1569 Common Joined RejectNegative Var(profile_data_prefix)
1570 Set the top-level directory for storing the profile data.
1571 The default is 'pwd'.
1574 Common Report Var(flag_profile_correction)
1575 Enable correction of flow inconsistent profile data input
1579 Enable common options for generating profile info for profile feedback directed optimizations
1582 Common Joined RejectNegative
1583 Enable common options for generating profile info for profile feedback directed optimizations, and set -fprofile-dir=
1586 Common Var(flag_profile_use)
1587 Enable common options for performing profile feedback directed optimizations
1590 Common Joined RejectNegative
1591 Enable common options for performing profile feedback directed optimizations, and set -fprofile-dir=
1594 Common Report Var(flag_profile_values)
1595 Insert code to profile values of expressions
1598 Common Var(common_deferred_options) Defer
1601 Common Joined RejectNegative Var(common_deferred_options) Defer
1602 -frandom-seed=<string> Make compile reproducible using <string>
1604 ; This switch causes the command line that was used to create an
1605 ; object file to be recorded into the object file. The exact format
1606 ; of this recording is target and binary file format dependent.
1607 ; It is related to the -fverbose-asm switch, but that switch only
1608 ; records information in the assembler output file as comments, so
1609 ; they never reach the object file.
1610 frecord-gcc-switches
1611 Common Report Var(flag_record_gcc_switches)
1612 Record gcc command line switches in the object file.
1615 Common Report Var(flag_pcc_struct_return,0) Optimization
1616 Return small aggregates in registers
1619 Common Report Var(flag_regmove) Optimization
1620 Enables a register move optimization
1623 Common Report Var(flag_rename_registers) Init(2) Optimization
1624 Perform a register renaming optimization pass
1627 Common Report Var(flag_reorder_blocks) Optimization
1628 Reorder basic blocks to improve code placement
1630 freorder-blocks-and-partition
1631 Common Report Var(flag_reorder_blocks_and_partition) Optimization
1632 Reorder basic blocks and partition into hot and cold sections
1635 Common Report Var(flag_reorder_functions) Optimization
1636 Reorder functions to improve code placement
1638 frerun-cse-after-loop
1639 Common Report Var(flag_rerun_cse_after_loop) Optimization
1640 Add a common subexpression elimination pass after loop optimizations
1644 Does nothing. Preserved for backward compatibility.
1647 Common Report Var(flag_rounding_math) Optimization SetByCombined
1648 Disable optimizations that assume default FP rounding behavior
1651 Common Report Var(flag_schedule_interblock) Init(1) Optimization
1652 Enable scheduling across basic blocks
1655 Common Report Var(flag_sched_pressure) Init(0) Optimization
1656 Enable register pressure sensitive insn scheduling
1659 Common Report Var(flag_schedule_speculative) Init(1) Optimization
1660 Allow speculative motion of non-loads
1663 Common Report Var(flag_schedule_speculative_load) Optimization
1664 Allow speculative motion of some loads
1666 fsched-spec-load-dangerous
1667 Common Report Var(flag_schedule_speculative_load_dangerous) Optimization
1668 Allow speculative motion of more loads
1671 Common RejectNegative Joined UInteger Var(sched_verbose_param)
1672 -fsched-verbose=<number> Set the verbosity level of the scheduler
1674 fsched2-use-superblocks
1675 Common Report Var(flag_sched2_use_superblocks) Optimization
1676 If scheduling post reload, do superblock scheduling
1680 Does nothing. Preserved for backward compatibility.
1683 Common Report Var(flag_schedule_insns) Optimization
1684 Reschedule instructions before register allocation
1687 Common Report Var(flag_schedule_insns_after_reload) Optimization
1688 Reschedule instructions after register allocation
1690 ; This flag should be on when a target implements non-trivial
1691 ; scheduling hooks, maybe saving some information for its own sake.
1692 ; On IA64, for example, this is used for correct bundling.
