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 ; 0 means straightforward implementation of complex divide acceptable.
41 ; 1 means wide ranges of inputs must work for complex divide.
42 ; 2 means C99-like requirements for complex multiply and divide.
44 int flag_complex_method = 1
46 ; Nonzero if subexpressions must be evaluated from left-to-right.
48 int flag_evaluation_order = 0
50 ; Language specific warning pass for unused results.
52 bool flag_warn_unused_result = false
57 ; Nonzero if we should write GIMPLE bytecode for link-time optimization.
61 ; True to warn about any objects definitions whose size is larger
62 ; than N bytes. Also want about function definitions whose returned
63 ; values are larger than N bytes, where N is 'larger_than_size'.
68 HOST_WIDE_INT larger_than_size
70 ; True to warn about any function whose frame size is larger
73 bool warn_frame_larger_than
76 HOST_WIDE_INT frame_larger_than_size
78 ; Nonzero means we should be saving declaration info into a .X file.
80 int flag_gen_aux_info = 0
82 ; Nonzero if we are compiling code for a shared library, zero for
87 ; These two are really VEC(char_p,heap) *.
90 void *flag_instrument_functions_exclude_functions
93 void *flag_instrument_functions_exclude_files
95 ; Generic structs (e.g. templates not explicitly specialized)
96 ; may not have a compilation unit associated with them, and so
97 ; may need to be treated differently from ordinary structs.
99 ; Structs only handled by reference (indirectly), will also usually
100 ; not need as much debugging information.
103 enum debug_struct_file debug_struct_ordinary[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
106 enum debug_struct_file debug_struct_generic[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
108 ; True if we should exit after parsing options.
110 bool exit_after_options
112 ; Type(s) of debugging information we are producing (if any). See
113 ; flag-types.h for the definitions of the different possible types of
114 ; debugging information.
116 enum debug_info_type write_symbols = NO_DEBUG
118 ; Level of debugging information we are producing. See flag-types.h
119 ; for the definitions of the different possible levels.
121 enum debug_info_levels debug_info_level = DINFO_LEVEL_NONE
123 ; Whether to generate line number table. Normally set at DINFO_LEVEL_NORMAL
124 ; or above; can also be set for DINFO_LEVEL_TERSE with -gmlt.
126 bool generate_debug_line_table = false
128 ; Nonzero means use GNU-only extensions in the generated symbolic
129 ; debugging information. Currently, this only has an effect when
130 ; write_symbols is set to DBX_DEBUG, XCOFF_DEBUG, or DWARF_DEBUG.
132 bool use_gnu_debug_info_extensions
134 ; Original value of maximum field alignment in bytes, specified via
135 ; -fpack-struct=<value>.
137 unsigned int initial_max_fld_align = TARGET_DEFAULT_PACK_STRUCT
140 enum vect_verbosity_levels user_vect_verbosity_level = MAX_VERBOSITY_LEVEL
142 ; Type of stack check.
144 enum stack_check_type flag_stack_check = NO_STACK_CHECK
146 ; -dA causes debug commentary information to be produced in
147 ; the generated assembly code (to make it more readable). This option
148 ; is generally only of use to those who actually need to read the
149 ; generated assembly code (perhaps while debugging the compiler itself).
150 ; Currently, this switch is only used by dwarf2out.c; however, it is intended
151 ; to be a catchall for printing debug information in the assembler file.
155 ; -dP causes the rtl to be emitted as a comment in assembly.
157 int flag_dump_rtl_in_asm
159 ; Whether -da was passed (used only in handle_common_deferred_options).
161 bool flag_dump_all_passed
163 ; Other flags saying which kinds of debugging dump have been requested.
166 int rtl_dump_and_exit
169 int flag_print_asm_name
172 enum graph_dump_types graph_dump_format = no_graph
174 ; Name of top-level original source file (what was input to cpp).
175 ; This comes from the #-command at the beginning of the actual input.
176 ; If there isn't any there, then this is the cc1 input file name.
178 const char *main_input_filename
180 ; Pointer to base name in main_input_filename, with directories and a
181 ; single final extension removed, and the length of this base
185 const char *main_input_basename
188 int main_input_baselength
190 ; Which options have been printed by --help.
194 ; Which enums have been printed by --help. 0 = not printed, no
195 ; relevant options seen, 1 = relevant option seen, not yet printed, 2
198 char *help_enum_printed
200 ; The number of columns for --help output.
202 unsigned int help_columns
204 ; Whether this options structure has been through finish_options
206 bool flag_opts_finished
218 Driver Alias(coverage)
224 Common Separate Alias(d)
227 Common Joined Alias(d)
230 Common Separate Alias(dumpbase)
233 Common Separate Alias(dumpdir)
236 Driver Separate Alias(e)
239 Driver Joined Alias(e)
242 Common Warning Alias(Wextra)
245 Driver Separate Alias(Xassembler)
248 Driver JoinedOrMissing Alias(Xassembler)
251 Driver Separate Alias(Xlinker)
254 Driver JoinedOrMissing Alias(Xlinker)
257 Driver Separate Alias(u)
260 Driver Joined Alias(u)
263 Common Driver Var(help_flag)
264 Display this information
267 Common Driver Report Joined
268 --help=<class> Display descriptions of a specific class of options. <class> is one or more of optimizers, target, warnings, undocumented, params
271 Driver Separate Alias(x)
274 Driver Joined Alias(x)
277 Driver Separate Alias(L)
280 Driver Joined Alias(L)
282 -no-canonical-prefixes
283 Driver Alias(no-canonical-prefixes)
286 Driver Alias(canonical-prefixes)
288 -no-standard-libraries
289 Driver Alias(nostdlib)
298 Common Driver Separate Alias(o) MissingArgError(missing filename after %qs)
301 Common Driver Joined Alias(o) MissingArgError(missing filename after %qs)
304 Driver Alias(pass-exit-codes)
307 Common Alias(pedantic)
310 Common Alias(pedantic-errors)
319 Driver Separate Alias(B)
322 Driver JoinedOrMissing Alias(B)
328 Driver Separate Alias(print-file-name=)
331 Driver JoinedOrMissing Alias(print-file-name=)
333 -print-libgcc-file-name
334 Driver Alias(print-libgcc-file-name)
336 -print-multi-directory
337 Driver Alias(print-multi-directory)
340 Driver Alias(print-multi-lib)
342 -print-multi-os-directory
343 Driver Alias(print-multi-os-directory)
346 Driver Separate Alias(print-prog-name=)
349 Driver JoinedOrMissing Alias(print-prog-name=)
352 Driver Alias(print-search-dirs)
355 Driver Alias(print-sysroot)
357 -print-sysroot-headers-suffix
358 Driver Alias(print-sysroot-headers-suffix)
364 Driver Alias(save-temps)
370 Driver Separate Alias(specs=)
373 Driver Joined Alias(specs=)
379 Driver Alias(symbolic)
383 Alias for --help=target
391 ;; The driver used to convert options such as --help into forms such
392 ;; as -fhelp; the following four entries are for compatibility with
393 ;; any direct uses of those (undocumented) -f forms
395 Common Driver Alias(-help)
398 Common Driver Joined Alias(-help=)
401 Common Driver Alias(-target-help)
404 Common Driver Alias(-version)
408 --param <param>=<value> Set parameter <param> to value. See below for a complete list of parameters
411 Common Joined Alias(-param)
414 Driver Separate Alias(-sysroot=)
417 Driver JoinedOrMissing
423 Driver Joined Separate
429 Driver Joined Separate
435 Common JoinedOrMissing Optimization
436 -O<number> Set optimization level to <number>
440 Optimize for space rather than speed
444 Optimize for speed disregarding exact standards compliance
456 Driver Joined Separate
462 Driver Joined Separate
483 Common RejectNegative Warning Alias(Wextra)
484 This switch is deprecated; use -Wextra instead
487 Driver JoinedOrMissing
490 Driver JoinedOrMissing
493 Driver JoinedOrMissing
496 Common Var(warn_aggregate_return) Warning
497 Warn about returning structures, unions or arrays
500 Common Var(warn_array_bounds) Warning
501 Warn if an array is accessed out of bounds
504 Common Var(warn_attributes) Init(1) Warning
505 Warn about inappropriate attribute usage
508 Common Var(warn_cast_align) Warning
509 Warn about pointer casts which increase alignment
512 Common Var(warn_cpp) Init(1) Warning
513 Warn when a #warning directive is encountered
515 Wdeprecated-declarations
516 Common Var(warn_deprecated_decl) Init(1) Warning
517 Warn about uses of __attribute__((deprecated)) declarations
519 Wdisabled-optimization
520 Common Var(warn_disabled_optimization) Warning
521 Warn when an optimization pass is disabled
524 Common Var(warnings_are_errors)
525 Treat all warnings as errors
529 Treat specified warning as error
532 Common Var(extra_warnings) Warning
533 Print extra (possibly unwanted) warnings
536 Common Var(flag_fatal_errors)
537 Exit on the first error occurred
540 Common RejectNegative Joined UInteger
541 -Wframe-larger-than=<number> Warn if a function's stack frame requires more than <number> bytes
