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 ; Nonzero means use GNU-only extensions in the generated symbolic
124 ; debugging information. Currently, this only has an effect when
125 ; write_symbols is set to DBX_DEBUG, XCOFF_DEBUG, or DWARF_DEBUG.
127 bool use_gnu_debug_info_extensions
129 ; Original value of maximum field alignment in bytes, specified via
130 ; -fpack-struct=<value>.
132 unsigned int initial_max_fld_align = TARGET_DEFAULT_PACK_STRUCT
135 enum vect_verbosity_levels user_vect_verbosity_level = MAX_VERBOSITY_LEVEL
137 ; Type of stack check.
139 enum stack_check_type flag_stack_check = NO_STACK_CHECK
141 ; True if stack usage information needs to be computed.
143 bool flag_stack_usage_info = false
145 ; -dA causes debug commentary information to be produced in
146 ; the generated assembly code (to make it more readable). This option
147 ; is generally only of use to those who actually need to read the
148 ; generated assembly code (perhaps while debugging the compiler itself).
149 ; Currently, this switch is only used by dwarf2out.c; however, it is intended
150 ; to be a catchall for printing debug information in the assembler file.
154 ; -dP causes the rtl to be emitted as a comment in assembly.
156 int flag_dump_rtl_in_asm
158 ; Whether -da was passed (used only in handle_common_deferred_options).
160 bool flag_dump_all_passed
162 ; Other flags saying which kinds of debugging dump have been requested.
165 int rtl_dump_and_exit
168 int flag_print_asm_name
171 enum graph_dump_types graph_dump_format = no_graph
173 ; Name of top-level original source file (what was input to cpp).
174 ; This comes from the #-command at the beginning of the actual input.
175 ; If there isn't any there, then this is the cc1 input file name.
177 const char *main_input_filename
179 ; Pointer to base name in main_input_filename, with directories and a
180 ; single final extension removed, and the length of this base
184 const char *main_input_basename
187 int main_input_baselength
189 ; Which options have been printed by --help.
193 ; Which enums have been printed by --help. 0 = not printed, no
194 ; relevant options seen, 1 = relevant option seen, not yet printed, 2
197 char *help_enum_printed
199 ; The number of columns for --help output.
201 unsigned int help_columns
203 ; Whether this options structure has been through finish_options
205 bool flag_opts_finished
217 Driver Alias(coverage)
223 Common Separate Alias(d)
226 Common Joined Alias(d)
229 Common Separate Alias(dumpbase)
232 Common Separate Alias(dumpdir)
235 Driver Separate Alias(e)
238 Driver Joined Alias(e)
241 Common Warning Alias(Wextra)
244 Driver Separate Alias(Xassembler)
247 Driver JoinedOrMissing Alias(Xassembler)
250 Driver Separate Alias(Xlinker)
253 Driver JoinedOrMissing Alias(Xlinker)
256 Driver Separate Alias(u)
259 Driver Joined Alias(u)
262 Common Driver Var(help_flag)
263 Display this information
266 Common Driver Report Joined
267 --help=<class> Display descriptions of a specific class of options. <class> is one or more of optimizers, target, warnings, undocumented, params
270 Driver Separate Alias(x)
273 Driver Joined Alias(x)
276 Driver Separate Alias(L)
279 Driver Joined Alias(L)
281 -no-canonical-prefixes
282 Driver Alias(no-canonical-prefixes)
285 Driver Alias(canonical-prefixes)
287 -no-standard-libraries
288 Driver Alias(nostdlib)
297 Common Driver Separate Alias(o) MissingArgError(missing filename after %qs)
300 Common Driver Joined Alias(o) MissingArgError(missing filename after %qs)
303 Driver Alias(pass-exit-codes)
306 Common Alias(pedantic)
309 Common Alias(pedantic-errors)
318 Driver Separate Alias(B)
321 Driver JoinedOrMissing Alias(B)
327 Driver Separate Alias(print-file-name=)
330 Driver JoinedOrMissing Alias(print-file-name=)
332 -print-libgcc-file-name
333 Driver Alias(print-libgcc-file-name)
335 -print-multi-directory
336 Driver Alias(print-multi-directory)
339 Driver Alias(print-multi-lib)
341 -print-multi-os-directory
342 Driver Alias(print-multi-os-directory)
345 Driver Separate Alias(print-prog-name=)
348 Driver JoinedOrMissing Alias(print-prog-name=)
351 Driver Alias(print-search-dirs)
354 Driver Alias(print-sysroot)
356 -print-sysroot-headers-suffix
357 Driver Alias(print-sysroot-headers-suffix)
363 Driver Alias(save-temps)
369 Driver Separate Alias(specs=)
372 Driver Joined Alias(specs=)
378 Driver Alias(symbolic)
382 Alias for --help=target
390 ;; The driver used to convert options such as --help into forms such
391 ;; as -fhelp; the following four entries are for compatibility with
392 ;; any direct uses of those (undocumented) -f forms
394 Common Driver Alias(-help)
397 Common Driver Joined Alias(-help=)
400 Common Driver Alias(-target-help)
403 Common Driver Alias(-version)
407 --param <param>=<value> Set parameter <param> to value. See below for a complete list of parameters
410 Common Joined Alias(-param)
413 Driver Separate Alias(-sysroot=)
416 Driver JoinedOrMissing
422 Driver Joined Separate
428 Driver Joined Separate
434 Common JoinedOrMissing Optimization
435 -O<number> Set optimization level to <number>
439 Optimize for space rather than speed
443 Optimize for speed disregarding exact standards compliance
455 Driver Joined Separate
461 Driver Joined Separate
482 Common RejectNegative Warning Alias(Wextra)
483 This switch is deprecated; use -Wextra instead
486 Driver JoinedOrMissing
489 Driver JoinedOrMissing
492 Driver JoinedOrMissing
495 Common Var(warn_aggregate_return) Warning
496 Warn about returning structures, unions or arrays
499 Common Var(warn_array_bounds) Warning
500 Warn if an array is accessed out of bounds
503 Common Var(warn_attributes) Init(1) Warning
504 Warn about inappropriate attribute usage
507 Common Var(warn_cast_align) Warning
508 Warn about pointer casts which increase alignment
511 Common Var(warn_cpp) Init(1) Warning
512 Warn when a #warning directive is encountered
514 Wdeprecated-declarations
515 Common Var(warn_deprecated_decl) Init(1) Warning
516 Warn about uses of __attribute__((deprecated)) declarations
518 Wdisabled-optimization
519 Common Var(warn_disabled_optimization) Warning
520 Warn when an optimization pass is disabled
523 Common Var(warnings_are_errors)
524 Treat all warnings as errors
528 Treat specified warning as error
531 Common Var(extra_warnings) Warning
532 Print extra (possibly unwanted) warnings
535 Common Var(flag_fatal_errors)
536 Exit on the first error occurred
539 Common RejectNegative Joined UInteger
540 -Wframe-larger-than=<number> Warn if a function's stack frame requires more than <number> bytes