1693 fselective-scheduling
1694 Common Report Var(flag_selective_scheduling) Optimization
1695 Schedule instructions using selective scheduling algorithm
1697 fselective-scheduling2
1698 Common Report Var(flag_selective_scheduling2) Optimization
1699 Run selective scheduling after reload
1701 fsel-sched-pipelining
1702 Common Report Var(flag_sel_sched_pipelining) Init(0) Optimization
1703 Perform software pipelining of inner loops during selective scheduling
1705 fsel-sched-pipelining-outer-loops
1706 Common Report Var(flag_sel_sched_pipelining_outer_loops) Init(0) Optimization
1707 Perform software pipelining of outer loops during selective scheduling
1709 fsel-sched-reschedule-pipelined
1710 Common Report Var(flag_sel_sched_reschedule_pipelined) Init(0) Optimization
1711 Reschedule pipelined regions without pipelining
1713 ; sched_stalled_insns means that insns can be moved prematurely from the queue
1714 ; of stalled insns into the ready list.
1715 fsched-stalled-insns
1716 Common Report Var(flag_sched_stalled_insns) Optimization UInteger
1717 Allow premature scheduling of queued insns
1719 fsched-stalled-insns=
1720 Common RejectNegative Joined UInteger
1721 -fsched-stalled-insns=<number> Set number of queued insns that can be prematurely scheduled
1723 ; sched_stalled_insns_dep controls how many recently scheduled cycles will
1724 ; be examined for a dependency on a stalled insn that is candidate for
1725 ; premature removal from the queue of stalled insns into the ready list (has
1726 ; an effect only if the flag 'sched_stalled_insns' is set).
1727 fsched-stalled-insns-dep
1728 Common Report Var(flag_sched_stalled_insns_dep,1) Init(1) Optimization UInteger
1729 Set dependence distance checking in premature scheduling of queued insns
1731 fsched-stalled-insns-dep=
1732 Common RejectNegative Joined UInteger
1733 -fsched-stalled-insns-dep=<number> Set dependence distance checking in premature scheduling of queued insns
1735 fsched-group-heuristic
1736 Common Report Var(flag_sched_group_heuristic) Init(1) Optimization
1737 Enable the group heuristic in the scheduler
1739 fsched-critical-path-heuristic
1740 Common Report Var(flag_sched_critical_path_heuristic) Init(1) Optimization
1741 Enable the critical path heuristic in the scheduler
1743 fsched-spec-insn-heuristic
1744 Common Report Var(flag_sched_spec_insn_heuristic) Init(1) Optimization
1745 Enable the speculative instruction heuristic in the scheduler
1747 fsched-rank-heuristic
1748 Common Report Var(flag_sched_rank_heuristic) Init(1) Optimization
1749 Enable the rank heuristic in the scheduler
1751 fsched-last-insn-heuristic
1752 Common Report Var(flag_sched_last_insn_heuristic) Init(1) Optimization
1753 Enable the last instruction heuristic in the scheduler
1755 fsched-dep-count-heuristic
1756 Common Report Var(flag_sched_dep_count_heuristic) Init(1) Optimization
1757 Enable the dependent count heuristic in the scheduler
1760 Common Report Var(flag_section_anchors) Optimization
1761 Access data in the same section from shared anchor points
1765 Does nothing. Preserved for backward compatibility.
1768 Common Report Var(flag_zee) Init(0)
1769 Eliminate redundant zero extensions on targets that support implicit extensions.
1772 Common Report Var(flag_show_column) Init(1)
1773 Show column numbers in diagnostics, when available. Default on
1776 Common Report Var(flag_shrink_wrap) Optimization
1777 Emit function prologues only before parts of the function that need it,
1778 rather than at the top of the function.