544 Common Var(warn_inline) Warning
545 Warn when an inlined function cannot be inlined
548 Common RejectNegative Joined Warning Undocumented Alias(Wlarger-than=)
551 Common RejectNegative Joined UInteger Warning
552 -Wlarger-than=<number> Warn if an object is larger than <number> bytes
554 Wunsafe-loop-optimizations
555 Common Var(warn_unsafe_loop_optimizations) Warning
556 Warn if the loop cannot be optimized due to nontrivial assumptions.
559 Common Var(warn_missing_noreturn) Warning
560 Warn about functions which might be candidates for __attribute__((noreturn))
563 Common Var(warn_mudflap) Init(1) Warning
564 Warn about constructs not instrumented by -fmudflap
567 Common Var(warn_overflow) Init(1) Warning
568 Warn about overflow in arithmetic expressions
571 Common Var(warn_packed) Warning
572 Warn when the packed attribute has no effect on struct layout
575 Common Var(warn_padded) Warning
576 Warn when padding is required to align structure members
579 Common Var(warn_ripa_opt_mismatch) Warning
580 Warn if primary and auxiliary modules have mismatched command line options
583 Common Var(warn_self_assign) Init(0) Warning
584 Warn when a variable is assigned to itself
587 Common Var(warn_shadow) Warning
588 Warn when one local variable shadows another
591 Common Var(warn_shadow_local) Warning
592 Warn when one local variable shadows another local variable or parameter
594 Wshadow-compatible-local
595 Common Var(warn_shadow_compatible_local) Warning
596 Warn when one local variable shadows another local variable or parameter
600 Common Var(warn_stack_protect) Warning
601 Warn when not issuing stack smashing protection for some reason
605 Warn about code which might break strict aliasing rules
608 Common Joined RejectNegative UInteger Var(warn_strict_aliasing) Init(-1) Warning
609 Warn about code which might break strict aliasing rules
613 Warn about optimizations that assume that signed overflow is undefined
616 Common Joined RejectNegative UInteger Var(warn_strict_overflow) Init(-1) Warning
617 Warn about optimizations that assume that signed overflow is undefined
619 Wsuggest-attribute=const
620 Common Var(warn_suggest_attribute_const) Warning
621 Warn about functions which might be candidates for __attribute__((const))
623 Wsuggest-attribute=pure
624 Common Var(warn_suggest_attribute_pure) Warning
625 Warn about functions which might be candidates for __attribute__((pure))
627 Wsuggest-attribute=noreturn
628 Common Var(warn_suggest_attribute_noreturn) Warning
629 Warn about functions which might be candidates for __attribute__((noreturn))
632 Common Var(warn_switch) Warning
633 Warn about enumerated switches, with no default, missing a case
636 Common Var(warn_switch_default) Warning
637 Warn about enumerated switches missing a \"default:\" statement
640 Common Var(warn_switch_enum) Warning
641 Warn about all enumerated switches missing a specific case
644 Common Var(warn_system_headers) Warning
645 Do not suppress warnings from system headers
648 Common Var(warn_trampolines) Warning
649 Warn whenever a trampoline is generated
652 Common Var(warn_thread_safety) Warning
653 Warn about potential thread safety issues when the code is annotated with thread safety attributes
655 Wthread-unguarded-var
656 Common Var(warn_thread_unguarded_var) Init(1) Warning
657 Warn about shared variables not properly protected by locks specified in the attributes
659 Wthread-unguarded-func
660 Common Var(warn_thread_unguarded_func) Init(1) Warning
661 Warn about function calls not properly protected by locks specified in the attributes
663 Wthread-mismatched-lock-order
664 Common Var(warn_thread_mismatched_lock_order) Init(1) Warning
665 Warn about lock acquisition order inconsistent with what specified in the attributes
667 Wthread-mismatched-lock-acq-rel
668 Common Var(warn_thread_mismatched_lock_acq_rel) Init(1) Warning
669 Warn about mismatched lock acquisition and release
671 Wthread-reentrant-lock
672 Common Var(warn_thread_reentrant_lock) Init(1) Warning
673 Warn about a lock being acquired recursively
675 Wthread-unsupported-lock-name
676 Common Var(warn_unsupported_lock_name) Init(0) Warning
677 Warn about uses of unsupported lock names in attributes
679 Wthread-attr-bind-param
680 Common Var(warn_thread_attr_bind_param) Init(1) Warning
681 Make the thread safety analysis try to bind the function parameters used in the attributes
683 Wthread-warn-optimization
684 Common Var(warn_thread_optimization) Init(1) Warning
685 Warn when optimizations invalidate the thread safety analysis.
688 Common Var(warn_type_limits) Init(-1) Warning
689 Warn if a comparison is always true or always false due to the limited range of the data type
692 Common Var(warn_uninitialized) Init(-1) Warning
693 Warn about uninitialized automatic variables
696 Common Var(warn_maybe_uninitialized) Warning
697 Warn about maybe uninitialized automatic variables
701 Does nothing. Preserved for backward compatibility.
704 Common Var(warn_unused) Init(0) Warning
705 Enable all -Wunused- warnings
707 Wunused-but-set-parameter
708 Common Var(warn_unused_but_set_parameter) Init(-1) Warning
709 Warn when a function parameter is only set, otherwise unused
711 Wunused-but-set-variable
712 Common Var(warn_unused_but_set_variable) Init(-1) Warning
713 Warn when a variable is only set, otherwise unused
716 Common Var(warn_unused_function) Init(-1) Warning
717 Warn when a function is unused
720 Common Var(warn_unused_label) Init(-1) Warning
721 Warn when a label is unused
724 Common Var(warn_unused_parameter) Init(-1) Warning
725 Warn when a function parameter is unused
728 Common Var(warn_unused_value) Init(-1) Warning
729 Warn when an expression value is unused
732 Common Var(warn_unused_variable) Init(-1) Warning
733 Warn when a variable is unused
736 Common Var(warn_coverage_mismatch) Init(1) Warning
737 Warn in case profiles in -fprofile-use do not match
752 Common Separate Var(aux_info_file_name)
753 -aux-info <file> Emit declaration information into <file>
756 Common Joined Alias(aux-info)
759 Common Separate RejectDriver Var(aux_base_name)
762 Common Separate RejectDriver
772 -d<letters> Enable dumps from specific passes of the compiler
775 Common Separate Var(dump_base_name)
776 -dumpbase <file> Set the file basename to be used for dumps
779 Common Separate Var(dump_dir_name)
780 -dumpdir <dir> Set the directory name to be used for dumps
792 Driver Joined Separate
794 ; This option has historically been passed down to the linker by an
795 ; accident of a %{e*} spec, so ensure it continues to be passed down
796 ; as a single option. The supported option for this purpose is
797 ; -rdynamic. See PR 47390.
801 ; The version of the C++ ABI in use. The following values are allowed:
803 ; 0: The version of the ABI believed most conformant with the C++ ABI
804 ; specification. This ABI may change as bugs are discovered and fixed.
805 ; Therefore, 0 will not necessarily indicate the same ABI in different
808 ; 1: The version of the ABI first used in G++ 3.2.
810 ; 2: The version of the ABI first used in G++ 3.4 (and current default).
812 ; 3: The version of the ABI that fixes the missing underscore
813 ; in template non-type arguments of pointer type.
815 ; 4: The version of the ABI that introduces unambiguous mangling of
816 ; vector types. First selectable in G++ 4.5.
818 ; 5: The version of the ABI that ignores attribute const/noreturn
819 ; in function pointer mangling, and corrects mangling of decltype and
820 ; function parameters used in other parameters and the return type.
821 ; First selectable in G++ 4.6.
823 ; Additional positive integers will be assigned as new versions of
824 ; the ABI become the default version of the ABI.
826 Common Joined RejectNegative UInteger Var(flag_abi_version) Init(2)
829 Common Report Var(align_functions,0) Optimization UInteger
830 Align the start of functions
833 Common RejectNegative Joined UInteger Var(align_functions)
836 Common Report Var(align_jumps,0) Optimization UInteger
837 Align labels which are only reached by jumping
840 Common RejectNegative Joined UInteger Var(align_jumps)
843 Common Report Var(align_labels,0) Optimization UInteger
847 Common RejectNegative Joined UInteger Var(align_labels)
850 Common Report Var(align_loops,0) Optimization UInteger
851 Align the start of loops
854 Common RejectNegative Joined UInteger Var(align_loops)
858 Does nothing. Preserved for backward compatibility.
862 Does nothing. Preserved for backward compatibility.
864 fargument-noalias-global
866 Does nothing. Preserved for backward compatibility.
868 fargument-noalias-anything
870 Does nothing. Preserved for backward compatibility.
872 fasynchronous-unwind-tables
873 Common Report Var(flag_asynchronous_unwind_tables) Optimization
874 Generate unwind tables that are exact at each instruction boundary
877 Common Report Var(flag_auto_inc_dec) Init(1)
878 Generate auto-inc/dec instructions
880 ; -fcheck-bounds causes gcc to generate array bounds checks.