543 Common Var(warn_inline) Warning
544 Warn when an inlined function cannot be inlined
547 Common RejectNegative Joined Warning Undocumented Alias(Wlarger-than=)
550 Common RejectNegative Joined UInteger Warning
551 -Wlarger-than=<number> Warn if an object is larger than <number> bytes
553 Wunsafe-loop-optimizations
554 Common Var(warn_unsafe_loop_optimizations) Warning
555 Warn if the loop cannot be optimized due to nontrivial assumptions.
558 Common Var(warn_missing_noreturn) Warning
559 Warn about functions which might be candidates for __attribute__((noreturn))
562 Common Var(warn_mudflap) Init(1) Warning
563 Warn about constructs not instrumented by -fmudflap
566 Common Var(warn_overflow) Init(1) Warning
567 Warn about overflow in arithmetic expressions
570 Common Var(warn_packed) Warning
571 Warn when the packed attribute has no effect on struct layout
574 Common Var(warn_padded) Warning
575 Warn when padding is required to align structure members
578 Common Var(warn_shadow) Warning
579 Warn when one local variable shadows another
582 Common Var(warn_stack_protect) Warning
583 Warn when not issuing stack smashing protection for some reason
586 Common Joined RejectNegative UInteger Var(warn_stack_usage) Init(-1) Warning
587 Warn if stack usage might be larger than specified amount
591 Warn about code which might break strict aliasing rules
594 Common Joined RejectNegative UInteger Var(warn_strict_aliasing) Init(-1) Warning
595 Warn about code which might break strict aliasing rules
599 Warn about optimizations that assume that signed overflow is undefined
602 Common Joined RejectNegative UInteger Var(warn_strict_overflow) Init(-1) Warning
603 Warn about optimizations that assume that signed overflow is undefined
605 Wsuggest-attribute=const
606 Common Var(warn_suggest_attribute_const) Warning
607 Warn about functions which might be candidates for __attribute__((const))
609 Wsuggest-attribute=pure
610 Common Var(warn_suggest_attribute_pure) Warning
611 Warn about functions which might be candidates for __attribute__((pure))
613 Wsuggest-attribute=noreturn
614 Common Var(warn_suggest_attribute_noreturn) Warning
615 Warn about functions which might be candidates for __attribute__((noreturn))
618 Common Var(warn_switch) Warning
619 Warn about enumerated switches, with no default, missing a case
622 Common Var(warn_switch_default) Warning
623 Warn about enumerated switches missing a \"default:\" statement
626 Common Var(warn_switch_enum) Warning
627 Warn about all enumerated switches missing a specific case
630 Common Var(warn_system_headers) Warning
631 Do not suppress warnings from system headers
634 Common Var(warn_trampolines) Warning
635 Warn whenever a trampoline is generated
637 ; FIXME. The following -Wthread-* flags are placeholders to prevent
638 ; confusing the compiler when applications are built with these flags.
639 ; Actual support for these flags is being implemented in the
640 ; thread-annotations branch.
642 Common Var(warn_thread_safety) Warning
643 Warn about potential thread safety issues when the code is annotated with thread safety attributes
645 Wthread-unguarded-var
646 Common Var(warn_thread_unguarded_var) Init(1) Warning
647 Warn about shared variables not properly protected by locks specified in the attributes
649 Wthread-unguarded-func
650 Common Var(warn_thread_unguarded_func) Init(1) Warning
651 Warn about function calls not properly protected by locks specified in the attributes
653 Wthread-mismatched-lock-order
654 Common Var(warn_thread_mismatched_lock_order) Init(1) Warning
655 Warn about lock acquisition order inconsistent with what specified in the attributes
657 Wthread-mismatched-lock-acq-rel
658 Common Var(warn_thread_mismatched_lock_acq_rel) Init(1) Warning
659 Warn about mismatched lock acquisition and release
661 Wthread-reentrant-lock
662 Common Var(warn_thread_reentrant_lock) Init(1) Warning
663 Warn about a lock being acquired recursively
665 Wthread-unsupported-lock-name
666 Common Var(warn_unsupported_lock_name) Init(0) Warning
667 Warn about uses of unsupported lock names in attributes
670 Common Var(warn_type_limits) Init(-1) Warning
671 Warn if a comparison is always true or always false due to the limited range of the data type
674 Common Var(warn_uninitialized) Init(-1) Warning
675 Warn about uninitialized automatic variables
678 Common Var(warn_maybe_uninitialized) Warning
679 Warn about maybe uninitialized automatic variables
683 Does nothing. Preserved for backward compatibility.
686 Common Var(warn_unused) Init(0) Warning
687 Enable all -Wunused- warnings
689 Wunused-but-set-parameter
690 Common Var(warn_unused_but_set_parameter) Init(-1) Warning
691 Warn when a function parameter is only set, otherwise unused
693 Wunused-but-set-variable
694 Common Var(warn_unused_but_set_variable) Init(-1) Warning
695 Warn when a variable is only set, otherwise unused
698 Common Var(warn_unused_function) Init(-1) Warning
699 Warn when a function is unused
702 Common Var(warn_unused_label) Init(-1) Warning
703 Warn when a label is unused
706 Common Var(warn_unused_parameter) Init(-1) Warning
707 Warn when a function parameter is unused
710 Common Var(warn_unused_value) Init(-1) Warning
711 Warn when an expression value is unused
714 Common Var(warn_unused_variable) Init(-1) Warning
715 Warn when a variable is unused
718 Common Var(warn_coverage_mismatch) Init(1) Warning
719 Warn in case profiles in -fprofile-use do not match
734 Common Separate Var(aux_info_file_name)
735 -aux-info <file> Emit declaration information into <file>
738 Common Joined Alias(aux-info)
741 Common Separate RejectDriver Var(aux_base_name)
744 Common Separate RejectDriver
754 -d<letters> Enable dumps from specific passes of the compiler
757 Common Separate Var(dump_base_name)
758 -dumpbase <file> Set the file basename to be used for dumps
761 Common Separate Var(dump_dir_name)
762 -dumpdir <dir> Set the directory name to be used for dumps
774 Driver Joined Separate
776 ; This option has historically been passed down to the linker by an
777 ; accident of a %{e*} spec, so ensure it continues to be passed down
778 ; as a single option. The supported option for this purpose is
779 ; -rdynamic. See PR 47390.
783 ; The version of the C++ ABI in use. The following values are allowed:
785 ; 0: The version of the ABI believed most conformant with the C++ ABI
786 ; specification. This ABI may change as bugs are discovered and fixed.
787 ; Therefore, 0 will not necessarily indicate the same ABI in different
790 ; 1: The version of the ABI first used in G++ 3.2.
792 ; 2: The version of the ABI first used in G++ 3.4 (and current default).
794 ; 3: The version of the ABI that fixes the missing underscore
795 ; in template non-type arguments of pointer type.
797 ; 4: The version of the ABI that introduces unambiguous mangling of
798 ; vector types. First selectable in G++ 4.5.
800 ; 5: The version of the ABI that ignores attribute const/noreturn
801 ; in function pointer mangling, and corrects mangling of decltype and
802 ; function parameters used in other parameters and the return type.
803 ; First selectable in G++ 4.6.
805 ; 6: The version of the ABI that doesn't promote scoped enums to int.
806 ; First selectable in G++ 4.7.
808 ; Additional positive integers will be assigned as new versions of
809 ; the ABI become the default version of the ABI.
811 Common Joined RejectNegative UInteger Var(flag_abi_version) Init(2)
814 Common Report Var(align_functions,0) Optimization UInteger
815 Align the start of functions
818 Common RejectNegative Joined UInteger Var(align_functions)
821 Common Report Var(align_jumps,0) Optimization UInteger
822 Align labels which are only reached by jumping
825 Common RejectNegative Joined UInteger Var(align_jumps)
828 Common Report Var(align_labels,0) Optimization UInteger
832 Common RejectNegative Joined UInteger Var(align_labels)
835 Common Report Var(align_loops,0) Optimization UInteger
836 Align the start of loops
839 Common RejectNegative Joined UInteger Var(align_loops)
843 Does nothing. Preserved for backward compatibility.
847 Does nothing. Preserved for backward compatibility.
849 fargument-noalias-global
851 Does nothing. Preserved for backward compatibility.
853 fargument-noalias-anything
855 Does nothing. Preserved for backward compatibility.
857 fasynchronous-unwind-tables
858 Common Report Var(flag_asynchronous_unwind_tables) Optimization
859 Generate unwind tables that are exact at each instruction boundary
862 Common Report Var(flag_auto_inc_dec) Init(1)
863 Generate auto-inc/dec instructions
865 ; -fcheck-bounds causes gcc to generate array bounds checks.
866 ; For C, C++ and ObjC: defaults off.
867 ; For Java: defaults to on.
868 ; For Fortran: defaults to off.
