1 ; Options for the language- and target-independent parts of the compiler.
3 ; Copyright (C) 2003-2016 Free Software Foundation, Inc.
5 ; This file is part of GCC.
7 ; GCC is free software; you can redistribute it and/or modify it under
8 ; the terms of the GNU General Public License as published by the Free
9 ; Software Foundation; either version 3, or (at your option) any later
12 ; GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 ; WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 ; FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 ; You should have received a copy of the GNU General Public License
18 ; along with GCC; see the file COPYING3. If not see
19 ; <http://www.gnu.org/licenses/>.
21 ; See the GCC internals manual (options.texi) for a description of this file's format.
23 ; Please try to keep this file in ASCII collating order.
37 ; Not used directly to control optimizations, only to save -Ofast
38 ; setting for "optimize" attributes.
42 ; True if this is the lto front end. This is used to disable gimple
43 ; generation and lowering passes that are normally run on the output
44 ; of a front end. These passes must be bypassed for lto since they
45 ; have already been done before the gimple was written.
49 ; This variable is set to non-0 only by LTO front-end. 1 indicates that
50 ; the output produced will be used for incrmeental linking (thus weak symbols
51 ; can still be bound).
53 int flag_incremental_link = 0
55 ; 0 means straightforward implementation of complex divide acceptable.
56 ; 1 means wide ranges of inputs must work for complex divide.
57 ; 2 means C99-like requirements for complex multiply and divide.
59 int flag_complex_method = 1
61 ; Nonzero if subexpressions must be evaluated from left-to-right.
63 int flag_evaluation_order = 0
65 ; Language specific warning pass for unused results.
67 bool flag_warn_unused_result = false
72 ; Nonzero if we should write GIMPLE bytecode for link-time optimization.
76 ; Nonzero if we should write GIMPLE bytecode for offload compilation.
78 int flag_generate_offload = 0
80 ; True to warn about any objects definitions whose size is larger
81 ; than N bytes. Also want about function definitions whose returned
82 ; values are larger than N bytes, where N is 'larger_than_size'.
87 HOST_WIDE_INT larger_than_size
89 ; True to warn about any function whose frame size is larger
92 bool warn_frame_larger_than
95 HOST_WIDE_INT frame_larger_than_size
97 ; Nonzero means we should be saving declaration info into a .X file.
99 int flag_gen_aux_info = 0
101 ; Nonzero if we are compiling code for a shared library, zero for
106 ; These two are really VEC(char_p,heap) *.
109 void *flag_instrument_functions_exclude_functions
112 void *flag_instrument_functions_exclude_files
114 ; Generic structs (e.g. templates not explicitly specialized)
115 ; may not have a compilation unit associated with them, and so
116 ; may need to be treated differently from ordinary structs.
118 ; Structs only handled by reference (indirectly), will also usually
119 ; not need as much debugging information.
122 enum debug_struct_file debug_struct_ordinary[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
125 enum debug_struct_file debug_struct_generic[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
127 ; True if we should exit after parsing options.
129 bool exit_after_options
131 ; Type(s) of debugging information we are producing (if any). See
132 ; flag-types.h for the definitions of the different possible types of
133 ; debugging information.
135 enum debug_info_type write_symbols = NO_DEBUG
137 ; Level of debugging information we are producing. See flag-types.h
138 ; for the definitions of the different possible levels.
140 enum debug_info_levels debug_info_level = DINFO_LEVEL_NONE
142 ; Nonzero means use GNU-only extensions in the generated symbolic
143 ; debugging information. Currently, this only has an effect when
144 ; write_symbols is set to DBX_DEBUG, XCOFF_DEBUG, or DWARF_DEBUG.
146 bool use_gnu_debug_info_extensions
148 ; Original value of maximum field alignment in bytes, specified via
149 ; -fpack-struct=<value>.
151 unsigned int initial_max_fld_align = TARGET_DEFAULT_PACK_STRUCT
153 ; Type of stack check.
155 enum stack_check_type flag_stack_check = NO_STACK_CHECK
157 ; True if stack usage information needs to be computed.
159 bool flag_stack_usage_info = false
161 ; -dA causes debug commentary information to be produced in
162 ; the generated assembly code (to make it more readable). This option
163 ; is generally only of use to those who actually need to read the
164 ; generated assembly code (perhaps while debugging the compiler itself).
165 ; Currently, this switch is only used by dwarf2out.c; however, it is intended
166 ; to be a catchall for printing debug information in the assembler file.
171 ; Balance between GNAT encodings and standard DWARF to emit.
173 enum dwarf_gnat_encodings gnat_encodings = DWARF_GNAT_ENCODINGS_DEFAULT
175 ; -dP causes the rtl to be emitted as a comment in assembly.
177 int flag_dump_rtl_in_asm
179 ; Whether -da was passed (used only in handle_common_deferred_options).
181 bool flag_dump_all_passed
183 ; Other flags saying which kinds of debugging dump have been requested.
186 int rtl_dump_and_exit
189 int flag_print_asm_name
191 ; Name of top-level original source file (what was input to cpp).
192 ; This comes from the #-command at the beginning of the actual input.
193 ; If there isn't any there, then this is the cc1 input file name.
195 const char *main_input_filename
197 ; Pointer to base name in main_input_filename, with directories and a
198 ; single final extension removed, and the length of this base
202 const char *main_input_basename
205 int main_input_baselength
207 ; Which options have been printed by --help.
211 ; Which enums have been printed by --help. 0 = not printed, no
212 ; relevant options seen, 1 = relevant option seen, not yet printed, 2
215 char *help_enum_printed
217 ; The number of columns for --help output.
219 unsigned int help_columns
221 ; Whether this options structure has been through finish_options
223 bool flag_opts_finished
225 ; What the sanitizer should instrument
227 unsigned int flag_sanitize
229 ; What sanitizers should recover from errors
231 unsigned int flag_sanitize_recover = SANITIZE_UNDEFINED | SANITIZE_NONDEFAULT | SANITIZE_KERNEL_ADDRESS
233 fsanitize-coverage=trace-pc
234 Common Report Var(flag_sanitize_coverage)
235 Enable coverage-guided fuzzing code instrumentation.
236 Inserts call to __sanitizer_cov_trace_pc into every basic block.
238 ; Flag whether a prefix has been added to dump_base_name
240 bool dump_base_name_prefixed = false
242 ; Flag whether HSA generation has been explicitely disabled
244 bool flag_disable_hsa = false
256 Driver Alias(coverage)
262 Common Separate Alias(d)
265 Common Joined Alias(d)
268 Common Separate Alias(dumpbase)
271 Common Separate Alias(dumpdir)
274 Driver Separate Alias(e)
277 Driver Joined Alias(e)
280 Common Warning Alias(Wextra)
283 Driver Separate Alias(Xassembler)
286 Driver JoinedOrMissing Alias(Xassembler)
289 Driver Separate Alias(Xlinker)
292 Driver JoinedOrMissing Alias(Xlinker)
295 Driver Separate Alias(u)
298 Driver Joined Alias(u)
301 Common Driver Var(help_flag)
302 Display this information.
305 Common Driver Report Joined
306 --help=<class> Display descriptions of a specific class of options. <class> is one or more of optimizers, target, warnings, undocumented, params.