1781 Common Report Var(flag_signaling_nans) Optimization SetByCombined
1782 Disable optimizations observable by IEEE signaling NaNs
1785 Common Report Var(flag_signed_zeros) Init(1) Optimization SetByCombined
1786 Disable floating point optimizations that ignore the IEEE signedness of zero
1788 fsingle-precision-constant
1789 Common Report Var(flag_single_precision_constant) Optimization
1790 Convert floating point constants to single precision constants
1792 fsplit-ivs-in-unroller
1793 Common Report Var(flag_split_ivs_in_unroller) Init(1) Optimization
1794 Split lifetimes of induction variables when loops are unrolled
1797 Common Report Var(flag_split_stack) Init(-1)
1798 Generate discontiguous stack frames
1801 Common Report Var(flag_split_wide_types) Optimization
1802 Split wide types into independent registers
1804 fvariable-expansion-in-unroller
1805 Common Report Var(flag_variable_expansion_in_unroller) Optimization
1806 Apply variable expansion when loops are unrolled
1809 Common Report RejectNegative Joined
1810 -fstack-check=[no|generic|specific] Insert stack checking code into the program
1813 Common Alias(fstack-check=, specific, no)
1814 Insert stack checking code into the program. Same as -fstack-check=specific
1817 Common Var(common_deferred_options) Defer
1819 fstack-limit-register=
1820 Common RejectNegative Joined Var(common_deferred_options) Defer
1821 -fstack-limit-register=<register> Trap if the stack goes past <register>
1823 fstack-limit-symbol=
1824 Common RejectNegative Joined Var(common_deferred_options) Defer
1825 -fstack-limit-symbol=<name> Trap if the stack goes past symbol <name>
1828 Common Report Var(flag_stack_protect, 1)
1829 Use propolice as a stack protection method
1831 fstack-protector-all
1832 Common Report RejectNegative Var(flag_stack_protect, 2)
1833 Use a stack protection method for every function
1836 Common RejectNegative Var(flag_stack_usage)
1837 Output stack usage information on a per-function basis
1841 Does nothing. Preserved for backward compatibility.
1843 ; Nonzero if we should do (language-dependent) alias analysis.
1844 ; Typically, this analysis will assume that expressions of certain
1845 ; types do not alias expressions of certain other types. Only used
1846 ; if alias analysis (in general) is enabled.
1848 Common Report Var(flag_strict_aliasing) Optimization
1849 Assume strict aliasing rules apply
1852 Common Report Var(flag_strict_overflow)
1853 Treat signed overflow as undefined
1856 Common Report Var(flag_syntax_only)
1857 Check for syntax errors, then stop
1860 Common Report Var(flag_test_coverage)
1861 Create data files needed by \"gcov\"
1864 Common Report Var(flag_thread_jumps) Optimization
1865 Perform jump threading optimizations
1868 Common Report Var(time_report)
1869 Report the time taken by each compiler pass
1872 Common Joined RejectNegative Enum(tls_model) Var(flag_tls_default) Init(TLS_MODEL_GLOBAL_DYNAMIC)
1873 -ftls-model=[global-dynamic|local-dynamic|initial-exec|local-exec] Set the default thread-local storage code generation model
1876 Name(tls_model) Type(enum tls_model) UnknownError(unknown TLS model %qs)
1879 Enum(tls_model) String(global-dynamic) Value(TLS_MODEL_GLOBAL_DYNAMIC)
1882 Enum(tls_model) String(local-dynamic) Value(TLS_MODEL_LOCAL_DYNAMIC)
1885 Enum(tls_model) String(initial-exec) Value(TLS_MODEL_INITIAL_EXEC)
1888 Enum(tls_model) String(local-exec) Value(TLS_MODEL_LOCAL_EXEC)
1891 Common Report Var(flag_toplevel_reorder) Init(2) Optimization
1892 Reorder top level functions, variables, and asms
1895 Common Report Var(flag_tracer)
1896 Perform superblock formation via tail duplication
1898 ; Zero means that floating-point math operations cannot generate a
1899 ; (user-visible) trap. This is the case, for example, in nonstop
1900 ; IEEE 754 arithmetic.
