1 ; Options for the language- and target-independent parts of the compiler.
3 ; Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012
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.
38 ; Not used directly to control optimizations, only to save -Ofast
39 ; setting for "optimize" attributes.
43 ; True if this is the lto front end. This is used to disable gimple
44 ; generation and lowering passes that are normally run on the output
45 ; of a front end. These passes must be bypassed for lto since they
46 ; have already been done before the gimple was written.
50 ; 0 means straightforward implementation of complex divide acceptable.
51 ; 1 means wide ranges of inputs must work for complex divide.
52 ; 2 means C99-like requirements for complex multiply and divide.
54 int flag_complex_method = 1
56 ; Nonzero if subexpressions must be evaluated from left-to-right.
58 int flag_evaluation_order = 0
60 ; Language specific warning pass for unused results.
62 bool flag_warn_unused_result = false
67 ; Nonzero if we should write GIMPLE bytecode for link-time optimization.
71 ; True to warn about any objects definitions whose size is larger
72 ; than N bytes. Also want about function definitions whose returned
73 ; values are larger than N bytes, where N is 'larger_than_size'.
78 HOST_WIDE_INT larger_than_size
80 ; True to warn about any function whose frame size is larger
83 bool warn_frame_larger_than
86 HOST_WIDE_INT frame_larger_than_size
88 ; Nonzero means we should be saving declaration info into a .X file.
90 int flag_gen_aux_info = 0
92 ; Nonzero if we are compiling code for a shared library, zero for
97 ; These two are really VEC(char_p,heap) *.
100 void *flag_instrument_functions_exclude_functions
103 void *flag_instrument_functions_exclude_files
105 ; Generic structs (e.g. templates not explicitly specialized)
106 ; may not have a compilation unit associated with them, and so
107 ; may need to be treated differently from ordinary structs.
109 ; Structs only handled by reference (indirectly), will also usually
110 ; not need as much debugging information.
113 enum debug_struct_file debug_struct_ordinary[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
116 enum debug_struct_file debug_struct_generic[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
118 ; True if we should exit after parsing options.
120 bool exit_after_options
122 ; Type(s) of debugging information we are producing (if any). See
123 ; flag-types.h for the definitions of the different possible types of
124 ; debugging information.
126 enum debug_info_type write_symbols = NO_DEBUG
128 ; Level of debugging information we are producing. See flag-types.h
129 ; for the definitions of the different possible levels.
131 enum debug_info_levels debug_info_level = DINFO_LEVEL_NONE
133 ; Nonzero means use GNU-only extensions in the generated symbolic
134 ; debugging information. Currently, this only has an effect when
135 ; write_symbols is set to DBX_DEBUG, XCOFF_DEBUG, or DWARF_DEBUG.
137 bool use_gnu_debug_info_extensions
139 ; Original value of maximum field alignment in bytes, specified via
140 ; -fpack-struct=<value>.
142 unsigned int initial_max_fld_align = TARGET_DEFAULT_PACK_STRUCT
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
177 ; Name of top-level original source file (what was input to cpp).
178 ; This comes from the #-command at the beginning of the actual input.
179 ; If there isn't any there, then this is the cc1 input file name.
181 const char *main_input_filename
183 ; Pointer to base name in main_input_filename, with directories and a
184 ; single final extension removed, and the length of this base
188 const char *main_input_basename
191 int main_input_baselength
193 ; Which options have been printed by --help.
197 ; Which enums have been printed by --help. 0 = not printed, no
198 ; relevant options seen, 1 = relevant option seen, not yet printed, 2
201 char *help_enum_printed
203 ; The number of columns for --help output.
205 unsigned int help_columns
207 ; Whether this options structure has been through finish_options
209 bool flag_opts_finished
221 Driver Alias(coverage)
227 Common Separate Alias(d)
230 Common Joined Alias(d)
233 Common Separate Alias(dumpbase)
236 Common Separate Alias(dumpdir)
239 Driver Separate Alias(e)
242 Driver Joined Alias(e)
245 Common Warning Alias(Wextra)
248 Driver Separate Alias(Xassembler)
251 Driver JoinedOrMissing Alias(Xassembler)
254 Driver Separate Alias(Xlinker)
257 Driver JoinedOrMissing Alias(Xlinker)
260 Driver Separate Alias(u)
263 Driver Joined Alias(u)
266 Common Driver Var(help_flag)
267 Display this information
270 Common Driver Report Joined
271 --help=<class> Display descriptions of a specific class of options. <class> is one or more of optimizers, target, warnings, undocumented, params
274 Driver Separate Alias(x)
277 Driver Joined Alias(x)
280 Driver Separate Alias(L)
283 Driver Joined Alias(L)
285 -no-canonical-prefixes
286 Driver Alias(no-canonical-prefixes)
288 -no-standard-libraries
289 Driver Alias(nostdlib)
292 Driver Var(no_sysroot_suffix)
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(Wpedantic)
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 Alias(print-multiarch)
352 Driver Separate Alias(print-prog-name=)
355 Driver JoinedOrMissing Alias(print-prog-name=)
358 Driver Alias(print-search-dirs)
361 Driver Alias(print-sysroot)
363 -print-sysroot-headers-suffix
364 Driver Alias(print-sysroot-headers-suffix)
370 Driver Alias(save-temps)
376 Driver Separate Alias(specs=)
379 Driver Joined Alias(specs=)
385 Driver Alias(symbolic)
389 Alias for --help=target
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
401 Common Driver Alias(-help)
404 Common Driver Joined Alias(-help=)
407 Common Driver Alias(-target-help)
410 Common Driver Alias(-version)
414 --param <param>=<value> Set parameter <param> to value. See below for a complete list of parameters
417 Common Joined Alias(-param)
420 Driver Separate Alias(-sysroot=)
423 Driver JoinedOrMissing
429 Driver Joined Separate
435 Driver Joined Separate
441 Common JoinedOrMissing Optimization
442 -O<number> Set optimization level to <number>
446 Optimize for space rather than speed
450 Optimize for speed disregarding exact standards compliance
454 Optimize for debugging experience rather than speed or size
466 Driver Joined Separate
472 Driver Joined Separate
493 Common RejectNegative Warning Alias(Wextra)
494 This switch is deprecated; use -Wextra instead
497 Driver JoinedOrMissing
500 Driver JoinedOrMissing
503 Driver JoinedOrMissing
506 Common Var(warn_aggregate_return) Warning
507 Warn about returning structures, unions or arrays
510 Common Var(warn_array_bounds) Warning
511 Warn if an array is accessed out of bounds
514 Common Var(warn_attributes) Init(1) Warning
515 Warn about inappropriate attribute usage
518 Common Var(warn_cast_align) Warning
519 Warn about pointer casts which increase alignment
522 Common Var(warn_cpp) Init(1) Warning
523 Warn when a #warning directive is encountered
525 Wdeprecated-declarations
526 Common Var(warn_deprecated_decl) Init(1) Warning
527 Warn about uses of __attribute__((deprecated)) declarations
529 Wdisabled-optimization
530 Common Var(warn_disabled_optimization) Warning
531 Warn when an optimization pass is disabled
534 Common Var(warnings_are_errors)
535 Treat all warnings as errors
539 Treat specified warning as error
542 Common Var(extra_warnings) Warning
543 Print extra (possibly unwanted) warnings
546 Common Var(flag_fatal_errors)
547 Exit on the first error occurred
550 Common RejectNegative Joined UInteger
551 -Wframe-larger-than=<number> Warn if a function's stack frame requires more than <number> bytes