881 ; For C, C++ and ObjC: defaults off.
882 ; For Java: defaults to on.
883 ; For Fortran: defaults to off.
885 Common Report Var(flag_bounds_check)
886 Generate code to check bounds before indexing arrays
889 Common Report Var(flag_branch_on_count_reg) Init(1) Optimization
890 Replace add, compare, branch with branch on count register
892 fbranch-probabilities
893 Common Report Var(flag_branch_probabilities) Optimization
894 Use profiling information for branch probabilities
896 fbranch-target-load-optimize
897 Common Report Var(flag_branch_target_load_optimize) Optimization
898 Perform branch target load optimization before prologue / epilogue threading
900 fbranch-target-load-optimize2
901 Common Report Var(flag_branch_target_load_optimize2) Optimization
902 Perform branch target load optimization after prologue / epilogue threading
905 Common Report Var(flag_btr_bb_exclusive) Optimization
906 Restrict target load migration not to re-use registers in any basic block
909 Common Joined RejectNegative Var(common_deferred_options) Defer
910 -fcall-saved-<register> Mark <register> as being preserved across functions
913 Common Joined RejectNegative Var(common_deferred_options) Defer
914 -fcall-used-<register> Mark <register> as being corrupted by function calls
916 ; Nonzero for -fcaller-saves: allocate values in regs that need to
917 ; be saved across function calls, if that produces overall better code.
918 ; Optional now, so people can test it.
920 Common Report Var(flag_caller_saves) Optimization
921 Save registers around function calls
923 fcallgraph-profiles-sections
924 Common Report Var(flag_callgraph_profiles_sections) Init(0)
925 Generate .note.callgraph.text sections listing callees and edge counts.
928 Common Report Var(flag_check_data_deps)
929 Compare the results of several data dependence analyzers.
931 fcombine-stack-adjustments
932 Common Report Var(flag_combine_stack_adjustments) Optimization
933 Looks for opportunities to reduce stack adjustments and stack references.
936 Common Report Var(flag_no_common,0) Optimization
937 Do not put uninitialized globals in the common section
941 ; Converted by the driver to -fcompare-debug= options.
944 Common Driver JoinedOrMissing RejectNegative Var(flag_compare_debug_opt)
945 -fcompare-debug[=<opts>] Compile with and without e.g. -gtoggle, and compare the final-insns dump
947 fcompare-debug-second
948 Common Driver RejectNegative Var(flag_compare_debug)
949 Run only the second compilation of -fcompare-debug
952 Common Report Var(flag_compare_elim_after_reload) Optimization
953 Perform comparison elimination after register allocation has finished
956 Common Var(flag_conserve_stack) Optimization
957 Do not perform optimizations increasing noticeably stack usage
960 Common Report Var(flag_cprop_registers) Optimization
961 Perform a register copy-propagation optimization pass
964 Common Report Var(flag_crossjumping) Optimization
965 Perform cross-jumping optimization
968 Common Report Var(flag_cse_follow_jumps) Optimization
969 When running CSE, follow jumps to their targets
973 Does nothing. Preserved for backward compatibility.
976 Common Report Var(flag_cx_limited_range) Optimization SetByCombined
977 Omit range reduction step when performing complex division
980 Common Report Var(flag_cx_fortran_rules) Optimization
981 Complex multiplication and division follow Fortran rules
984 Common Report Var(flag_data_sections) Optimization
985 Place data items into their own section
988 Common Report Var(common_deferred_options) Defer
989 List all available debugging counters with their limits and counts.
992 Common RejectNegative Joined Var(common_deferred_options) Defer
993 -fdbg-cnt=<counter>:<limit>[,<counter>:<limit>,...] Set the debug counter limit.
996 Common Joined RejectNegative Var(common_deferred_options) Defer
997 Map one directory name to another in debug information
999 ; Nonzero for -fdefer-pop: don't pop args after each function call
1000 ; instead save them up to pop many calls' args with one insns.
1002 Common Report Var(flag_defer_pop) Optimization
1003 Defer popping functions args from stack until later
1006 Common Report Var(flag_delayed_branch) Optimization
1007 Attempt to fill delay slots of branch instructions
1009 fdelete-null-pointer-checks
1010 Common Report Var(flag_delete_null_pointer_checks) Init(1) Optimization
1011 Delete useless null pointer checks
1014 Common Report Var(flag_devirtualize) Optimization
1015 Try to convert virtual calls to direct ones.
1017 fdiagnostics-show-location=
1018 Common Joined RejectNegative Enum(diagnostic_prefixing_rule)
1019 -fdiagnostics-show-location=[once|every-line] How often to emit source location at the beginning of line-wrapped diagnostics
1021 ; Required for these enum values.
1026 Name(diagnostic_prefixing_rule) Type(int)
1029 Enum(diagnostic_prefixing_rule) String(once) Value(DIAGNOSTICS_SHOW_PREFIX_ONCE)
1032 Enum(diagnostic_prefixing_rule) String(every-line) Value(DIAGNOSTICS_SHOW_PREFIX_EVERY_LINE)
1034 fdiagnostics-show-option
1035 Common Var(flag_diagnostics_show_option) Init(1)
1036 Amend appropriate diagnostic messages with the command line option that controls them
1039 Common Joined RejectNegative Var(common_deferred_options) Defer
1040 -fdisable-[tree|rtl|ipa]-<pass>=range1+range2 disables an optimization pass
1043 Common Joined RejectNegative Var(common_deferred_options) Defer
1044 -fenable-[tree|rtl|ipa]-<pass>=range1+range2 enables an optimization pass
1047 Common Joined RejectNegative Var(common_deferred_options) Defer
1048 -fdump-<type> Dump various compiler internals to a file
1051 Driver RejectNegative
1054 Common RejectNegative Joined Var(flag_dump_final_insns)
1055 -fdump-final-insns=filename Dump to filename the insns at the end of translation
1058 Common RejectNegative Joined Var(flag_dump_go_spec)
1059 -fdump-go-spec=filename Write all declarations to file as Go code
1062 Common Report Var(flag_dump_noaddr)
1063 Suppress output of addresses in debugging dumps
1066 Common Var(flag_dump_passes) Init(0)
1067 Dump optimization passes
1070 Common Report Var(flag_dump_unnumbered)
1071 Suppress output of instruction numbers, line number notes and addresses in debugging dumps
1073 fdump-unnumbered-links
1074 Common Report Var(flag_dump_unnumbered_links)
1075 Suppress output of previous and next insn numbers in debugging dumps
1078 Common Report Var(flag_dwarf2_cfi_asm) Init(HAVE_GAS_CFI_DIRECTIVE)
1079 Enable CFI tables via GAS assembler directives.
1082 Common Report Var(flag_profile_reusedist)
1083 Profile generation for memory reuse distance.
1086 Common Report Var(flag_optimize_locality)
1087 Optimization based on improving memory reference locality.
1090 Common Report Var(flag_dyn_ipa)
1091 Perform Dynamic Inter-Procedural Analysis.
1093 fripa-disallow-asm-modules
1094 Common Report Var(flag_ripa_disallow_asm_modules)
1095 Don't import an auxiliary module if it contains asm statements
1097 fripa-disallow-opt-mismatch
1098 Common Report Var(flag_ripa_disallow_opt_mismatch)
1099 Don't import an auxiliary module if the command line options mismatch with the primary module
1101 fripa-no-promote-always-inline-func
1102 Common Report Var(flag_ripa_no_promote_always_inline) Init(0)
1103 Don't promote always inline static functions assuming they
1104 will be inlined and no copy is needed.