870 Common Report Var(flag_bounds_check)
871 Generate code to check bounds before indexing arrays
874 Common Report Var(flag_branch_on_count_reg) Init(1) Optimization
875 Replace add, compare, branch with branch on count register
877 fbranch-probabilities
878 Common Report Var(flag_branch_probabilities) Optimization
879 Use profiling information for branch probabilities
881 fbranch-target-load-optimize
882 Common Report Var(flag_branch_target_load_optimize) Optimization
883 Perform branch target load optimization before prologue / epilogue threading
885 fbranch-target-load-optimize2
886 Common Report Var(flag_branch_target_load_optimize2) Optimization
887 Perform branch target load optimization after prologue / epilogue threading
890 Common Report Var(flag_btr_bb_exclusive) Optimization
891 Restrict target load migration not to re-use registers in any basic block
894 Common Joined RejectNegative Var(common_deferred_options) Defer
895 -fcall-saved-<register> Mark <register> as being preserved across functions
898 Common Joined RejectNegative Var(common_deferred_options) Defer
899 -fcall-used-<register> Mark <register> as being corrupted by function calls
901 ; Nonzero for -fcaller-saves: allocate values in regs that need to
902 ; be saved across function calls, if that produces overall better code.
903 ; Optional now, so people can test it.
905 Common Report Var(flag_caller_saves) Optimization
906 Save registers around function calls
909 Common Report Var(flag_check_data_deps)
910 Compare the results of several data dependence analyzers.
912 fcombine-stack-adjustments
913 Common Report Var(flag_combine_stack_adjustments) Optimization
914 Looks for opportunities to reduce stack adjustments and stack references.
917 Common Report Var(flag_no_common,0) Optimization
918 Do not put uninitialized globals in the common section
922 ; Converted by the driver to -fcompare-debug= options.
925 Common Driver JoinedOrMissing RejectNegative Var(flag_compare_debug_opt)
926 -fcompare-debug[=<opts>] Compile with and without e.g. -gtoggle, and compare the final-insns dump
928 fcompare-debug-second
929 Common Driver RejectNegative Var(flag_compare_debug)
930 Run only the second compilation of -fcompare-debug
933 Common Report Var(flag_compare_elim_after_reload) Optimization
934 Perform comparison elimination after register allocation has finished
937 Common Var(flag_conserve_stack) Optimization
938 Do not perform optimizations increasing noticeably stack usage
941 Common Report Var(flag_cprop_registers) Optimization
942 Perform a register copy-propagation optimization pass
945 Common Report Var(flag_crossjumping) Optimization
946 Perform cross-jumping optimization
949 Common Report Var(flag_cse_follow_jumps) Optimization
950 When running CSE, follow jumps to their targets
954 Does nothing. Preserved for backward compatibility.
957 Common Report Var(flag_cx_limited_range) Optimization SetByCombined
958 Omit range reduction step when performing complex division
961 Common Report Var(flag_cx_fortran_rules) Optimization
962 Complex multiplication and division follow Fortran rules
965 Common Report Var(flag_data_sections) Optimization
966 Place data items into their own section
969 Common Report Var(common_deferred_options) Defer
970 List all available debugging counters with their limits and counts.
973 Common RejectNegative Joined Var(common_deferred_options) Defer
974 -fdbg-cnt=<counter>:<limit>[,<counter>:<limit>,...] Set the debug counter limit.
977 Common Joined RejectNegative Var(common_deferred_options) Defer
978 Map one directory name to another in debug information
981 Common Report Var(flag_debug_types_section) Init(1)
982 Output .debug_types section when using DWARF v4 debuginfo.
984 ; Nonzero for -fdefer-pop: don't pop args after each function call
985 ; instead save them up to pop many calls' args with one insns.
987 Common Report Var(flag_defer_pop) Optimization
988 Defer popping functions args from stack until later
991 Common Report Var(flag_delayed_branch) Optimization
992 Attempt to fill delay slots of branch instructions
994 fdelete-null-pointer-checks
995 Common Report Var(flag_delete_null_pointer_checks) Init(1) Optimization
996 Delete useless null pointer checks
999 Common Report Var(flag_devirtualize) Optimization
1000 Try to convert virtual calls to direct ones.
1002 fdiagnostics-show-location=
1003 Common Joined RejectNegative Enum(diagnostic_prefixing_rule)
1004 -fdiagnostics-show-location=[once|every-line] How often to emit source location at the beginning of line-wrapped diagnostics
1006 ; Required for these enum values.
1011 Name(diagnostic_prefixing_rule) Type(int)
1014 Enum(diagnostic_prefixing_rule) String(once) Value(DIAGNOSTICS_SHOW_PREFIX_ONCE)
1017 Enum(diagnostic_prefixing_rule) String(every-line) Value(DIAGNOSTICS_SHOW_PREFIX_EVERY_LINE)
1019 fdiagnostics-show-option
1020 Common Var(flag_diagnostics_show_option) Init(1)
1021 Amend appropriate diagnostic messages with the command line option that controls them
1024 Common Joined RejectNegative Var(common_deferred_options) Defer
1025 -fdump-<type> Dump various compiler internals to a file
1028 Driver RejectNegative
1031 Common RejectNegative Joined Var(flag_dump_final_insns)
1032 -fdump-final-insns=filename Dump to filename the insns at the end of translation
1035 Common RejectNegative Joined Var(flag_dump_go_spec)
1036 -fdump-go-spec=filename Write all declarations to file as Go code
1039 Common Report Var(flag_dump_noaddr)
1040 Suppress output of addresses in debugging dumps
1043 Common Report Var(flag_dump_unnumbered)
1044 Suppress output of instruction numbers, line number notes and addresses in debugging dumps
1046 fdump-unnumbered-links
1047 Common Report Var(flag_dump_unnumbered_links)
1048 Suppress output of previous and next insn numbers in debugging dumps
1051 Common Report Var(flag_dwarf2_cfi_asm) Init(HAVE_GAS_CFI_DIRECTIVE)
1052 Enable CFI tables via GAS assembler directives.
1055 Common Report Var(flag_early_inlining) Init(1) Optimization
1056 Perform early inlining
1058 feliminate-dwarf2-dups
1059 Common Report Var(flag_eliminate_dwarf2_dups)
1060 Perform DWARF2 duplicate elimination
1063 Common Report Var(flag_ipa_sra) Init(0) Optimization
1064 Perform interprocedural reduction of aggregates
1066 feliminate-unused-debug-symbols
1067 Common Report Var(flag_debug_only_used_symbols)
1068 Perform unused type elimination in debug info
1070 feliminate-unused-debug-types
1071 Common Report Var(flag_eliminate_unused_debug_types) Init(1)
1072 Perform unused type elimination in debug info
1074 femit-class-debug-always
1075 Common Report Var(flag_emit_class_debug_always) Init(0)
1076 Do not suppress C++ class debug information.
1079 Common Report Var(flag_exceptions) Optimization
1080 Enable exception handling
1082 fexpensive-optimizations
1083 Common Report Var(flag_expensive_optimizations) Optimization
1084 Perform a number of minor, expensive optimizations
1087 Common Joined RejectNegative Enum(excess_precision) Var(flag_excess_precision_cmdline) Init(EXCESS_PRECISION_DEFAULT)
1088 -fexcess-precision=[fast|standard] Specify handling of excess floating-point precision
1091 Name(excess_precision) Type(enum excess_precision) UnknownError(unknown excess precision style %qs)
1094 Enum(excess_precision) String(fast) Value(EXCESS_PRECISION_FAST)
1097 Enum(excess_precision) String(standard) Value(EXCESS_PRECISION_STANDARD)
1103 Common Report Var(flag_finite_math_only) Optimization SetByCombined
1104 Assume no NaNs or infinities are generated
1107 Common Joined RejectNegative Var(common_deferred_options) Defer
1108 -ffixed-<register> Mark <register> as being unavailable to the compiler
1111 Common Report Var(flag_float_store) Optimization
1112 Don't allocate floats and doubles in extended-precision registers
1116 Does nothing. Preserved for backward compatibility.
1119 Common Report Var(flag_forward_propagate) Optimization
1120 Perform a forward propagation pass on RTL
1123 Common Joined RejectNegative Enum(fp_contract_mode) Var(flag_fp_contract_mode) Init(FP_CONTRACT_FAST)
1124 -ffp-contract=[off|on|fast] Perform floating-point expression contraction.
