1 ; Options for the language- and target-independent parts of the compiler.
3 ; Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012
4 ; Free Software Foundation, Inc.
6 ; This file is part of GCC.
8 ; GCC is free software; you can redistribute it and/or modify it under
9 ; the terms of the GNU General Public License as published by the Free
10 ; Software Foundation; either version 3, or (at your option) any later
13 ; GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 ; WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 ; FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
18 ; You should have received a copy of the GNU General Public License
19 ; along with GCC; see the file COPYING3. If not see
20 ; <http://www.gnu.org/licenses/>.
22 ; See the GCC internals manual (options.texi) for a description of this file's format.
24 ; Please try to keep this file in ASCII collating order.
35 ; Not used directly to control optimizations, only to save -Ofast
36 ; setting for "optimize" attributes.
40 ; True if this is the lto front end. This is used to disable gimple
41 ; generation and lowering passes that are normally run on the output
42 ; of a front end. These passes must be bypassed for lto since they
43 ; have already been done before the gimple was written.
47 ; 0 means straightforward implementation of complex divide acceptable.
48 ; 1 means wide ranges of inputs must work for complex divide.
49 ; 2 means C99-like requirements for complex multiply and divide.
51 int flag_complex_method = 1
53 ; Nonzero if subexpressions must be evaluated from left-to-right.
55 int flag_evaluation_order = 0
57 ; Language specific warning pass for unused results.
59 bool flag_warn_unused_result = false
64 ; Nonzero if we should write GIMPLE bytecode for link-time optimization.
68 ; True to warn about any objects definitions whose size is larger
69 ; than N bytes. Also want about function definitions whose returned
70 ; values are larger than N bytes, where N is 'larger_than_size'.
75 HOST_WIDE_INT larger_than_size
77 ; True to warn about any function whose frame size is larger
80 bool warn_frame_larger_than
83 HOST_WIDE_INT frame_larger_than_size
85 ; Nonzero means we should be saving declaration info into a .X file.
87 int flag_gen_aux_info = 0
89 ; Nonzero if we are compiling code for a shared library, zero for
94 ; These two are really VEC(char_p,heap) *.
97 void *flag_instrument_functions_exclude_functions
100 void *flag_instrument_functions_exclude_files
102 ; Generic structs (e.g. templates not explicitly specialized)
103 ; may not have a compilation unit associated with them, and so
104 ; may need to be treated differently from ordinary structs.
106 ; Structs only handled by reference (indirectly), will also usually
107 ; not need as much debugging information.
110 enum debug_struct_file debug_struct_ordinary[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
113 enum debug_struct_file debug_struct_generic[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
115 ; True if we should exit after parsing options.
117 bool exit_after_options
119 ; Type(s) of debugging information we are producing (if any). See
120 ; flag-types.h for the definitions of the different possible types of
121 ; debugging information.
123 enum debug_info_type write_symbols = NO_DEBUG
125 ; Level of debugging information we are producing. See flag-types.h
126 ; for the definitions of the different possible levels.
128 enum debug_info_levels debug_info_level = DINFO_LEVEL_NONE
130 ; Nonzero means use GNU-only extensions in the generated symbolic
131 ; debugging information. Currently, this only has an effect when
132 ; write_symbols is set to DBX_DEBUG, XCOFF_DEBUG, or DWARF_DEBUG.
134 bool use_gnu_debug_info_extensions
136 ; Original value of maximum field alignment in bytes, specified via
137 ; -fpack-struct=<value>.
139 unsigned int initial_max_fld_align = TARGET_DEFAULT_PACK_STRUCT
142 enum vect_verbosity_levels user_vect_verbosity_level = MAX_VERBOSITY_LEVEL
144 ; Type of stack check.
146 enum stack_check_type flag_stack_check = NO_STACK_CHECK
148 ; True if stack usage information needs to be computed.
150 bool flag_stack_usage_info = false
152 ; -dA causes debug commentary information to be produced in
153 ; the generated assembly code (to make it more readable). This option
154 ; is generally only of use to those who actually need to read the
155 ; generated assembly code (perhaps while debugging the compiler itself).
156 ; Currently, this switch is only used by dwarf2out.c; however, it is intended
157 ; to be a catchall for printing debug information in the assembler file.
161 ; -dP causes the rtl to be emitted as a comment in assembly.
163 int flag_dump_rtl_in_asm
165 ; Whether -da was passed (used only in handle_common_deferred_options).
167 bool flag_dump_all_passed
169 ; Other flags saying which kinds of debugging dump have been requested.
172 int rtl_dump_and_exit
175 int flag_print_asm_name
178 enum graph_dump_types graph_dump_format = no_graph
180 ; Name of top-level original source file (what was input to cpp).
181 ; This comes from the #-command at the beginning of the actual input.
182 ; If there isn't any there, then this is the cc1 input file name.
184 const char *main_input_filename
186 ; Pointer to base name in main_input_filename, with directories and a
187 ; single final extension removed, and the length of this base
191 const char *main_input_basename
194 int main_input_baselength
196 ; Which options have been printed by --help.
200 ; Which enums have been printed by --help. 0 = not printed, no
201 ; relevant options seen, 1 = relevant option seen, not yet printed, 2
204 char *help_enum_printed
206 ; The number of columns for --help output.
208 unsigned int help_columns
210 ; Whether this options structure has been through finish_options
212 bool flag_opts_finished
224 Driver Alias(coverage)
230 Common Separate Alias(d)
233 Common Joined Alias(d)
236 Common Separate Alias(dumpbase)
239 Common Separate Alias(dumpdir)
242 Driver Separate Alias(e)
245 Driver Joined Alias(e)
248 Common Warning Alias(Wextra)
251 Driver Separate Alias(Xassembler)
254 Driver JoinedOrMissing Alias(Xassembler)
257 Driver Separate Alias(Xlinker)
260 Driver JoinedOrMissing Alias(Xlinker)
263 Driver Separate Alias(u)
266 Driver Joined Alias(u)
269 Common Driver Var(help_flag)
270 Display this information
273 Common Driver Report Joined
274 --help=<class> Display descriptions of a specific class of options. <class> is one or more of optimizers, target, warnings, undocumented, params
277 Driver Separate Alias(x)
280 Driver Joined Alias(x)
283 Driver Separate Alias(L)
286 Driver Joined Alias(L)
288 -no-canonical-prefixes
289 Driver Alias(no-canonical-prefixes)
291 -no-standard-libraries
292 Driver Alias(nostdlib)
301 Common Driver Separate Alias(o) MissingArgError(missing filename after %qs)
304 Common Driver Joined Alias(o) MissingArgError(missing filename after %qs)
307 Driver Alias(pass-exit-codes)
310 Common Alias(Wpedantic)
313 Common Alias(pedantic-errors)
322 Driver Separate Alias(B)
325 Driver JoinedOrMissing Alias(B)
331 Driver Separate Alias(print-file-name=)
334 Driver JoinedOrMissing Alias(print-file-name=)
336 -print-libgcc-file-name
337 Driver Alias(print-libgcc-file-name)
339 -print-multi-directory
340 Driver Alias(print-multi-directory)
343 Driver Alias(print-multi-lib)
345 -print-multi-os-directory
346 Driver Alias(print-multi-os-directory)
349 Driver Separate Alias(print-prog-name=)
352 Driver JoinedOrMissing Alias(print-prog-name=)
355 Driver Alias(print-search-dirs)
358 Driver Alias(print-sysroot)
360 -print-sysroot-headers-suffix
361 Driver Alias(print-sysroot-headers-suffix)
367 Driver Alias(save-temps)
373 Driver Separate Alias(specs=)
376 Driver Joined Alias(specs=)
382 Driver Alias(symbolic)
386 Alias for --help=target
394 ;; The driver used to convert options such as --help into forms such
395 ;; as -fhelp; the following four entries are for compatibility with
396 ;; any direct uses of those (undocumented) -f forms
398 Common Driver Alias(-help)
401 Common Driver Joined Alias(-help=)
404 Common Driver Alias(-target-help)
407 Common Driver Alias(-version)
411 --param <param>=<value> Set parameter <param> to value. See below for a complete list of parameters
414 Common Joined Alias(-param)
417 Driver Separate Alias(-sysroot=)
420 Driver JoinedOrMissing
426 Driver Joined Separate
432 Driver Joined Separate
438 Common JoinedOrMissing Optimization
439 -O<number> Set optimization level to <number>
443 Optimize for space rather than speed
447 Optimize for speed disregarding exact standards compliance
459 Driver Joined Separate
465 Driver Joined Separate
486 Common RejectNegative Warning Alias(Wextra)
487 This switch is deprecated; use -Wextra instead
490 Driver JoinedOrMissing
493 Driver JoinedOrMissing
496 Driver JoinedOrMissing
499 Common Var(warn_aggregate_return) Warning
500 Warn about returning structures, unions or arrays
503 Common Var(warn_array_bounds) Warning
504 Warn if an array is accessed out of bounds
507 Common Var(warn_attributes) Init(1) Warning
508 Warn about inappropriate attribute usage
511 Common Var(warn_cast_align) Warning
512 Warn about pointer casts which increase alignment
515 Common Var(warn_cpp) Init(1) Warning
516 Warn when a #warning directive is encountered
518 Wdeprecated-declarations
519 Common Var(warn_deprecated_decl) Init(1) Warning
520 Warn about uses of __attribute__((deprecated)) declarations
522 Wdisabled-optimization
523 Common Var(warn_disabled_optimization) Warning
524 Warn when an optimization pass is disabled
527 Common Var(warnings_are_errors)
528 Treat all warnings as errors
532 Treat specified warning as error
535 Common Var(extra_warnings) Warning
536 Print extra (possibly unwanted) warnings
539 Common Var(flag_fatal_errors)
540 Exit on the first error occurred
543 Common RejectNegative Joined UInteger
544 -Wframe-larger-than=<number> Warn if a function's stack frame requires more than <number> bytes