1106 fripa-peel-size-limit
1107 Common Report Var(flag_ripa_peel_size_limit) Init(1) Optimization
1108 Limit non-const non-FP loop peeling under dynamic IPA estimates of large code footprint
1110 fripa-unroll-size-limit
1111 Common Report Var(flag_ripa_unroll_size_limit) Init(1) Optimization
1112 Limit non-const non-FP loop unrolling under dynamic IPA estimates of large code footprint
1115 Common Joined RejectNegative Var(lipo_inc_path_pattern)
1116 Substitute substring in include paths with a new string to allow reuse profile data
1119 Common Report Var(flag_early_inlining) Init(1) Optimization
1120 Perform early inlining
1122 feliminate-dwarf2-dups
1123 Common Report Var(flag_eliminate_dwarf2_dups)
1124 Perform DWARF2 duplicate elimination
1127 Common Report Var(flag_ipa_sra) Init(0) Optimization
1128 Perform interprocedural reduction of aggregates
1130 feliminate-unused-debug-symbols
1131 Common Report Var(flag_debug_only_used_symbols)
1132 Perform unused type elimination in debug info
1134 feliminate-unused-debug-types
1135 Common Report Var(flag_eliminate_unused_debug_types) Init(1)
1136 Perform unused type elimination in debug info
1138 femit-class-debug-always
1139 Common Report Var(flag_emit_class_debug_always) Init(0)
1140 Do not suppress C++ class debug information.
1143 Common Report Var(flag_enable_icf_debug)
1144 Generate debug information to support Identical Code Folding (ICF)
1147 Common Report Var(flag_exceptions) Optimization
1148 Enable exception handling
1150 fexpensive-optimizations
1151 Common Report Var(flag_expensive_optimizations) Optimization
1152 Perform a number of minor, expensive optimizations
1155 Common Joined RejectNegative Enum(excess_precision) Var(flag_excess_precision_cmdline) Init(EXCESS_PRECISION_DEFAULT)
1156 -fexcess-precision=[fast|standard] Specify handling of excess floating-point precision
1159 Name(excess_precision) Type(enum excess_precision) UnknownError(unknown excess precision style %qs)
1162 Enum(excess_precision) String(fast) Value(EXCESS_PRECISION_FAST)
1165 Enum(excess_precision) String(standard) Value(EXCESS_PRECISION_STANDARD)
1171 Common Report Var(flag_finite_math_only) Optimization SetByCombined
1172 Assume no NaNs or infinities are generated
1175 Common Joined RejectNegative Var(common_deferred_options) Defer
1176 -ffixed-<register> Mark <register> as being unavailable to the compiler
1179 Common Report Var(flag_float_store) Optimization
1180 Don't allocate floats and doubles in extended-precision registers
1184 Does nothing. Preserved for backward compatibility.
1187 Common Report Var(flag_forward_propagate) Optimization
1188 Perform a forward propagation pass on RTL
1191 Common Joined RejectNegative Enum(fp_contract_mode) Var(flag_fp_contract_mode) Init(FP_CONTRACT_FAST)
1192 -ffp-contract=[off|on|fast] Perform floating-point expression contraction.
1195 Name(fp_contract_mode) Type(enum fp_contract_mode) UnknownError(unknown floating point contraction style %qs)
1198 Enum(fp_contract_mode) String(off) Value(FP_CONTRACT_OFF)
1200 ; Not implemented, fall back to conservative FP_CONTRACT_OFF.
1202 Enum(fp_contract_mode) String(on) Value(FP_CONTRACT_OFF)
1205 Enum(fp_contract_mode) String(fast) Value(FP_CONTRACT_FAST)
1207 ; Nonzero means don't put addresses of constant functions in registers.
1208 ; Used for compiling the Unix kernel, where strange substitutions are
1209 ; done on the assembly output.
1211 Common Report Var(flag_no_function_cse,0)
1212 Allow function addresses to be held in registers
1215 Common Report Var(flag_function_sections)
1216 Place each function into its own section
1219 Common Report Var(flag_gcse) Optimization
1220 Perform global common subexpression elimination
1223 Common Report Var(flag_gcse_lm) Init(1) Optimization
1224 Perform enhanced load motion during global common subexpression elimination
1227 Common Report Var(flag_gcse_sm) Init(0) Optimization
1228 Perform store motion after global common subexpression elimination
1231 Common Report Var(flag_gcse_las) Init(0) Optimization
1232 Perform redundant load after store elimination in global common subexpression
1236 Common Report Var(flag_gcse_after_reload) Optimization
1237 Perform global common subexpression elimination after register allocation
1240 ; This option is not documented yet as its semantics will change.
1242 Common Report Var(flag_graphite)
1243 Enable in and out of Graphite representation
1246 Common Report Var(flag_graphite_identity) Optimization
1247 Enable Graphite Identity transformation
1249 floop-parallelize-all
1250 Common Report Var(flag_loop_parallelize_all) Optimization
1251 Mark all loops as parallel
1254 Common Report Var(flag_loop_strip_mine) Optimization
1255 Enable Loop Strip Mining transformation
1258 Common Report Var(flag_loop_interchange) Optimization
1259 Enable Loop Interchange transformation
1262 Common Report Var(flag_loop_block) Optimization
1263 Enable Loop Blocking transformation
1266 Common Report Var(flag_loop_flatten) Optimization
1267 Enable Loop Flattening transformation
1269 fstrict-volatile-bitfields
1270 Common Report Var(flag_strict_volatile_bitfields) Init(-1)
1271 Force bitfield accesses to match their type width
1273 fguess-branch-probability
1274 Common Report Var(flag_guess_branch_prob) Optimization
1275 Enable guessing of branch probabilities
1277 ; Nonzero means ignore `#ident' directives. 0 means handle them.
1278 ; Generate position-independent code for executables if possible
1279 ; On SVR4 targets, it also controls whether or not to emit a
1280 ; string identifying the compiler.
1282 Common Report Var(flag_no_ident,0)
1283 Process #ident directives
1286 Common Report Var(flag_if_conversion) Optimization
1287 Perform conversion of conditional jumps to branchless equivalents
1290 Common Report Var(flag_if_conversion2) Optimization
1291 Perform conversion of conditional jumps to conditional execution
1293 ftree-loop-if-convert
1294 Common Report Var(flag_tree_loop_if_convert) Init(-1) Optimization
1295 Convert conditional jumps in innermost loops to branchless equivalents
1297 ftree-loop-if-convert-stores
1298 Common Report Var(flag_tree_loop_if_convert_stores) Optimization
1299 Also if-convert conditional jumps containing memory writes
1301 ; -finhibit-size-directive inhibits output of .size for ELF.
1302 ; This is used only for compiling crtstuff.c,
1303 ; and it may be extended to other effects
1304 ; needed for crtstuff.c on other systems.
1305 finhibit-size-directive
1306 Common Report Var(flag_inhibit_size_directive)
1307 Do not generate .size directives
1310 Common Report Var(flag_indirect_inlining)
1311 Perform indirect inlining
1313 ; Nonzero means that functions declared `inline' will be treated
1314 ; as `static'. Prevents generation of zillions of copies of unused
1315 ; static inline functions; instead, `inlines' are written out
1316 ; only when actually used. Used in conjunction with -g. Also
1317 ; does the right thing with #pragma interface.
1319 Common Report Var(flag_no_inline,0) Init(0)
1320 Pay attention to the \"inline\" keyword
1322 finline-small-functions
1323 Common Report Var(flag_inline_small_functions) Optimization
1324 Integrate simple functions into their callers when code size is known to not growth
1327 Common Report Var(flag_inline_functions) Optimization
1328 Integrate simple functions into their callers
1330 finline-functions-called-once
1331 Common Report Var(flag_inline_functions_called_once) Init(1) Optimization
1332 Integrate functions called once into their callers
1335 Common RejectNegative Joined Alias(finline-limit=)
1338 Common RejectNegative Joined UInteger
1339 -finline-limit=<number> Limit the size of inlined functions to <number>
1342 Common Report Var(flag_inline_hot_caller) Init(1) Optimization
1343 Consider inlining cold callsites if the caller includes hot code
1345 finstrument-functions
1346 Common Report Var(flag_instrument_function_entry_exit)
1347 Instrument function entry and exit with profiling calls
1349 finstrument-functions-exclude-function-list=
1350 Common RejectNegative Joined
1351 -finstrument-functions-exclude-function-list=name,... Do not instrument listed functions
1353 finstrument-functions-exclude-file-list=
1354 Common RejectNegative Joined
1355 -finstrument-functions-exclude-file-list=filename,... Do not instrument functions listed in files
1358 Common Report Var(flag_ipa_cp) Optimization
1359 Perform Interprocedural constant propagation
1362 Common Report Var(flag_ipa_cp_clone) Optimization
1363 Perform cloning to make Interprocedural constant propagation stronger
1366 Common Report Var(flag_ipa_profile) Init(0) Optimization
1367 Perform interprocedural profile propagation
1370 Common Report Var(flag_ipa_pta) Init(0) Optimization
1371 Perform interprocedural points-to analysis
1374 Common Report Var(flag_ipa_pure_const) Init(0) Optimization
1375 Discover pure and const functions
1378 Common Report Var(flag_ipa_reference) Init(0) Optimization
1379 Discover readonly and non addressable static variables
1382 Common Report Var(flag_ipa_matrix_reorg) Optimization
1383 Perform matrix layout flattening and transposing based
1384 on profiling information.
1387 Common Report Var(flag_ipa_struct_reorg)
1388 Perform structure layout optimizations based
1389 on profiling information.