1127 Name(fp_contract_mode) Type(enum fp_contract_mode) UnknownError(unknown floating point contraction style %qs)
1130 Enum(fp_contract_mode) String(off) Value(FP_CONTRACT_OFF)
1132 ; Not implemented, fall back to conservative FP_CONTRACT_OFF.
1134 Enum(fp_contract_mode) String(on) Value(FP_CONTRACT_OFF)
1137 Enum(fp_contract_mode) String(fast) Value(FP_CONTRACT_FAST)
1139 ; Nonzero means don't put addresses of constant functions in registers.
1140 ; Used for compiling the Unix kernel, where strange substitutions are
1141 ; done on the assembly output.
1143 Common Report Var(flag_no_function_cse,0)
1144 Allow function addresses to be held in registers
1147 Common Report Var(flag_function_sections)
1148 Place each function into its own section
1151 Common Report Var(flag_gcse) Optimization
1152 Perform global common subexpression elimination
1155 Common Report Var(flag_gcse_lm) Init(1) Optimization
1156 Perform enhanced load motion during global common subexpression elimination
1159 Common Report Var(flag_gcse_sm) Init(0) Optimization
1160 Perform store motion after global common subexpression elimination
1163 Common Report Var(flag_gcse_las) Init(0) Optimization
1164 Perform redundant load after store elimination in global common subexpression
1168 Common Report Var(flag_gcse_after_reload) Optimization
1169 Perform global common subexpression elimination after register allocation
1172 ; This option is not documented yet as its semantics will change.
1174 Common Report Var(flag_graphite)
1175 Enable in and out of Graphite representation
1178 Common Report Var(flag_graphite_identity) Optimization
1179 Enable Graphite Identity transformation
1181 floop-parallelize-all
1182 Common Report Var(flag_loop_parallelize_all) Optimization
1183 Mark all loops as parallel
1186 Common Report Var(flag_loop_strip_mine) Optimization
1187 Enable Loop Strip Mining transformation
1190 Common Report Var(flag_loop_interchange) Optimization
1191 Enable Loop Interchange transformation
1194 Common Report Var(flag_loop_block) Optimization
1195 Enable Loop Blocking transformation
1198 Common Report Var(flag_loop_flatten) Optimization
1199 Enable Loop Flattening transformation
1201 fstrict-volatile-bitfields
1202 Common Report Var(flag_strict_volatile_bitfields) Init(-1)
1203 Force bitfield accesses to match their type width
1205 fguess-branch-probability
1206 Common Report Var(flag_guess_branch_prob) Optimization
1207 Enable guessing of branch probabilities
1209 ; Nonzero means ignore `#ident' directives. 0 means handle them.
1210 ; Generate position-independent code for executables if possible
1211 ; On SVR4 targets, it also controls whether or not to emit a
1212 ; string identifying the compiler.
1214 Common Report Var(flag_no_ident,0)
1215 Process #ident directives
1218 Common Report Var(flag_if_conversion) Optimization
1219 Perform conversion of conditional jumps to branchless equivalents
1222 Common Report Var(flag_if_conversion2) Optimization
1223 Perform conversion of conditional jumps to conditional execution
1225 ftree-loop-if-convert
1226 Common Report Var(flag_tree_loop_if_convert) Init(-1) Optimization
1227 Convert conditional jumps in innermost loops to branchless equivalents
1229 ftree-loop-if-convert-stores
1230 Common Report Var(flag_tree_loop_if_convert_stores) Optimization
1231 Also if-convert conditional jumps containing memory writes
1233 ; -finhibit-size-directive inhibits output of .size for ELF.
1234 ; This is used only for compiling crtstuff.c,
1235 ; and it may be extended to other effects
1236 ; needed for crtstuff.c on other systems.
1237 finhibit-size-directive
1238 Common Report Var(flag_inhibit_size_directive)
1239 Do not generate .size directives
1242 Common Report Var(flag_indirect_inlining)
1243 Perform indirect inlining
1245 ; Nonzero means that functions declared `inline' will be treated
1246 ; as `static'. Prevents generation of zillions of copies of unused
1247 ; static inline functions; instead, `inlines' are written out
1248 ; only when actually used. Used in conjunction with -g. Also
1249 ; does the right thing with #pragma interface.
1251 Common Report Var(flag_no_inline,0) Init(0)
1252 Pay attention to the \"inline\" keyword
1254 finline-small-functions
1255 Common Report Var(flag_inline_small_functions) Optimization
1256 Integrate simple functions into their callers when code size is known to not growth
1259 Common Report Var(flag_inline_functions) Optimization
1260 Integrate simple functions into their callers
1262 finline-functions-called-once
1263 Common Report Var(flag_inline_functions_called_once) Init(1) Optimization
1264 Integrate functions called once into their callers
1267 Common RejectNegative Joined Alias(finline-limit=)
1270 Common RejectNegative Joined UInteger
1271 -finline-limit=<number> Limit the size of inlined functions to <number>
1273 finstrument-functions
1274 Common Report Var(flag_instrument_function_entry_exit)
1275 Instrument function entry and exit with profiling calls
1277 finstrument-functions-exclude-function-list=
1278 Common RejectNegative Joined
1279 -finstrument-functions-exclude-function-list=name,... Do not instrument listed functions
1281 finstrument-functions-exclude-file-list=
1282 Common RejectNegative Joined
1283 -finstrument-functions-exclude-file-list=filename,... Do not instrument functions listed in files
1286 Common Report Var(flag_ipa_cp) Optimization
1287 Perform Interprocedural constant propagation
1290 Common Report Var(flag_ipa_cp_clone) Optimization
1291 Perform cloning to make Interprocedural constant propagation stronger
1294 Common Report Var(flag_ipa_profile) Init(0) Optimization
1295 Perform interprocedural profile propagation
1298 Common Report Var(flag_ipa_pta) Init(0) Optimization
1299 Perform interprocedural points-to analysis
1302 Common Report Var(flag_ipa_pure_const) Init(0) Optimization
1303 Discover pure and const functions
1306 Common Report Var(flag_ipa_reference) Init(0) Optimization
1307 Discover readonly and non addressable static variables
1310 Common Report Var(flag_ipa_matrix_reorg) Optimization
1311 Perform matrix layout flattening and transposing based
1312 on profiling information.
1316 Does nothing. Preserved for backward compatibility.
1319 Common Joined RejectNegative Enum(ira_algorithm) Var(flag_ira_algorithm) Init(IRA_ALGORITHM_CB)
1320 -fira-algorithm=[CB|priority] Set the used IRA algorithm
1323 Name(ira_algorithm) Type(enum ira_algorithm) UnknownError(unknown IRA algorithm %qs)
1326 Enum(ira_algorithm) String(CB) Value(IRA_ALGORITHM_CB)
1329 Enum(ira_algorithm) String(priority) Value(IRA_ALGORITHM_PRIORITY)
1332 Common Joined RejectNegative Enum(ira_region) Var(flag_ira_region) Init(IRA_REGION_MIXED)
1333 -fira-region=[one|all|mixed] Set regions for IRA
1336 Name(ira_region) Type(enum ira_region) UnknownError(unknown IRA region %qs)
1339 Enum(ira_region) String(one) Value(IRA_REGION_ONE)
1342 Enum(ira_region) String(all) Value(IRA_REGION_ALL)
1345 Enum(ira_region) String(mixed) Value(IRA_REGION_MIXED)
1348 Common Report Var(flag_ira_loop_pressure)
1349 Use IRA based register pressure calculation
1350 in RTL loop optimizations.