554 Common Var(warn_free_nonheap_object) Init(1) Warning
555 Warn when attempting to free a non-heap object
558 Common Var(warn_inline) Warning
559 Warn when an inlined function cannot be inlined
561 Winvalid-memory-model
562 Common Var(warn_invalid_memory_model) Init(1) Warning
563 Warn when an atomic memory model parameter is known to be outside the valid range.
566 Common RejectNegative Joined Warning Undocumented Alias(Wlarger-than=)
569 Common RejectNegative Joined UInteger Warning
570 -Wlarger-than=<number> Warn if an object is larger than <number> bytes
572 Wunsafe-loop-optimizations
573 Common Var(warn_unsafe_loop_optimizations) Warning
574 Warn if the loop cannot be optimized due to nontrivial assumptions.
577 Common Alias(Wsuggest-attribute=noreturn)
580 Common Var(warn_overflow) Init(1) Warning
581 Warn about overflow in arithmetic expressions
584 Common Var(warn_packed) Warning
585 Warn when the packed attribute has no effect on struct layout
588 Common Var(warn_padded) Warning
589 Warn when padding is required to align structure members
592 Common Var(pedantic) Warning
593 Issue warnings needed for strict compliance to the standard
596 Common Var(warn_shadow) Warning
597 Warn when one local variable shadows another
600 Common Var(warn_stack_protect) Warning
601 Warn when not issuing stack smashing protection for some reason
604 Common Joined RejectNegative UInteger Var(warn_stack_usage) Init(-1) Warning
605 Warn if stack usage might be larger than specified amount
609 Warn about code which might break strict aliasing rules
612 Common Joined RejectNegative UInteger Var(warn_strict_aliasing) Warning
613 Warn about code which might break strict aliasing rules
617 Warn about optimizations that assume that signed overflow is undefined
620 Common Joined RejectNegative UInteger Var(warn_strict_overflow) Warning
621 Warn about optimizations that assume that signed overflow is undefined
623 Wsuggest-attribute=const
624 Common Var(warn_suggest_attribute_const) Warning
625 Warn about functions which might be candidates for __attribute__((const))
627 Wsuggest-attribute=pure
628 Common Var(warn_suggest_attribute_pure) Warning
629 Warn about functions which might be candidates for __attribute__((pure))
631 Wsuggest-attribute=noreturn
632 Common Var(warn_suggest_attribute_noreturn) Warning
633 Warn about functions which might be candidates for __attribute__((noreturn))
636 Common Var(warn_system_headers) Warning
637 Do not suppress warnings from system headers
640 Common Var(warn_trampolines) Warning
641 Warn whenever a trampoline is generated
644 Common Var(warn_type_limits) Warning EnabledBy(Wextra)
645 Warn if a comparison is always true or always false due to the limited range of the data type
648 Common Var(warn_uninitialized) Warning EnabledBy(Wextra)
649 Warn about uninitialized automatic variables
652 Common Var(warn_maybe_uninitialized) Warning EnabledBy(Wuninitialized)
653 Warn about maybe uninitialized automatic variables
657 Does nothing. Preserved for backward compatibility.
660 Common Var(warn_unused) Init(0) Warning
661 Enable all -Wunused- warnings
663 Wunused-but-set-parameter
664 Common Var(warn_unused_but_set_parameter) Warning EnabledBy(Wunused && Wextra)
665 Warn when a function parameter is only set, otherwise unused
667 Wunused-but-set-variable
668 Common Var(warn_unused_but_set_variable) Warning EnabledBy(Wunused)
669 Warn when a variable is only set, otherwise unused
672 Common Var(warn_unused_function) Warning EnabledBy(Wunused)
673 Warn when a function is unused
676 Common Var(warn_unused_label) Warning EnabledBy(Wunused)
677 Warn when a label is unused
680 Common Var(warn_unused_parameter) Warning EnabledBy(Wunused && Wextra)
681 Warn when a function parameter is unused
684 Common Var(warn_unused_value) Warning EnabledBy(Wunused)
685 Warn when an expression value is unused
688 Common Var(warn_unused_variable) Warning EnabledBy(Wunused)
689 Warn when a variable is unused
692 Common Var(warn_coverage_mismatch) Init(1) Warning
693 Warn in case profiles in -fprofile-use do not match
695 Wvector-operation-performance
696 Common Var(warn_vector_operation_performance) Warning
697 Warn when a vector operation is compiled outside the SIMD
712 Common Separate Var(aux_info_file_name)
713 -aux-info <file> Emit declaration information into <file>
716 Common Joined Alias(aux-info)
719 Common Separate RejectDriver Var(aux_base_name)
722 Common Separate RejectDriver
732 -d<letters> Enable dumps from specific passes of the compiler
735 Common Separate Var(dump_base_name)
736 -dumpbase <file> Set the file basename to be used for dumps
739 Common Separate Var(dump_dir_name)
740 -dumpdir <dir> Set the directory name to be used for dumps
752 Driver Joined Separate
754 ; This option has historically been passed down to the linker by an
755 ; accident of a %{e*} spec, so ensure it continues to be passed down
756 ; as a single option. The supported option for this purpose is
757 ; -rdynamic. See PR 47390.
761 ; The version of the C++ ABI in use. The following values are allowed:
763 ; 0: The version of the ABI believed most conformant with the C++ ABI
764 ; specification. This ABI may change as bugs are discovered and fixed.
765 ; Therefore, 0 will not necessarily indicate the same ABI in different
768 ; 1: The version of the ABI first used in G++ 3.2.
770 ; 2: The version of the ABI first used in G++ 3.4 (and current default).
772 ; 3: The version of the ABI that fixes the missing underscore
773 ; in template non-type arguments of pointer type.
775 ; 4: The version of the ABI that introduces unambiguous mangling of
776 ; vector types. First selectable in G++ 4.5.
778 ; 5: The version of the ABI that ignores attribute const/noreturn
779 ; in function pointer mangling, and corrects mangling of decltype and
780 ; function parameters used in other parameters and the return type.
781 ; First selectable in G++ 4.6.
783 ; 6: The version of the ABI that doesn't promote scoped enums to int and
784 ; changes the mangling of template argument packs, const/static_cast,
785 ; prefix ++ and --, and a class scope function used as a template
787 ; First selectable in G++ 4.7.
789 ; 7: The version of the ABI that treats nullptr_t as a builtin type.
790 ; First selectable in G++ 4.8.
791 ; Additional positive integers will be assigned as new versions of
792 ; the ABI become the default version of the ABI.
794 Common Joined RejectNegative UInteger Var(flag_abi_version) Init(2)
797 Common Report Var(align_functions,0) Optimization UInteger
798 Align the start of functions
801 Common RejectNegative Joined UInteger Var(align_functions)
804 Common Report Var(align_jumps,0) Optimization UInteger
805 Align labels which are only reached by jumping
808 Common RejectNegative Joined UInteger Var(align_jumps)
811 Common Report Var(align_labels,0) Optimization UInteger
815 Common RejectNegative Joined UInteger Var(align_labels)
818 Common Report Var(align_loops,0) Optimization UInteger
819 Align the start of loops
822 Common RejectNegative Joined UInteger Var(align_loops)
826 Does nothing. Preserved for backward compatibility.
830 Does nothing. Preserved for backward compatibility.
832 fargument-noalias-global
834 Does nothing. Preserved for backward compatibility.
836 fargument-noalias-anything
838 Does nothing. Preserved for backward compatibility.
841 Common Report Var(flag_asan)
842 Enable AddressSanitizer, a memory error detector
845 Common Report Var(flag_tsan)
846 Enable ThreadSanitizer, a data race detector
848 fasynchronous-unwind-tables
849 Common Report Var(flag_asynchronous_unwind_tables) Optimization
850 Generate unwind tables that are exact at each instruction boundary
853 Common Report Var(flag_auto_inc_dec) Init(1)
854 Generate auto-inc/dec instructions
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.
861 Common Report Var(flag_bounds_check)
862 Generate code to check bounds before indexing arrays
865 Common Report Var(flag_branch_on_count_reg) Init(1) Optimization
866 Replace add, compare, branch with branch on count register
868 fbranch-probabilities
869 Common Report Var(flag_branch_probabilities) Optimization
870 Use profiling information for branch probabilities
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
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
881 Common Report Var(flag_btr_bb_exclusive) Optimization
882 Restrict target load migration not to re-use registers in any basic block
885 Common Joined RejectNegative Var(common_deferred_options) Defer
886 -fcall-saved-<register> Mark <register> as being preserved across functions
889 Common Joined RejectNegative Var(common_deferred_options) Defer
890 -fcall-used-<register> Mark <register> as being corrupted by function calls
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.