1902 Common Report Var(flag_trapping_math) Init(1) Optimization SetByCombined
1903 Assume floating-point operations can trap
1906 Common Report Var(flag_trapv) Optimization
1907 Trap for signed overflow in addition, subtraction and multiplication
1910 Common Report Var(flag_tree_ccp) Optimization
1911 Enable SSA-CCP optimization on trees
1914 Common Report Var(flag_tree_bit_ccp) Optimization
1915 Enable SSA-BIT-CCP optimization on trees
1919 Does nothing. Preserved for backward compatibility.
1922 Common Report Var(flag_tree_ch) Optimization
1923 Enable loop header copying on trees
1926 Common Report Var(flag_tree_copyrename) Optimization
1927 Replace SSA temporaries with better names in copies
1930 Common Report Var(flag_tree_copy_prop) Optimization
1931 Enable copy propagation on trees
1933 ftree-store-copy-prop
1935 Does nothing. Preserved for backward compatibility.
1938 Common Report Var(flag_tree_cselim) Init(2) Optimization
1939 Transform condition stores into unconditional ones
1941 ftree-switch-conversion
1942 Common Report Var(flag_tree_switch_conversion) Optimization
1943 Perform conversions of switch initializations.
1946 Common Report Var(flag_tree_dce) Optimization
1947 Enable SSA dead code elimination optimization on trees
1949 ftree-dominator-opts
1950 Common Report Var(flag_tree_dom) Optimization
1951 Enable dominator optimizations
1954 Common Report Var(flag_tree_tail_merge) Optimization
1955 Enable tail merging on trees
1958 Common Report Var(flag_tree_dse) Optimization
1959 Enable dead store elimination
1962 Common Report Var(flag_tree_forwprop) Init(1) Optimization
1963 Enable forward propagation on trees
1966 Common Report Var(flag_tree_fre) Optimization
1967 Enable Full Redundancy Elimination (FRE) on trees
1970 Common Report Var(flag_optimize_strlen) Optimization
1971 Enable string length optimizations on trees
1973 ftree-loop-distribution
1974 Common Report Var(flag_tree_loop_distribution) Optimization
1975 Enable loop distribution on trees
1977 ftree-loop-distribute-patterns
1978 Common Report Var(flag_tree_loop_distribute_patterns) Optimization
1979 Enable loop distribution for patterns transformed into a library call
1982 Common Report Var(flag_tree_loop_im) Init(1) Optimization
1983 Enable loop invariant motion on trees
1986 Common Alias(floop-interchange)
1987 Enable loop interchange transforms. Same as -floop-interchange
1990 Common Report Var(flag_tree_loop_ivcanon) Init(1) Optimization
1991 Create canonical induction variables in loops
1994 Common Report Var(flag_tree_loop_optimize) Init(1) Optimization
1995 Enable loop optimizations on tree level
1997 ftree-parallelize-loops=
1998 Common Report Joined RejectNegative UInteger Var(flag_tree_parallelize_loops) Init(1)
1999 Enable automatic parallelization of loops
2002 Common Report Var(flag_tree_phiprop) Init(1) Optimization
2003 Enable hoisting loads from conditional pointers.
2006 Common Report Var(flag_tree_pre) Optimization
2007 Enable SSA-PRE optimization on trees
2010 Common Report Var(flag_tree_pta) Init(1) Optimization
2011 Perform function-local points-to analysis on trees.
2014 Common Report Var(flag_tree_reassoc) Init(1) Optimization
2015 Enable reassociation on tree level
2019 Does nothing. Preserved for backward compatibility.
2022 Common Report Var(flag_tree_sink) Optimization
2023 Enable SSA code sinking on trees
2026 Common Report Var(flag_tree_sra) Optimization
2027 Perform scalar replacement of aggregates
2030 Common Report Var(flag_tree_ter) Optimization
2031 Replace temporary expressions in the SSA->normal pass
2034 Common Report Var(flag_tree_live_range_split) Optimization
2035 Perform live range splitting during the SSA->normal pass
2038 Common Report Var(flag_tree_vrp) Init(0) Optimization
2039 Perform Value Range Propagation on trees
2042 Common Report Var(flag_unit_at_a_time) Init(1) Optimization
2043 Compile whole compilation unit at a time
2046 Common Report Var(flag_unroll_loops) Optimization
2047 Perform loop unrolling when iteration count is known
2050 Common Report Var(flag_unroll_all_loops) Optimization
2051 Perform loop unrolling for all loops
2053 ; Nonzero means that loop optimizer may assume that the induction variables
2054 ; that control loops do not overflow and that the loops with nontrivial
2055 ; exit condition are not infinite
2056 funsafe-loop-optimizations
2057 Common Report Var(flag_unsafe_loop_optimizations) Optimization
2058 Allow loop optimizations to assume that the loops behave in normal way
2061 Common Report Var(flag_associative_math) SetByCombined
2062 Allow optimization for floating-point arithmetic which may change the
2063 result of the operation due to rounding.
2066 Common Report Var(flag_reciprocal_math) SetByCombined
2067 Same as -fassociative-math for expressions which include division.
2069 ; Nonzero means that unsafe floating-point math optimizations are allowed
2070 ; for the sake of speed. IEEE compliance is not guaranteed, and operations
2071 ; are allowed to assume that their arguments and results are "normal"
2072 ; (e.g., nonnegative for SQRT).