1352 fira-share-save-slots
1353 Common Report Var(flag_ira_share_save_slots) Init(1)
1354 Share slots for saving different hard registers.
1356 fira-share-spill-slots
1357 Common Report Var(flag_ira_share_spill_slots) Init(1)
1358 Share stack slots for spilled pseudo-registers.
1361 Common RejectNegative Joined UInteger Var(flag_ira_verbose) Init(5)
1362 -fira-verbose=<number> Control IRA's level of diagnostic messages.
1365 Common Report Var(flag_ivopts) Init(1) Optimization
1366 Optimize induction variables on trees
1369 Common Var(flag_jump_tables) Init(1) Optimization
1370 Use jump tables for sufficiently large switch statements
1372 fkeep-inline-functions
1373 Common Report Var(flag_keep_inline_functions)
1374 Generate code for functions even if they are fully inlined
1377 Common Report Var(flag_keep_static_consts) Init(1)
1378 Emit static const variables even if they are not used
1381 Common Report Var(flag_leading_underscore) Init(-1)
1382 Give external symbols a leading underscore
1386 Does nothing. Preserved for backward compatibility.
1390 Enable link-time optimization.
1393 Common RejectNegative Joined Var(flag_lto)
1394 Link-time optimization with number of parallel jobs or jobserver.
1397 Common Var(flag_lto_partition_1to1)
1398 Partition functions and vars at linktime based on object files they originate from
1400 flto-partition=balanced
1401 Common Var(flag_lto_partition_balanced)
1402 Partition functions and vars at linktime into approximately same sized buckets
1405 Common Var(flag_lto_partition_none)
1406 Disable partioning and streaming
1408 ; The initial value of -1 comes from Z_DEFAULT_COMPRESSION in zlib.h.
1409 flto-compression-level=
1410 Common Joined RejectNegative UInteger Var(flag_lto_compression_level) Init(-1)
1411 -flto-compression-level=<number> Use zlib compression level <number> for IL
1414 Common Report Var(flag_lto_report) Init(0) Optimization
1415 Report various link-time optimization statistics
1418 Common Report Var(flag_errno_math) Init(1) Optimization SetByCombined
1419 Set errno after built-in math functions
1422 Common Joined RejectNegative UInteger Var(flag_max_errors)
1423 -fmax-errors=<number> Maximum number of errors to report
1426 Common Report Var(mem_report)
1427 Report on permanent memory allocation
1429 ; This will attempt to merge constant section constants, if 1 only
1430 ; string constants and constants from constant pool, if 2 also constant
1432 fmerge-all-constants
1433 Common Report Var(flag_merge_constants,2) Init(1) Optimization
1434 Attempt to merge identical constants and constant variables
1437 Common Report Var(flag_merge_constants,1) Optimization
1438 Attempt to merge identical constants across compilation units
1440 fmerge-debug-strings
1441 Common Report Var(flag_merge_debug_strings) Init(1)
1442 Attempt to merge identical debug strings across compilation units
1445 Common RejectNegative Joined UInteger
1446 -fmessage-length=<number> Limit diagnostics to <number> characters per line. 0 suppresses line-wrapping
1449 Common Report Var(flag_modulo_sched) Optimization
1450 Perform SMS based modulo scheduling before the first scheduling pass
1452 fmodulo-sched-allow-regmoves
1453 Common Report Var(flag_modulo_sched_allow_regmoves)
1454 Perform SMS based modulo scheduling with register moves allowed
1456 fmove-loop-invariants
1457 Common Report Var(flag_move_loop_invariants) Init(1) Optimization
1458 Move loop invariant computations out of loops
1461 Common RejectNegative Report Var(flag_mudflap)
1462 Add mudflap bounds-checking instrumentation for single-threaded program
1465 Common RejectNegative Report Var(flag_mudflap,2)
1466 Add mudflap bounds-checking instrumentation for multi-threaded program
1469 Common RejectNegative Report Var(flag_mudflap_ignore_reads)
1470 Ignore read operations when inserting mudflap instrumentation
1473 Common Var(flag_dce) Init(1) Optimization
1474 Use the RTL dead code elimination pass
1477 Common Var(flag_dse) Init(1) Optimization
1478 Use the RTL dead store elimination pass
1480 freschedule-modulo-scheduled-loops
1481 Common Report Var(flag_resched_modulo_sched) Optimization
1482 Enable/Disable the traditional scheduling in loops that already passed modulo scheduling
1484 fnon-call-exceptions
1485 Common Report Var(flag_non_call_exceptions) Optimization
1486 Support synchronous non-call exceptions
1489 Common Report Var(flag_omit_frame_pointer) Optimization
1490 When possible do not generate stack frames
1492 foptimize-register-move
1493 Common Report Var(flag_regmove) Optimization
1494 Do the full register move optimization pass
1496 foptimize-sibling-calls
1497 Common Report Var(flag_optimize_sibling_calls) Optimization
1498 Optimize sibling and tail recursive calls
1501 Common Report Var(flag_partial_inlining)
1502 Perform partial inlining
1505 Common Report Var(pre_ipa_mem_report)
1506 Report on memory allocation before interprocedural optimization
1508 fpost-ipa-mem-report
1509 Common Report Var(post_ipa_mem_report)
1510 Report on memory allocation before interprocedural optimization
1513 Common Report Var(flag_pack_struct) Optimization
1514 Pack structure members together without holes
1517 Common RejectNegative Joined UInteger Optimization
1518 -fpack-struct=<number> Set initial maximum structure member alignment
1521 Common Report Var(flag_pcc_struct_return,1) Init(DEFAULT_PCC_STRUCT_RETURN)
1522 Return small aggregates in memory, not registers
1525 Common Report Var(flag_peel_loops) Optimization
1526 Perform loop peeling
1529 Common Report Var(flag_no_peephole,0) Optimization
1530 Enable machine specific peephole optimizations
1533 Common Report Var(flag_peephole2) Optimization
1534 Enable an RTL peephole pass before sched2
1537 Common Report Var(flag_pic,2)
1538 Generate position-independent code if possible (large mode)
1541 Common Report Var(flag_pie,2)
1542 Generate position-independent code for executables if possible (large mode)
1545 Common Report Var(flag_pic,1)
1546 Generate position-independent code if possible (small mode)
1549 Common Report Var(flag_pie,1)
1550 Generate position-independent code for executables if possible (small mode)
1553 Common Joined RejectNegative Var(common_deferred_options) Defer
1554 Specify a plugin to load
1557 Common Joined RejectNegative Var(common_deferred_options) Defer
1558 -fplugin-arg-<name>-<key>[=<value>] Specify argument <key>=<value> for plugin <name>
1560 fpredictive-commoning
1561 Common Report Var(flag_predictive_commoning) Optimization
1562 Run predictive commoning optimization.
1564 fprefetch-loop-arrays
1565 Common Report Var(flag_prefetch_loop_arrays) Init(-1) Optimization
1566 Generate prefetch instructions, if available, for arrays in loops
1569 Common Report Var(profile_flag)
1570 Enable basic program profiling code
1573 Common Report Var(profile_arc_flag)
1574 Insert arc-based program profiling code
1577 Common Joined RejectNegative Var(profile_data_prefix)
1578 Set the top-level directory for storing the profile data.
1579 The default is 'pwd'.
1582 Common Report Var(flag_profile_correction)
1583 Enable correction of flow inconsistent profile data input
1587 Enable common options for generating profile info for profile feedback directed optimizations
1590 Common Joined RejectNegative
1591 Enable common options for generating profile info for profile feedback directed optimizations, and set -fprofile-dir=
1594 Common Var(flag_profile_use)
1595 Enable common options for performing profile feedback directed optimizations
1598 Common Joined RejectNegative
1599 Enable common options for performing profile feedback directed optimizations, and set -fprofile-dir=
1602 Common Report Var(flag_profile_values)
1603 Insert code to profile values of expressions
1606 Common Var(common_deferred_options) Defer
1609 Common Joined RejectNegative Var(common_deferred_options) Defer
1610 -frandom-seed=<string> Make compile reproducible using <string>
1612 ; This switch causes the command line that was used to create an
1613 ; object file to be recorded into the object file. The exact format
1614 ; of this recording is target and binary file format dependent.