1392 Common Joined RejectNegative Enum(ira_algorithm) Var(flag_ira_algorithm) Init(IRA_ALGORITHM_CB)
1393 -fira-algorithm=[CB|priority] Set the used IRA algorithm
1396 Name(ira_algorithm) Type(enum ira_algorithm) UnknownError(unknown IRA algorithm %qs)
1399 Enum(ira_algorithm) String(CB) Value(IRA_ALGORITHM_CB)
1402 Enum(ira_algorithm) String(priority) Value(IRA_ALGORITHM_PRIORITY)
1405 Common Joined RejectNegative Enum(ira_region) Var(flag_ira_region) Init(IRA_REGION_MIXED)
1406 -fira-region=[one|all|mixed] Set regions for IRA
1409 Name(ira_region) Type(enum ira_region) UnknownError(unknown IRA region %qs)
1412 Enum(ira_region) String(one) Value(IRA_REGION_ONE)
1415 Enum(ira_region) String(all) Value(IRA_REGION_ALL)
1418 Enum(ira_region) String(mixed) Value(IRA_REGION_MIXED)
1421 Common Report Var(flag_ira_loop_pressure)
1422 Use IRA based register pressure calculation
1423 in RTL loop optimizations.
1425 fira-share-save-slots
1426 Common Report Var(flag_ira_share_save_slots) Init(1)
1427 Share slots for saving different hard registers.
1429 fira-share-spill-slots
1430 Common Report Var(flag_ira_share_spill_slots) Init(1)
1431 Share stack slots for spilled pseudo-registers.
1434 Common RejectNegative Joined UInteger Var(flag_ira_verbose) Init(5)
1435 -fira-verbose=<number> Control IRA's level of diagnostic messages.
1438 Common Report Var(flag_ivopts) Init(1) Optimization
1439 Optimize induction variables on trees
1442 Common Var(flag_jump_tables) Init(1) Optimization
1443 Use jump tables for sufficiently large switch statements
1445 fkeep-inline-functions
1446 Common Report Var(flag_keep_inline_functions)
1447 Generate code for functions even if they are fully inlined
1450 Common Report Var(flag_keep_static_consts) Init(1)
1451 Emit static const variables even if they are not used
1454 Common Report Var(flag_leading_underscore) Init(-1)
1455 Give external symbols a leading underscore
1459 Does nothing. Preserved for backward compatibility.
1463 Enable link-time optimization.
1466 Common RejectNegative Joined Var(flag_lto)
1467 Link-time optimization with number of parallel jobs or jobserver.
1470 Common Var(flag_lto_partition_1to1)
1471 Partition functions and vars at linktime based on object files they originate from
1473 flto-partition=balanced
1474 Common Var(flag_lto_partition_balanced)
1475 Partition functions and vars at linktime into approximately same sized buckets
1478 Common Var(flag_lto_partition_none)
1479 Disable partioning and streaming
1481 ; The initial value of -1 comes from Z_DEFAULT_COMPRESSION in zlib.h.
1482 flto-compression-level=
1483 Common Joined RejectNegative UInteger Var(flag_lto_compression_level) Init(-1)
1484 -flto-compression-level=<number> Use zlib compression level <number> for IL
1487 Common Report Var(flag_lto_report) Init(0) Optimization
1488 Report various link-time optimization statistics
1491 Common Report Var(flag_errno_math) Init(1) Optimization SetByCombined
1492 Set errno after built-in math functions
1495 Common Joined RejectNegative UInteger Var(flag_max_errors)
1496 -fmax-errors=<number> Maximum number of errors to report
1499 Common Report Var(mem_report)
1500 Report on permanent memory allocation
1502 ; This will attempt to merge constant section constants, if 1 only
1503 ; string constants and constants from constant pool, if 2 also constant
1505 fmerge-all-constants
1506 Common Report Var(flag_merge_constants,2) Init(1) Optimization
1507 Attempt to merge identical constants and constant variables
1510 Common Report Var(flag_merge_constants,1) Optimization
1511 Attempt to merge identical constants across compilation units
1513 fmerge-debug-strings
1514 Common Report Var(flag_merge_debug_strings) Init(1)
1515 Attempt to merge identical debug strings across compilation units
1518 Common RejectNegative Joined UInteger
1519 -fmessage-length=<number> Limit diagnostics to <number> characters per line. 0 suppresses line-wrapping
1522 Common Report Var(flag_modulo_sched) Optimization
1523 Perform SMS based modulo scheduling before the first scheduling pass
1525 fmodulo-sched-allow-regmoves
1526 Common Report Var(flag_modulo_sched_allow_regmoves)
1527 Perform SMS based modulo scheduling with register moves allowed
1529 fmove-loop-invariants
1530 Common Report Var(flag_move_loop_invariants) Init(1) Optimization
1531 Move loop invariant computations out of loops
1534 Common RejectNegative Report Var(flag_mudflap)
1535 Add mudflap bounds-checking instrumentation for single-threaded program
1538 Common RejectNegative Report Var(flag_mudflap,2)
1539 Add mudflap bounds-checking instrumentation for multi-threaded program
1542 Common RejectNegative Report Var(flag_mudflap_ignore_reads)
1543 Ignore read operations when inserting mudflap instrumentation
1546 Common RejectNegative Report Var(flag_tsan)
1547 Add ThreadSanitizer instrumentation
1550 Common RejectNegative Joined Var(flag_tsan_ignore)
1551 -ftsan-ignore=filename ThreadSanitizer ignore file
1554 Common Var(flag_dce) Init(1) Optimization
1555 Use the RTL dead code elimination pass
1558 Common Var(flag_dse) Init(1) Optimization
1559 Use the RTL dead store elimination pass
1561 freschedule-modulo-scheduled-loops
1562 Common Report Var(flag_resched_modulo_sched) Optimization
1563 Enable/Disable the traditional scheduling in loops that already passed modulo scheduling
1565 fnon-call-exceptions
1566 Common Report Var(flag_non_call_exceptions) Optimization
1567 Support synchronous non-call exceptions
1570 Common Report Var(flag_omit_frame_pointer) Optimization
1571 When possible do not generate stack frames
1574 Common Report Var(flag_opt_info) Optimization Init(0)
1575 Enable verbose informational messages for optimizations (same as -fopt-info=1)
1577 ; fopt-info=0: no message will be emitted.
1578 ; fopt-info or fopt-info=1: emit important warnings and optimization messages with
1579 ; large performance impact.
1580 ; fopt-info=2: warnings and optimization messages targeting power users.
1581 ; fopt-info=3: informational messages for compiler developers.
1583 Common RejectNegative Joined UInteger Optimization
1584 -fopt-info=[0|1|2|3] Set the verbose level of informational messages for optimizations
1586 foptimize-register-move
1587 Common Report Var(flag_regmove) Optimization
1588 Do the full register move optimization pass
1590 foptimize-sibling-calls
1591 Common Report Var(flag_optimize_sibling_calls) Optimization
1592 Optimize sibling and tail recursive calls
1595 Common Report Var(flag_partial_inlining)
1596 Perform partial inlining
1599 Common Report Var(pre_ipa_mem_report)
1600 Report on memory allocation before interprocedural optimization
1602 fpost-ipa-mem-report
1603 Common Report Var(post_ipa_mem_report)
1604 Report on memory allocation before interprocedural optimization
1607 Common Report Var(flag_pack_struct) Optimization
1608 Pack structure members together without holes
1611 Common RejectNegative Joined UInteger Optimization
1612 -fpack-struct=<number> Set initial maximum structure member alignment
1615 Common Report Var(flag_pcc_struct_return,1) Init(DEFAULT_PCC_STRUCT_RETURN)
1616 Return small aggregates in memory, not registers
1619 Common Report Var(flag_peel_loops) Optimization
1620 Perform loop peeling
1623 Common Report Var(flag_no_peephole,0) Optimization
1624 Enable machine specific peephole optimizations
1627 Common Report Var(flag_peephole2) Optimization
1628 Enable an RTL peephole pass before sched2
1631 Common Report Var(flag_pic,2)
1632 Generate position-independent code if possible (large mode)
1635 Common Report Var(flag_pie,2)
1636 Generate position-independent code for executables if possible (large mode)
1639 Common Report Var(flag_pic,1)
1640 Generate position-independent code if possible (small mode)
1643 Common Report Var(flag_pie,1)
1644 Generate position-independent code for executables if possible (small mode)
1647 Common Joined RejectNegative Var(common_deferred_options) Defer
1648 Specify a plugin to load
1651 Common Joined RejectNegative Var(common_deferred_options) Defer
1652 -fplugin-arg-<name>-<key>[=<value>] Specify argument <key>=<value> for plugin <name>
1654 fpmu-profile-generate=
1655 Common Joined RejectNegative Var(flag_pmu_profile_generate)
1656 -fpmu-profile-generate=[load-latency] Generate pmu profile for cache misses. Currently only pfmon based load latency profiling is supported on Intel/PEBS and AMD/IBS platforms.
1659 Common Joined RejectNegative Var(flag_pmu_profile_use)
1660 -fpmu-profile-use=[load-latency] Use pmu profile data while optimizing. Currently only perfmon based load latency profiling is supported on Intel/PEBS and AMD/IBS platforms.