2073 funsafe-math-optimizations
2074 Common Report Var(flag_unsafe_math_optimizations) Optimization SetByCombined
2075 Allow math optimizations that may violate IEEE or ISO standards
2078 Common Report Var(flag_unswitch_loops) Optimization
2079 Perform loop unswitching
2082 Common Report Var(flag_unwind_tables) Optimization
2083 Just generate unwind tables for exception handling
2088 ; Positive if we should track variables, negative if we should run
2089 ; the var-tracking pass only to discard debug annotations, zero if
2090 ; we're not to run it. When flag_var_tracking == 2 (AUTODETECT_VALUE) it
2091 ; will be set according to optimize, debug_info_level and debug_hooks
2092 ; in process_options ().
2094 Common Report Var(flag_var_tracking) Init(2) Optimization
2095 Perform variable tracking
2097 ; Positive if we should track variables at assignments, negative if
2098 ; we should run the var-tracking pass only to discard debug
2099 ; annotations. When flag_var_tracking_assignments ==
2100 ; AUTODETECT_VALUE it will be set according to flag_var_tracking.
2101 fvar-tracking-assignments
2102 Common Report Var(flag_var_tracking_assignments) Init(2) Optimization
2103 Perform variable tracking by annotating assignments
2105 ; Nonzero if we should toggle flag_var_tracking_assignments after
2106 ; processing options and computing its default. */
2107 fvar-tracking-assignments-toggle
2108 Common Report Var(flag_var_tracking_assignments_toggle) Optimization
2109 Toggle -fvar-tracking-assignments
2111 fvar-tracking-uninit
2112 Common Report Var(flag_var_tracking_uninit) Optimization
2113 Perform variable tracking and also tag variables that are uninitialized
2116 Common Report Var(flag_tree_vectorize) Optimization
2117 Enable loop vectorization on trees
2120 Common Report Var(flag_tree_slp_vectorize) Init(2) Optimization
2121 Enable basic block vectorization (SLP) on trees
2124 Common Report Var(flag_vect_cost_model) Optimization
2125 Enable use of cost model in vectorization
2127 ftree-vect-loop-version
2128 Common Report Var(flag_tree_vect_loop_version) Init(1) Optimization
2129 Enable loop versioning when doing loop vectorization on trees
2131 ftree-vectorizer-verbose=
2132 Common RejectNegative Joined UInteger
2133 -ftree-vectorizer-verbose=<number> Set the verbosity level of the vectorizer
2136 Common Report Var(flag_tree_scev_cprop) Init(1) Optimization
2137 Enable copy propagation of scalar-evolution information.
2139 ; -fverbose-asm causes extra commentary information to be produced in
2140 ; the generated assembly code (to make it more readable). This option
2141 ; is generally only of use to those who actually need to read the
2142 ; generated assembly code (perhaps while debugging the compiler itself).
2143 ; -fno-verbose-asm, the default, causes the extra information
2144 ; to not be added and is useful when comparing two assembler files.
2146 Common Report Var(flag_verbose_asm)
2147 Add extra commentary to assembler output
2150 Common Joined RejectNegative Enum(symbol_visibility) Var(default_visibility) Init(VISIBILITY_DEFAULT)
2151 -fvisibility=[default|internal|hidden|protected] Set the default symbol visibility