1615 ; It is related to the -fverbose-asm switch, but that switch only
1616 ; records information in the assembler output file as comments, so
1617 ; they never reach the object file.
1618 frecord-gcc-switches
1619 Common Report Var(flag_record_gcc_switches)
1620 Record gcc command line switches in the object file.
1623 Common Report Var(flag_pcc_struct_return,0) Optimization
1624 Return small aggregates in registers
1627 Common Report Var(flag_regmove) Optimization
1628 Enables a register move optimization
1631 Common Report Var(flag_rename_registers) Init(2) Optimization
1632 Perform a register renaming optimization pass
1635 Common Report Var(flag_reorder_blocks) Optimization
1636 Reorder basic blocks to improve code placement
1638 freorder-blocks-and-partition
1639 Common Report Var(flag_reorder_blocks_and_partition) Optimization
1640 Reorder basic blocks and partition into hot and cold sections
1643 Common Report Var(flag_reorder_functions) Optimization
1644 Reorder functions to improve code placement
1646 frerun-cse-after-loop
1647 Common Report Var(flag_rerun_cse_after_loop) Optimization
1648 Add a common subexpression elimination pass after loop optimizations
1652 Does nothing. Preserved for backward compatibility.
1655 Common Report Var(flag_rounding_math) Optimization SetByCombined
1656 Disable optimizations that assume default FP rounding behavior
1659 Common Report Var(flag_schedule_interblock) Init(1) Optimization
1660 Enable scheduling across basic blocks
1663 Common Report Var(flag_sched_pressure) Init(0) Optimization
1664 Enable register pressure sensitive insn scheduling
1667 Common Report Var(flag_schedule_speculative) Init(1) Optimization
1668 Allow speculative motion of non-loads
1671 Common Report Var(flag_schedule_speculative_load) Optimization
1672 Allow speculative motion of some loads
1674 fsched-spec-load-dangerous
1675 Common Report Var(flag_schedule_speculative_load_dangerous) Optimization
1676 Allow speculative motion of more loads
1679 Common RejectNegative Joined UInteger Var(sched_verbose_param)
1680 -fsched-verbose=<number> Set the verbosity level of the scheduler
1682 fsched2-use-superblocks
1683 Common Report Var(flag_sched2_use_superblocks) Optimization
1684 If scheduling post reload, do superblock scheduling
1688 Does nothing. Preserved for backward compatibility.
1691 Common Report Var(flag_schedule_insns) Optimization
1692 Reschedule instructions before register allocation
1695 Common Report Var(flag_schedule_insns_after_reload) Optimization
1696 Reschedule instructions after register allocation
1698 ; This flag should be on when a target implements non-trivial
1699 ; scheduling hooks, maybe saving some information for its own sake.
1700 ; On IA64, for example, this is used for correct bundling.
1701 fselective-scheduling
1702 Common Report Var(flag_selective_scheduling) Optimization
1703 Schedule instructions using selective scheduling algorithm
1705 fselective-scheduling2
1706 Common Report Var(flag_selective_scheduling2) Optimization
1707 Run selective scheduling after reload
1709 fsel-sched-pipelining
1710 Common Report Var(flag_sel_sched_pipelining) Init(0) Optimization
1711 Perform software pipelining of inner loops during selective scheduling
1713 fsel-sched-pipelining-outer-loops
1714 Common Report Var(flag_sel_sched_pipelining_outer_loops) Init(0) Optimization
1715 Perform software pipelining of outer loops during selective scheduling
1717 fsel-sched-reschedule-pipelined
1718 Common Report Var(flag_sel_sched_reschedule_pipelined) Init(0) Optimization
1719 Reschedule pipelined regions without pipelining
1721 ; sched_stalled_insns means that insns can be moved prematurely from the queue
1722 ; of stalled insns into the ready list.
1723 fsched-stalled-insns
1724 Common Report Var(flag_sched_stalled_insns) Optimization UInteger
1725 Allow premature scheduling of queued insns
1727 fsched-stalled-insns=
1728 Common RejectNegative Joined UInteger
1729 -fsched-stalled-insns=<number> Set number of queued insns that can be prematurely scheduled
1731 ; sched_stalled_insns_dep controls how many recently scheduled cycles will
1732 ; be examined for a dependency on a stalled insn that is candidate for
1733 ; premature removal from the queue of stalled insns into the ready list (has
1734 ; an effect only if the flag 'sched_stalled_insns' is set).
1735 fsched-stalled-insns-dep
1736 Common Report Var(flag_sched_stalled_insns_dep,1) Init(1) Optimization UInteger
1737 Set dependence distance checking in premature scheduling of queued insns
1739 fsched-stalled-insns-dep=
1740 Common RejectNegative Joined UInteger
1741 -fsched-stalled-insns-dep=<number> Set dependence distance checking in premature scheduling of queued insns
1743 fsched-group-heuristic
1744 Common Report Var(flag_sched_group_heuristic) Init(1) Optimization
1745 Enable the group heuristic in the scheduler
1747 fsched-critical-path-heuristic
1748 Common Report Var(flag_sched_critical_path_heuristic) Init(1) Optimization
1749 Enable the critical path heuristic in the scheduler
1751 fsched-spec-insn-heuristic
1752 Common Report Var(flag_sched_spec_insn_heuristic) Init(1) Optimization
1753 Enable the speculative instruction heuristic in the scheduler
1755 fsched-rank-heuristic
1756 Common Report Var(flag_sched_rank_heuristic) Init(1) Optimization
1757 Enable the rank heuristic in the scheduler
1759 fsched-last-insn-heuristic
1760 Common Report Var(flag_sched_last_insn_heuristic) Init(1) Optimization
1761 Enable the last instruction heuristic in the scheduler
1763 fsched-dep-count-heuristic
1764 Common Report Var(flag_sched_dep_count_heuristic) Init(1) Optimization
1765 Enable the dependent count heuristic in the scheduler
1768 Common Report Var(flag_section_anchors) Optimization
1769 Access data in the same section from shared anchor points
1773 Does nothing. Preserved for backward compatibility.
1776 Common Report Var(flag_zee) Init(0)
1777 Eliminate redundant zero extensions on targets that support implicit extensions.
1780 Common Report Var(flag_show_column) Init(1)
1781 Show column numbers in diagnostics, when available. Default on
1784 Common Report Var(flag_signaling_nans) Optimization SetByCombined
1785 Disable optimizations observable by IEEE signaling NaNs
1788 Common Report Var(flag_signed_zeros) Init(1) Optimization SetByCombined
1789 Disable floating point optimizations that ignore the IEEE signedness of zero
1791 fsingle-precision-constant
1792 Common Report Var(flag_single_precision_constant) Optimization
1793 Convert floating point constants to single precision constants
1795 fsplit-ivs-in-unroller
1796 Common Report Var(flag_split_ivs_in_unroller) Init(1) Optimization
1797 Split lifetimes of induction variables when loops are unrolled
1800 Common Report Var(flag_split_stack) Init(-1)
1801 Generate discontiguous stack frames
1804 Common Report Var(flag_split_wide_types) Optimization
1805 Split wide types into independent registers
1807 fvariable-expansion-in-unroller
1808 Common Report Var(flag_variable_expansion_in_unroller) Optimization
1809 Apply variable expansion when loops are unrolled
1812 Common Report RejectNegative Joined
1813 -fstack-check=[no|generic|specific] Insert stack checking code into the program
1816 Common Alias(fstack-check=, specific, no)
1817 Insert stack checking code into the program. Same as -fstack-check=specific
1820 Common Var(common_deferred_options) Defer
1822 fstack-limit-register=
1823 Common RejectNegative Joined Var(common_deferred_options) Defer
1824 -fstack-limit-register=<register> Trap if the stack goes past <register>
1826 fstack-limit-symbol=
1827 Common RejectNegative Joined Var(common_deferred_options) Defer
1828 -fstack-limit-symbol=<name> Trap if the stack goes past symbol <name>
1831 Common Report Var(flag_stack_protect, 1)
1832 Use propolice as a stack protection method
1834 fstack-protector-all
1835 Common Report RejectNegative Var(flag_stack_protect, 2)
1836 Use a stack protection method for every function
1839 Common RejectNegative Var(flag_stack_usage)
1840 Output stack usage information on a per-function basis
1844 Does nothing. Preserved for backward compatibility.
1846 ; Nonzero if we should do (language-dependent) alias analysis.