547 Common Var(warn_free_nonheap_object) Init(1) Warning
548 Warn when attempting to free a non-heap object
551 Common Var(warn_inline) Warning
552 Warn when an inlined function cannot be inlined
554 Winvalid-memory-model
555 Common Var(warn_invalid_memory_model) Init(1) Warning
556 Warn when an atomic memory model parameter is known to be outside the valid range.
559 Common RejectNegative Joined Warning Undocumented Alias(Wlarger-than=)
562 Common RejectNegative Joined UInteger Warning
563 -Wlarger-than=<number> Warn if an object is larger than <number> bytes
565 Wunsafe-loop-optimizations
566 Common Var(warn_unsafe_loop_optimizations) Warning
567 Warn if the loop cannot be optimized due to nontrivial assumptions.
570 Common Alias(Wsuggest-attribute=noreturn)
573 Common Var(warn_overflow) Init(1) Warning
574 Warn about overflow in arithmetic expressions
577 Common Var(warn_packed) Warning
578 Warn when the packed attribute has no effect on struct layout
581 Common Var(warn_padded) Warning
582 Warn when padding is required to align structure members
585 Common Var(pedantic) Warning
586 Issue warnings needed for strict compliance to the standard
589 Common Var(warn_shadow) Warning
590 Warn when one local variable shadows another
593 Common Var(warn_stack_protect) Warning
594 Warn when not issuing stack smashing protection for some reason
597 Common Joined RejectNegative UInteger Var(warn_stack_usage) Init(-1) Warning
598 Warn if stack usage might be larger than specified amount
602 Warn about code which might break strict aliasing rules
605 Common Joined RejectNegative UInteger Var(warn_strict_aliasing) Init(-1) Warning
606 Warn about code which might break strict aliasing rules
610 Warn about optimizations that assume that signed overflow is undefined
613 Common Joined RejectNegative UInteger Var(warn_strict_overflow) Init(-1) Warning
614 Warn about optimizations that assume that signed overflow is undefined
616 Wsuggest-attribute=const
617 Common Var(warn_suggest_attribute_const) Warning
618 Warn about functions which might be candidates for __attribute__((const))
620 Wsuggest-attribute=pure
621 Common Var(warn_suggest_attribute_pure) Warning
622 Warn about functions which might be candidates for __attribute__((pure))
624 Wsuggest-attribute=noreturn
625 Common Var(warn_suggest_attribute_noreturn) Warning
626 Warn about functions which might be candidates for __attribute__((noreturn))
629 Common Var(warn_switch) Warning
630 Warn about enumerated switches, with no default, missing a case
633 Common Var(warn_switch_default) Warning
634 Warn about enumerated switches missing a \"default:\" statement
637 Common Var(warn_switch_enum) Warning
638 Warn about all enumerated switches missing a specific case
641 Common Var(warn_system_headers) Warning
642 Do not suppress warnings from system headers
645 Common Var(warn_trampolines) Warning
646 Warn whenever a trampoline is generated
649 Common Var(warn_type_limits) Warning EnabledBy(Wextra)
650 Warn if a comparison is always true or always false due to the limited range of the data type
653 Common Var(warn_uninitialized) Warning EnabledBy(Wextra)
654 Warn about uninitialized automatic variables
657 Common Var(warn_maybe_uninitialized) Warning EnabledBy(Wuninitialized)
658 Warn about maybe uninitialized automatic variables
662 Does nothing. Preserved for backward compatibility.
665 Common Var(warn_unused) Init(0) Warning
666 Enable all -Wunused- warnings
668 Wunused-but-set-parameter
669 Common Var(warn_unused_but_set_parameter) Init(-1) Warning
670 Warn when a function parameter is only set, otherwise unused
672 Wunused-but-set-variable
673 Common Var(warn_unused_but_set_variable) Warning EnabledBy(Wunused)
674 Warn when a variable is only set, otherwise unused
677 Common Var(warn_unused_function) Warning EnabledBy(Wunused)
678 Warn when a function is unused
681 Common Var(warn_unused_label) Warning EnabledBy(Wunused)
682 Warn when a label is unused
685 Common Var(warn_unused_parameter) Init(-1) Warning
686 Warn when a function parameter is unused
689 Common Var(warn_unused_value) Warning EnabledBy(Wunused)
690 Warn when an expression value is unused
693 Common Var(warn_unused_variable) Warning EnabledBy(Wunused)
694 Warn when a variable is unused
697 Common Var(warn_coverage_mismatch) Init(1) Warning
698 Warn in case profiles in -fprofile-use do not match
700 Wvector-operation-performance
701 Common Var(warn_vector_operation_performance) Warning
702 Warn when a vector operation is compiled outside the SIMD
717 Common Separate Var(aux_info_file_name)
718 -aux-info <file> Emit declaration information into <file>
721 Common Joined Alias(aux-info)
724 Common Separate RejectDriver Var(aux_base_name)
727 Common Separate RejectDriver
737 -d<letters> Enable dumps from specific passes of the compiler
740 Common Separate Var(dump_base_name)
741 -dumpbase <file> Set the file basename to be used for dumps
744 Common Separate Var(dump_dir_name)
745 -dumpdir <dir> Set the directory name to be used for dumps
757 Driver Joined Separate
759 ; This option has historically been passed down to the linker by an
760 ; accident of a %{e*} spec, so ensure it continues to be passed down
761 ; as a single option. The supported option for this purpose is
762 ; -rdynamic. See PR 47390.
766 ; The version of the C++ ABI in use. The following values are allowed:
768 ; 0: The version of the ABI believed most conformant with the C++ ABI
769 ; specification. This ABI may change as bugs are discovered and fixed.
770 ; Therefore, 0 will not necessarily indicate the same ABI in different
773 ; 1: The version of the ABI first used in G++ 3.2.
775 ; 2: The version of the ABI first used in G++ 3.4 (and current default).
777 ; 3: The version of the ABI that fixes the missing underscore
778 ; in template non-type arguments of pointer type.
780 ; 4: The version of the ABI that introduces unambiguous mangling of
781 ; vector types. First selectable in G++ 4.5.
783 ; 5: The version of the ABI that ignores attribute const/noreturn
784 ; in function pointer mangling, and corrects mangling of decltype and
785 ; function parameters used in other parameters and the return type.
786 ; First selectable in G++ 4.6.
788 ; 6: The version of the ABI that doesn't promote scoped enums to int and
789 ; changes the mangling of template argument packs, const/static_cast,
790 ; prefix ++ and --, and a class scope function used as a template
792 ; First selectable in G++ 4.7.
794 ; 7: The version of the ABI that treats nullptr_t as a builtin type.
795 ; First selectable in G++ 4.8.
796 ; Additional positive integers will be assigned as new versions of
797 ; the ABI become the default version of the ABI.