309 Driver Separate Alias(x)
312 Driver Joined Alias(x)
315 Driver Separate Alias(L)
318 Driver Joined Alias(L)
320 -no-canonical-prefixes
321 Driver Alias(no-canonical-prefixes)
323 -no-standard-libraries
324 Driver Alias(nostdlib)
327 Driver Var(no_sysroot_suffix)
336 Common Driver Separate Alias(o) MissingArgError(missing filename after %qs)
339 Common Driver Joined Alias(o) MissingArgError(missing filename after %qs)
342 Driver Alias(pass-exit-codes)
345 Common Alias(Wpedantic)
348 Common Alias(pedantic-errors)
357 Driver Separate Alias(B)
360 Driver JoinedOrMissing Alias(B)
366 Driver Separate Alias(print-file-name=)
369 Driver JoinedOrMissing Alias(print-file-name=)
371 -print-libgcc-file-name
372 Driver Alias(print-libgcc-file-name)
374 -print-multi-directory
375 Driver Alias(print-multi-directory)
378 Driver Alias(print-multi-lib)
380 -print-multi-os-directory
381 Driver Alias(print-multi-os-directory)
384 Driver Alias(print-multiarch)
387 Driver Separate Alias(print-prog-name=)
390 Driver JoinedOrMissing Alias(print-prog-name=)
393 Driver Alias(print-search-dirs)
396 Driver Alias(print-sysroot)
398 -print-sysroot-headers-suffix
399 Driver Alias(print-sysroot-headers-suffix)
405 Driver Alias(save-temps)
411 Driver Separate Alias(specs=)
414 Driver Joined Alias(specs=)
420 Driver Alias(symbolic)
424 Alias for --help=target.
432 ;; The driver used to convert options such as --help into forms such
433 ;; as -fhelp; the following four entries are for compatibility with
434 ;; any direct uses of those (undocumented) -f forms
436 Common Driver Alias(-help)
439 Common Driver Joined Alias(-help=)
442 Common Driver Alias(-target-help)
445 Common Driver Alias(-version)
449 --param <param>=<value> Set parameter <param> to value. See below for a complete list of parameters.
452 Common Joined Alias(-param)
455 Driver Separate Alias(-sysroot=)
458 Driver JoinedOrMissing
464 Driver Joined Separate
470 Driver Joined Separate
476 Common JoinedOrMissing Optimization
477 -O<number> Set optimization level to <number>.
481 Optimize for space rather than speed.
485 Optimize for speed disregarding exact standards compliance.
489 Optimize for debugging experience rather than speed or size.
501 Driver Joined Separate
507 Driver Joined Separate
528 Common RejectNegative Warning Alias(Wextra)
529 This switch is deprecated; use -Wextra instead.
532 Driver JoinedOrMissing
535 Driver JoinedOrMissing
538 Driver JoinedOrMissing
541 Common Var(warn_aggregate_return) Warning
542 Warn about returning structures, unions or arrays.
544 Waggressive-loop-optimizations
545 Common Var(warn_aggressive_loop_optimizations) Init(1) Warning
546 Warn if a loop with constant number of iterations triggers undefined behavior.
549 Common Var(warn_array_bounds) Warning
550 Warn if an array is accessed out of bounds.
553 Common Joined RejectNegative UInteger Var(warn_array_bounds) Warning
554 Warn if an array is accessed out of bounds.
557 Common Var(warn_attributes) Init(1) Warning
558 Warn about inappropriate attribute usage.
561 Common Var(warn_cast_align) Warning
562 Warn about pointer casts which increase alignment.
565 Common Var(warn_cpp) Init(1) Warning
566 Warn when a #warning directive is encountered.
568 Wdeprecated-declarations
569 Common Var(warn_deprecated_decl) Init(1) Warning
570 Warn about uses of __attribute__((deprecated)) declarations.
572 Wdisabled-optimization
573 Common Var(warn_disabled_optimization) Warning
574 Warn when an optimization pass is disabled.
577 Common Var(warnings_are_errors)
578 Treat all warnings as errors.
582 Treat specified warning as error.
585 Common Var(extra_warnings) Warning
586 Print extra (possibly unwanted) warnings.
589 Common Var(flag_fatal_errors)
590 Exit on the first error occurred.
593 Common RejectNegative Joined UInteger Warning
594 -Wframe-larger-than=<number> Warn if a function's stack frame requires more than <number> bytes.
597 Common Var(warn_free_nonheap_object) Init(1) Warning
598 Warn when attempting to free a non-heap object.
601 Common Var(warn_hsa) Init(1) Warning
602 Warn when a function cannot be expanded to HSAIL.
605 Common Var(warn_inline) Warning
606 Warn when an inlined function cannot be inlined.
608 Winvalid-memory-model
609 Common Var(warn_invalid_memory_model) Init(1) Warning
610 Warn when an atomic memory model parameter is known to be outside the valid range.
613 Common RejectNegative Joined Warning Undocumented Alias(Wlarger-than=)
616 Common RejectNegative Joined UInteger Warning
617 -Wlarger-than=<number> Warn if an object is larger than <number> bytes.
620 Var(warn_nonnull_compare) Warning
621 Warn if comparing pointer parameter with nonnull attribute with NULL.
624 Common Var(warn_null_dereference) Warning
625 Warn if dereferencing a NULL pointer may lead to erroneous or undefined behavior.
627 Wunsafe-loop-optimizations
628 Common Var(warn_unsafe_loop_optimizations) Warning
629 Warn if the loop cannot be optimized due to nontrivial assumptions.
632 Common Warning Alias(Wsuggest-attribute=noreturn)
635 Common Var(warn_odr_violations) Init(1) Warning
636 Warn about some C++ One Definition Rule violations during link time optimization.
639 Common Var(warn_overflow) Init(1) Warning
640 Warn about overflow in arithmetic expressions.
643 Common Var(warn_lto_type_mismatch) Init(1) Warning
644 During link time optimization warn about mismatched types of global declarations.
647 Common Var(warn_packed) Warning
648 Warn when the packed attribute has no effect on struct layout.
651 Common Var(warn_padded) Warning
652 Warn when padding is required to align structure members.
655 Common Var(pedantic) Init(0) Warning
656 Issue warnings needed for strict compliance to the standard.
659 Common Var(warn_return_local_addr) Init(1) Warning
660 Warn about returning a pointer/reference to a local or temporary variable.
663 Common Var(warn_shadow) Warning
664 Warn when one local variable shadows another.
667 Common Var(warn_stack_protect) Warning
668 Warn when not issuing stack smashing protection for some reason.
671 Common Joined RejectNegative UInteger Var(warn_stack_usage) Init(-1) Warning
672 Warn if stack usage might be larger than specified amount.
676 Warn about code which might break strict aliasing rules.
679 Common Joined RejectNegative UInteger Var(warn_strict_aliasing) Warning
680 Warn about code which might break strict aliasing rules.
684 Warn about optimizations that assume that signed overflow is undefined.
687 Common Joined RejectNegative UInteger Var(warn_strict_overflow) Warning
688 Warn about optimizations that assume that signed overflow is undefined.
690 Wsuggest-attribute=const
691 Common Var(warn_suggest_attribute_const) Warning
692 Warn about functions which might be candidates for __attribute__((const)).
694 Wsuggest-attribute=pure
695 Common Var(warn_suggest_attribute_pure) Warning
696 Warn about functions which might be candidates for __attribute__((pure)).
698 Wsuggest-attribute=noreturn
699 Common Var(warn_suggest_attribute_noreturn) Warning
700 Warn about functions which might be candidates for __attribute__((noreturn)).
703 Common Var(warn_suggest_final_types) Warning
704 Warn about C++ polymorphic types where adding final keyword would improve code quality.
706 Wsuggest-final-methods
707 Common Var(warn_suggest_final_methods) Warning
708 Warn about C++ virtual methods where adding final keyword would improve code quality.
711 Common Var(warn_system_headers) Warning
712 Do not suppress warnings from system headers.
715 Common Var(warn_trampolines) Warning
716 Warn whenever a trampoline is generated.
719 Common Var(warn_type_limits) Warning EnabledBy(Wextra)
720 Warn if a comparison is always true or always false due to the limited range of the data type.
723 Common Var(warn_uninitialized) Warning EnabledBy(Wextra)
724 Warn about uninitialized automatic variables.
727 Common Var(warn_maybe_uninitialized) Warning EnabledBy(Wuninitialized)
728 Warn about maybe uninitialized automatic variables.
732 Does nothing. Preserved for backward compatibility.
735 Common Var(warn_unused) Init(0) Warning
736 Enable all -Wunused- warnings.
738 Wunused-but-set-parameter
739 Common Var(warn_unused_but_set_parameter) Warning EnabledBy(Wunused && Wextra)
740 Warn when a function parameter is only set, otherwise unused.
742 Wunused-but-set-variable
743 Common Var(warn_unused_but_set_variable) Warning EnabledBy(Wunused)
744 Warn when a variable is only set, otherwise unused.
747 Common Var(warn_unused_function) Warning EnabledBy(Wunused)
748 Warn when a function is unused.
751 Common Var(warn_unused_label) Warning EnabledBy(Wunused)
752 Warn when a label is unused.
755 Common Var(warn_unused_parameter) Warning EnabledBy(Wunused && Wextra)
756 Warn when a function parameter is unused.
759 Common Var(warn_unused_value) Warning EnabledBy(Wunused)
760 Warn when an expression value is unused.
763 Common Var(warn_unused_variable) Warning EnabledBy(Wunused)
764 Warn when a variable is unused.
767 Common Var(warn_coverage_mismatch) Init(1) Warning
768 Warn in case profiles in -fprofile-use do not match.
770 Wvector-operation-performance
771 Common Var(warn_vector_operation_performance) Warning
772 Warn when a vector operation is compiled outside the SIMD.
787 Common Separate Var(aux_info_file_name)
788 -aux-info <file> Emit declaration information into <file>.