896 Common Report Var(flag_caller_saves) Optimization
897 Save registers around function calls
900 Common Report Var(flag_check_data_deps)
901 Compare the results of several data dependence analyzers.
903 fcombine-stack-adjustments
904 Common Report Var(flag_combine_stack_adjustments) Optimization
905 Looks for opportunities to reduce stack adjustments and stack references.
908 Common Report Var(flag_no_common,0) Optimization
909 Do not put uninitialized globals in the common section
913 ; Converted by the driver to -fcompare-debug= options.
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
919 fcompare-debug-second
920 Common Driver RejectNegative Var(flag_compare_debug)
921 Run only the second compilation of -fcompare-debug
924 Common Report Var(flag_compare_elim_after_reload) Optimization
925 Perform comparison elimination after register allocation has finished
928 Common Var(flag_conserve_stack) Optimization
929 Do not perform optimizations increasing noticeably stack usage
932 Common Report Var(flag_cprop_registers) Optimization
933 Perform a register copy-propagation optimization pass
936 Common Report Var(flag_crossjumping) Optimization
937 Perform cross-jumping optimization
940 Common Report Var(flag_cse_follow_jumps) Optimization
941 When running CSE, follow jumps to their targets
945 Does nothing. Preserved for backward compatibility.
948 Common Report Var(flag_cx_limited_range) Optimization SetByCombined
949 Omit range reduction step when performing complex division
952 Common Report Var(flag_cx_fortran_rules) Optimization
953 Complex multiplication and division follow Fortran rules
956 Common Report Var(flag_data_sections) Optimization
957 Place data items into their own section
960 Common Report Var(common_deferred_options) Defer
961 List all available debugging counters with their limits and counts.
964 Common RejectNegative Joined Var(common_deferred_options) Defer
965 -fdbg-cnt=<counter>:<limit>[,<counter>:<limit>,...] Set the debug counter limit.
968 Common Joined RejectNegative Var(common_deferred_options) Defer
969 Map one directory name to another in debug information
972 Common Report Var(flag_debug_types_section) Init(0)
973 Output .debug_types section when using DWARF v4 debuginfo.
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.
978 Common Report Var(flag_defer_pop) Optimization
979 Defer popping functions args from stack until later
982 Common Report Var(flag_delayed_branch) Optimization
983 Attempt to fill delay slots of branch instructions
985 fdelete-dead-exceptions
986 Common Report Var(flag_delete_dead_exceptions) Init(0)
987 Delete dead instructions that may throw exceptions
989 fdelete-null-pointer-checks
990 Common Report Var(flag_delete_null_pointer_checks) Init(1) Optimization
991 Delete useless null pointer checks
994 Common Report Var(flag_devirtualize) Optimization
995 Try to convert virtual calls to direct ones.
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
1001 ; Required for these enum values.
1006 Name(diagnostic_prefixing_rule) Type(int)
1009 Enum(diagnostic_prefixing_rule) String(once) Value(DIAGNOSTICS_SHOW_PREFIX_ONCE)
1012 Enum(diagnostic_prefixing_rule) String(every-line) Value(DIAGNOSTICS_SHOW_PREFIX_EVERY_LINE)
1014 fdiagnostics-show-caret
1015 Common Var(flag_diagnostics_show_caret) Init(1)
1016 Show the source line with a caret indicating the column
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
1023 Common Joined RejectNegative Var(common_deferred_options) Defer
1024 -fdisable-[tree|rtl|ipa]-<pass>=range1+range2 disables an optimization pass
1027 Common Joined RejectNegative Var(common_deferred_options) Defer
1028 -fenable-[tree|rtl|ipa]-<pass>=range1+range2 enables an optimization pass
1031 Common Joined RejectNegative Var(common_deferred_options) Defer
1032 -fdump-<type> Dump various compiler internals to a file
1035 Driver RejectNegative
1038 Common RejectNegative Joined Var(flag_dump_final_insns)
1039 -fdump-final-insns=filename Dump to filename the insns at the end of translation
1042 Common RejectNegative Joined Var(flag_dump_go_spec)
1043 -fdump-go-spec=filename Write all declarations to file as Go code
1046 Common Report Var(flag_dump_noaddr)
1047 Suppress output of addresses in debugging dumps
1050 Common Var(flag_dump_passes) Init(0)
1051 Dump optimization passes
1054 Common Report Var(flag_dump_unnumbered)
1055 Suppress output of instruction numbers, line number notes and addresses in debugging dumps
1057 fdump-unnumbered-links
1058 Common Report Var(flag_dump_unnumbered_links)
1059 Suppress output of previous and next insn numbers in debugging dumps
1062 Common Report Var(flag_dwarf2_cfi_asm) Init(HAVE_GAS_CFI_DIRECTIVE)
1063 Enable CFI tables via GAS assembler directives.
1066 Common Report Var(flag_early_inlining) Init(1) Optimization
1067 Perform early inlining
1069 feliminate-dwarf2-dups
1070 Common Report Var(flag_eliminate_dwarf2_dups)
1071 Perform DWARF2 duplicate elimination
1074 Common Report Var(flag_ipa_sra) Init(0) Optimization
1075 Perform interprocedural reduction of aggregates
1077 feliminate-unused-debug-symbols
1078 Common Report Var(flag_debug_only_used_symbols)
1079 Perform unused type elimination in debug info
1081 feliminate-unused-debug-types
1082 Common Report Var(flag_eliminate_unused_debug_types) Init(1)
1083 Perform unused type elimination in debug info
1085 femit-class-debug-always
1086 Common Report Var(flag_emit_class_debug_always) Init(0)
1087 Do not suppress C++ class debug information.
1090 Common Report Var(flag_exceptions) Optimization
1091 Enable exception handling
1093 fexpensive-optimizations
1094 Common Report Var(flag_expensive_optimizations) Optimization
1095 Perform a number of minor, expensive optimizations
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
1102 Name(excess_precision) Type(enum excess_precision) UnknownError(unknown excess precision style %qs)
1105 Enum(excess_precision) String(fast) Value(EXCESS_PRECISION_FAST)
1108 Enum(excess_precision) String(standard) Value(EXCESS_PRECISION_STANDARD)
1114 Common Var(flag_fat_lto_objects) Init(1)
1115 Output lto objects containing both the intermediate language and binary output.
1118 Common Report Var(flag_finite_math_only) Optimization SetByCombined
1119 Assume no NaNs or infinities are generated
1122 Common Joined RejectNegative Var(common_deferred_options) Defer
1123 -ffixed-<register> Mark <register> as being unavailable to the compiler
1126 Common Report Var(flag_float_store) Optimization
1127 Don't allocate floats and doubles in extended-precision registers
1131 Does nothing. Preserved for backward compatibility.
1134 Common Report Var(flag_forward_propagate) Optimization
1135 Perform a forward propagation pass on RTL
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.
1142 Name(fp_contract_mode) Type(enum fp_contract_mode) UnknownError(unknown floating point contraction style %qs)
1145 Enum(fp_contract_mode) String(off) Value(FP_CONTRACT_OFF)
1147 ; Not implemented, fall back to conservative FP_CONTRACT_OFF.
1149 Enum(fp_contract_mode) String(on) Value(FP_CONTRACT_OFF)
1152 Enum(fp_contract_mode) String(fast) Value(FP_CONTRACT_FAST)
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.
1158 Common Report Var(flag_no_function_cse,0)
1159 Allow function addresses to be held in registers
1162 Common Report Var(flag_function_sections)
1163 Place each function into its own section
1166 Common Report Var(flag_gcse) Optimization
1167 Perform global common subexpression elimination
1170 Common Report Var(flag_gcse_lm) Init(1) Optimization
1171 Perform enhanced load motion during global common subexpression elimination
1174 Common Report Var(flag_gcse_sm) Init(0) Optimization
1175 Perform store motion after global common subexpression elimination
1178 Common Report Var(flag_gcse_las) Init(0) Optimization
1179 Perform redundant load after store elimination in global common subexpression
1183 Common Report Var(flag_gcse_after_reload) Optimization
1184 Perform global common subexpression elimination after register allocation
1187 ; This option is not documented yet as its semantics will change.