799 Common Joined RejectNegative UInteger Var(flag_abi_version) Init(2)
802 Common Report Var(align_functions,0) Optimization UInteger
803 Align the start of functions
806 Common RejectNegative Joined UInteger Var(align_functions)
809 Common Report Var(align_jumps,0) Optimization UInteger
810 Align labels which are only reached by jumping
813 Common RejectNegative Joined UInteger Var(align_jumps)
816 Common Report Var(align_labels,0) Optimization UInteger
820 Common RejectNegative Joined UInteger Var(align_labels)
823 Common Report Var(align_loops,0) Optimization UInteger
824 Align the start of loops
827 Common RejectNegative Joined UInteger Var(align_loops)
831 Does nothing. Preserved for backward compatibility.
835 Does nothing. Preserved for backward compatibility.
837 fargument-noalias-global
839 Does nothing. Preserved for backward compatibility.
841 fargument-noalias-anything
843 Does nothing. Preserved for backward compatibility.
845 fasynchronous-unwind-tables
846 Common Report Var(flag_asynchronous_unwind_tables) Optimization
847 Generate unwind tables that are exact at each instruction boundary
850 Common Report Var(flag_auto_inc_dec) Init(1)
851 Generate auto-inc/dec instructions
853 ; -fcheck-bounds causes gcc to generate array bounds checks.
854 ; For C, C++ and ObjC: defaults off.
855 ; For Java: defaults to on.
856 ; For Fortran: defaults to off.
858 Common Report Var(flag_bounds_check)
859 Generate code to check bounds before indexing arrays
862 Common Report Var(flag_branch_on_count_reg) Init(1) Optimization
863 Replace add, compare, branch with branch on count register
865 fbranch-probabilities
866 Common Report Var(flag_branch_probabilities) Optimization
867 Use profiling information for branch probabilities
869 fbranch-target-load-optimize
870 Common Report Var(flag_branch_target_load_optimize) Optimization
871 Perform branch target load optimization before prologue / epilogue threading
873 fbranch-target-load-optimize2
874 Common Report Var(flag_branch_target_load_optimize2) Optimization
875 Perform branch target load optimization after prologue / epilogue threading
878 Common Report Var(flag_btr_bb_exclusive) Optimization
879 Restrict target load migration not to re-use registers in any basic block
882 Common Joined RejectNegative Var(common_deferred_options) Defer
883 -fcall-saved-<register> Mark <register> as being preserved across functions
886 Common Joined RejectNegative Var(common_deferred_options) Defer
887 -fcall-used-<register> Mark <register> as being corrupted by function calls
889 ; Nonzero for -fcaller-saves: allocate values in regs that need to
890 ; be saved across function calls, if that produces overall better code.
891 ; Optional now, so people can test it.
893 Common Report Var(flag_caller_saves) Optimization
894 Save registers around function calls
897 Common Report Var(flag_check_data_deps)
898 Compare the results of several data dependence analyzers.
900 fcombine-stack-adjustments
901 Common Report Var(flag_combine_stack_adjustments) Optimization
902 Looks for opportunities to reduce stack adjustments and stack references.
905 Common Report Var(flag_no_common,0) Optimization
906 Do not put uninitialized globals in the common section
910 ; Converted by the driver to -fcompare-debug= options.
913 Common Driver JoinedOrMissing RejectNegative Var(flag_compare_debug_opt)
914 -fcompare-debug[=<opts>] Compile with and without e.g. -gtoggle, and compare the final-insns dump
916 fcompare-debug-second
917 Common Driver RejectNegative Var(flag_compare_debug)
918 Run only the second compilation of -fcompare-debug
921 Common Report Var(flag_compare_elim_after_reload) Optimization
922 Perform comparison elimination after register allocation has finished
925 Common Var(flag_conserve_stack) Optimization
926 Do not perform optimizations increasing noticeably stack usage
929 Common Report Var(flag_cprop_registers) Optimization
930 Perform a register copy-propagation optimization pass
933 Common Report Var(flag_crossjumping) Optimization
934 Perform cross-jumping optimization
937 Common Report Var(flag_cse_follow_jumps) Optimization
938 When running CSE, follow jumps to their targets
942 Does nothing. Preserved for backward compatibility.
945 Common Report Var(flag_cx_limited_range) Optimization SetByCombined
946 Omit range reduction step when performing complex division
949 Common Report Var(flag_cx_fortran_rules) Optimization
950 Complex multiplication and division follow Fortran rules
953 Common Report Var(flag_data_sections) Optimization
954 Place data items into their own section
957 Common Report Var(common_deferred_options) Defer
958 List all available debugging counters with their limits and counts.
961 Common RejectNegative Joined Var(common_deferred_options) Defer
962 -fdbg-cnt=<counter>:<limit>[,<counter>:<limit>,...] Set the debug counter limit.
965 Common Joined RejectNegative Var(common_deferred_options) Defer
966 Map one directory name to another in debug information
969 Common Report Var(flag_debug_types_section) Init(0)
970 Output .debug_types section when using DWARF v4 debuginfo.
972 ; Nonzero for -fdefer-pop: don't pop args after each function call
973 ; instead save them up to pop many calls' args with one insns.
975 Common Report Var(flag_defer_pop) Optimization
976 Defer popping functions args from stack until later
979 Common Report Var(flag_delayed_branch) Optimization
980 Attempt to fill delay slots of branch instructions
982 fdelete-dead-exceptions
983 Common Report Var(flag_delete_dead_exceptions) Init(0)
984 Delete dead instructions that may throw exceptions
986 fdelete-null-pointer-checks
987 Common Report Var(flag_delete_null_pointer_checks) Init(1) Optimization
988 Delete useless null pointer checks
991 Common Report Var(flag_devirtualize) Optimization
992 Try to convert virtual calls to direct ones.
994 fdiagnostics-show-location=
995 Common Joined RejectNegative Enum(diagnostic_prefixing_rule)
996 -fdiagnostics-show-location=[once|every-line] How often to emit source location at the beginning of line-wrapped diagnostics
998 ; Required for these enum values.
1003 Name(diagnostic_prefixing_rule) Type(int)
1006 Enum(diagnostic_prefixing_rule) String(once) Value(DIAGNOSTICS_SHOW_PREFIX_ONCE)
1009 Enum(diagnostic_prefixing_rule) String(every-line) Value(DIAGNOSTICS_SHOW_PREFIX_EVERY_LINE)
1011 fdiagnostics-show-caret
1012 Common Var(flag_diagnostics_show_caret) Init(1)
1013 Show the source line with a caret indicating the column
1015 fdiagnostics-show-option
1016 Common Var(flag_diagnostics_show_option) Init(1)
1017 Amend appropriate diagnostic messages with the command line option that controls them
1020 Common Joined RejectNegative Var(common_deferred_options) Defer
1021 -fdisable-[tree|rtl|ipa]-<pass>=range1+range2 disables an optimization pass
1024 Common Joined RejectNegative Var(common_deferred_options) Defer
1025 -fenable-[tree|rtl|ipa]-<pass>=range1+range2 enables an optimization pass
1028 Common Joined RejectNegative Var(common_deferred_options) Defer
1029 -fdump-<type> Dump various compiler internals to a file
1032 Driver RejectNegative
1035 Common RejectNegative Joined Var(flag_dump_final_insns)
1036 -fdump-final-insns=filename Dump to filename the insns at the end of translation