1662 fpredictive-commoning
1663 Common Report Var(flag_predictive_commoning) Optimization
1664 Run predictive commoning optimization.
1666 fprefetch-loop-arrays
1667 Common Report Var(flag_prefetch_loop_arrays) Init(-1) Optimization
1668 Generate prefetch instructions, if available, for arrays in loops
1671 Common Report Var(profile_flag)
1672 Enable basic program profiling code
1675 Common Report Var(profile_arc_flag)
1676 Insert arc-based program profiling code
1679 Common Joined RejectNegative Var(profile_data_prefix)
1680 Set the top-level directory for storing the profile data.
1681 The default is 'pwd'.
1684 Common Report Var(flag_profile_correction)
1685 Enable correction of flow inconsistent profile data input
1688 Common Report Var(flag_profile_dump) Init(0) Optimization
1689 Dump CFG profile for comparison.
1693 Enable common options for generating profile info for profile feedback directed optimizations
1696 Common Joined RejectNegative
1697 Enable common options for generating profile info for profile feedback directed optimizations, and set -fprofile-dir=
1699 fprofile-generate-sampling
1700 Common Var(flag_profile_generate_sampling)
1701 Turn on instrumentation sampling with -fprofile-generate with rate set by --param profile-generate-sampling-rate or environment variable GCOV_SAMPLING_RATE
1704 Common Var(flag_profile_use)
1705 Enable common options for performing profile feedback directed optimizations
1708 Common Joined RejectNegative
1709 Enable common options for performing profile feedback directed optimizations, and set -fprofile-dir=
1712 Common Report Var(flag_profile_values)
1713 Insert code to profile values of expressions
1716 Common Var(common_deferred_options) Defer
1719 Common Joined RejectNegative Var(common_deferred_options) Defer
1720 -frandom-seed=<string> Make compile reproducible using <string>
1722 ; This switch causes the command line that was used to create an
1723 ; object file to be recorded into the object file. The exact format
1724 ; of this recording is target and binary file format dependent.
1725 ; It is related to the -fverbose-asm switch, but that switch only
1726 ; records information in the assembler output file as comments, so
1727 ; they never reach the object file.
1728 frecord-gcc-switches
1729 Common Report Var(flag_record_gcc_switches)
1730 Record gcc command line switches in the object file.
1732 ; This option differs from frecord-gcc-switches in the way that it
1733 ; divide the command line options into several categories. And the
1734 ; section is not mergable so that linker can save gcc switches for
1736 frecord-gcc-switches-in-elf
1737 Common Report Var(flag_record_gcc_switches_in_elf)
1738 Record the compiler optimizations in a .gnu.switches.text section.
1741 Common Report Var(flag_pcc_struct_return,0) Optimization
1742 Return small aggregates in registers
1745 Common Report Var(flag_regmove) Optimization
1746 Enables a register move optimization
1749 Common Report Var(flag_rename_registers) Init(2) Optimization
1750 Perform a register renaming optimization pass
1753 Common Report Var(flag_reorder_blocks) Optimization
1754 Reorder basic blocks to improve code placement
1756 freorder-blocks-and-partition
1757 Common Report Var(flag_reorder_blocks_and_partition) Optimization
1758 Reorder basic blocks and partition into hot and cold sections
1761 Common Report Var(flag_reorder_functions) Optimization
1762 Reorder functions to improve code placement
1764 frerun-cse-after-loop
1765 Common Report Var(flag_rerun_cse_after_loop) Optimization
1766 Add a common subexpression elimination pass after loop optimizations
1770 Does nothing. Preserved for backward compatibility.
1773 Common Report Var(flag_rounding_math) Optimization SetByCombined
1774 Disable optimizations that assume default FP rounding behavior
1777 Common Report Var(flag_schedule_interblock) Init(1) Optimization
1778 Enable scheduling across basic blocks
1781 Common Report Var(flag_sched_pressure) Init(0) Optimization
1782 Enable register pressure sensitive insn scheduling
1785 Common Report Var(flag_schedule_speculative) Init(1) Optimization
1786 Allow speculative motion of non-loads
1789 Common Report Var(flag_schedule_speculative_load) Optimization
1790 Allow speculative motion of some loads
1792 fsched-spec-load-dangerous
1793 Common Report Var(flag_schedule_speculative_load_dangerous) Optimization
1794 Allow speculative motion of more loads
1797 Common RejectNegative Joined UInteger Var(sched_verbose_param)
1798 -fsched-verbose=<number> Set the verbosity level of the scheduler
1800 fsched2-use-superblocks
1801 Common Report Var(flag_sched2_use_superblocks) Optimization
1802 If scheduling post reload, do superblock scheduling
1806 Does nothing. Preserved for backward compatibility.
1809 Common Report Var(flag_schedule_insns) Optimization
1810 Reschedule instructions before register allocation
1813 Common Report Var(flag_schedule_insns_after_reload) Optimization
1814 Reschedule instructions after register allocation
1816 ; This flag should be on when a target implements non-trivial
1817 ; scheduling hooks, maybe saving some information for its own sake.
1818 ; On IA64, for example, this is used for correct bundling.
1819 fselective-scheduling
1820 Common Report Var(flag_selective_scheduling) Optimization
1821 Schedule instructions using selective scheduling algorithm
1823 fselective-scheduling2
1824 Common Report Var(flag_selective_scheduling2) Optimization
1825 Run selective scheduling after reload
1827 fsel-sched-pipelining
1828 Common Report Var(flag_sel_sched_pipelining) Init(0) Optimization
1829 Perform software pipelining of inner loops during selective scheduling
1831 fsel-sched-pipelining-outer-loops
1832 Common Report Var(flag_sel_sched_pipelining_outer_loops) Init(0) Optimization
1833 Perform software pipelining of outer loops during selective scheduling
1835 fsel-sched-reschedule-pipelined
1836 Common Report Var(flag_sel_sched_reschedule_pipelined) Init(0) Optimization
1837 Reschedule pipelined regions without pipelining
1839 ; sched_stalled_insns means that insns can be moved prematurely from the queue
1840 ; of stalled insns into the ready list.
1841 fsched-stalled-insns
1842 Common Report Var(flag_sched_stalled_insns) Optimization UInteger
1843 Allow premature scheduling of queued insns
1845 fsched-stalled-insns=
1846 Common RejectNegative Joined UInteger
1847 -fsched-stalled-insns=<number> Set number of queued insns that can be prematurely scheduled
1849 ; sched_stalled_insns_dep controls how many recently scheduled cycles will
1850 ; be examined for a dependency on a stalled insn that is candidate for
1851 ; premature removal from the queue of stalled insns into the ready list (has
1852 ; an effect only if the flag 'sched_stalled_insns' is set).
1853 fsched-stalled-insns-dep
1854 Common Report Var(flag_sched_stalled_insns_dep,1) Init(1) Optimization UInteger
1855 Set dependence distance checking in premature scheduling of queued insns
1857 fsched-stalled-insns-dep=
1858 Common RejectNegative Joined UInteger
1859 -fsched-stalled-insns-dep=<number> Set dependence distance checking in premature scheduling of queued insns