1189 Common Report Var(flag_graphite)
1190 Enable in and out of Graphite representation
1193 Common Report Var(flag_graphite_identity) Optimization
1194 Enable Graphite Identity transformation
1196 fhoist-adjacent-loads
1197 Common Report Var(flag_hoist_adjacent_loads) Optimization
1198 Enable hoisting adjacent loads to encourage generating conditional move
1201 floop-parallelize-all
1202 Common Report Var(flag_loop_parallelize_all) Optimization
1203 Mark all loops as parallel
1206 Common Report Var(flag_loop_strip_mine) Optimization
1207 Enable Loop Strip Mining transformation
1210 Common Report Var(flag_loop_interchange) Optimization
1211 Enable Loop Interchange transformation
1214 Common Report Var(flag_loop_block) Optimization
1215 Enable Loop Blocking transformation
1218 Common Report Var(flag_tm)
1219 Enable support for GNU transactional memory
1223 Does nothing. Preserved for backward compatibility.
1226 Common Report Var(flag_loop_optimize_isl) Optimization
1227 Enable the ISL based loop nest optimizer
1229 fstrict-volatile-bitfields
1230 Common Report Var(flag_strict_volatile_bitfields) Init(-1)
1231 Force bitfield accesses to match their type width
1233 fguess-branch-probability
1234 Common Report Var(flag_guess_branch_prob) Optimization
1235 Enable guessing of branch probabilities
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.
1242 Common Report Var(flag_no_ident,0)
1243 Process #ident directives
1246 Common Report Var(flag_if_conversion) Optimization
1247 Perform conversion of conditional jumps to branchless equivalents
1250 Common Report Var(flag_if_conversion2) Optimization
1251 Perform conversion of conditional jumps to conditional execution
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.
1258 Name(stack_reuse_level) Type(enum stack_reuse_level) UnknownError(unknown Stack Reuse Level %qs)
1261 Enum(stack_reuse_level) String(all) Value(SR_ALL)
1264 Enum(stack_reuse_level) String(named_vars) Value(SR_NAMED_VARS)
1267 Enum(stack_reuse_level) String(none) Value(SR_NONE)
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
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
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
1286 Common Report Var(flag_indirect_inlining)
1287 Perform indirect inlining
1289 ; General flag to enable inlining. Specifying -fno-inline will disable
1290 ; all inlining apart from always-inline functions.
1292 Common Report Var(flag_no_inline,0) Init(0) Optimization
1293 Enable inlining of function declared \"inline\", disabling disables all inlining
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
1300 Common Report Var(flag_inline_functions) Optimization
1301 Integrate functions not declared \"inline\" into their callers when profitable
1303 finline-functions-called-once
1304 Common Report Var(flag_inline_functions_called_once) Optimization
1305 Integrate functions only required by their single caller
1308 Common RejectNegative Joined Alias(finline-limit=)
1311 Common RejectNegative Joined UInteger
1312 -finline-limit=<number> Limit the size of inlined functions to <number>
1315 Common Report Var(flag_inline_atomics) Init(1) Optimization
1316 Inline __atomic operations when a lock free instruction sequence is available.
1318 finstrument-functions
1319 Common Report Var(flag_instrument_function_entry_exit)
1320 Instrument function entry and exit with profiling calls
1322 finstrument-functions-exclude-function-list=
1323 Common RejectNegative Joined
1324 -finstrument-functions-exclude-function-list=name,... Do not instrument listed functions
1326 finstrument-functions-exclude-file-list=
1327 Common RejectNegative Joined
1328 -finstrument-functions-exclude-file-list=filename,... Do not instrument functions listed in files
1331 Common Report Var(flag_ipa_cp) Optimization
1332 Perform Interprocedural constant propagation
1335 Common Report Var(flag_ipa_cp_clone) Optimization
1336 Perform cloning to make Interprocedural constant propagation stronger
1339 Common Report Var(flag_ipa_profile) Init(0) Optimization
1340 Perform interprocedural profile propagation
1343 Common Report Var(flag_ipa_pta) Init(0) Optimization
1344 Perform interprocedural points-to analysis
1347 Common Report Var(flag_ipa_pure_const) Init(0) Optimization
1348 Discover pure and const functions
1351 Common Report Var(flag_ipa_reference) Init(0) Optimization
1352 Discover readonly and non addressable static variables
1356 Does nothing. Preserved for backward compatibility.
1360 Does nothing. Preserved for backward compatibility.
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
1367 Name(ira_algorithm) Type(enum ira_algorithm) UnknownError(unknown IRA algorithm %qs)
1370 Enum(ira_algorithm) String(CB) Value(IRA_ALGORITHM_CB)
1373 Enum(ira_algorithm) String(priority) Value(IRA_ALGORITHM_PRIORITY)
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
1380 Name(ira_region) Type(enum ira_region) UnknownError(unknown IRA region %qs)
1383 Enum(ira_region) String(one) Value(IRA_REGION_ONE)
1386 Enum(ira_region) String(all) Value(IRA_REGION_ALL)
1389 Enum(ira_region) String(mixed) Value(IRA_REGION_MIXED)
1392 Common Report Var(flag_ira_hoist_pressure) Init(1) Optimization
1393 Use IRA based register pressure calculation
1394 in RTL hoist optimizations.
1397 Common Report Var(flag_ira_loop_pressure)
1398 Use IRA based register pressure calculation
1399 in RTL loop optimizations.
1401 fira-share-save-slots
1402 Common Report Var(flag_ira_share_save_slots) Init(1)
1403 Share slots for saving different hard registers.
1405 fira-share-spill-slots
1406 Common Report Var(flag_ira_share_spill_slots) Init(1)
1407 Share stack slots for spilled pseudo-registers.
1410 Common RejectNegative Joined UInteger Var(flag_ira_verbose) Init(5)
1411 -fira-verbose=<number> Control IRA's level of diagnostic messages.
1414 Common Report Var(flag_ivopts) Init(1) Optimization
1415 Optimize induction variables on trees
1418 Common Var(flag_jump_tables) Init(1) Optimization
1419 Use jump tables for sufficiently large switch statements
1421 fkeep-inline-functions
1422 Common Report Var(flag_keep_inline_functions)
1423 Generate code for functions even if they are fully inlined
1426 Common Report Var(flag_keep_static_consts) Init(1)
1427 Emit static const variables even if they are not used
1430 Common Report Var(flag_leading_underscore) Init(-1)
1431 Give external symbols a leading underscore
1435 Does nothing. Preserved for backward compatibility.
1439 Enable link-time optimization.
1442 Common RejectNegative Joined Var(flag_lto)
1443 Link-time optimization with number of parallel jobs or jobserver.
1446 Common Var(flag_lto_partition_1to1)
1447 Partition symbols and vars at linktime based on object files they originate from
1449 flto-partition=balanced
1450 Common Var(flag_lto_partition_balanced)
1451 Partition functions and vars at linktime into approximately same sized buckets
1454 Common Var(flag_lto_partition_max)
1455 Put every symbol into separate partition
1458 Common Var(flag_lto_partition_none)
1459 Disable partioning and streaming
1461 ; The initial value of -1 comes from Z_DEFAULT_COMPRESSION in zlib.h.