1039 Common RejectNegative Joined Var(flag_dump_go_spec)
1040 -fdump-go-spec=filename Write all declarations to file as Go code
1043 Common Report Var(flag_dump_noaddr)
1044 Suppress output of addresses in debugging dumps
1047 Common Var(flag_dump_passes) Init(0)
1048 Dump optimization passes
1051 Common Report Var(flag_dump_unnumbered)
1052 Suppress output of instruction numbers, line number notes and addresses in debugging dumps
1054 fdump-unnumbered-links
1055 Common Report Var(flag_dump_unnumbered_links)
1056 Suppress output of previous and next insn numbers in debugging dumps
1059 Common Report Var(flag_dwarf2_cfi_asm) Init(HAVE_GAS_CFI_DIRECTIVE)
1060 Enable CFI tables via GAS assembler directives.
1063 Common Report Var(flag_early_inlining) Init(1) Optimization
1064 Perform early inlining
1066 feliminate-dwarf2-dups
1067 Common Report Var(flag_eliminate_dwarf2_dups)
1068 Perform DWARF2 duplicate elimination
1071 Common Report Var(flag_ipa_sra) Init(0) Optimization
1072 Perform interprocedural reduction of aggregates
1074 feliminate-unused-debug-symbols
1075 Common Report Var(flag_debug_only_used_symbols)
1076 Perform unused type elimination in debug info
1078 feliminate-unused-debug-types
1079 Common Report Var(flag_eliminate_unused_debug_types) Init(1)
1080 Perform unused type elimination in debug info
1082 femit-class-debug-always
1083 Common Report Var(flag_emit_class_debug_always) Init(0)
1084 Do not suppress C++ class debug information.
1087 Common Report Var(flag_exceptions) Optimization
1088 Enable exception handling
1090 fexpensive-optimizations
1091 Common Report Var(flag_expensive_optimizations) Optimization
1092 Perform a number of minor, expensive optimizations
1095 Common Joined RejectNegative Enum(excess_precision) Var(flag_excess_precision_cmdline) Init(EXCESS_PRECISION_DEFAULT)
1096 -fexcess-precision=[fast|standard] Specify handling of excess floating-point precision
1099 Name(excess_precision) Type(enum excess_precision) UnknownError(unknown excess precision style %qs)
1102 Enum(excess_precision) String(fast) Value(EXCESS_PRECISION_FAST)
1105 Enum(excess_precision) String(standard) Value(EXCESS_PRECISION_STANDARD)
1111 Common Var(flag_fat_lto_objects) Init(1)
1112 Output lto objects containing both the intermediate language and binary output.
1115 Common Report Var(flag_finite_math_only) Optimization SetByCombined
1116 Assume no NaNs or infinities are generated
1119 Common Joined RejectNegative Var(common_deferred_options) Defer
1120 -ffixed-<register> Mark <register> as being unavailable to the compiler
1123 Common Report Var(flag_float_store) Optimization
1124 Don't allocate floats and doubles in extended-precision registers
1128 Does nothing. Preserved for backward compatibility.
1131 Common Report Var(flag_forward_propagate) Optimization
1132 Perform a forward propagation pass on RTL
1135 Common Joined RejectNegative Enum(fp_contract_mode) Var(flag_fp_contract_mode) Init(FP_CONTRACT_FAST)
1136 -ffp-contract=[off|on|fast] Perform floating-point expression contraction.
1139 Name(fp_contract_mode) Type(enum fp_contract_mode) UnknownError(unknown floating point contraction style %qs)
1142 Enum(fp_contract_mode) String(off) Value(FP_CONTRACT_OFF)
1144 ; Not implemented, fall back to conservative FP_CONTRACT_OFF.
1146 Enum(fp_contract_mode) String(on) Value(FP_CONTRACT_OFF)
1149 Enum(fp_contract_mode) String(fast) Value(FP_CONTRACT_FAST)
1151 ; Nonzero means don't put addresses of constant functions in registers.
1152 ; Used for compiling the Unix kernel, where strange substitutions are
1153 ; done on the assembly output.
1155 Common Report Var(flag_no_function_cse,0)
1156 Allow function addresses to be held in registers
1159 Common Report Var(flag_function_sections)
1160 Place each function into its own section
1163 Common Report Var(flag_gcse) Optimization
1164 Perform global common subexpression elimination
1167 Common Report Var(flag_gcse_lm) Init(1) Optimization
1168 Perform enhanced load motion during global common subexpression elimination
1171 Common Report Var(flag_gcse_sm) Init(0) Optimization
1172 Perform store motion after global common subexpression elimination
1175 Common Report Var(flag_gcse_las) Init(0) Optimization
1176 Perform redundant load after store elimination in global common subexpression
1180 Common Report Var(flag_gcse_after_reload) Optimization
1181 Perform global common subexpression elimination after register allocation
1184 ; This option is not documented yet as its semantics will change.
1186 Common Report Var(flag_graphite)
1187 Enable in and out of Graphite representation
1190 Common Report Var(flag_graphite_identity) Optimization
1191 Enable Graphite Identity transformation
1193 fhoist-adjacent-loads
1194 Common Report Var(flag_hoist_adjacent_loads) Optimization
1195 Enable hoisting adjacent loads to encourage generating conditional move
1198 floop-parallelize-all
1199 Common Report Var(flag_loop_parallelize_all) Optimization
1200 Mark all loops as parallel
1203 Common Report Var(flag_loop_strip_mine) Optimization
1204 Enable Loop Strip Mining transformation
1207 Common Report Var(flag_loop_interchange) Optimization
1208 Enable Loop Interchange transformation
1211 Common Report Var(flag_loop_block) Optimization
1212 Enable Loop Blocking transformation
1215 Common Report Var(flag_tm)
1216 Enable support for GNU transactional memory
1220 Does nothing. Preserved for backward compatibility.
1223 Common Report Var(flag_loop_optimize_isl) Optimization
1224 Enable the ISL based loop nest optimizer
1226 fstrict-volatile-bitfields
1227 Common Report Var(flag_strict_volatile_bitfields) Init(-1)
1228 Force bitfield accesses to match their type width
1230 fguess-branch-probability
1231 Common Report Var(flag_guess_branch_prob) Optimization
1232 Enable guessing of branch probabilities
1234 ; Nonzero means ignore `#ident' directives. 0 means handle them.
1235 ; Generate position-independent code for executables if possible
1236 ; On SVR4 targets, it also controls whether or not to emit a
1237 ; string identifying the compiler.
1239 Common Report Var(flag_no_ident,0)
1240 Process #ident directives
1243 Common Report Var(flag_if_conversion) Optimization
1244 Perform conversion of conditional jumps to branchless equivalents
1247 Common Report Var(flag_if_conversion2) Optimization
1248 Perform conversion of conditional jumps to conditional execution
1250 ftree-loop-if-convert
1251 Common Report Var(flag_tree_loop_if_convert) Init(-1) Optimization
1252 Convert conditional jumps in innermost loops to branchless equivalents
1254 ftree-loop-if-convert-stores
1255 Common Report Var(flag_tree_loop_if_convert_stores) Optimization
1256 Also if-convert conditional jumps containing memory writes
1258 ; -finhibit-size-directive inhibits output of .size for ELF.
1259 ; This is used only for compiling crtstuff.c,
1260 ; and it may be extended to other effects
1261 ; needed for crtstuff.c on other systems.
1262 finhibit-size-directive
1263 Common Report Var(flag_inhibit_size_directive)
1264 Do not generate .size directives
1267 Common Report Var(flag_indirect_inlining)
1268 Perform indirect inlining
1270 ; General flag to enable inlining. Specifying -fno-inline will disable
1271 ; all inlining apart from always-inline functions.
1273 Common Report Var(flag_no_inline,0) Init(0)
1274 Enable inlining of function declared \"inline\", disabling disables all inlining
1276 finline-small-functions
1277 Common Report Var(flag_inline_small_functions) Optimization
1278 Integrate functions into their callers when code size is known not to grow
1281 Common Report Var(flag_inline_functions) Optimization
1282 Integrate functions not declared \"inline\" into their callers when profitable
1284 finline-functions-called-once
1285 Common Report Var(flag_inline_functions_called_once) Optimization
1286 Integrate functions only required by their single caller
1289 Common RejectNegative Joined Alias(finline-limit=)
1292 Common RejectNegative Joined UInteger
1293 -finline-limit=<number> Limit the size of inlined functions to <number>
1296 Common Report Var(flag_inline_atomics) Init(1) Optimization
1297 Inline __atomic operations when a lock free instruction sequence is available.
1299 finstrument-functions
1300 Common Report Var(flag_instrument_function_entry_exit)
1301 Instrument function entry and exit with profiling calls
1303 finstrument-functions-exclude-function-list=
1304 Common RejectNegative Joined
1305 -finstrument-functions-exclude-function-list=name,... Do not instrument listed functions
1307 finstrument-functions-exclude-file-list=
1308 Common RejectNegative Joined
1309 -finstrument-functions-exclude-file-list=filename,... Do not instrument functions listed in files
1312 Common Report Var(flag_ipa_cp) Optimization
1313 Perform Interprocedural constant propagation
1316 Common Report Var(flag_ipa_cp_clone) Optimization
1317 Perform cloning to make Interprocedural constant propagation stronger
1320 Common Report Var(flag_ipa_profile) Init(0) Optimization
1321 Perform interprocedural profile propagation
1324 Common Report Var(flag_ipa_pta) Init(0) Optimization
1325 Perform interprocedural points-to analysis
1328 Common Report Var(flag_ipa_pure_const) Init(0) Optimization
1329 Discover pure and const functions
1332 Common Report Var(flag_ipa_reference) Init(0) Optimization
1333 Discover readonly and non addressable static variables
1336 Common Report Var(flag_ipa_matrix_reorg) Optimization
1337 Perform matrix layout flattening and transposing based
1338 on profiling information.