2154 Name(symbol_visibility) Type(enum symbol_visibility) UnknownError(unrecognized visibility value %qs)
2157 Enum(symbol_visibility) String(default) Value(VISIBILITY_DEFAULT)
2160 Enum(symbol_visibility) String(internal) Value(VISIBILITY_INTERNAL)
2163 Enum(symbol_visibility) String(hidden) Value(VISIBILITY_HIDDEN)
2166 Enum(symbol_visibility) String(protected) Value(VISIBILITY_PROTECTED)
2169 Common Report Var(flag_value_profile_transformations) Optimization
2170 Use expression value profiles in optimizations
2173 Common Report Var(flag_web) Init(2) Optimization
2174 Construct webs and split unrelated uses of single variable
2176 ftree-builtin-call-dce
2177 Common Report Var(flag_tree_builtin_call_dce) Init(0) Optimization
2178 Enable conditional dead code elimination for builtin calls
2181 Common Report Var(flag_whole_program) Init(0) Optimization
2182 Perform whole program optimizations
2185 Common Report Var(flag_wrapv) Optimization
2186 Assume signed arithmetic overflow wraps around
2188 fzero-initialized-in-bss
2189 Common Report Var(flag_zero_initialized_in_bss) Init(1)
2190 Put zero initialized data in the bss section
2193 Common JoinedOrMissing
2194 Generate debug information in default format
2197 Common JoinedOrMissing Negative(gdwarf-)
2198 Generate debug information in COFF format
2201 Common Joined UInteger Var(dwarf_version) Init(2) Negative(gstabs)
2202 Generate debug information in DWARF v2 (or later) format
2205 Common JoinedOrMissing
2206 Generate debug information in default extended format
2208 gno-record-gcc-switches
2209 Common RejectNegative Var(dwarf_record_gcc_switches,0) Init(0)
2210 Don't record gcc command line switches in DWARF DW_AT_producer.
2212 grecord-gcc-switches
2213 Common RejectNegative Var(dwarf_record_gcc_switches,1)
2214 Record gcc command line switches in DWARF DW_AT_producer.
2217 Common JoinedOrMissing Negative(gstabs+)
2218 Generate debug information in STABS format
2221 Common JoinedOrMissing Negative(gvms)
2222 Generate debug information in extended STABS format
2225 Common RejectNegative Var(dwarf_strict,0) Init(-1)
2226 Emit DWARF additions beyond selected version
2229 Common Report RejectNegative Var(dwarf_strict,1)
2230 Don't emit DWARF additions beyond selected version
2233 Common Report Var(flag_gtoggle)
2234 Toggle debug information generation
2237 Common JoinedOrMissing Negative(gxcoff)
2238 Generate debug information in VMS format
2241 Common JoinedOrMissing Negative(gxcoff+)
2242 Generate debug information in XCOFF format
2245 Common JoinedOrMissing Negative(gcoff)
2246 Generate debug information in extended XCOFF format
2249 Driver Joined Separate
2252 Common Joined Var(plugindir_string) Init(0)
2253 -iplugindir=<dir> Set <dir> to be the default plugin directory
2256 Driver Joined Separate
2261 no-canonical-prefixes
2274 Common Driver Joined Separate Var(asm_file_name) MissingArgError(missing filename after %qs)
2275 -o <file> Place output into <file>
2278 Common Var(profile_flag)
2279 Enable function profiling
2282 Driver Var(pass_exit_codes)
2285 Common Var(pedantic)
2286 Issue warnings needed for strict compliance to the standard
2289 Common Var(flag_pedantic_errors)
2290 Like -pedantic but issue them as errors
2296 Driver Var(use_pipes)
2299 Driver JoinedOrMissing Var(print_file_name)
2301 print-libgcc-file-name
2304 print-multi-directory
2305 Driver Var(print_multi_directory)
2308 Driver Var(print_multi_lib)
2310 print-multi-os-directory
2311 Driver Var(print_multi_os_directory)
2314 Driver JoinedOrMissing Var(print_prog_name)
2317 Driver Var(print_search_dirs)
2320 Driver Var(print_sysroot)
2322 print-sysroot-headers-suffix
2323 Driver Var(print_sysroot_headers_suffix)
2326 Common Var(quiet_flag) RejectDriver
2327 Do not display functions compiled or elapsed time
2345 Driver Var(report_times)
2348 Driver JoinedOrMissing
2351 Driver Joined Separate
2355 ; C option, but driver must not handle as "-u ndef".
2358 Common Driver Var(verbose_flag)
2359 Enable verbose output
2362 Common Var(version_flag) RejectDriver
2363 Display the compiler's version
2366 Common Var(inhibit_warnings)
2370 Driver Separate Var(wrapper_string)
2373 Driver Joined Separate
2376 Common RejectNegative Negative(pie)
2377 Create a shared library
2383 Driver Separate Alias(specs=)
2396 ; Documented for Fortran, but always accepted by driver.
2403 ; Documented for Go, but always accepted by driver.
2409 Common RejectNegative Negative(shared)
2410 Create a position independent executable
2413 Driver Joined Separate
2415 ; This comment is to ensure we retain the blank line above.