1462 flto-compression-level=
1463 Common Joined RejectNegative UInteger Var(flag_lto_compression_level) Init(-1)
1464 -flto-compression-level=<number> Use zlib compression level <number> for IL
1467 Common Report Var(flag_lto_report) Init(0)
1468 Report various link-time optimization statistics
1471 Common Report Var(flag_errno_math) Init(1) Optimization SetByCombined
1472 Set errno after built-in math functions
1475 Common Joined RejectNegative UInteger Var(flag_max_errors)
1476 -fmax-errors=<number> Maximum number of errors to report
1479 Common Report Var(mem_report)
1480 Report on permanent memory allocation
1483 Common Report Var(mem_report_wpa)
1484 Report on permanent memory allocation in WPA only
1486 ; This will attempt to merge constant section constants, if 1 only
1487 ; string constants and constants from constant pool, if 2 also constant
1489 fmerge-all-constants
1490 Common Report Var(flag_merge_constants,2) Init(1) Optimization
1491 Attempt to merge identical constants and constant variables
1494 Common Report Var(flag_merge_constants,1) Optimization
1495 Attempt to merge identical constants across compilation units
1497 fmerge-debug-strings
1498 Common Report Var(flag_merge_debug_strings) Init(1)
1499 Attempt to merge identical debug strings across compilation units
1502 Common RejectNegative Joined UInteger
1503 -fmessage-length=<number> Limit diagnostics to <number> characters per line. 0 suppresses line-wrapping
1506 Common Report Var(flag_modulo_sched) Optimization
1507 Perform SMS based modulo scheduling before the first scheduling pass
1509 fmodulo-sched-allow-regmoves
1510 Common Report Var(flag_modulo_sched_allow_regmoves)
1511 Perform SMS based modulo scheduling with register moves allowed
1513 fmove-loop-invariants
1514 Common Report Var(flag_move_loop_invariants) Init(1) Optimization
1515 Move loop invariant computations out of loops
1518 Common Var(flag_dce) Init(1) Optimization
1519 Use the RTL dead code elimination pass
1522 Common Var(flag_dse) Init(1) Optimization
1523 Use the RTL dead store elimination pass
1525 freschedule-modulo-scheduled-loops
1526 Common Report Var(flag_resched_modulo_sched) Optimization
1527 Enable/Disable the traditional scheduling in loops that already passed modulo scheduling
1529 fnon-call-exceptions
1530 Common Report Var(flag_non_call_exceptions) Optimization
1531 Support synchronous non-call exceptions
1534 Common Report Var(flag_omit_frame_pointer) Optimization
1535 When possible do not generate stack frames
1538 Common Report Var(flag_opt_info) Optimization
1539 Enable all optimization info dumps on stderr
1542 Common Joined RejectNegative Var(common_deferred_options) Defer
1543 -fopt-info[-<type>=filename] Dump compiler optimization details
1545 foptimize-register-move
1546 Common Report Var(flag_regmove) Optimization
1547 Do the full register move optimization pass
1549 foptimize-sibling-calls
1550 Common Report Var(flag_optimize_sibling_calls) Optimization
1551 Optimize sibling and tail recursive calls
1554 Common Report Var(flag_partial_inlining)
1555 Perform partial inlining
1558 Common Report Var(pre_ipa_mem_report)
1559 Report on memory allocation before interprocedural optimization
1561 fpost-ipa-mem-report
1562 Common Report Var(post_ipa_mem_report)
1563 Report on memory allocation before interprocedural optimization
1566 Common Report Var(flag_pack_struct) Optimization
1567 Pack structure members together without holes
1570 Common RejectNegative Joined UInteger Optimization
1571 -fpack-struct=<number> Set initial maximum structure member alignment
1574 Common Report Var(flag_pcc_struct_return,1) Init(DEFAULT_PCC_STRUCT_RETURN)
1575 Return small aggregates in memory, not registers
1578 Common Report Var(flag_peel_loops) Optimization
1579 Perform loop peeling
1582 Common Report Var(flag_no_peephole,0) Optimization
1583 Enable machine specific peephole optimizations
1586 Common Report Var(flag_peephole2) Optimization
1587 Enable an RTL peephole pass before sched2
1590 Common Report Var(flag_pic,2) Negative(fPIE)
1591 Generate position-independent code if possible (large mode)
1594 Common Report Var(flag_pie,2) Negative(fpic)
1595 Generate position-independent code for executables if possible (large mode)
1598 Common Report Var(flag_pic,1) Negative(fpie)
1599 Generate position-independent code if possible (small mode)
1602 Common Report Var(flag_pie,1) Negative(fPIC)
1603 Generate position-independent code for executables if possible (small mode)
1606 Common Joined RejectNegative Var(common_deferred_options) Defer
1607 Specify a plugin to load
1610 Common Joined RejectNegative Var(common_deferred_options) Defer
1611 -fplugin-arg-<name>-<key>[=<value>] Specify argument <key>=<value> for plugin <name>
1613 fpredictive-commoning
1614 Common Report Var(flag_predictive_commoning) Optimization
1615 Run predictive commoning optimization.
1617 fprefetch-loop-arrays
1618 Common Report Var(flag_prefetch_loop_arrays) Init(-1) Optimization
1619 Generate prefetch instructions, if available, for arrays in loops
1622 Common Report Var(profile_flag)
1623 Enable basic program profiling code
1626 Common Report Var(profile_arc_flag)
1627 Insert arc-based program profiling code
1630 Common Joined RejectNegative Var(profile_data_prefix)
1631 Set the top-level directory for storing the profile data.
1632 The default is 'pwd'.
1635 Common Report Var(flag_profile_correction)
1636 Enable correction of flow inconsistent profile data input
1640 Enable common options for generating profile info for profile feedback directed optimizations
1643 Common Joined RejectNegative
1644 Enable common options for generating profile info for profile feedback directed optimizations, and set -fprofile-dir=
1647 Common Var(flag_profile_use)
1648 Enable common options for performing profile feedback directed optimizations
1651 Common Joined RejectNegative
1652 Enable common options for performing profile feedback directed optimizations, and set -fprofile-dir=
1655 Common Report Var(flag_profile_values)
1656 Insert code to profile values of expressions
1659 Common Report Var(profile_report)
1660 Report on consistency of profile
1663 Common Var(common_deferred_options) Defer
1666 Common Joined RejectNegative Var(common_deferred_options) Defer
1667 -frandom-seed=<string> Make compile reproducible using <string>
1669 ; This switch causes the command line that was used to create an
1670 ; object file to be recorded into the object file. The exact format
1671 ; of this recording is target and binary file format dependent.
1672 ; It is related to the -fverbose-asm switch, but that switch only
1673 ; records information in the assembler output file as comments, so
1674 ; they never reach the object file.
1675 frecord-gcc-switches
1676 Common Report Var(flag_record_gcc_switches)
1677 Record gcc command line switches in the object file.
1680 Common Report Var(flag_pcc_struct_return,0) Optimization
1681 Return small aggregates in registers
1684 Common Report Var(flag_regmove) Optimization
1685 Enables a register move optimization
1688 Common Report Var(flag_rename_registers) Init(2) Optimization
1689 Perform a register renaming optimization pass
1692 Common Report Var(flag_reorder_blocks) Optimization
1693 Reorder basic blocks to improve code placement
1695 freorder-blocks-and-partition
1696 Common Report Var(flag_reorder_blocks_and_partition) Optimization
1697 Reorder basic blocks and partition into hot and cold sections
1700 Common Report Var(flag_reorder_functions) Optimization
1701 Reorder functions to improve code placement
1703 frerun-cse-after-loop
1704 Common Report Var(flag_rerun_cse_after_loop) Optimization
1705 Add a common subexpression elimination pass after loop optimizations
1709 Does nothing. Preserved for backward compatibility.
1712 Common Report Var(flag_rounding_math) Optimization SetByCombined
1713 Disable optimizations that assume default FP rounding behavior
1716 Common Report Var(flag_schedule_interblock) Init(1) Optimization
1717 Enable scheduling across basic blocks
1720 Common Report Var(flag_sched_pressure) Init(0) Optimization
1721 Enable register pressure sensitive insn scheduling
1724 Common Report Var(flag_schedule_speculative) Init(1) Optimization
1725 Allow speculative motion of non-loads
1728 Common Report Var(flag_schedule_speculative_load) Optimization
1729 Allow speculative motion of some loads
1731 fsched-spec-load-dangerous
1732 Common Report Var(flag_schedule_speculative_load_dangerous) Optimization
1733 Allow speculative motion of more loads
1736 Common RejectNegative Joined UInteger Var(sched_verbose_param)
1737 -fsched-verbose=<number> Set the verbosity level of the scheduler
1739 fsched2-use-superblocks
1740 Common Report Var(flag_sched2_use_superblocks) Optimization
1741 If scheduling post reload, do superblock scheduling
1745 Does nothing. Preserved for backward compatibility.
1748 Common Report Var(flag_schedule_insns) Optimization
1749 Reschedule instructions before register allocation
1752 Common Report Var(flag_schedule_insns_after_reload) Optimization
1753 Reschedule instructions after register allocation
1755 ; This flag should be on when a target implements non-trivial
1756 ; scheduling hooks, maybe saving some information for its own sake.