791 Common Joined Alias(aux-info)
794 Common Separate RejectDriver Var(aux_base_name)
797 Common Separate RejectDriver
807 -d<letters> Enable dumps from specific passes of the compiler.
810 Common Separate Var(dump_base_name)
811 -dumpbase <file> Set the file basename to be used for dumps.
814 Common Separate Var(dump_dir_name)
815 -dumpdir <dir> Set the directory name to be used for dumps.
827 Driver Joined Separate
829 ; This option has historically been passed down to the linker by an
830 ; accident of a %{e*} spec, so ensure it continues to be passed down
831 ; as a single option. The supported option for this purpose is
832 ; -rdynamic. See PR 47390.
836 ; The version of the C++ ABI in use. The following values are allowed:
838 ; 0: The version of the ABI believed most conformant with the C++ ABI
839 ; specification. This ABI may change as bugs are discovered and fixed.
840 ; Therefore, 0 will not necessarily indicate the same ABI in different
843 ; 1: The version of the ABI first used in G++ 3.2. No longer selectable.
845 ; 2: The version of the ABI first used in G++ 3.4, and the default
848 ; 3: The version of the ABI that fixes the missing underscore
849 ; in template non-type arguments of pointer type.
851 ; 4: The version of the ABI that introduces unambiguous mangling of
852 ; vector types. First selectable in G++ 4.5.
854 ; 5: The version of the ABI that ignores attribute const/noreturn
855 ; in function pointer mangling, and corrects mangling of decltype and
856 ; function parameters used in other parameters and the return type.
857 ; First selectable in G++ 4.6.
859 ; 6: The version of the ABI that doesn't promote scoped enums to int and
860 ; changes the mangling of template argument packs, const/static_cast,
861 ; prefix ++ and --, and a class scope function used as a template
863 ; First selectable in G++ 4.7.
865 ; 7: The version of the ABI that treats nullptr_t as a builtin type and
866 ; corrects the mangling of lambdas in default argument scope.
867 ; First selectable in G++ 4.8.
869 ; 8: The version of the ABI that corrects the substitution behavior of
870 ; function types with function-cv-qualifiers.
871 ; First selectable in G++ 4.9 and default in G++ 5.
873 ; 9: The version of the ABI that corrects the alignment of nullptr_t.
874 ; First selectable and default in G++ 5.2.
876 ; 10: The version of the ABI that mangles attributes that affect type
877 ; identity, such as ia32 calling convention attributes (stdcall, etc.)
878 ; Default in G++ 6 (set in c_common_post_options).
880 ; Additional positive integers will be assigned as new versions of
881 ; the ABI become the default version of the ABI.
883 Common Joined RejectNegative UInteger Var(flag_abi_version) Init(0)
884 The version of the C++ ABI in use.
886 faggressive-loop-optimizations
887 Common Report Var(flag_aggressive_loop_optimizations) Optimization Init(1)
888 Aggressively optimize loops using language constraints.
891 Common Report Var(align_functions,0) Optimization UInteger
892 Align the start of functions.
895 Common RejectNegative Joined UInteger Var(align_functions)
898 Common Report Var(align_jumps,0) Optimization UInteger
899 Align labels which are only reached by jumping.
902 Common RejectNegative Joined UInteger Var(align_jumps)
905 Common Report Var(align_labels,0) Optimization UInteger
909 Common RejectNegative Joined UInteger Var(align_labels)
912 Common Report Var(align_loops,0) Optimization UInteger
913 Align the start of loops.
916 Common RejectNegative Joined UInteger Var(align_loops)
920 Does nothing. Preserved for backward compatibility.
924 Does nothing. Preserved for backward compatibility.
926 fargument-noalias-global
928 Does nothing. Preserved for backward compatibility.
930 fargument-noalias-anything
932 Does nothing. Preserved for backward compatibility.
935 Common Driver Report Joined
936 Select what to sanitize.
939 Common Joined RejectNegative Var(common_deferred_options) Defer
940 -fasan-shadow-offset=<number> Use custom shadow memory offset.
943 Common Joined RejectNegative Var(common_deferred_options) Defer
944 -fsanitize-sections=<sec1,sec2,...> Sanitize global variables
945 in user-defined sections.
949 After diagnosing undefined behavior attempt to continue execution.
953 This switch is deprecated; use -fsanitize-recover= instead.
955 fsanitize-undefined-trap-on-error
956 Common Driver Report Var(flag_sanitize_undefined_trap_on_error) Init(0)
957 Use trap instead of a library function for undefined behavior sanitization.
959 fasynchronous-unwind-tables
960 Common Report Var(flag_asynchronous_unwind_tables) Optimization
961 Generate unwind tables that are exact at each instruction boundary.
964 Common Report Var(flag_auto_inc_dec) Init(1) Optimization
965 Generate auto-inc/dec instructions.
968 Common Report Var(flag_auto_profile)
969 Use sample profile information for call graph node weights. The default
970 profile file is fbdata.afdo in 'pwd'.
973 Common Joined RejectNegative Var(auto_profile_file)
974 Use sample profile information for call graph node weights. The profile
975 file is specified in the argument.
977 ; -fcheck-bounds causes gcc to generate array bounds checks.
978 ; For C, C++ and ObjC: defaults off.
979 ; For Java: defaults to on.
980 ; For Fortran: defaults to off.
982 Common Report Var(flag_bounds_check)
983 Generate code to check bounds before indexing arrays.
986 Common Report Var(flag_branch_on_count_reg) Optimization
987 Replace add, compare, branch with branch on count register.
989 fbranch-probabilities
990 Common Report Var(flag_branch_probabilities) Optimization
991 Use profiling information for branch probabilities.
993 fbranch-target-load-optimize
994 Common Report Var(flag_branch_target_load_optimize) Optimization
995 Perform branch target load optimization before prologue / epilogue threading.
997 fbranch-target-load-optimize2
998 Common Report Var(flag_branch_target_load_optimize2) Optimization
999 Perform branch target load optimization after prologue / epilogue threading.
1002 Common Report Var(flag_btr_bb_exclusive) Optimization
1003 Restrict target load migration not to re-use registers in any basic block.
1006 Common Joined RejectNegative Var(common_deferred_options) Defer
1007 -fcall-saved-<register> Mark <register> as being preserved across functions.
1010 Common Joined RejectNegative Var(common_deferred_options) Defer
1011 -fcall-used-<register> Mark <register> as being corrupted by function calls.
1013 ; Nonzero for -fcaller-saves: allocate values in regs that need to
1014 ; be saved across function calls, if that produces overall better code.
1015 ; Optional now, so people can test it.
1017 Common Report Var(flag_caller_saves) Optimization
1018 Save registers around function calls.
1021 Common Report Var(flag_check_data_deps)
1022 This switch is deprecated; do not use.
1025 Common Var(flag_check_new)
1026 Check the return value of new in C++.
1029 Common Var(flag_checking) Init(CHECKING_P)
1030 Perform internal consistency checkings.
1032 fcombine-stack-adjustments
1033 Common Report Var(flag_combine_stack_adjustments) Optimization
1034 Looks for opportunities to reduce stack adjustments and stack references.
1037 Common Report Var(flag_no_common,0)
1038 Do not put uninitialized globals in the common section.
1042 ; Converted by the driver to -fcompare-debug= options.