1342 Does nothing. Preserved for backward compatibility.
1345 Common Joined RejectNegative Enum(ira_algorithm) Var(flag_ira_algorithm) Init(IRA_ALGORITHM_CB)
1346 -fira-algorithm=[CB|priority] Set the used IRA algorithm
1349 Name(ira_algorithm) Type(enum ira_algorithm) UnknownError(unknown IRA algorithm %qs)
1352 Enum(ira_algorithm) String(CB) Value(IRA_ALGORITHM_CB)
1355 Enum(ira_algorithm) String(priority) Value(IRA_ALGORITHM_PRIORITY)
1358 Common Joined RejectNegative Enum(ira_region) Var(flag_ira_region) Init(IRA_REGION_AUTODETECT)
1359 -fira-region=[one|all|mixed] Set regions for IRA
1362 Name(ira_region) Type(enum ira_region) UnknownError(unknown IRA region %qs)
1365 Enum(ira_region) String(one) Value(IRA_REGION_ONE)
1368 Enum(ira_region) String(all) Value(IRA_REGION_ALL)
1371 Enum(ira_region) String(mixed) Value(IRA_REGION_MIXED)
1374 Common Report Var(flag_ira_loop_pressure)
1375 Use IRA based register pressure calculation
1376 in RTL loop optimizations.
1378 fira-share-save-slots
1379 Common Report Var(flag_ira_share_save_slots) Init(1)
1380 Share slots for saving different hard registers.
1382 fira-share-spill-slots
1383 Common Report Var(flag_ira_share_spill_slots) Init(1)
1384 Share stack slots for spilled pseudo-registers.
1387 Common RejectNegative Joined UInteger Var(flag_ira_verbose) Init(5)
1388 -fira-verbose=<number> Control IRA's level of diagnostic messages.
1391 Common Report Var(flag_ivopts) Init(1) Optimization
1392 Optimize induction variables on trees
1395 Common Var(flag_jump_tables) Init(1) Optimization
1396 Use jump tables for sufficiently large switch statements
1398 fkeep-inline-functions
1399 Common Report Var(flag_keep_inline_functions)
1400 Generate code for functions even if they are fully inlined
1403 Common Report Var(flag_keep_static_consts) Init(1)
1404 Emit static const variables even if they are not used
1407 Common Report Var(flag_leading_underscore) Init(-1)
1408 Give external symbols a leading underscore
1412 Does nothing. Preserved for backward compatibility.
1416 Enable link-time optimization.
1419 Common RejectNegative Joined Var(flag_lto)
1420 Link-time optimization with number of parallel jobs or jobserver.
1423 Common Var(flag_lto_partition_1to1)
1424 Partition functions and vars at linktime based on object files they originate from
1426 flto-partition=balanced
1427 Common Var(flag_lto_partition_balanced)
1428 Partition functions and vars at linktime into approximately same sized buckets
1431 Common Var(flag_lto_partition_none)
1432 Disable partioning and streaming
1434 ; The initial value of -1 comes from Z_DEFAULT_COMPRESSION in zlib.h.
1435 flto-compression-level=
1436 Common Joined RejectNegative UInteger Var(flag_lto_compression_level) Init(-1)
1437 -flto-compression-level=<number> Use zlib compression level <number> for IL
1440 Common Report Var(flag_lto_report) Init(0)
1441 Report various link-time optimization statistics
1444 Common Report Var(flag_errno_math) Init(1) Optimization SetByCombined
1445 Set errno after built-in math functions
1448 Common Joined RejectNegative UInteger Var(flag_max_errors)
1449 -fmax-errors=<number> Maximum number of errors to report
1452 Common Report Var(mem_report)
1453 Report on permanent memory allocation
1455 ; This will attempt to merge constant section constants, if 1 only
1456 ; string constants and constants from constant pool, if 2 also constant
1458 fmerge-all-constants
1459 Common Report Var(flag_merge_constants,2) Init(1) Optimization
1460 Attempt to merge identical constants and constant variables
1463 Common Report Var(flag_merge_constants,1) Optimization
1464 Attempt to merge identical constants across compilation units
1466 fmerge-debug-strings
1467 Common Report Var(flag_merge_debug_strings) Init(1)
1468 Attempt to merge identical debug strings across compilation units
1471 Common RejectNegative Joined UInteger
1472 -fmessage-length=<number> Limit diagnostics to <number> characters per line. 0 suppresses line-wrapping
1475 Common Report Var(flag_modulo_sched) Optimization
1476 Perform SMS based modulo scheduling before the first scheduling pass
1478 fmodulo-sched-allow-regmoves
1479 Common Report Var(flag_modulo_sched_allow_regmoves)
1480 Perform SMS based modulo scheduling with register moves allowed
1482 fmove-loop-invariants
1483 Common Report Var(flag_move_loop_invariants) Init(1) Optimization
1484 Move loop invariant computations out of loops
1487 Common Var(flag_dce) Init(1) Optimization
1488 Use the RTL dead code elimination pass
1491 Common Var(flag_dse) Init(1) Optimization
1492 Use the RTL dead store elimination pass
1494 freschedule-modulo-scheduled-loops
1495 Common Report Var(flag_resched_modulo_sched) Optimization
1496 Enable/Disable the traditional scheduling in loops that already passed modulo scheduling
1498 fnon-call-exceptions
1499 Common Report Var(flag_non_call_exceptions) Optimization
1500 Support synchronous non-call exceptions
1503 Common Report Var(flag_omit_frame_pointer) Optimization
1504 When possible do not generate stack frames
1506 foptimize-register-move
1507 Common Report Var(flag_regmove) Optimization
1508 Do the full register move optimization pass
1510 foptimize-sibling-calls
1511 Common Report Var(flag_optimize_sibling_calls) Optimization
1512 Optimize sibling and tail recursive calls
1515 Common Report Var(flag_partial_inlining)
1516 Perform partial inlining
1519 Common Report Var(pre_ipa_mem_report)
1520 Report on memory allocation before interprocedural optimization
1522 fpost-ipa-mem-report
1523 Common Report Var(post_ipa_mem_report)
1524 Report on memory allocation before interprocedural optimization
1527 Common Report Var(flag_pack_struct) Optimization
1528 Pack structure members together without holes
1531 Common RejectNegative Joined UInteger Optimization
1532 -fpack-struct=<number> Set initial maximum structure member alignment
1535 Common Report Var(flag_pcc_struct_return,1) Init(DEFAULT_PCC_STRUCT_RETURN)
1536 Return small aggregates in memory, not registers
1539 Common Report Var(flag_peel_loops) Optimization
1540 Perform loop peeling
1543 Common Report Var(flag_no_peephole,0) Optimization
1544 Enable machine specific peephole optimizations
1547 Common Report Var(flag_peephole2) Optimization
1548 Enable an RTL peephole pass before sched2
1551 Common Report Var(flag_pic,2)
1552 Generate position-independent code if possible (large mode)
1555 Common Report Var(flag_pie,2)
1556 Generate position-independent code for executables if possible (large mode)
1559 Common Report Var(flag_pic,1)
1560 Generate position-independent code if possible (small mode)
1563 Common Report Var(flag_pie,1)
1564 Generate position-independent code for executables if possible (small mode)
1567 Common Joined RejectNegative Var(common_deferred_options) Defer
1568 Specify a plugin to load
1571 Common Joined RejectNegative Var(common_deferred_options) Defer
1572 -fplugin-arg-<name>-<key>[=<value>] Specify argument <key>=<value> for plugin <name>
1574 fpredictive-commoning
1575 Common Report Var(flag_predictive_commoning) Optimization
1576 Run predictive commoning optimization.
1578 fprefetch-loop-arrays
1579 Common Report Var(flag_prefetch_loop_arrays) Init(-1) Optimization
1580 Generate prefetch instructions, if available, for arrays in loops
1583 Common Report Var(profile_flag)
1584 Enable basic program profiling code
1587 Common Report Var(profile_arc_flag)
1588 Insert arc-based program profiling code
1591 Common Joined RejectNegative Var(profile_data_prefix)
1592 Set the top-level directory for storing the profile data.
1593 The default is 'pwd'.
1596 Common Report Var(flag_profile_correction)
1597 Enable correction of flow inconsistent profile data input
1601 Enable common options for generating profile info for profile feedback directed optimizations
1604 Common Joined RejectNegative
1605 Enable common options for generating profile info for profile feedback directed optimizations, and set -fprofile-dir=
1608 Common Var(flag_profile_use)
1609 Enable common options for performing profile feedback directed optimizations
1612 Common Joined RejectNegative
1613 Enable common options for performing profile feedback directed optimizations, and set -fprofile-dir=
1616 Common Report Var(flag_profile_values)
1617 Insert code to profile values of expressions
1620 Common Var(common_deferred_options) Defer
1623 Common Joined RejectNegative Var(common_deferred_options) Defer
1624 -frandom-seed=<string> Make compile reproducible using <string>
1626 ; This switch causes the command line that was used to create an
1627 ; object file to be recorded into the object file. The exact format
1628 ; of this recording is target and binary file format dependent.