1757 ; On IA64, for example, this is used for correct bundling.
1758 fselective-scheduling
1759 Common Report Var(flag_selective_scheduling) Optimization
1760 Schedule instructions using selective scheduling algorithm
1762 fselective-scheduling2
1763 Common Report Var(flag_selective_scheduling2) Optimization
1764 Run selective scheduling after reload
1766 fsel-sched-pipelining
1767 Common Report Var(flag_sel_sched_pipelining) Init(0) Optimization
1768 Perform software pipelining of inner loops during selective scheduling
1770 fsel-sched-pipelining-outer-loops
1771 Common Report Var(flag_sel_sched_pipelining_outer_loops) Init(0) Optimization
1772 Perform software pipelining of outer loops during selective scheduling
1774 fsel-sched-reschedule-pipelined
1775 Common Report Var(flag_sel_sched_reschedule_pipelined) Init(0) Optimization
1776 Reschedule pipelined regions without pipelining
1778 ; sched_stalled_insns means that insns can be moved prematurely from the queue
1779 ; of stalled insns into the ready list.
1780 fsched-stalled-insns
1781 Common Report Var(flag_sched_stalled_insns) Optimization UInteger
1782 Allow premature scheduling of queued insns
1784 fsched-stalled-insns=
1785 Common RejectNegative Joined UInteger
1786 -fsched-stalled-insns=<number> Set number of queued insns that can be prematurely scheduled
1788 ; sched_stalled_insns_dep controls how many recently scheduled cycles will
1789 ; be examined for a dependency on a stalled insn that is candidate for
1790 ; premature removal from the queue of stalled insns into the ready list (has
1791 ; an effect only if the flag 'sched_stalled_insns' is set).
1792 fsched-stalled-insns-dep
1793 Common Report Var(flag_sched_stalled_insns_dep,1) Init(1) Optimization UInteger
1794 Set dependence distance checking in premature scheduling of queued insns
1796 fsched-stalled-insns-dep=
1797 Common RejectNegative Joined UInteger
1798 -fsched-stalled-insns-dep=<number> Set dependence distance checking in premature scheduling of queued insns
1800 fsched-group-heuristic
1801 Common Report Var(flag_sched_group_heuristic) Init(1) Optimization
1802 Enable the group heuristic in the scheduler
1804 fsched-critical-path-heuristic
1805 Common Report Var(flag_sched_critical_path_heuristic) Init(1) Optimization
1806 Enable the critical path heuristic in the scheduler
1808 fsched-spec-insn-heuristic
1809 Common Report Var(flag_sched_spec_insn_heuristic) Init(1) Optimization
1810 Enable the speculative instruction heuristic in the scheduler
1812 fsched-rank-heuristic
1813 Common Report Var(flag_sched_rank_heuristic) Init(1) Optimization
1814 Enable the rank heuristic in the scheduler
1816 fsched-last-insn-heuristic
1817 Common Report Var(flag_sched_last_insn_heuristic) Init(1) Optimization
1818 Enable the last instruction heuristic in the scheduler
1820 fsched-dep-count-heuristic
1821 Common Report Var(flag_sched_dep_count_heuristic) Init(1) Optimization
1822 Enable the dependent count heuristic in the scheduler
1825 Common Report Var(flag_section_anchors) Optimization
1826 Access data in the same section from shared anchor points
1830 Does nothing. Preserved for backward compatibility.
1834 Does nothing. Preserved for backward compatibility.
1837 Common Report Var(flag_ree) Init(0)
1838 Turn on Redundant Extensions Elimination pass.
1841 Common Report Var(flag_show_column) Init(1)
1842 Show column numbers in diagnostics, when available. Default on
1845 Common Report Var(flag_shrink_wrap) Optimization
1846 Emit function prologues only before parts of the function that need it,
1847 rather than at the top of the function.
1850 Common Report Var(flag_signaling_nans) Optimization SetByCombined
1851 Disable optimizations observable by IEEE signaling NaNs
1854 Common Report Var(flag_signed_zeros) Init(1) Optimization SetByCombined
1855 Disable floating point optimizations that ignore the IEEE signedness of zero
1857 fsingle-precision-constant
1858 Common Report Var(flag_single_precision_constant) Optimization
1859 Convert floating point constants to single precision constants
1861 fsplit-ivs-in-unroller
1862 Common Report Var(flag_split_ivs_in_unroller) Init(1) Optimization
1863 Split lifetimes of induction variables when loops are unrolled
1866 Common Report Var(flag_split_stack) Init(-1)
1867 Generate discontiguous stack frames
1870 Common Report Var(flag_split_wide_types) Optimization
1871 Split wide types into independent registers
1873 fvariable-expansion-in-unroller
1874 Common Report Var(flag_variable_expansion_in_unroller) Optimization
1875 Apply variable expansion when loops are unrolled
1878 Common Report RejectNegative Joined
1879 -fstack-check=[no|generic|specific] Insert stack checking code into the program
1882 Common Alias(fstack-check=, specific, no)
1883 Insert stack checking code into the program. Same as -fstack-check=specific
1886 Common Var(common_deferred_options) Defer
1888 fstack-limit-register=
1889 Common RejectNegative Joined Var(common_deferred_options) Defer
1890 -fstack-limit-register=<register> Trap if the stack goes past <register>
1892 fstack-limit-symbol=
1893 Common RejectNegative Joined Var(common_deferred_options) Defer
1894 -fstack-limit-symbol=<name> Trap if the stack goes past symbol <name>
1897 Common Report Var(flag_stack_protect, 1)
1898 Use propolice as a stack protection method
1900 fstack-protector-all
1901 Common Report RejectNegative Var(flag_stack_protect, 2)
1902 Use a stack protection method for every function
1905 Common RejectNegative Var(flag_stack_usage)
1906 Output stack usage information on a per-function basis
1910 Does nothing. Preserved for backward compatibility.
1912 ; Nonzero if we should do (language-dependent) alias analysis.
1913 ; Typically, this analysis will assume that expressions of certain
1914 ; types do not alias expressions of certain other types. Only used
1915 ; if alias analysis (in general) is enabled.
1917 Common Report Var(flag_strict_aliasing) Optimization
1918 Assume strict aliasing rules apply
1921 Common Report Var(flag_strict_overflow)
1922 Treat signed overflow as undefined
1925 Common Report Var(flag_sync_libcalls) Init(1)
1926 Implement __atomic operations via libcalls to legacy __sync functions
1929 Common Report Var(flag_syntax_only)
1930 Check for syntax errors, then stop
1933 Common Report Var(flag_test_coverage)
1934 Create data files needed by \"gcov\"
1937 Common Report Var(flag_thread_jumps) Optimization
1938 Perform jump threading optimizations
1941 Common Report Var(time_report)
1942 Report the time taken by each compiler pass
1945 Common Joined RejectNegative Enum(tls_model) Var(flag_tls_default) Init(TLS_MODEL_GLOBAL_DYNAMIC)
1946 -ftls-model=[global-dynamic|local-dynamic|initial-exec|local-exec] Set the default thread-local storage code generation model
1949 Name(tls_model) Type(enum tls_model) UnknownError(unknown TLS model %qs)
1952 Enum(tls_model) String(global-dynamic) Value(TLS_MODEL_GLOBAL_DYNAMIC)
1955 Enum(tls_model) String(local-dynamic) Value(TLS_MODEL_LOCAL_DYNAMIC)
1958 Enum(tls_model) String(initial-exec) Value(TLS_MODEL_INITIAL_EXEC)
1961 Enum(tls_model) String(local-exec) Value(TLS_MODEL_LOCAL_EXEC)
1964 Common Report Var(flag_toplevel_reorder) Init(2) Optimization
1965 Reorder top level functions, variables, and asms
1968 Common Report Var(flag_tracer)
1969 Perform superblock formation via tail duplication
1971 ; Zero means that floating-point math operations cannot generate a
1972 ; (user-visible) trap. This is the case, for example, in nonstop
1973 ; IEEE 754 arithmetic.