1045 Common Driver JoinedOrMissing RejectNegative Var(flag_compare_debug_opt)
1046 -fcompare-debug[=<opts>] Compile with and without e.g. -gtoggle, and compare the final-insns dump.
1048 fcompare-debug-second
1049 Common Driver RejectNegative Var(flag_compare_debug)
1050 Run only the second compilation of -fcompare-debug.
1053 Common Report Var(flag_compare_elim_after_reload) Optimization
1054 Perform comparison elimination after register allocation has finished.
1057 Common Var(flag_conserve_stack) Optimization
1058 Do not perform optimizations increasing noticeably stack usage.
1061 Common Report Var(flag_cprop_registers) Optimization
1062 Perform a register copy-propagation optimization pass.
1065 Common Report Var(flag_crossjumping) Optimization
1066 Perform cross-jumping optimization.
1069 Common Report Var(flag_cse_follow_jumps) Optimization
1070 When running CSE, follow jumps to their targets.
1074 Does nothing. Preserved for backward compatibility.
1077 Common Report Var(flag_cx_limited_range) Optimization SetByCombined
1078 Omit range reduction step when performing complex division.
1081 Common Report Var(flag_cx_fortran_rules) Optimization
1082 Complex multiplication and division follow Fortran rules.
1085 Common Report Var(flag_data_sections)
1086 Place data items into their own section.
1089 Common Report Var(common_deferred_options) Defer
1090 List all available debugging counters with their limits and counts.
1093 Common RejectNegative Joined Var(common_deferred_options) Defer
1094 -fdbg-cnt=<counter>:<limit>[,<counter>:<limit>,...] Set the debug counter limit.
1097 Common Joined RejectNegative Var(common_deferred_options) Defer
1098 Map one directory name to another in debug information.
1100 fdebug-types-section
1101 Common Report Var(flag_debug_types_section) Init(0)
1102 Output .debug_types section when using DWARF v4 debuginfo.
1104 ; Nonzero for -fdefer-pop: don't pop args after each function call
1105 ; instead save them up to pop many calls' args with one insns.
1107 Common Report Var(flag_defer_pop) Optimization
1108 Defer popping functions args from stack until later.
1111 Common Report Var(flag_delayed_branch) Optimization
1112 Attempt to fill delay slots of branch instructions.
1114 fdelete-dead-exceptions
1115 Common Report Var(flag_delete_dead_exceptions) Init(0) Optimization
1116 Delete dead instructions that may throw exceptions.
1118 fdelete-null-pointer-checks
1119 Common Report Var(flag_delete_null_pointer_checks) Init(-1) Optimization
1120 Delete useless null pointer checks.
1122 fdevirtualize-at-ltrans
1123 Common Report Var(flag_ltrans_devirtualize)
1124 Stream extra data to support more aggressive devirtualization in LTO local transformation mode.
1126 fdevirtualize-speculatively
1127 Common Report Var(flag_devirtualize_speculatively) Optimization
1128 Perform speculative devirtualization.
1131 Common Report Var(flag_devirtualize) Optimization
1132 Try to convert virtual calls to direct ones.
1134 fdiagnostics-show-location=
1135 Common Joined RejectNegative Enum(diagnostic_prefixing_rule)
1136 -fdiagnostics-show-location=[once|every-line] How often to emit source location at the beginning of line-wrapped diagnostics.
1138 ; Required for these enum values.
1143 Name(diagnostic_prefixing_rule) Type(int)
1146 Enum(diagnostic_prefixing_rule) String(once) Value(DIAGNOSTICS_SHOW_PREFIX_ONCE)
1149 Enum(diagnostic_prefixing_rule) String(every-line) Value(DIAGNOSTICS_SHOW_PREFIX_EVERY_LINE)
1151 fdiagnostics-show-caret
1152 Common Var(flag_diagnostics_show_caret) Init(1)
1153 Show the source line with a caret indicating the column.
1156 Common Alias(fdiagnostics-color=,always,never)
1160 Driver Common Joined RejectNegative Var(flag_diagnostics_show_color) Enum(diagnostic_color_rule) Init(DIAGNOSTICS_COLOR_NO)
1161 -fdiagnostics-color=[never|always|auto] Colorize diagnostics.
1163 ; Required for these enum values.
1168 Name(diagnostic_color_rule) Type(int)
1171 Enum(diagnostic_color_rule) String(never) Value(DIAGNOSTICS_COLOR_NO)
1174 Enum(diagnostic_color_rule) String(always) Value(DIAGNOSTICS_COLOR_YES)
1177 Enum(diagnostic_color_rule) String(auto) Value(DIAGNOSTICS_COLOR_AUTO)
1179 fdiagnostics-show-option
1180 Common Var(flag_diagnostics_show_option) Init(1)
1181 Amend appropriate diagnostic messages with the command line option that controls them.
1184 Common Joined RejectNegative Var(common_deferred_options) Defer
1185 -fdisable-[tree|rtl|ipa]-<pass>=range1+range2 disables an optimization pass.
1188 Common Joined RejectNegative Var(common_deferred_options) Defer
1189 -fenable-[tree|rtl|ipa]-<pass>=range1+range2 enables an optimization pass.
1192 Common Joined RejectNegative Var(common_deferred_options) Defer
1193 -fdump-<type> Dump various compiler internals to a file.
1196 Driver RejectNegative
1199 Common RejectNegative Joined Var(flag_dump_final_insns)
1200 -fdump-final-insns=filename Dump to filename the insns at the end of translation.
1203 Common RejectNegative Joined Var(flag_dump_go_spec)
1204 -fdump-go-spec=filename Write all declarations to file as Go code.
1207 Common Report Var(flag_dump_noaddr)
1208 Suppress output of addresses in debugging dumps.
1211 Common Driver Var(flag_report_bug)
1212 Collect and dump debug information into temporary file if ICE in C/C++
1215 fdump-internal-locations
1216 Common Var(flag_dump_locations) Init(0)
1217 Dump detailed information on GCC's internal representation of source code locations.
1220 Common Var(flag_dump_passes) Init(0)
1221 Dump optimization passes.
1224 Common Report Var(flag_dump_unnumbered)
1225 Suppress output of instruction numbers, line number notes and addresses in debugging dumps.
1227 fdump-unnumbered-links
1228 Common Report Var(flag_dump_unnumbered_links)
1229 Suppress output of previous and next insn numbers in debugging dumps.
1232 Common Report Var(flag_dwarf2_cfi_asm) Init(HAVE_GAS_CFI_DIRECTIVE)
1233 Enable CFI tables via GAS assembler directives.
1236 Common Report Var(flag_early_inlining) Init(1) Optimization
1237 Perform early inlining.
1239 feliminate-dwarf2-dups
1240 Common Report Var(flag_eliminate_dwarf2_dups)
1241 Perform DWARF duplicate elimination.
1244 Common Report Var(flag_ipa_sra) Init(0) Optimization
1245 Perform interprocedural reduction of aggregates.
1247 feliminate-unused-debug-symbols
1248 Common Report Var(flag_debug_only_used_symbols)
1249 Perform unused symbol elimination in debug info.
1251 feliminate-unused-debug-types
1252 Common Report Var(flag_eliminate_unused_debug_types) Init(1)
1253 Perform unused type elimination in debug info.
1255 femit-class-debug-always
1256 Common Report Var(flag_emit_class_debug_always) Init(0)
1257 Do not suppress C++ class debug information.
1260 Common Report Var(flag_exceptions) Optimization
1261 Enable exception handling.
1263 fexpensive-optimizations
1264 Common Report Var(flag_expensive_optimizations) Optimization
1265 Perform a number of minor, expensive optimizations.
1268 Common Joined RejectNegative Enum(excess_precision) Var(flag_excess_precision_cmdline) Init(EXCESS_PRECISION_DEFAULT)
1269 -fexcess-precision=[fast|standard] Specify handling of excess floating-point precision.