1847 ; Typically, this analysis will assume that expressions of certain
1848 ; types do not alias expressions of certain other types. Only used
1849 ; if alias analysis (in general) is enabled.
1851 Common Report Var(flag_strict_aliasing) Optimization
1852 Assume strict aliasing rules apply
1855 Common Report Var(flag_strict_overflow)
1856 Treat signed overflow as undefined
1859 Common Report Var(flag_syntax_only)
1860 Check for syntax errors, then stop
1863 Common Report Var(flag_test_coverage)
1864 Create data files needed by \"gcov\"
1867 Common Report Var(flag_thread_jumps) Optimization
1868 Perform jump threading optimizations
1871 Common Report Var(time_report)
1872 Report the time taken by each compiler pass
1875 Common Joined RejectNegative Enum(tls_model) Var(flag_tls_default) Init(TLS_MODEL_GLOBAL_DYNAMIC)
1876 -ftls-model=[global-dynamic|local-dynamic|initial-exec|local-exec] Set the default thread-local storage code generation model
1879 Name(tls_model) Type(enum tls_model) UnknownError(unknown TLS model %qs)
1882 Enum(tls_model) String(global-dynamic) Value(TLS_MODEL_GLOBAL_DYNAMIC)
1885 Enum(tls_model) String(local-dynamic) Value(TLS_MODEL_LOCAL_DYNAMIC)
1888 Enum(tls_model) String(initial-exec) Value(TLS_MODEL_INITIAL_EXEC)
1891 Enum(tls_model) String(local-exec) Value(TLS_MODEL_LOCAL_EXEC)
1894 Common Report Var(flag_toplevel_reorder) Init(2) Optimization
1895 Reorder top level functions, variables, and asms
1898 Common Report Var(flag_tracer)
1899 Perform superblock formation via tail duplication
1901 ; Zero means that floating-point math operations cannot generate a
1902 ; (user-visible) trap. This is the case, for example, in nonstop
1903 ; IEEE 754 arithmetic.
1905 Common Report Var(flag_trapping_math) Init(1) Optimization SetByCombined
1906 Assume floating-point operations can trap
1909 Common Report Var(flag_trapv) Optimization
1910 Trap for signed overflow in addition, subtraction and multiplication
1913 Common Report Var(flag_tree_ccp) Optimization
1914 Enable SSA-CCP optimization on trees
1917 Common Report Var(flag_tree_bit_ccp) Optimization
1918 Enable SSA-BIT-CCP optimization on trees
1922 Does nothing. Preserved for backward compatibility.
1925 Common Report Var(flag_tree_ch) Optimization
1926 Enable loop header copying on trees
1929 Common Report Var(flag_tree_copyrename) Optimization
1930 Replace SSA temporaries with better names in copies
1933 Common Report Var(flag_tree_copy_prop) Optimization
1934 Enable copy propagation on trees
1936 ftree-store-copy-prop
1938 Does nothing. Preserved for backward compatibility.
1941 Common Report Var(flag_tree_cselim) Init(2) Optimization
1942 Transform condition stores into unconditional ones
1944 ftree-switch-conversion
1945 Common Report Var(flag_tree_switch_conversion) Optimization
1946 Perform conversions of switch initializations.
1949 Common Report Var(flag_tree_dce) Optimization
1950 Enable SSA dead code elimination optimization on trees
1952 ftree-dominator-opts
1953 Common Report Var(flag_tree_dom) Optimization
1954 Enable dominator optimizations
1957 Common Report Var(flag_tree_dse) Optimization
1958 Enable dead store elimination
1961 Common Report Var(flag_tree_forwprop) Init(1) Optimization
1962 Enable forward propagation on trees
1965 Common Report Var(flag_tree_fre) Optimization
1966 Enable Full Redundancy Elimination (FRE) on trees
1968 ftree-loop-distribution
1969 Common Report Var(flag_tree_loop_distribution) Optimization
1970 Enable loop distribution on trees
1972 ftree-loop-distribute-patterns
1973 Common Report Var(flag_tree_loop_distribute_patterns) Optimization
1974 Enable loop distribution for patterns transformed into a library call
1977 Common Report Var(flag_tree_loop_im) Init(1) Optimization
1978 Enable loop invariant motion on trees
1981 Common Alias(floop-interchange)
1982 Enable loop interchange transforms. Same as -floop-interchange
1985 Common Report Var(flag_tree_loop_ivcanon) Init(1) Optimization
1986 Create canonical induction variables in loops
1989 Common Report Var(flag_tree_loop_optimize) Init(1) Optimization
1990 Enable loop optimizations on tree level
1992 ftree-parallelize-loops=
1993 Common Report Joined RejectNegative UInteger Var(flag_tree_parallelize_loops) Init(1)
1994 Enable automatic parallelization of loops
1997 Common Report Var(flag_tree_phiprop) Init(1) Optimization
1998 Enable hoisting loads from conditional pointers.
2001 Common Report Var(flag_tree_pre) Optimization
2002 Enable SSA-PRE optimization on trees
2005 Common Report Var(flag_tree_pta) Init(1) Optimization
2006 Perform function-local points-to analysis on trees.
2009 Common Report Var(flag_tree_reassoc) Init(1) Optimization
2010 Enable reassociation on tree level
2014 Does nothing. Preserved for backward compatibility.
2017 Common Report Var(flag_tree_sink) Optimization
2018 Enable SSA code sinking on trees
2021 Common Report Var(flag_tree_sra) Optimization
2022 Perform scalar replacement of aggregates
2025 Common Report Var(flag_tree_ter) Optimization
2026 Replace temporary expressions in the SSA->normal pass
2029 Common Report Var(flag_tree_live_range_split) Optimization
2030 Perform live range splitting during the SSA->normal pass
2033 Common Report Var(flag_tree_vrp) Init(0) Optimization
2034 Perform Value Range Propagation on trees
2036 fstrict-enum-precision
2037 Common Report Var(flag_strict_enum_precision) Init(1) Optimization
2038 Perform transformations based on enum precision
2041 Common Report Var(flag_unit_at_a_time) Init(1) Optimization
2042 Compile whole compilation unit at a time
2045 Common Report Var(flag_unroll_loops) Optimization
2046 Perform loop unrolling when iteration count is known
2049 Common Report Var(flag_unroll_all_loops) Optimization
2050 Perform loop unrolling for all loops
2052 ; Nonzero means that loop optimizer may assume that the induction variables
2053 ; that control loops do not overflow and that the loops with nontrivial
2054 ; exit condition are not infinite
2055 funsafe-loop-optimizations
2056 Common Report Var(flag_unsafe_loop_optimizations) Optimization
2057 Allow loop optimizations to assume that the loops behave in normal way
2060 Common Report Var(flag_associative_math) SetByCombined
2061 Allow optimization for floating-point arithmetic which may change the
2062 result of the operation due to rounding.
2065 Common Report Var(flag_reciprocal_math) SetByCombined
2066 Same as -fassociative-math for expressions which include division.
2068 ; Nonzero means that unsafe floating-point math optimizations are allowed
2069 ; for the sake of speed. IEEE compliance is not guaranteed, and operations
2070 ; are allowed to assume that their arguments and results are "normal"
2071 ; (e.g., nonnegative for SQRT).