1975 Common Report Var(flag_trapping_math) Init(1) Optimization SetByCombined
1976 Assume floating-point operations can trap
1979 Common Report Var(flag_trapv) Optimization
1980 Trap for signed overflow in addition, subtraction and multiplication
1983 Common Report Var(flag_tree_ccp) Optimization
1984 Enable SSA-CCP optimization on trees
1987 Common Report Var(flag_tree_bit_ccp) Optimization
1988 Enable SSA-BIT-CCP optimization on trees
1992 Does nothing. Preserved for backward compatibility.
1995 Common Report Var(flag_tree_ch) Optimization
1996 Enable loop header copying on trees
1998 ftree-coalesce-inlined-vars
1999 Common Report Var(flag_ssa_coalesce_vars,1) Init(2) RejectNegative Optimization
2000 Enable coalescing of copy-related user variables that are inlined
2003 Common Report Var(flag_ssa_coalesce_vars,2) Optimization
2004 Enable coalescing of all copy-related user variables
2007 Common Report Var(flag_tree_copyrename) Optimization
2008 Replace SSA temporaries with better names in copies
2011 Common Report Var(flag_tree_copy_prop) Optimization
2012 Enable copy propagation on trees
2014 ftree-store-copy-prop
2016 Does nothing. Preserved for backward compatibility.
2019 Common Report Var(flag_tree_cselim) Init(2) Optimization
2020 Transform condition stores into unconditional ones
2022 ftree-switch-conversion
2023 Common Report Var(flag_tree_switch_conversion) Optimization
2024 Perform conversions of switch initializations.
2027 Common Report Var(flag_tree_dce) Optimization
2028 Enable SSA dead code elimination optimization on trees
2030 ftree-dominator-opts
2031 Common Report Var(flag_tree_dom) Optimization
2032 Enable dominator optimizations
2035 Common Report Var(flag_tree_tail_merge) Optimization
2036 Enable tail merging on trees
2039 Common Report Var(flag_tree_dse) Optimization
2040 Enable dead store elimination
2043 Common Report Var(flag_tree_forwprop) Init(1) Optimization
2044 Enable forward propagation on trees
2047 Common Report Var(flag_tree_fre) Optimization
2048 Enable Full Redundancy Elimination (FRE) on trees
2051 Common Report Var(flag_optimize_strlen) Optimization
2052 Enable string length optimizations on trees
2054 ftree-loop-distribution
2055 Common Report Var(flag_tree_loop_distribution) Optimization
2056 Enable loop distribution on trees
2058 ftree-loop-distribute-patterns
2059 Common Report Var(flag_tree_loop_distribute_patterns) Optimization
2060 Enable loop distribution for patterns transformed into a library call
2063 Common Report Var(flag_tree_loop_im) Init(1) Optimization
2064 Enable loop invariant motion on trees
2067 Common Alias(floop-interchange)
2068 Enable loop interchange transforms. Same as -floop-interchange
2071 Common Report Var(flag_tree_loop_ivcanon) Init(1) Optimization
2072 Create canonical induction variables in loops
2075 Common Report Var(flag_tree_loop_optimize) Init(1) Optimization
2076 Enable loop optimizations on tree level
2078 ftree-parallelize-loops=
2079 Common Report Joined RejectNegative UInteger Var(flag_tree_parallelize_loops) Init(1)
2080 Enable automatic parallelization of loops
2083 Common Report Var(flag_tree_phiprop) Init(1) Optimization
2084 Enable hoisting loads from conditional pointers.
2087 Common Report Var(flag_tree_pre) Optimization
2088 Enable SSA-PRE optimization on trees
2091 Common Report Var(flag_tree_partial_pre) Optimization
2092 In SSA-PRE optimization on trees, enable partial-partial redundancy elimination
2095 Common Report Var(flag_tree_pta) Init(1) Optimization
2096 Perform function-local points-to analysis on trees.
2099 Common Report Var(flag_tree_reassoc) Init(1) Optimization
2100 Enable reassociation on tree level
2104 Does nothing. Preserved for backward compatibility.
2107 Common Report Var(flag_tree_sink) Optimization
2108 Enable SSA code sinking on trees
2111 Common Report Var(flag_tree_slsr) Optimization
2112 Perform straight-line strength reduction
2115 Common Report Var(flag_tree_sra) Optimization
2116 Perform scalar replacement of aggregates
2119 Common Report Var(flag_tree_ter) Optimization
2120 Replace temporary expressions in the SSA->normal pass
2123 Common Report Var(flag_tree_live_range_split) Optimization
2124 Perform live range splitting during the SSA->normal pass
2127 Common Report Var(flag_tree_vrp) Init(0) Optimization
2128 Perform Value Range Propagation on trees
2131 Common Report Var(flag_unit_at_a_time) Init(1) Optimization
2132 Compile whole compilation unit at a time
2135 Common Report Var(flag_unroll_loops) Optimization
2136 Perform loop unrolling when iteration count is known
2139 Common Report Var(flag_unroll_all_loops) Optimization
2140 Perform loop unrolling for all loops
2142 ; Nonzero means that loop optimizer may assume that the induction variables
2143 ; that control loops do not overflow and that the loops with nontrivial
2144 ; exit condition are not infinite
2145 funsafe-loop-optimizations
2146 Common Report Var(flag_unsafe_loop_optimizations) Optimization
2147 Allow loop optimizations to assume that the loops behave in normal way
2150 Common Report Var(flag_associative_math) SetByCombined
2151 Allow optimization for floating-point arithmetic which may change the
2152 result of the operation due to rounding.
2155 Common Report Var(flag_reciprocal_math) SetByCombined
2156 Same as -fassociative-math for expressions which include division.
2158 ; Nonzero means that unsafe floating-point math optimizations are allowed
2159 ; for the sake of speed. IEEE compliance is not guaranteed, and operations
2160 ; are allowed to assume that their arguments and results are "normal"
2161 ; (e.g., nonnegative for SQRT).
2162 funsafe-math-optimizations
2163 Common Report Var(flag_unsafe_math_optimizations) Optimization SetByCombined
2164 Allow math optimizations that may violate IEEE or ISO standards
2167 Common Report Var(flag_unswitch_loops) Optimization
2168 Perform loop unswitching
2171 Common Report Var(flag_unwind_tables) Optimization
2172 Just generate unwind tables for exception handling
2177 ; Positive if we should track variables, negative if we should run
2178 ; the var-tracking pass only to discard debug annotations, zero if
2179 ; we're not to run it. When flag_var_tracking == 2 (AUTODETECT_VALUE) it
2180 ; will be set according to optimize, debug_info_level and debug_hooks
2181 ; in process_options ().
2183 Common Report Var(flag_var_tracking) Init(2) Optimization
2184 Perform variable tracking
2186 ; Positive if we should track variables at assignments, negative if
2187 ; we should run the var-tracking pass only to discard debug
2188 ; annotations. When flag_var_tracking_assignments ==
2189 ; AUTODETECT_VALUE it will be set according to flag_var_tracking.