1272 Name(excess_precision) Type(enum excess_precision) UnknownError(unknown excess precision style %qs)
1275 Enum(excess_precision) String(fast) Value(EXCESS_PRECISION_FAST)
1278 Enum(excess_precision) String(standard) Value(EXCESS_PRECISION_STANDARD)
1284 Common Var(flag_fat_lto_objects)
1285 Output lto objects containing both the intermediate language and binary output.
1288 Common Report Var(flag_finite_math_only) Optimization SetByCombined
1289 Assume no NaNs or infinities are generated.
1292 Common Joined RejectNegative Var(common_deferred_options) Defer
1293 -ffixed-<register> Mark <register> as being unavailable to the compiler.
1296 Common Report Var(flag_float_store) Optimization
1297 Don't allocate floats and doubles in extended-precision registers.
1301 Does nothing. Preserved for backward compatibility.
1304 Common Report Var(flag_forward_propagate) Optimization
1305 Perform a forward propagation pass on RTL.
1308 Common Joined RejectNegative Enum(fp_contract_mode) Var(flag_fp_contract_mode) Init(FP_CONTRACT_FAST) Optimization
1309 -ffp-contract=[off|on|fast] Perform floating-point expression contraction.
1312 Name(fp_contract_mode) Type(enum fp_contract_mode) UnknownError(unknown floating point contraction style %qs)
1315 Enum(fp_contract_mode) String(off) Value(FP_CONTRACT_OFF)
1317 ; Not implemented, fall back to conservative FP_CONTRACT_OFF.
1319 Enum(fp_contract_mode) String(on) Value(FP_CONTRACT_OFF)
1322 Enum(fp_contract_mode) String(fast) Value(FP_CONTRACT_FAST)
1324 ; Nonzero means don't put addresses of constant functions in registers.
1325 ; Used for compiling the Unix kernel, where strange substitutions are
1326 ; done on the assembly output.
1328 Common Report Var(flag_no_function_cse,0) Optimization
1329 Allow function addresses to be held in registers.
1332 Common Report Var(flag_function_sections)
1333 Place each function into its own section.
1336 Common Report Var(flag_gcse) Optimization
1337 Perform global common subexpression elimination.
1340 Common Report Var(flag_gcse_lm) Init(1) Optimization
1341 Perform enhanced load motion during global common subexpression elimination.
1344 Common Report Var(flag_gcse_sm) Init(0) Optimization
1345 Perform store motion after global common subexpression elimination.
1348 Common Report Var(flag_gcse_las) Init(0) Optimization
1349 Perform redundant load after store elimination in global common subexpression
1353 Common Report Var(flag_gcse_after_reload) Optimization
1354 Perform global common subexpression elimination after register allocation has
1358 Name(dwarf_gnat_encodings) Type(int)
1361 Enum(dwarf_gnat_encodings) String(all) Value(DWARF_GNAT_ENCODINGS_ALL)
1364 Enum(dwarf_gnat_encodings) String(gdb) Value(DWARF_GNAT_ENCODINGS_GDB)
1367 Enum(dwarf_gnat_encodings) String(minimal) Value(DWARF_GNAT_ENCODINGS_MINIMAL)
1370 Common Enum(dwarf_gnat_encodings) Joined RejectNegative Report Undocumented Var(gnat_encodings)
1371 -fgnat-encodings=[all|gdb|minimal] Select the balance between GNAT encodings and standard DWARF emitted in the debug information
1373 ; This option is not documented yet as its semantics will change.
1375 Common Report Var(flag_graphite) Optimization
1376 Enable in and out of Graphite representation.
1379 Common Report Var(flag_graphite_identity) Optimization
1380 Enable Graphite Identity transformation.
1382 fhoist-adjacent-loads
1383 Common Report Var(flag_hoist_adjacent_loads) Optimization
1384 Enable hoisting adjacent loads to encourage generating conditional move
1388 Common Undocumented Report Var(flag_keep_gc_roots_live) Optimization
1389 ; Always keep a pointer to a live memory block
1391 floop-parallelize-all
1392 Common Report Var(flag_loop_parallelize_all) Optimization
1393 Mark all loops as parallel.
1396 Common Alias(floop-nest-optimize)
1397 Enable loop nest transforms. Same as -floop-nest-optimize.
1400 Common Alias(floop-nest-optimize)
1401 Enable loop nest transforms. Same as -floop-nest-optimize.
1404 Common Alias(floop-nest-optimize)
1405 Enable loop nest transforms. Same as -floop-nest-optimize.
1407 floop-unroll-and-jam
1408 Common Alias(floop-nest-optimize)
1409 Enable loop nest transforms. Same as -floop-nest-optimize.
1412 Common Report Var(flag_tm)
1413 Enable support for GNU transactional memory.
1416 Common Report Var(flag_gnu_unique) Init(1)
1417 Use STB_GNU_UNIQUE if supported by the assembler.
1421 Does nothing. Preserved for backward compatibility.
1424 Common Report Var(flag_loop_nest_optimize) Optimization
1425 Enable the loop nest optimizer.
1427 fstrict-volatile-bitfields
1428 Common Report Var(flag_strict_volatile_bitfields) Init(-1) Optimization
1429 Force bitfield accesses to match their type width.
1431 fguess-branch-probability
1432 Common Report Var(flag_guess_branch_prob) Optimization
1433 Enable guessing of branch probabilities.
1435 ; Nonzero means ignore `#ident' directives. 0 means handle them.
1436 ; Generate position-independent code for executables if possible
1437 ; On SVR4 targets, it also controls whether or not to emit a
1438 ; string identifying the compiler.
1440 Common Report Var(flag_no_ident,0)
1441 Process #ident directives.
1444 Common Report Var(flag_if_conversion) Optimization
1445 Perform conversion of conditional jumps to branchless equivalents.
1448 Common Report Var(flag_if_conversion2) Optimization
1449 Perform conversion of conditional jumps to conditional execution.
1452 Common Joined RejectNegative Enum(stack_reuse_level) Var(flag_stack_reuse) Init(SR_ALL) Optimization
1453 -fstack-reuse=[all|named_vars|none] Set stack reuse level for local variables.
1456 Name(stack_reuse_level) Type(enum stack_reuse_level) UnknownError(unknown Stack Reuse Level %qs)
1459 Enum(stack_reuse_level) String(all) Value(SR_ALL)
1462 Enum(stack_reuse_level) String(named_vars) Value(SR_NAMED_VARS)
1465 Enum(stack_reuse_level) String(none) Value(SR_NONE)
1467 ftree-loop-if-convert
1468 Common Report Var(flag_tree_loop_if_convert) Init(-1) Optimization
1469 Convert conditional jumps in innermost loops to branchless equivalents.
1471 ftree-loop-if-convert-stores
1472 Common Report Var(flag_tree_loop_if_convert_stores) Optimization
1473 Also if-convert conditional jumps containing memory writes.
1475 ; -finhibit-size-directive inhibits output of .size for ELF.
1476 ; This is used only for compiling crtstuff.c,
1477 ; and it may be extended to other effects
1478 ; needed for crtstuff.c on other systems.
1479 finhibit-size-directive
1480 Common Report Var(flag_inhibit_size_directive)
1481 Do not generate .size directives.
1484 Common Report Var(flag_indirect_inlining) Optimization
1485 Perform indirect inlining.
1487 ; General flag to enable inlining. Specifying -fno-inline will disable
1488 ; all inlining apart from always-inline functions.
1490 Common Report Var(flag_no_inline,0) Init(0) Optimization
1491 Enable inlining of function declared \"inline\", disabling disables all inlining.
1493 finline-small-functions
1494 Common Report Var(flag_inline_small_functions) Optimization
1495 Integrate functions into their callers when code size is known not to grow.
1498 Common Report Var(flag_inline_functions) Optimization
1499 Integrate functions not declared \"inline\" into their callers when profitable.
1501 finline-functions-called-once
1502 Common Report Var(flag_inline_functions_called_once) Optimization
1503 Integrate functions only required by their single caller.
1506 Common RejectNegative Joined Alias(finline-limit=)
1509 Common RejectNegative Joined UInteger
1510 -finline-limit=<number> Limit the size of inlined functions to <number>.