1861 fsched-group-heuristic
1862 Common Report Var(flag_sched_group_heuristic) Init(1) Optimization
1863 Enable the group heuristic in the scheduler
1865 fsched-critical-path-heuristic
1866 Common Report Var(flag_sched_critical_path_heuristic) Init(1) Optimization
1867 Enable the critical path heuristic in the scheduler
1869 fsched-spec-insn-heuristic
1870 Common Report Var(flag_sched_spec_insn_heuristic) Init(1) Optimization
1871 Enable the speculative instruction heuristic in the scheduler
1873 fsched-rank-heuristic
1874 Common Report Var(flag_sched_rank_heuristic) Init(1) Optimization
1875 Enable the rank heuristic in the scheduler
1877 fsched-last-insn-heuristic
1878 Common Report Var(flag_sched_last_insn_heuristic) Init(1) Optimization
1879 Enable the last instruction heuristic in the scheduler
1881 fsched-dep-count-heuristic
1882 Common Report Var(flag_sched_dep_count_heuristic) Init(1) Optimization
1883 Enable the dependent count heuristic in the scheduler
1886 Common Report Var(flag_section_anchors) Optimization
1887 Access data in the same section from shared anchor points
1891 Does nothing. Preserved for backward compatibility.
1894 Common Report Var(flag_zee) Init(0)
1895 Eliminate redundant zero extensions on targets that support implicit extensions.
1898 Common Report Var(flag_show_column) Init(1)
1899 Show column numbers in diagnostics, when available. Default on
1902 Common Report Var(flag_signaling_nans) Optimization SetByCombined
1903 Disable optimizations observable by IEEE signaling NaNs
1906 Common Report Var(flag_signed_zeros) Init(1) Optimization SetByCombined
1907 Disable floating point optimizations that ignore the IEEE signedness of zero
1909 fsingle-precision-constant
1910 Common Report Var(flag_single_precision_constant) Optimization
1911 Convert floating point constants to single precision constants
1914 Common Report Var(flag_sized_delete) Optimization
1915 Support delete operator with objetc's size as the second parameter.
1917 fsplit-ivs-in-unroller
1918 Common Report Var(flag_split_ivs_in_unroller) Init(1) Optimization
1919 Split lifetimes of induction variables when loops are unrolled
1922 Common Report Var(flag_split_stack) Init(-1)
1923 Generate discontiguous stack frames
1926 Common Report Var(flag_split_wide_types) Optimization
1927 Split wide types into independent registers
1929 fvariable-expansion-in-unroller
1930 Common Report Var(flag_variable_expansion_in_unroller) Optimization
1931 Apply variable expansion when loops are unrolled
1934 Common Report RejectNegative Joined
1935 -fstack-check=[no|generic|specific] Insert stack checking code into the program
1938 Common Alias(fstack-check=, specific, no)
1939 Insert stack checking code into the program. Same as -fstack-check=specific
1942 Common Var(common_deferred_options) Defer
1944 fstack-limit-register=
1945 Common RejectNegative Joined Var(common_deferred_options) Defer
1946 -fstack-limit-register=<register> Trap if the stack goes past <register>
1948 fstack-limit-symbol=
1949 Common RejectNegative Joined Var(common_deferred_options) Defer
1950 -fstack-limit-symbol=<name> Trap if the stack goes past symbol <name>
1953 Common Report Var(flag_stack_protect, 1)
1954 Use propolice as a stack protection method
1956 fstack-protector-strong
1957 Common Report RejectNegative Var(flag_stack_protect, 2)
1958 Use a smart stack protection method for certain functions
1960 fstack-protector-all
1961 Common Report RejectNegative Var(flag_stack_protect, 3)
1962 Use a stack protection method for every function
1965 Common RejectNegative Var(flag_stack_usage)
1966 Output stack usage information on a per-function basis
1970 Does nothing. Preserved for backward compatibility.
1972 ; Nonzero if we should do (language-dependent) alias analysis.
1973 ; Typically, this analysis will assume that expressions of certain
1974 ; types do not alias expressions of certain other types. Only used
1975 ; if alias analysis (in general) is enabled.
1977 Common Report Var(flag_strict_aliasing) Optimization
1978 Assume strict aliasing rules apply
1981 Common Report Var(flag_strict_overflow)
1982 Treat signed overflow as undefined
1985 Common Report Var(flag_syntax_only)
1986 Check for syntax errors, then stop
1989 Common Report Var(flag_test_coverage)
1990 Create data files needed by \"gcov\"
1993 Common Report Var(flag_thread_jumps) Optimization
1994 Perform jump threading optimizations
1997 Common Report Var(time_report)
1998 Report the time taken by each compiler pass
2001 Common Joined RejectNegative Enum(tls_model) Var(flag_tls_default) Init(TLS_MODEL_GLOBAL_DYNAMIC)
2002 -ftls-model=[global-dynamic|local-dynamic|initial-exec|local-exec] Set the default thread-local storage code generation model
2005 Name(tls_model) Type(enum tls_model) UnknownError(unknown TLS model %qs)
2008 Enum(tls_model) String(global-dynamic) Value(TLS_MODEL_GLOBAL_DYNAMIC)
2011 Enum(tls_model) String(local-dynamic) Value(TLS_MODEL_LOCAL_DYNAMIC)
2014 Enum(tls_model) String(initial-exec) Value(TLS_MODEL_INITIAL_EXEC)
2017 Enum(tls_model) String(local-exec) Value(TLS_MODEL_LOCAL_EXEC)
2020 Common Report Var(flag_toplevel_reorder) Init(2) Optimization
2021 Reorder top level functions, variables, and asms
2024 Common Report Var(flag_tracer)
2025 Perform superblock formation via tail duplication
2027 ; Zero means that floating-point math operations cannot generate a
2028 ; (user-visible) trap. This is the case, for example, in nonstop
2029 ; IEEE 754 arithmetic.
2031 Common Report Var(flag_trapping_math) Init(1) Optimization SetByCombined
2032 Assume floating-point operations can trap
2035 Common Report Var(flag_trapv) Optimization
2036 Trap for signed overflow in addition, subtraction and multiplication
2039 Common Report Var(flag_tree_ccp) Optimization
2040 Enable SSA-CCP optimization on trees
2043 Common Report Var(flag_tree_bit_ccp) Optimization
2044 Enable SSA-BIT-CCP optimization on trees
2048 Does nothing. Preserved for backward compatibility.
2051 Common Report Var(flag_tree_ch) Optimization
2052 Enable loop header copying on trees
2055 Common Report Var(flag_tree_copyrename) Optimization
2056 Replace SSA temporaries with better names in copies
2059 Common Report Var(flag_tree_copy_prop) Optimization
2060 Enable copy propagation on trees
2062 ftree-store-copy-prop
2064 Does nothing. Preserved for backward compatibility.
2067 Common Report Var(flag_tree_cselim) Init(2) Optimization
2068 Transform condition stores into unconditional ones
2070 ftree-switch-conversion
2071 Common Report Var(flag_tree_switch_conversion) Optimization
2072 Perform conversions of switch initializations.
2075 Common Report Var(flag_tree_dce) Optimization
2076 Enable SSA dead code elimination optimization on trees
2078 ftree-dominator-opts
2079 Common Report Var(flag_tree_dom) Optimization
2080 Enable dominator optimizations
2083 Common Report Var(flag_tree_dse) Optimization
2084 Enable dead store elimination
2087 Common Report Var(flag_tree_forwprop) Init(1) Optimization
2088 Enable forward propagation on trees
2091 Common Report Var(flag_tree_fre) Optimization
2092 Enable Full Redundancy Elimination (FRE) on trees
2094 ftree-loop-distribution
2095 Common Report Var(flag_tree_loop_distribution) Optimization
2096 Enable loop distribution on trees
2098 ftree-loop-distribute-patterns
2099 Common Report Var(flag_tree_loop_distribute_patterns) Optimization
2100 Enable loop distribution for patterns transformed into a library call
2103 Common Report Var(flag_tree_loop_im) Init(1) Optimization
2104 Enable loop invariant motion on trees
2107 Common Alias(floop-interchange)
2108 Enable loop interchange transforms. Same as -floop-interchange
2111 Common Report Var(flag_tree_loop_ivcanon) Init(1) Optimization
2112 Create canonical induction variables in loops
2115 Common Report Var(flag_tree_loop_optimize) Init(1) Optimization
2116 Enable loop optimizations on tree level
2118 ftree-parallelize-loops=
2119 Common Report Joined RejectNegative UInteger Var(flag_tree_parallelize_loops) Init(1)
2120 Enable automatic parallelization of loops
2123 Common Report Var(flag_tree_phiprop) Init(1) Optimization
2124 Enable hoisting loads from conditional pointers.
2127 Common Report Var(flag_tree_pre) Optimization
2128 Enable SSA-PRE optimization on trees
2131 Common Report Var(flag_tree_pta) Init(1) Optimization
2132 Perform function-local points-to analysis on trees.
2135 Common Report Var(flag_tree_reassoc) Init(1) Optimization
2136 Enable reassociation on tree level
2140 Does nothing. Preserved for backward compatibility.
2143 Common Report Var(flag_tree_sink) Optimization
2144 Enable SSA code sinking on trees
2147 Common Report Var(flag_tree_sra) Optimization
2148 Perform scalar replacement of aggregates
2151 Common Report Var(flag_tree_ter) Optimization
2152 Replace temporary expressions in the SSA->normal pass
2155 Common Report Var(flag_tree_live_range_split) Optimization
2156 Perform live range splitting during the SSA->normal pass
2159 Common Report Var(flag_tree_vrp) Init(0) Optimization
2160 Perform Value Range Propagation on trees
2162 fstrict-enum-precision
2163 Common Report Var(flag_strict_enum_precision) Init(1) Optimization
2164 Perform transformations based on enum precision
2167 Common Report Var(flag_unit_at_a_time) Init(1) Optimization
2168 Compile whole compilation unit at a time
2171 Common Report Var(flag_unroll_loops) Optimization
2172 Perform loop unrolling when iteration count is known
2175 Common Report Var(flag_unroll_all_loops) Optimization
2176 Perform loop unrolling for all loops
2178 ; Nonzero means that loop optimizer may assume that the induction variables
2179 ; that control loops do not overflow and that the loops with nontrivial
2180 ; exit condition are not infinite
2181 funsafe-loop-optimizations
2182 Common Report Var(flag_unsafe_loop_optimizations) Optimization
2183 Allow loop optimizations to assume that the loops behave in normal way
2186 Common Report Var(flag_associative_math) SetByCombined
2187 Allow optimization for floating-point arithmetic which may change the
2188 result of the operation due to rounding.