1629 ; It is related to the -fverbose-asm switch, but that switch only
1630 ; records information in the assembler output file as comments, so
1631 ; they never reach the object file.
1632 frecord-gcc-switches
1633 Common Report Var(flag_record_gcc_switches)
1634 Record gcc command line switches in the object file.
1637 Common Report Var(flag_pcc_struct_return,0) Optimization
1638 Return small aggregates in registers
1641 Common Report Var(flag_regmove) Optimization
1642 Enables a register move optimization
1645 Common Report Var(flag_rename_registers) Init(2) Optimization
1646 Perform a register renaming optimization pass
1649 Common Report Var(flag_reorder_blocks) Optimization
1650 Reorder basic blocks to improve code placement
1652 freorder-blocks-and-partition
1653 Common Report Var(flag_reorder_blocks_and_partition) Optimization
1654 Reorder basic blocks and partition into hot and cold sections
1657 Common Report Var(flag_reorder_functions) Optimization
1658 Reorder functions to improve code placement
1660 frerun-cse-after-loop
1661 Common Report Var(flag_rerun_cse_after_loop) Optimization
1662 Add a common subexpression elimination pass after loop optimizations
1666 Does nothing. Preserved for backward compatibility.
1669 Common Report Var(flag_rounding_math) Optimization SetByCombined
1670 Disable optimizations that assume default FP rounding behavior
1673 Common Report Var(flag_schedule_interblock) Init(1) Optimization
1674 Enable scheduling across basic blocks
1677 Common Report Var(flag_sched_pressure) Init(0) Optimization
1678 Enable register pressure sensitive insn scheduling
1681 Common Report Var(flag_schedule_speculative) Init(1) Optimization
1682 Allow speculative motion of non-loads
1685 Common Report Var(flag_schedule_speculative_load) Optimization
1686 Allow speculative motion of some loads
1688 fsched-spec-load-dangerous
1689 Common Report Var(flag_schedule_speculative_load_dangerous) Optimization
1690 Allow speculative motion of more loads
1693 Common RejectNegative Joined UInteger Var(sched_verbose_param)
1694 -fsched-verbose=<number> Set the verbosity level of the scheduler
1696 fsched2-use-superblocks
1697 Common Report Var(flag_sched2_use_superblocks) Optimization
1698 If scheduling post reload, do superblock scheduling
1702 Does nothing. Preserved for backward compatibility.
1705 Common Report Var(flag_schedule_insns) Optimization
1706 Reschedule instructions before register allocation
1709 Common Report Var(flag_schedule_insns_after_reload) Optimization
1710 Reschedule instructions after register allocation
1712 ; This flag should be on when a target implements non-trivial
1713 ; scheduling hooks, maybe saving some information for its own sake.
1714 ; On IA64, for example, this is used for correct bundling.
1715 fselective-scheduling
1716 Common Report Var(flag_selective_scheduling) Optimization
1717 Schedule instructions using selective scheduling algorithm
1719 fselective-scheduling2
1720 Common Report Var(flag_selective_scheduling2) Optimization
1721 Run selective scheduling after reload
1723 fsel-sched-pipelining
1724 Common Report Var(flag_sel_sched_pipelining) Init(0) Optimization
1725 Perform software pipelining of inner loops during selective scheduling
1727 fsel-sched-pipelining-outer-loops
1728 Common Report Var(flag_sel_sched_pipelining_outer_loops) Init(0) Optimization
1729 Perform software pipelining of outer loops during selective scheduling
1731 fsel-sched-reschedule-pipelined
1732 Common Report Var(flag_sel_sched_reschedule_pipelined) Init(0) Optimization
1733 Reschedule pipelined regions without pipelining
1735 ; sched_stalled_insns means that insns can be moved prematurely from the queue
1736 ; of stalled insns into the ready list.
1737 fsched-stalled-insns
1738 Common Report Var(flag_sched_stalled_insns) Optimization UInteger
1739 Allow premature scheduling of queued insns
1741 fsched-stalled-insns=
1742 Common RejectNegative Joined UInteger
1743 -fsched-stalled-insns=<number> Set number of queued insns that can be prematurely scheduled
1745 ; sched_stalled_insns_dep controls how many recently scheduled cycles will
1746 ; be examined for a dependency on a stalled insn that is candidate for
1747 ; premature removal from the queue of stalled insns into the ready list (has
1748 ; an effect only if the flag 'sched_stalled_insns' is set).
1749 fsched-stalled-insns-dep
1750 Common Report Var(flag_sched_stalled_insns_dep,1) Init(1) Optimization UInteger
1751 Set dependence distance checking in premature scheduling of queued insns
1753 fsched-stalled-insns-dep=
1754 Common RejectNegative Joined UInteger
1755 -fsched-stalled-insns-dep=<number> Set dependence distance checking in premature scheduling of queued insns
1757 fsched-group-heuristic
1758 Common Report Var(flag_sched_group_heuristic) Init(1) Optimization
1759 Enable the group heuristic in the scheduler
1761 fsched-critical-path-heuristic
1762 Common Report Var(flag_sched_critical_path_heuristic) Init(1) Optimization
1763 Enable the critical path heuristic in the scheduler
1765 fsched-spec-insn-heuristic
1766 Common Report Var(flag_sched_spec_insn_heuristic) Init(1) Optimization
1767 Enable the speculative instruction heuristic in the scheduler
1769 fsched-rank-heuristic
1770 Common Report Var(flag_sched_rank_heuristic) Init(1) Optimization
1771 Enable the rank heuristic in the scheduler
1773 fsched-last-insn-heuristic
1774 Common Report Var(flag_sched_last_insn_heuristic) Init(1) Optimization
1775 Enable the last instruction heuristic in the scheduler
1777 fsched-dep-count-heuristic
1778 Common Report Var(flag_sched_dep_count_heuristic) Init(1) Optimization
1779 Enable the dependent count heuristic in the scheduler
1782 Common Report Var(flag_section_anchors) Optimization
1783 Access data in the same section from shared anchor points
1787 Does nothing. Preserved for backward compatibility.
1791 Does nothing. Preserved for backward compatibility.
1794 Common Report Var(flag_ree) Init(0)
1795 Turn on Redundant Extensions Elimination pass.
1798 Common Report Var(flag_show_column) Init(1)
1799 Show column numbers in diagnostics, when available. Default on
1802 Common Report Var(flag_shrink_wrap) Optimization
1803 Emit function prologues only before parts of the function that need it,
1804 rather than at the top of the function.
1807 Common Report Var(flag_signaling_nans) Optimization SetByCombined
1808 Disable optimizations observable by IEEE signaling NaNs
1811 Common Report Var(flag_signed_zeros) Init(1) Optimization SetByCombined
1812 Disable floating point optimizations that ignore the IEEE signedness of zero
1814 fsingle-precision-constant
1815 Common Report Var(flag_single_precision_constant) Optimization
1816 Convert floating point constants to single precision constants
1818 fsplit-ivs-in-unroller
1819 Common Report Var(flag_split_ivs_in_unroller) Init(1) Optimization
1820 Split lifetimes of induction variables when loops are unrolled
1823 Common Report Var(flag_split_stack) Init(-1)
1824 Generate discontiguous stack frames
1827 Common Report Var(flag_split_wide_types) Optimization
1828 Split wide types into independent registers
1830 fvariable-expansion-in-unroller
1831 Common Report Var(flag_variable_expansion_in_unroller) Optimization
1832 Apply variable expansion when loops are unrolled
1835 Common Report RejectNegative Joined
1836 -fstack-check=[no|generic|specific] Insert stack checking code into the program
1839 Common Alias(fstack-check=, specific, no)
1840 Insert stack checking code into the program. Same as -fstack-check=specific
1843 Common Var(common_deferred_options) Defer
1845 fstack-limit-register=
1846 Common RejectNegative Joined Var(common_deferred_options) Defer
1847 -fstack-limit-register=<register> Trap if the stack goes past <register>
1849 fstack-limit-symbol=
1850 Common RejectNegative Joined Var(common_deferred_options) Defer
1851 -fstack-limit-symbol=<name> Trap if the stack goes past symbol <name>
1854 Common Report Var(flag_stack_protect, 1)
1855 Use propolice as a stack protection method
1857 fstack-protector-all
1858 Common Report RejectNegative Var(flag_stack_protect, 2)
1859 Use a stack protection method for every function
1862 Common RejectNegative Var(flag_stack_usage)
1863 Output stack usage information on a per-function basis
1867 Does nothing. Preserved for backward compatibility.
1869 ; Nonzero if we should do (language-dependent) alias analysis.