1513 Common Report Var(flag_inline_atomics) Init(1) Optimization
1514 Inline __atomic operations when a lock free instruction sequence is available.
1516 finstrument-functions
1517 Common Report Var(flag_instrument_function_entry_exit)
1518 Instrument function entry and exit with profiling calls.
1520 finstrument-functions-exclude-function-list=
1521 Common RejectNegative Joined
1522 -finstrument-functions-exclude-function-list=name,... Do not instrument listed functions.
1524 finstrument-functions-exclude-file-list=
1525 Common RejectNegative Joined
1526 -finstrument-functions-exclude-file-list=filename,... Do not instrument functions listed in files.
1529 Common Report Var(flag_ipa_cp) Optimization
1530 Perform interprocedural constant propagation.
1533 Common Report Var(flag_ipa_cp_clone) Optimization
1534 Perform cloning to make Interprocedural constant propagation stronger.
1537 Common Report Var(flag_ipa_cp_alignment) Optimization
1538 Perform alignment discovery and propagation to make Interprocedural constant propagation stronger.
1541 Common Report Var(flag_ipa_profile) Init(0) Optimization
1542 Perform interprocedural profile propagation.
1545 Common Report Var(flag_ipa_pta) Init(0) Optimization
1546 Perform interprocedural points-to analysis.
1549 Common Report Var(flag_ipa_pure_const) Init(0) Optimization
1550 Discover pure and const functions.
1553 Common Report Var(flag_ipa_icf) Optimization
1554 Perform Identical Code Folding for functions and read-only variables.
1557 Common Report Var(flag_ipa_icf_functions) Optimization
1558 Perform Identical Code Folding for functions.
1561 Common Report Var(flag_ipa_icf_variables)
1562 Perform Identical Code Folding for variables.
1565 Common Report Var(flag_ipa_reference) Init(0) Optimization
1566 Discover readonly and non addressable static variables.
1570 Does nothing. Preserved for backward compatibility.
1574 Does nothing. Preserved for backward compatibility.
1577 Common Joined RejectNegative Enum(ira_algorithm) Var(flag_ira_algorithm) Init(IRA_ALGORITHM_CB) Optimization
1578 -fira-algorithm=[CB|priority] Set the used IRA algorithm.
1581 Name(ira_algorithm) Type(enum ira_algorithm) UnknownError(unknown IRA algorithm %qs)
1584 Enum(ira_algorithm) String(CB) Value(IRA_ALGORITHM_CB)
1587 Enum(ira_algorithm) String(priority) Value(IRA_ALGORITHM_PRIORITY)
1590 Common Joined RejectNegative Enum(ira_region) Var(flag_ira_region) Init(IRA_REGION_AUTODETECT) Optimization
1591 -fira-region=[one|all|mixed] Set regions for IRA.
1594 Name(ira_region) Type(enum ira_region) UnknownError(unknown IRA region %qs)
1597 Enum(ira_region) String(one) Value(IRA_REGION_ONE)
1600 Enum(ira_region) String(all) Value(IRA_REGION_ALL)
1603 Enum(ira_region) String(mixed) Value(IRA_REGION_MIXED)
1606 Common Report Var(flag_ira_hoist_pressure) Init(1) Optimization
1607 Use IRA based register pressure calculation
1608 in RTL hoist optimizations.
1611 Common Report Var(flag_ira_loop_pressure) Optimization
1612 Use IRA based register pressure calculation
1613 in RTL loop optimizations.
1615 fira-share-save-slots
1616 Common Report Var(flag_ira_share_save_slots) Init(1) Optimization
1617 Share slots for saving different hard registers.
1619 fira-share-spill-slots
1620 Common Report Var(flag_ira_share_spill_slots) Init(1) Optimization
1621 Share stack slots for spilled pseudo-registers.
1624 Common RejectNegative Joined UInteger Var(flag_ira_verbose) Init(5)
1625 -fira-verbose=<number> Control IRA's level of diagnostic messages.
1628 Common Report Var(flag_ivopts) Init(1) Optimization
1629 Optimize induction variables on trees.
1632 Common Var(flag_jump_tables) Init(1) Optimization
1633 Use jump tables for sufficiently large switch statements.
1635 fkeep-inline-functions
1636 Common Report Var(flag_keep_inline_functions)
1637 Generate code for functions even if they are fully inlined.
1639 fkeep-static-functions
1640 Common Report Var(flag_keep_static_functions)
1641 Generate code for static functions even if they are never called.
1644 Common Report Var(flag_keep_static_consts) Init(1)
1645 Emit static const variables even if they are not used.
1648 Common Report Var(flag_leading_underscore) Init(-1)
1649 Give external symbols a leading underscore.
1653 Does nothing. Preserved for backward compatibility.
1656 Common Report Var(flag_lra_remat) Optimization
1657 Do CFG-sensitive rematerialization in LRA.
1661 Enable link-time optimization.
1664 Common RejectNegative Joined Var(flag_lto)
1665 Link-time optimization with number of parallel jobs or jobserver.
1668 Name(lto_partition_model) Type(enum lto_partition_model) UnknownError(unknown LTO partitioning model %qs)
1671 Enum(lto_partition_model) String(none) Value(LTO_PARTITION_NONE)
1674 Enum(lto_partition_model) String(one) Value(LTO_PARTITION_ONE)
1677 Enum(lto_partition_model) String(balanced) Value(LTO_PARTITION_BALANCED)
1680 Enum(lto_partition_model) String(1to1) Value(LTO_PARTITION_1TO1)
1683 Enum(lto_partition_model) String(max) Value(LTO_PARTITION_MAX)
1686 Common Joined RejectNegative Enum(lto_partition_model) Var(flag_lto_partition) Init(LTO_PARTITION_BALANCED)
1687 Specify the algorithm to partition symbols and vars at linktime.
1689 ; The initial value of -1 comes from Z_DEFAULT_COMPRESSION in zlib.h.
1690 flto-compression-level=
1691 Common Joined RejectNegative UInteger Var(flag_lto_compression_level) Init(-1)
1692 -flto-compression-level=<number> Use zlib compression level <number> for IL.
1694 flto-odr-type-merging
1695 Common Report Var(flag_lto_odr_type_mering) Init(1)
1696 Merge C++ types using One Definition Rule.
1699 Common Report Var(flag_lto_report) Init(0)
1700 Report various link-time optimization statistics.
1703 Common Report Var(flag_lto_report_wpa) Init(0)
1704 Report various link-time optimization statistics for WPA only.
1707 Common Report Var(flag_errno_math) Init(1) Optimization SetByCombined
1708 Set errno after built-in math functions.
1711 Common Joined RejectNegative UInteger Var(flag_max_errors)
1712 -fmax-errors=<number> Maximum number of errors to report.
1715 Common Report Var(mem_report)
1716 Report on permanent memory allocation.
1719 Common Report Var(mem_report_wpa)
1720 Report on permanent memory allocation in WPA only.
1722 ; This will attempt to merge constant section constants, if 1 only
1723 ; string constants and constants from constant pool, if 2 also constant
1725 fmerge-all-constants
1726 Common Report Var(flag_merge_constants,2) Init(1)
1727 Attempt to merge identical constants and constant variables.
1730 Common Report Var(flag_merge_constants,1)
1731 Attempt to merge identical constants across compilation units.
1733 fmerge-debug-strings
1734 Common Report Var(flag_merge_debug_strings) Init(1)
1735 Attempt to merge identical debug strings across compilation units.
1738 Common RejectNegative Joined UInteger
1739 -fmessage-length=<number> Limit diagnostics to <number> characters per line. 0 suppresses line-wrapping.