2191 Common Report Var(flag_reciprocal_math) SetByCombined
2192 Same as -fassociative-math for expressions which include division.
2194 ; Nonzero means that unsafe floating-point math optimizations are allowed
2195 ; for the sake of speed. IEEE compliance is not guaranteed, and operations
2196 ; are allowed to assume that their arguments and results are "normal"
2197 ; (e.g., nonnegative for SQRT).
2198 funsafe-math-optimizations
2199 Common Report Var(flag_unsafe_math_optimizations) Optimization SetByCombined
2200 Allow math optimizations that may violate IEEE or ISO standards
2203 Common Report Var(flag_unswitch_loops) Optimization
2204 Perform loop unswitching
2207 Common Report Var(flag_unwind_tables) Optimization
2208 Just generate unwind tables for exception handling
2211 Common Joined Undocumented
2216 ; Positive if we should track variables, negative if we should run
2217 ; the var-tracking pass only to discard debug annotations, zero if
2218 ; we're not to run it. When flag_var_tracking == 2 (AUTODETECT_VALUE) it
2219 ; will be set according to optimize, debug_info_level and debug_hooks
2220 ; in process_options ().
2222 Common Report Var(flag_var_tracking) Init(2) Optimization
2223 Perform variable tracking
2225 ; Positive if we should track variables at assignments, negative if
2226 ; we should run the var-tracking pass only to discard debug
2227 ; annotations. When flag_var_tracking_assignments ==
2228 ; AUTODETECT_VALUE it will be set according to flag_var_tracking.
2229 fvar-tracking-assignments
2230 Common Report Var(flag_var_tracking_assignments) Init(2) Optimization
2231 Perform variable tracking by annotating assignments
2233 ; Nonzero if we should toggle flag_var_tracking_assignments after
2234 ; processing options and computing its default. */
2235 fvar-tracking-assignments-toggle
2236 Common Report Var(flag_var_tracking_assignments_toggle) Optimization
2237 Toggle -fvar-tracking-assignments
2239 fvar-tracking-uninit
2240 Common Report Var(flag_var_tracking_uninit) Optimization
2241 Perform variable tracking and also tag variables that are uninitialized
2244 Common Report Var(flag_tree_vectorize) Optimization
2245 Enable loop vectorization on trees
2248 Common Report Var(flag_tree_slp_vectorize) Init(2) Optimization
2249 Enable basic block vectorization (SLP) on trees
2252 Common Report Var(flag_vect_cost_model) Optimization
2253 Enable use of cost model in vectorization
2255 ftree-vect-loop-version
2256 Common Report Var(flag_tree_vect_loop_version) Init(1) Optimization
2257 Enable loop versioning when doing loop vectorization on trees
2259 ftree-vectorizer-verbose=
2260 Common RejectNegative Joined UInteger
2261 -ftree-vectorizer-verbose=<number> Set the verbosity level of the vectorizer
2264 Common Report Var(flag_tree_scev_cprop) Init(1) Optimization
2265 Enable copy propagation of scalar-evolution information.
2267 ; -fverbose-asm causes extra commentary information to be produced in
2268 ; the generated assembly code (to make it more readable). This option
2269 ; is generally only of use to those who actually need to read the
2270 ; generated assembly code (perhaps while debugging the compiler itself).
2271 ; -fno-verbose-asm, the default, causes the extra information
2272 ; to not be added and is useful when comparing two assembler files.
2274 Common Report Var(flag_verbose_asm)
2275 Add extra commentary to assembler output
2278 Common Joined RejectNegative Enum(symbol_visibility) Var(default_visibility) Init(VISIBILITY_DEFAULT)
2279 -fvisibility=[default|internal|hidden|protected] Set the default symbol visibility
2282 Name(symbol_visibility) Type(enum symbol_visibility) UnknownError(unrecognized visibility value %qs)
2285 Enum(symbol_visibility) String(default) Value(VISIBILITY_DEFAULT)
2288 Enum(symbol_visibility) String(internal) Value(VISIBILITY_INTERNAL)
2291 Enum(symbol_visibility) String(hidden) Value(VISIBILITY_HIDDEN)
2294 Enum(symbol_visibility) String(protected) Value(VISIBILITY_PROTECTED)
2297 Common Report Var(flag_value_profile_transformations) Optimization
2298 Use expression value profiles in optimizations
2301 Common Report Var(flag_web) Init(2) Optimization
2302 Construct webs and split unrelated uses of single variable
2304 ftree-builtin-call-dce
2305 Common Report Var(flag_tree_builtin_call_dce) Init(0) Optimization
2306 Enable conditional dead code elimination for builtin calls
2308 fclone-hot-version-paths
2309 Common Report Var(flag_clone_hot_version_paths) Init(0)
2310 Enable cloning and hoisting of hot multiversioned paths
2313 Common Report Var(flag_whole_program) Init(0) Optimization
2314 Perform whole program optimizations
2317 Common Report Var(flag_wrapv) Optimization
2318 Assume signed arithmetic overflow wraps around
2320 fzero-initialized-in-bss
2321 Common Report Var(flag_zero_initialized_in_bss) Init(1)
2322 Put zero initialized data in the bss section
2325 Common JoinedOrMissing
2326 Generate debug information in default format
2329 Common JoinedOrMissing Negative(gdwarf-)
2330 Generate debug information in COFF format
2333 Common Joined UInteger Var(dwarf_version) Init(2) Negative(gstabs)
2334 Generate debug information in DWARF v2 (or later) format
2337 Common Driver JoinedOrMissing Var(dwarf_split_debug_info,1)
2338 Generate debug information in separate .dwo files
2341 Common JoinedOrMissing
2342 Generate debug information in default extended format
2345 Common RejectNegative
2346 Generate debug information at level 1 with minimal line table
2349 Common JoinedOrMissing Negative(gstabs+)
2350 Generate debug information in STABS format
2353 Common JoinedOrMissing Negative(gvms)
2354 Generate debug information in extended STABS format
2357 Common RejectNegative Var(dwarf_strict,0) Init(-1)
2358 Emit DWARF additions beyond selected version
2361 Common Report RejectNegative Var(dwarf_strict,1)
2362 Don't emit DWARF additions beyond selected version
2365 Common Report Var(flag_gtoggle)
2366 Toggle debug information generation
2369 Common JoinedOrMissing Negative(gxcoff)
2370 Generate debug information in VMS format
2373 Common JoinedOrMissing Negative(gxcoff+)
2374 Generate debug information in XCOFF format
2377 Common JoinedOrMissing Negative(gcoff)
2378 Generate debug information in extended XCOFF format
2381 Driver Joined Separate
2384 Common Joined Var(plugindir_string) Init(0)
2385 -iplugindir=<dir> Set <dir> to be the default plugin directory
2388 Driver Joined Separate
2393 no-canonical-prefixes
2409 Common Driver Joined Separate Var(asm_file_name) MissingArgError(missing filename after %qs)
2410 -o <file> Place output into <file>
2413 Common Var(profile_flag)
2414 Enable function profiling
2417 Driver Var(pass_exit_codes)
2420 Common Var(pedantic)
2421 Issue warnings needed for strict compliance to the standard
2424 Common Var(flag_pedantic_errors)
2425 Like -pedantic but issue them as errors
2431 Driver Var(use_pipes)
2434 Driver JoinedOrMissing Var(print_file_name)
2436 print-libgcc-file-name
2439 print-multi-directory
2440 Driver Var(print_multi_directory)
2443 Driver Var(print_multi_lib)
2445 print-multi-os-directory
2446 Driver Var(print_multi_os_directory)
2449 Driver JoinedOrMissing Var(print_prog_name)
2452 Driver Var(print_search_dirs)
2455 Driver Var(print_sysroot)
2457 print-sysroot-headers-suffix
2458 Driver Var(print_sysroot_headers_suffix)
2461 Common Var(quiet_flag) RejectDriver
2462 Do not display functions compiled or elapsed time
2480 Driver Var(report_times)
2483 Driver JoinedOrMissing
2486 Driver Joined Separate
2490 ; C option, but driver must not handle as "-u ndef".
2493 Common Driver Var(verbose_flag)
2494 Enable verbose output
2497 Common Var(version_flag) RejectDriver
2498 Display the compiler's version
2501 Common Var(inhibit_warnings)
2505 Driver Separate Var(wrapper_string)
2508 Driver Joined Separate
2511 Common RejectNegative Negative(pie)
2512 Create a shared library
2518 Driver Separate Alias(specs=)
2531 ; Documented for Fortran, but always accepted by driver.
2538 ; Documented for Go, but always accepted by driver.
2544 Common RejectNegative Negative(shared)
2545 Create a position independent executable
2548 Driver Joined Separate
2550 ; This comment is to ensure we retain the blank line above.