2190 fvar-tracking-assignments
2191 Common Report Var(flag_var_tracking_assignments) Init(2) Optimization
2192 Perform variable tracking by annotating assignments
2194 ; Nonzero if we should toggle flag_var_tracking_assignments after
2195 ; processing options and computing its default. */
2196 fvar-tracking-assignments-toggle
2197 Common Report Var(flag_var_tracking_assignments_toggle) Optimization
2198 Toggle -fvar-tracking-assignments
2200 ; Positive if we should track uninitialized variables, negative if
2201 ; we should run the var-tracking pass only to discard debug
2202 ; annotations. When flag_var_tracking_uninit == AUTODETECT_VALUE it
2203 ; will be set according to flag_var_tracking.
2204 fvar-tracking-uninit
2205 Common Report Var(flag_var_tracking_uninit) Optimization
2206 Perform variable tracking and also tag variables that are uninitialized
2209 Common Report Var(flag_tree_vectorize) Optimization
2210 Enable loop vectorization on trees
2212 ftree-vectorizer-verbose=
2213 Common RejectNegative Joined UInteger Var(common_deferred_options) Defer
2214 -ftree-vectorizer-verbose=<number> This switch is deprecated. Use -fopt-info instead.
2217 Common Report Var(flag_tree_slp_vectorize) Init(2) Optimization
2218 Enable basic block vectorization (SLP) on trees
2221 Common Report Var(flag_vect_cost_model) Optimization
2222 Enable use of cost model in vectorization
2224 ftree-vect-loop-version
2225 Common Report Var(flag_tree_vect_loop_version) Init(1) Optimization
2226 Enable loop versioning when doing loop vectorization on trees
2229 Common Report Var(flag_tree_scev_cprop) Init(1) Optimization
2230 Enable copy propagation of scalar-evolution information.
2232 ; -fverbose-asm causes extra commentary information to be produced in
2233 ; the generated assembly code (to make it more readable). This option
2234 ; is generally only of use to those who actually need to read the
2235 ; generated assembly code (perhaps while debugging the compiler itself).
2236 ; -fno-verbose-asm, the default, causes the extra information
2237 ; to not be added and is useful when comparing two assembler files.
2239 Common Report Var(flag_verbose_asm)
2240 Add extra commentary to assembler output
2243 Common Joined RejectNegative Enum(symbol_visibility) Var(default_visibility) Init(VISIBILITY_DEFAULT)
2244 -fvisibility=[default|internal|hidden|protected] Set the default symbol visibility
2247 Name(symbol_visibility) Type(enum symbol_visibility) UnknownError(unrecognized visibility value %qs)
2250 Enum(symbol_visibility) String(default) Value(VISIBILITY_DEFAULT)
2253 Enum(symbol_visibility) String(internal) Value(VISIBILITY_INTERNAL)
2256 Enum(symbol_visibility) String(hidden) Value(VISIBILITY_HIDDEN)
2259 Enum(symbol_visibility) String(protected) Value(VISIBILITY_PROTECTED)
2262 Common Report Var(flag_value_profile_transformations) Optimization
2263 Use expression value profiles in optimizations
2266 Common Report Var(flag_web) Init(2) Optimization
2267 Construct webs and split unrelated uses of single variable
2269 ftree-builtin-call-dce
2270 Common Report Var(flag_tree_builtin_call_dce) Init(0) Optimization
2271 Enable conditional dead code elimination for builtin calls
2274 Common Report Var(flag_whole_program) Init(0) Optimization
2275 Perform whole program optimizations
2278 Common Report Var(flag_wrapv) Optimization
2279 Assume signed arithmetic overflow wraps around
2281 fzero-initialized-in-bss
2282 Common Report Var(flag_zero_initialized_in_bss) Init(1)
2283 Put zero initialized data in the bss section
2286 Common JoinedOrMissing
2287 Generate debug information in default format
2290 Common JoinedOrMissing Negative(gdwarf-)
2291 Generate debug information in COFF format
2294 Common Joined UInteger Var(dwarf_version) Init(4) Negative(gstabs)
2295 Generate debug information in DWARF v2 (or later) format
2298 Common JoinedOrMissing
2299 Generate debug information in default extended format
2302 Common RejectNegative Var(debug_generate_pub_sections, 0) Init(-1)
2303 Don't generate DWARF pubnames and pubtypes sections.
2306 Common RejectNegative Var(debug_generate_pub_sections, 1)
2307 Generate DWARF pubnames and pubtypes sections.
2309 gno-record-gcc-switches
2310 Common RejectNegative Var(dwarf_record_gcc_switches,0) Init(1)
2311 Don't record gcc command line switches in DWARF DW_AT_producer.
2313 grecord-gcc-switches
2314 Common RejectNegative Var(dwarf_record_gcc_switches,1)
2315 Record gcc command line switches in DWARF DW_AT_producer.
2318 Common Driver RejectNegative Var(dwarf_split_debug_info,0) Init(0)
2319 Don't generate debug information in separate .dwo files
2322 Common Driver RejectNegative Var(dwarf_split_debug_info,1)
2323 Generate debug information in separate .dwo files
2326 Common JoinedOrMissing Negative(gstabs+)
2327 Generate debug information in STABS format
2330 Common JoinedOrMissing Negative(gvms)
2331 Generate debug information in extended STABS format
2334 Common RejectNegative Var(dwarf_strict,0) Init(0)
2335 Emit DWARF additions beyond selected version
2338 Common Report RejectNegative Var(dwarf_strict,1)
2339 Don't emit DWARF additions beyond selected version
2342 Common Report Var(flag_gtoggle)
2343 Toggle debug information generation
2346 Common JoinedOrMissing Negative(gxcoff)
2347 Generate debug information in VMS format
2350 Common JoinedOrMissing Negative(gxcoff+)
2351 Generate debug information in XCOFF format
2354 Common JoinedOrMissing Negative(gcoff)
2355 Generate debug information in extended XCOFF format
2358 Driver Joined Separate
2361 Common Joined Var(plugindir_string) Init(0)
2362 -iplugindir=<dir> Set <dir> to be the default plugin directory
2365 Common Joined Separate RejectDriver Var(imultiarch) Init(0)
2366 -imultiarch <dir> Set <dir> to be the multiarch include subdirectory
2369 Driver Joined Separate
2374 no-canonical-prefixes
2387 Common Driver Joined Separate Var(asm_file_name) MissingArgError(missing filename after %qs)
2388 -o <file> Place output into <file>
2391 Common Var(profile_flag)
2392 Enable function profiling
2395 Driver Var(pass_exit_codes)
2398 Common Alias(Wpedantic)
2401 Common Var(flag_pedantic_errors)
2402 Like -pedantic but issue them as errors
2408 Driver Var(use_pipes)
2411 Driver JoinedOrMissing Var(print_file_name)
2413 print-libgcc-file-name
2416 print-multi-directory
2417 Driver Var(print_multi_directory)
2420 Driver Var(print_multi_lib)
2422 print-multi-os-directory
2423 Driver Var(print_multi_os_directory)
2426 Driver Var(print_multiarch)
2429 Driver JoinedOrMissing Var(print_prog_name)
2432 Driver Var(print_search_dirs)
2435 Driver Var(print_sysroot)
2437 print-sysroot-headers-suffix
2438 Driver Var(print_sysroot_headers_suffix)
2441 Common Var(quiet_flag) RejectDriver
2442 Do not display functions compiled or elapsed time
2460 Driver Var(report_times)
2463 Driver JoinedOrMissing
2466 Driver Joined Separate
2470 ; C option, but driver must not handle as "-u ndef".
2473 Common Driver Var(verbose_flag)
2474 Enable verbose output
2477 Common Var(version_flag) RejectDriver
2478 Display the compiler's version
2481 Common Var(inhibit_warnings)
2485 Driver Separate Var(wrapper_string)
2488 Driver Joined Separate
2491 Driver RejectNegative Negative(pie)
2492 Create a shared library
2498 Driver Separate Alias(specs=)
2511 ; Documented for Fortran, but always accepted by driver.
2518 ; Documented for Go, but always accepted by driver.
2530 Driver RejectNegative Negative(shared)
2531 Create a position independent executable
2534 Driver Joined Separate
2536 ; This comment is to ensure we retain the blank line above.