1742 Common Report Var(flag_modulo_sched) Optimization
1743 Perform SMS based modulo scheduling before the first scheduling pass.
1745 fmodulo-sched-allow-regmoves
1746 Common Report Var(flag_modulo_sched_allow_regmoves) Optimization
1747 Perform SMS based modulo scheduling with register moves allowed.
1749 fmove-loop-invariants
1750 Common Report Var(flag_move_loop_invariants) Optimization
1751 Move loop invariant computations out of loops.
1754 Common Var(flag_dce) Init(1) Optimization
1755 Use the RTL dead code elimination pass.
1758 Common Var(flag_dse) Init(1) Optimization
1759 Use the RTL dead store elimination pass.
1761 freschedule-modulo-scheduled-loops
1762 Common Report Var(flag_resched_modulo_sched) Optimization
1763 Enable/Disable the traditional scheduling in loops that already passed modulo scheduling.
1765 fnon-call-exceptions
1766 Common Report Var(flag_non_call_exceptions) Optimization
1767 Support synchronous non-call exceptions.
1770 Common Driver Joined MissingArgError(options or targets missing after %qs)
1771 -foffload=<targets>=<options> Specify offloading targets and options for them.
1774 Common Joined RejectNegative Enum(offload_abi) Var(flag_offload_abi) Init(OFFLOAD_ABI_UNSET)
1775 -foffload-abi=[lp64|ilp32] Set the ABI to use in an offload compiler.
1778 Name(offload_abi) Type(enum offload_abi) UnknownError(unknown offload ABI %qs)
1781 Enum(offload_abi) String(ilp32) Value(OFFLOAD_ABI_ILP32)
1784 Enum(offload_abi) String(lp64) Value(OFFLOAD_ABI_LP64)
1787 Common Report Var(flag_omit_frame_pointer) Optimization
1788 When possible do not generate stack frames.
1791 Common Report Var(flag_opt_info) Optimization
1792 Enable all optimization info dumps on stderr.
1795 Common Joined RejectNegative Var(common_deferred_options) Defer
1796 -fopt-info[-<type>=filename] Dump compiler optimization details.
1798 foptimize-register-move
1800 Does nothing. Preserved for backward compatibility.
1802 foptimize-sibling-calls
1803 Common Report Var(flag_optimize_sibling_calls) Optimization
1804 Optimize sibling and tail recursive calls.
1807 Common Report Var(flag_partial_inlining) Optimization
1808 Perform partial inlining.
1811 Common Report Var(pre_ipa_mem_report)
1812 Report on memory allocation before interprocedural optimization.
1814 fpost-ipa-mem-report
1815 Common Report Var(post_ipa_mem_report)
1816 Report on memory allocation before interprocedural optimization.
1819 Common Report Var(flag_pack_struct) Optimization
1820 Pack structure members together without holes.
1823 Common RejectNegative Joined UInteger Optimization
1824 -fpack-struct=<number> Set initial maximum structure member alignment.
1827 Common Report Var(flag_pcc_struct_return,1) Init(DEFAULT_PCC_STRUCT_RETURN)
1828 Return small aggregates in memory, not registers.
1831 Common Report Var(flag_peel_loops) Optimization
1832 Perform loop peeling.
1835 Common Report Var(flag_no_peephole,0) Optimization
1836 Enable machine specific peephole optimizations.
1839 Common Report Var(flag_peephole2) Optimization
1840 Enable an RTL peephole pass before sched2.
1843 Common Report Var(flag_pic,2) Negative(fPIE)
1844 Generate position-independent code if possible (large mode).
1847 Common Report Var(flag_pie,2) Negative(fpic) Init(-1)
1848 Generate position-independent code for executables if possible (large mode).
1851 Common Report Var(flag_pic,1) Negative(fpie)
1852 Generate position-independent code if possible (small mode).
1855 Common Report Var(flag_pie,1) Negative(fPIC) Init(-1)
1856 Generate position-independent code for executables if possible (small mode).
1859 Common Report Var(flag_plt) Init(1) Optimization
1860 Use PLT for PIC calls (-fno-plt: load the address from GOT at call site).
1863 Common Joined RejectNegative Var(common_deferred_options) Defer
1864 Specify a plugin to load.
1867 Common Joined RejectNegative Var(common_deferred_options) Defer
1868 -fplugin-arg-<name>-<key>[=<value>] Specify argument <key>=<value> for plugin <name>.
1870 fpredictive-commoning
1871 Common Report Var(flag_predictive_commoning) Optimization
1872 Run predictive commoning optimization.
1874 fprefetch-loop-arrays
1875 Common Report Var(flag_prefetch_loop_arrays) Init(-1) Optimization
1876 Generate prefetch instructions, if available, for arrays in loops.
1879 Common Report Var(profile_flag)
1880 Enable basic program profiling code.
1883 Common Report Var(profile_arc_flag)
1884 Insert arc-based program profiling code.
1887 Common Joined RejectNegative Var(profile_data_prefix)
1888 Set the top-level directory for storing the profile data.
1889 The default is 'pwd'.
1892 Common Report Var(flag_profile_correction)
1893 Enable correction of flow inconsistent profile data input.
1897 Enable common options for generating profile info for profile feedback directed optimizations.
1900 Common Joined RejectNegative
1901 Enable common options for generating profile info for profile feedback directed optimizations, and set -fprofile-dir=.
1904 Common Var(flag_profile_use)
1905 Enable common options for performing profile feedback directed optimizations.
1908 Common Joined RejectNegative
1909 Enable common options for performing profile feedback directed optimizations, and set -fprofile-dir=.
1912 Common Report Var(flag_profile_values)
1913 Insert code to profile values of expressions.
1916 Common Report Var(profile_report)
1917 Report on consistency of profile.
1919 fprofile-reorder-functions
1920 Common Report Var(flag_profile_reorder_functions)
1921 Enable function reordering that improves code placement.
1924 Common Var(common_deferred_options) Defer
1927 Common Joined RejectNegative Var(common_deferred_options) Defer
1928 -frandom-seed=<string> Make compile reproducible using <string>.
1930 ; This switch causes the command line that was used to create an
1931 ; object file to be recorded into the object file. The exact format
1932 ; of this recording is target and binary file format dependent.
1933 ; It is related to the -fverbose-asm switch, but that switch only
1934 ; records information in the assembler output file as comments, so
1935 ; they never reach the object file.
1936 frecord-gcc-switches
1937 Common Report Var(flag_record_gcc_switches)
1938 Record gcc command line switches in the object file.
1941 Common Report Var(flag_pcc_struct_return,0) Optimization
1942 Return small aggregates in registers.
1946 Does nothing. Preserved for backward compatibility.
1949 Common Report Var(flag_lifetime_dse) Init(1) Optimization
1950 Tell DSE that the storage for a C++ object is dead when the constructor
1951 starts and when the destructor finishes.
1953 flive-range-shrinkage
1954 Common Report Var(flag_live_range_shrinkage) Init(0) Optimization
1955 Relief of register pressure through live range shrinkage.
1958 Common Report Var(flag_rename_registers) Init(2) Optimization
1959 Perform a register renaming optimization pass.
1962 Common Report Var(flag_schedule_fusion) Init(2) Optimization
1963 Perform a target dependent instruction fusion optimization pass.
1966 Common Report Var(flag_reorder_blocks) Optimization
1967 Reorder basic blocks to improve code placement.
1969 freorder-blocks-algorithm=
1970 Common Joined RejectNegative Enum(reorder_blocks_algorithm) Var(flag_reorder_blocks_algorithm) Init(REORDER_BLOCKS_ALGORITHM_SIMPLE) Optimization
1971 -freorder-blocks-algorithm=[simple|stc] Set the used basic block reordering algorithm.