1870 ; Typically, this analysis will assume that expressions of certain
1871 ; types do not alias expressions of certain other types. Only used
1872 ; if alias analysis (in general) is enabled.
1874 Common Report Var(flag_strict_aliasing) Optimization
1875 Assume strict aliasing rules apply
1878 Common Report Var(flag_strict_overflow)
1879 Treat signed overflow as undefined
1882 Common Report Var(flag_sync_libcalls) Init(1)
1883 Implement __atomic operations via libcalls to legacy __sync functions
1886 Common Report Var(flag_syntax_only)
1887 Check for syntax errors, then stop
1890 Common Report Var(flag_test_coverage)
1891 Create data files needed by \"gcov\"
1894 Common Report Var(flag_thread_jumps) Optimization
1895 Perform jump threading optimizations
1898 Common Report Var(time_report)
1899 Report the time taken by each compiler pass
1902 Common Joined RejectNegative Enum(tls_model) Var(flag_tls_default) Init(TLS_MODEL_GLOBAL_DYNAMIC)
1903 -ftls-model=[global-dynamic|local-dynamic|initial-exec|local-exec] Set the default thread-local storage code generation model
1906 Name(tls_model) Type(enum tls_model) UnknownError(unknown TLS model %qs)
1909 Enum(tls_model) String(global-dynamic) Value(TLS_MODEL_GLOBAL_DYNAMIC)
1912 Enum(tls_model) String(local-dynamic) Value(TLS_MODEL_LOCAL_DYNAMIC)
1915 Enum(tls_model) String(initial-exec) Value(TLS_MODEL_INITIAL_EXEC)
1918 Enum(tls_model) String(local-exec) Value(TLS_MODEL_LOCAL_EXEC)
1921 Common Report Var(flag_toplevel_reorder) Init(2) Optimization
1922 Reorder top level functions, variables, and asms
1925 Common Report Var(flag_tracer)
1926 Perform superblock formation via tail duplication
1928 ; Zero means that floating-point math operations cannot generate a
1929 ; (user-visible) trap. This is the case, for example, in nonstop
1930 ; IEEE 754 arithmetic.
1932 Common Report Var(flag_trapping_math) Init(1) Optimization SetByCombined
1933 Assume floating-point operations can trap
1936 Common Report Var(flag_trapv) Optimization
1937 Trap for signed overflow in addition, subtraction and multiplication
1940 Common Report Var(flag_tree_ccp) Optimization
1941 Enable SSA-CCP optimization on trees
1944 Common Report Var(flag_tree_bit_ccp) Optimization
1945 Enable SSA-BIT-CCP optimization on trees
1949 Does nothing. Preserved for backward compatibility.
1952 Common Report Var(flag_tree_ch) Optimization
1953 Enable loop header copying on trees
1955 ftree-coalesce-inlined-vars
1956 Common Report Var(flag_ssa_coalesce_vars,1) Init(2) RejectNegative Optimization
1957 Enable coalescing of copy-related user variables that are inlined
1960 Common Report Var(flag_ssa_coalesce_vars,2) Optimization
1961 Enable coalescing of all copy-related user variables
1964 Common Report Var(flag_tree_copyrename) Optimization
1965 Replace SSA temporaries with better names in copies
1968 Common Report Var(flag_tree_copy_prop) Optimization
1969 Enable copy propagation on trees
1971 ftree-store-copy-prop
1973 Does nothing. Preserved for backward compatibility.
1976 Common Report Var(flag_tree_cselim) Init(2) Optimization
1977 Transform condition stores into unconditional ones
1979 ftree-switch-conversion
1980 Common Report Var(flag_tree_switch_conversion) Optimization
1981 Perform conversions of switch initializations.
1984 Common Report Var(flag_tree_dce) Optimization
1985 Enable SSA dead code elimination optimization on trees
1987 ftree-dominator-opts
1988 Common Report Var(flag_tree_dom) Optimization
1989 Enable dominator optimizations
1992 Common Report Var(flag_tree_tail_merge) Optimization
1993 Enable tail merging on trees
1996 Common Report Var(flag_tree_dse) Optimization
1997 Enable dead store elimination
2000 Common Report Var(flag_tree_forwprop) Init(1) Optimization
2001 Enable forward propagation on trees
2004 Common Report Var(flag_tree_fre) Optimization
2005 Enable Full Redundancy Elimination (FRE) on trees
2008 Common Report Var(flag_optimize_strlen) Optimization
2009 Enable string length optimizations on trees
2011 ftree-loop-distribution
2012 Common Report Var(flag_tree_loop_distribution) Optimization
2013 Enable loop distribution on trees
2015 ftree-loop-distribute-patterns
2016 Common Report Var(flag_tree_loop_distribute_patterns) Optimization
2017 Enable loop distribution for patterns transformed into a library call
2020 Common Report Var(flag_tree_loop_im) Init(1) Optimization
2021 Enable loop invariant motion on trees
2024 Common Alias(floop-interchange)
2025 Enable loop interchange transforms. Same as -floop-interchange
2028 Common Report Var(flag_tree_loop_ivcanon) Init(1) Optimization
2029 Create canonical induction variables in loops
2032 Common Report Var(flag_tree_loop_optimize) Init(1) Optimization
2033 Enable loop optimizations on tree level
2035 ftree-parallelize-loops=
2036 Common Report Joined RejectNegative UInteger Var(flag_tree_parallelize_loops) Init(1)
2037 Enable automatic parallelization of loops
2040 Common Report Var(flag_tree_phiprop) Init(1) Optimization
2041 Enable hoisting loads from conditional pointers.
2044 Common Report Var(flag_tree_pre) Optimization
2045 Enable SSA-PRE optimization on trees
2048 Common Report Var(flag_tree_partial_pre) Optimization
2049 In SSA-PRE optimization on trees, enable partial-partial redundancy elimination
2052 Common Report Var(flag_tree_pta) Init(1) Optimization
2053 Perform function-local points-to analysis on trees.
2056 Common Report Var(flag_tree_reassoc) Init(1) Optimization
2057 Enable reassociation on tree level
2061 Does nothing. Preserved for backward compatibility.
2064 Common Report Var(flag_tree_sink) Optimization
2065 Enable SSA code sinking on trees
2068 Common Report Var(flag_tree_sra) Optimization
2069 Perform scalar replacement of aggregates
2072 Common Report Var(flag_tree_ter) Optimization
2073 Replace temporary expressions in the SSA->normal pass
2076 Common Report Var(flag_tree_live_range_split) Optimization
2077 Perform live range splitting during the SSA->normal pass
2080 Common Report Var(flag_tree_vrp) Init(0) Optimization
2081 Perform Value Range Propagation on trees
2084 Common Report Var(flag_unit_at_a_time) Init(1) Optimization
2085 Compile whole compilation unit at a time
2088 Common Report Var(flag_unroll_loops) Optimization
2089 Perform loop unrolling when iteration count is known
2092 Common Report Var(flag_unroll_all_loops) Optimization
2093 Perform loop unrolling for all loops
2095 ; Nonzero means that loop optimizer may assume that the induction variables
2096 ; that control loops do not overflow and that the loops with nontrivial
2097 ; exit condition are not infinite
2098 funsafe-loop-optimizations
2099 Common Report Var(flag_unsafe_loop_optimizations) Optimization
2100 Allow loop optimizations to assume that the loops behave in normal way
2103 Common Report Var(flag_associative_math) SetByCombined
2104 Allow optimization for floating-point arithmetic which may change the
2105 result of the operation due to rounding.
2108 Common Report Var(flag_reciprocal_math) SetByCombined
2109 Same as -fassociative-math for expressions which include division.
2111 ; Nonzero means that unsafe floating-point math optimizations are allowed
2112 ; for the sake of speed. IEEE compliance is not guaranteed, and operations
2113 ; are allowed to assume that their arguments and results are "normal"
2114 ; (e.g., nonnegative for SQRT).