2072 funsafe-math-optimizations
2073 Common Report Var(flag_unsafe_math_optimizations) Optimization SetByCombined
2074 Allow math optimizations that may violate IEEE or ISO standards
2077 Common Report Var(flag_unswitch_loops) Optimization
2078 Perform loop unswitching
2081 Common Report Var(flag_unwind_tables) Optimization
2082 Just generate unwind tables for exception handling
2087 ; Positive if we should track variables, negative if we should run
2088 ; the var-tracking pass only to discard debug annotations, zero if
2089 ; we're not to run it. When flag_var_tracking == 2 (AUTODETECT_VALUE) it
2090 ; will be set according to optimize, debug_info_level and debug_hooks
2091 ; in process_options ().
2093 Common Report Var(flag_var_tracking) Init(2) Optimization
2094 Perform variable tracking
2096 ; Positive if we should track variables at assignments, negative if
2097 ; we should run the var-tracking pass only to discard debug
2098 ; annotations. When flag_var_tracking_assignments ==
2099 ; AUTODETECT_VALUE it will be set according to flag_var_tracking.
2100 fvar-tracking-assignments
2101 Common Report Var(flag_var_tracking_assignments) Init(2) Optimization
2102 Perform variable tracking by annotating assignments
2104 ; Nonzero if we should toggle flag_var_tracking_assignments after
2105 ; processing options and computing its default. */
2106 fvar-tracking-assignments-toggle
2107 Common Report Var(flag_var_tracking_assignments_toggle) Optimization
2108 Toggle -fvar-tracking-assignments
2110 fvar-tracking-uninit
2111 Common Report Var(flag_var_tracking_uninit) Optimization
2112 Perform variable tracking and also tag variables that are uninitialized
2115 Common Report Var(flag_tree_vectorize) Optimization
2116 Enable loop vectorization on trees
2119 Common Report Var(flag_tree_slp_vectorize) Init(2) Optimization
2120 Enable basic block vectorization (SLP) on trees
2123 Common Report Var(flag_vect_cost_model) Optimization
2124 Enable use of cost model in vectorization
2126 ftree-vect-loop-version
2127 Common Report Var(flag_tree_vect_loop_version) Init(1) Optimization
2128 Enable loop versioning when doing loop vectorization on trees
2130 ftree-vectorizer-verbose=
2131 Common RejectNegative Joined UInteger
2132 -ftree-vectorizer-verbose=<number> Set the verbosity level of the vectorizer
2135 Common Report Var(flag_tree_scev_cprop) Init(1) Optimization
2136 Enable copy propagation of scalar-evolution information.
2138 ; -fverbose-asm causes extra commentary information to be produced in
2139 ; the generated assembly code (to make it more readable). This option
2140 ; is generally only of use to those who actually need to read the
2141 ; generated assembly code (perhaps while debugging the compiler itself).
2142 ; -fno-verbose-asm, the default, causes the extra information
2143 ; to not be added and is useful when comparing two assembler files.
2145 Common Report Var(flag_verbose_asm)
2146 Add extra commentary to assembler output
2149 Common Joined RejectNegative Enum(symbol_visibility) Var(default_visibility) Init(VISIBILITY_DEFAULT)
2150 -fvisibility=[default|internal|hidden|protected] Set the default symbol visibility
2153 Name(symbol_visibility) Type(enum symbol_visibility) UnknownError(unrecognized visibility value %qs)
2156 Enum(symbol_visibility) String(default) Value(VISIBILITY_DEFAULT)
2159 Enum(symbol_visibility) String(internal) Value(VISIBILITY_INTERNAL)
2162 Enum(symbol_visibility) String(hidden) Value(VISIBILITY_HIDDEN)
2165 Enum(symbol_visibility) String(protected) Value(VISIBILITY_PROTECTED)
2168 Common Report Var(flag_value_profile_transformations) Optimization
2169 Use expression value profiles in optimizations
2172 Common Report Var(flag_web) Init(2) Optimization
2173 Construct webs and split unrelated uses of single variable
2175 ftree-builtin-call-dce
2176 Common Report Var(flag_tree_builtin_call_dce) Init(0) Optimization
2177 Enable conditional dead code elimination for builtin calls
2180 Common Report Var(flag_whole_program) Init(0) Optimization
2181 Perform whole program optimizations
2184 Common Report Var(flag_wrapv) Optimization
2185 Assume signed arithmetic overflow wraps around
2187 fzero-initialized-in-bss
2188 Common Report Var(flag_zero_initialized_in_bss) Init(1)
2189 Put zero initialized data in the bss section
2192 Common JoinedOrMissing
2193 Generate debug information in default format
2196 Common JoinedOrMissing Negative(gdwarf-)
2197 Generate debug information in COFF format
2200 Common Joined UInteger Var(dwarf_version) Init(2) Negative(gstabs)
2201 Generate debug information in DWARF v2 (or later) format
2204 Common JoinedOrMissing
2205 Generate debug information in default extended format
2208 Common JoinedOrMissing Negative(gstabs+)
2209 Generate debug information in STABS format
2212 Common JoinedOrMissing Negative(gvms)
2213 Generate debug information in extended STABS format
2216 Common RejectNegative Var(dwarf_strict,0) Init(-1)
2217 Emit DWARF additions beyond selected version
2220 Common Report RejectNegative Var(dwarf_strict,1)
2221 Don't emit DWARF additions beyond selected version
2224 Common Report Var(flag_gtoggle)
2225 Toggle debug information generation
2228 Common JoinedOrMissing Negative(gxcoff)
2229 Generate debug information in VMS format
2232 Common JoinedOrMissing Negative(gxcoff+)
2233 Generate debug information in XCOFF format
2236 Common JoinedOrMissing Negative(gcoff)
2237 Generate debug information in extended XCOFF format
2240 Driver Joined Separate
2243 Common Joined Var(plugindir_string) Init(0)
2244 -iplugindir=<dir> Set <dir> to be the default plugin directory
2247 Driver Joined Separate
2252 no-canonical-prefixes
2268 Common Driver Joined Separate Var(asm_file_name) MissingArgError(missing filename after %qs)
2269 -o <file> Place output into <file>
2272 Common Var(profile_flag)
2273 Enable function profiling
2276 Driver Var(pass_exit_codes)
2279 Common Var(pedantic)
2280 Issue warnings needed for strict compliance to the standard
2283 Common Var(flag_pedantic_errors)
2284 Like -pedantic but issue them as errors
2290 Driver Var(use_pipes)
2293 Driver JoinedOrMissing Var(print_file_name)
2295 print-libgcc-file-name
2298 print-multi-directory
2299 Driver Var(print_multi_directory)
2302 Driver Var(print_multi_lib)
2304 print-multi-os-directory
2305 Driver Var(print_multi_os_directory)
2308 Driver JoinedOrMissing Var(print_prog_name)
2311 Driver Var(print_search_dirs)
2314 Driver Var(print_sysroot)
2316 print-sysroot-headers-suffix
2317 Driver Var(print_sysroot_headers_suffix)
2320 Common Var(quiet_flag) RejectDriver
2321 Do not display functions compiled or elapsed time
2339 Driver Var(report_times)
2342 Driver JoinedOrMissing
2345 Driver Joined Separate
2349 ; C option, but driver must not handle as "-u ndef".
2352 Common Driver Var(verbose_flag)
2353 Enable verbose output
2356 Common Var(version_flag) RejectDriver
2357 Display the compiler's version
2360 Common Var(inhibit_warnings)
2364 Driver Separate Var(wrapper_string)
2367 Driver Joined Separate
2370 Common RejectNegative Negative(pie)
2371 Create a shared library
2377 Driver Separate Alias(specs=)
2390 ; Documented for Fortran, but always accepted by driver.
2397 ; Documented for Go, but always accepted by driver.
2403 Common RejectNegative Negative(shared)
2404 Create a position independent executable
2407 Driver Joined Separate
2409 ; This comment is to ensure we retain the blank line above.