2115 funsafe-math-optimizations
2116 Common Report Var(flag_unsafe_math_optimizations) Optimization SetByCombined
2117 Allow math optimizations that may violate IEEE or ISO standards
2120 Common Report Var(flag_unswitch_loops) Optimization
2121 Perform loop unswitching
2124 Common Report Var(flag_unwind_tables) Optimization
2125 Just generate unwind tables for exception handling
2130 ; Positive if we should track variables, negative if we should run
2131 ; the var-tracking pass only to discard debug annotations, zero if
2132 ; we're not to run it. When flag_var_tracking == 2 (AUTODETECT_VALUE) it
2133 ; will be set according to optimize, debug_info_level and debug_hooks
2134 ; in process_options ().
2136 Common Report Var(flag_var_tracking) Init(2) Optimization
2137 Perform variable tracking
2139 ; Positive if we should track variables at assignments, negative if
2140 ; we should run the var-tracking pass only to discard debug
2141 ; annotations. When flag_var_tracking_assignments ==
2142 ; AUTODETECT_VALUE it will be set according to flag_var_tracking.
2143 fvar-tracking-assignments
2144 Common Report Var(flag_var_tracking_assignments) Init(2) Optimization
2145 Perform variable tracking by annotating assignments
2147 ; Nonzero if we should toggle flag_var_tracking_assignments after
2148 ; processing options and computing its default. */
2149 fvar-tracking-assignments-toggle
2150 Common Report Var(flag_var_tracking_assignments_toggle) Optimization
2151 Toggle -fvar-tracking-assignments
2153 fvar-tracking-uninit
2154 Common Report Var(flag_var_tracking_uninit) Optimization
2155 Perform variable tracking and also tag variables that are uninitialized
2158 Common Report Var(flag_tree_vectorize) Optimization
2159 Enable loop vectorization on trees
2162 Common Report Var(flag_tree_slp_vectorize) Init(2) Optimization
2163 Enable basic block vectorization (SLP) on trees
2166 Common Report Var(flag_vect_cost_model) Optimization
2167 Enable use of cost model in vectorization
2169 ftree-vect-loop-version
2170 Common Report Var(flag_tree_vect_loop_version) Init(1) Optimization
2171 Enable loop versioning when doing loop vectorization on trees
2173 ftree-vectorizer-verbose=
2174 Common RejectNegative Joined UInteger
2175 -ftree-vectorizer-verbose=<number> Set the verbosity level of the vectorizer
2178 Common Report Var(flag_tree_scev_cprop) Init(1) Optimization
2179 Enable copy propagation of scalar-evolution information.
2181 ; -fverbose-asm causes extra commentary information to be produced in
2182 ; the generated assembly code (to make it more readable). This option
2183 ; is generally only of use to those who actually need to read the
2184 ; generated assembly code (perhaps while debugging the compiler itself).
2185 ; -fno-verbose-asm, the default, causes the extra information
2186 ; to not be added and is useful when comparing two assembler files.
2188 Common Report Var(flag_verbose_asm)
2189 Add extra commentary to assembler output
2192 Common Joined RejectNegative Enum(symbol_visibility) Var(default_visibility) Init(VISIBILITY_DEFAULT)
2193 -fvisibility=[default|internal|hidden|protected] Set the default symbol visibility
2196 Name(symbol_visibility) Type(enum symbol_visibility) UnknownError(unrecognized visibility value %qs)
2199 Enum(symbol_visibility) String(default) Value(VISIBILITY_DEFAULT)
2202 Enum(symbol_visibility) String(internal) Value(VISIBILITY_INTERNAL)
2205 Enum(symbol_visibility) String(hidden) Value(VISIBILITY_HIDDEN)
2208 Enum(symbol_visibility) String(protected) Value(VISIBILITY_PROTECTED)
2211 Common Report Var(flag_value_profile_transformations) Optimization
2212 Use expression value profiles in optimizations
2215 Common Report Var(flag_web) Init(2) Optimization
2216 Construct webs and split unrelated uses of single variable
2218 ftree-builtin-call-dce
2219 Common Report Var(flag_tree_builtin_call_dce) Init(0) Optimization
2220 Enable conditional dead code elimination for builtin calls
2223 Common Report Var(flag_whole_program) Init(0) Optimization
2224 Perform whole program optimizations
2227 Common Report Var(flag_wrapv) Optimization
2228 Assume signed arithmetic overflow wraps around
2230 fzero-initialized-in-bss
2231 Common Report Var(flag_zero_initialized_in_bss) Init(1)
2232 Put zero initialized data in the bss section
2235 Common JoinedOrMissing
2236 Generate debug information in default format
2239 Common JoinedOrMissing Negative(gdwarf-)
2240 Generate debug information in COFF format
2243 Common Joined UInteger Var(dwarf_version) Init(4) Negative(gstabs)
2244 Generate debug information in DWARF v2 (or later) format
2247 Common JoinedOrMissing
2248 Generate debug information in default extended format
2251 Common RejectNegative Var(debug_generate_pub_sections, 0) Init(-1)
2252 Don't generate DWARF pubnames and pubtypes sections.
2255 Common RejectNegative Var(debug_generate_pub_sections, 1)
2256 Generate DWARF pubnames and pubtypes sections.
2258 gno-record-gcc-switches
2259 Common RejectNegative Var(dwarf_record_gcc_switches,0) Init(1)
2260 Don't record gcc command line switches in DWARF DW_AT_producer.
2262 grecord-gcc-switches
2263 Common RejectNegative Var(dwarf_record_gcc_switches,1)
2264 Record gcc command line switches in DWARF DW_AT_producer.
2267 Common JoinedOrMissing Negative(gstabs+)
2268 Generate debug information in STABS format
2271 Common JoinedOrMissing Negative(gvms)
2272 Generate debug information in extended STABS format
2275 Common RejectNegative Var(dwarf_strict,0) Init(0)
2276 Emit DWARF additions beyond selected version
2279 Common Report RejectNegative Var(dwarf_strict,1)
2280 Don't emit DWARF additions beyond selected version
2283 Common Report Var(flag_gtoggle)
2284 Toggle debug information generation
2287 Common JoinedOrMissing Negative(gxcoff)
2288 Generate debug information in VMS format
2291 Common JoinedOrMissing Negative(gxcoff+)
2292 Generate debug information in XCOFF format
2295 Common JoinedOrMissing Negative(gcoff)
2296 Generate debug information in extended XCOFF format
2299 Driver Joined Separate
2302 Common Joined Var(plugindir_string) Init(0)
2303 -iplugindir=<dir> Set <dir> to be the default plugin directory
2306 Driver Joined Separate
2311 no-canonical-prefixes
2324 Common Driver Joined Separate Var(asm_file_name) MissingArgError(missing filename after %qs)
2325 -o <file> Place output into <file>
2328 Common Var(profile_flag)
2329 Enable function profiling
2332 Driver Var(pass_exit_codes)
2335 Common Alias(Wpedantic)
2338 Common Var(flag_pedantic_errors)
2339 Like -pedantic but issue them as errors
2345 Driver Var(use_pipes)
2348 Driver JoinedOrMissing Var(print_file_name)
2350 print-libgcc-file-name
2353 print-multi-directory
2354 Driver Var(print_multi_directory)
2357 Driver Var(print_multi_lib)
2359 print-multi-os-directory
2360 Driver Var(print_multi_os_directory)
2363 Driver JoinedOrMissing Var(print_prog_name)
2366 Driver Var(print_search_dirs)
2369 Driver Var(print_sysroot)
2371 print-sysroot-headers-suffix
2372 Driver Var(print_sysroot_headers_suffix)
2375 Common Var(quiet_flag) RejectDriver
2376 Do not display functions compiled or elapsed time
2394 Driver Var(report_times)
2397 Driver JoinedOrMissing
2400 Driver Joined Separate
2404 ; C option, but driver must not handle as "-u ndef".
2407 Common Driver Var(verbose_flag)
2408 Enable verbose output
2411 Common Var(version_flag) RejectDriver
2412 Display the compiler's version
2415 Common Var(inhibit_warnings)
2419 Driver Separate Var(wrapper_string)
2422 Driver Joined Separate
2425 Driver RejectNegative Negative(pie)
2426 Create a shared library
2432 Driver Separate Alias(specs=)
2445 ; Documented for Fortran, but always accepted by driver.
2452 ; Documented for Go, but always accepted by driver.
2458 Driver RejectNegative Negative(shared)
2459 Create a position independent executable
2462 Driver Joined Separate
2464 ; This comment is to ensure we retain the blank line above.