1974 Name(reorder_blocks_algorithm) Type(enum reorder_blocks_algorithm) UnknownError(unknown basic block reordering algorithm %qs)
1977 Enum(reorder_blocks_algorithm) String(simple) Value(REORDER_BLOCKS_ALGORITHM_SIMPLE)
1980 Enum(reorder_blocks_algorithm) String(stc) Value(REORDER_BLOCKS_ALGORITHM_STC)
1982 freorder-blocks-and-partition
1983 Common Report Var(flag_reorder_blocks_and_partition) Optimization
1984 Reorder basic blocks and partition into hot and cold sections.
1987 Common Report Var(flag_reorder_functions) Optimization
1988 Reorder functions to improve code placement.
1990 frerun-cse-after-loop
1991 Common Report Var(flag_rerun_cse_after_loop) Optimization
1992 Add a common subexpression elimination pass after loop optimizations.
1996 Does nothing. Preserved for backward compatibility.
1999 Common Report Var(flag_rounding_math) Optimization SetByCombined
2000 Disable optimizations that assume default FP rounding behavior.
2003 Common Report Var(flag_schedule_interblock) Init(1) Optimization
2004 Enable scheduling across basic blocks.
2007 Common Report Var(flag_sched_pressure) Init(0) Optimization
2008 Enable register pressure sensitive insn scheduling.
2011 Common Report Var(flag_schedule_speculative) Init(1) Optimization
2012 Allow speculative motion of non-loads.
2015 Common Report Var(flag_schedule_speculative_load) Optimization
2016 Allow speculative motion of some loads.
2018 fsched-spec-load-dangerous
2019 Common Report Var(flag_schedule_speculative_load_dangerous) Optimization
2020 Allow speculative motion of more loads.
2023 Common RejectNegative Joined UInteger Var(sched_verbose_param) Init(1)
2024 -fsched-verbose=<number> Set the verbosity level of the scheduler.
2026 fsched2-use-superblocks
2027 Common Report Var(flag_sched2_use_superblocks) Optimization
2028 If scheduling post reload, do superblock scheduling.
2032 Does nothing. Preserved for backward compatibility.
2035 Common Report Var(flag_schedule_insns) Optimization
2036 Reschedule instructions before register allocation.
2039 Common Report Var(flag_schedule_insns_after_reload) Optimization
2040 Reschedule instructions after register allocation.
2042 ; This flag should be on when a target implements non-trivial
2043 ; scheduling hooks, maybe saving some information for its own sake.
2044 ; On IA64, for example, this is used for correct bundling.
2045 fselective-scheduling
2046 Common Report Var(flag_selective_scheduling) Optimization
2047 Schedule instructions using selective scheduling algorithm.
2049 fselective-scheduling2
2050 Common Report Var(flag_selective_scheduling2) Optimization
2051 Run selective scheduling after reload.
2053 fsel-sched-pipelining
2054 Common Report Var(flag_sel_sched_pipelining) Init(0) Optimization
2055 Perform software pipelining of inner loops during selective scheduling.
2057 fsel-sched-pipelining-outer-loops
2058 Common Report Var(flag_sel_sched_pipelining_outer_loops) Init(0) Optimization
2059 Perform software pipelining of outer loops during selective scheduling.
2061 fsel-sched-reschedule-pipelined
2062 Common Report Var(flag_sel_sched_reschedule_pipelined) Init(0) Optimization
2063 Reschedule pipelined regions without pipelining.
2065 fsemantic-interposition
2066 Common Report Var(flag_semantic_interposition) Init(1)
2067 Allow interposing function (or variables) by ones with different semantics (or initializer) respectively by dynamic linker.
2069 ; sched_stalled_insns means that insns can be moved prematurely from the queue
2070 ; of stalled insns into the ready list.
2071 fsched-stalled-insns
2072 Common Report Var(flag_sched_stalled_insns) Optimization UInteger
2073 Allow premature scheduling of queued insns.
2075 fsched-stalled-insns=
2076 Common RejectNegative Joined UInteger Optimization
2077 -fsched-stalled-insns=<number> Set number of queued insns that can be prematurely scheduled.
2079 ; sched_stalled_insns_dep controls how many recently scheduled cycles will
2080 ; be examined for a dependency on a stalled insn that is candidate for
2081 ; premature removal from the queue of stalled insns into the ready list (has
2082 ; an effect only if the flag 'sched_stalled_insns' is set).
2083 fsched-stalled-insns-dep
2084 Common Report Var(flag_sched_stalled_insns_dep,1) Init(1) Optimization UInteger
2085 Set dependence distance checking in premature scheduling of queued insns.
2087 fsched-stalled-insns-dep=
2088 Common RejectNegative Joined UInteger Optimization
2089 -fsched-stalled-insns-dep=<number> Set dependence distance checking in premature scheduling of queued insns.
2091 fsched-group-heuristic
2092 Common Report Var(flag_sched_group_heuristic) Init(1) Optimization
2093 Enable the group heuristic in the scheduler.
2095 fsched-critical-path-heuristic
2096 Common Report Var(flag_sched_critical_path_heuristic) Init(1) Optimization
2097 Enable the critical path heuristic in the scheduler.
2099 fsched-spec-insn-heuristic
2100 Common Report Var(flag_sched_spec_insn_heuristic) Init(1) Optimization
2101 Enable the speculative instruction heuristic in the scheduler.
2103 fsched-rank-heuristic
2104 Common Report Var(flag_sched_rank_heuristic) Init(1) Optimization
2105 Enable the rank heuristic in the scheduler.
2107 fsched-last-insn-heuristic
2108 Common Report Var(flag_sched_last_insn_heuristic) Init(1) Optimization
2109 Enable the last instruction heuristic in the scheduler.
2111 fsched-dep-count-heuristic
2112 Common Report Var(flag_sched_dep_count_heuristic) Init(1) Optimization
2113 Enable the dependent count heuristic in the scheduler.
2116 Common Report Var(flag_section_anchors) Optimization
2117 Access data in the same section from shared anchor points.
2121 Does nothing. Preserved for backward compatibility.
2125 Does nothing. Preserved for backward compatibility.
2128 Common Report Var(flag_ree) Init(0)
2129 Turn on Redundant Extensions Elimination pass.
2132 Common Report Var(flag_show_column) Init(1)
2133 Show column numbers in diagnostics, when available. Default on.
2136 Common Report Var(flag_shrink_wrap) Optimization
2137 Emit function prologues only before parts of the function that need it,
2138 rather than at the top of the function.
2141 Common Report Var(flag_signaling_nans) Optimization SetByCombined
2142 Disable optimizations observable by IEEE signaling NaNs.
2145 Common Report Var(flag_signed_zeros) Init(1) Optimization SetByCombined
2146 Disable floating point optimizations that ignore the IEEE signedness of zero.
2148 fsingle-precision-constant
2149 Common Report Var(flag_single_precision_constant) Optimization
2150 Convert floating point constants to single precision constants.
2152 fsplit-ivs-in-unroller
2153 Common Report Var(flag_split_ivs_in_unroller) Init(1) Optimization
2154 Split lifetimes of induction variables when loops are unrolled.
2157 Common Report Var(flag_split_stack) Init(-1)
2158 Generate discontiguous stack frames.
2161 Common Report Var(flag_split_wide_types) Optimization
2162 Split wide types into independent registers.
2165 Common Report Var(flag_ssa_backprop) Init(1) Optimization
2166 Enable backward propagation of use properties at the SSA level.
2169 Common Report Var(flag_ssa_phiopt) Optimization
2170 Optimize conditional patterns using SSA PHI nodes.
2173 Common Report Var(flag_stdarg_opt) Init(1) Optimization
2174 Optimize amount of stdarg registers saved to stack at start of function.
2176 fvariable-expansion-in-unroller
2177 Common Report Var(flag_variable_expansion_in_unroller) Optimization
2178 Apply variable expansion when loops are unrolled.
2181 Common Report RejectNegative Joined
2182 -fstack-check=[no|generic|specific] Insert stack checking code into the program.
2185 Common Alias(fstack-check=, specific, no)
2186 Insert stack checking code into the program. Same as -fstack-check=specific.
2189 Common Var(common_deferred_options) Defer
2191 fstack-limit-register=
2192 Common RejectNegative Joined Var(common_deferred_options) Defer
2193 -fstack-limit-register=<register> Trap if the stack goes past <register>.
2195 fstack-limit-symbol=
2196 Common RejectNegative Joined Var(common_deferred_options) Defer
2197 -fstack-limit-symbol=<name> Trap if the stack goes past symbol <name>.
2200 Common Report Var(flag_stack_protect, 1) Init(-1)
2201 Use propolice as a stack protection method.
2203 fstack-protector-all
2204 Common Report RejectNegative Var(flag_stack_protect, 2) Init(-1)
2205 Use a stack protection method for every function.
2207 fstack-protector-strong
2208 Common Report RejectNegative Var(flag_stack_protect, 3) Init(-1)
2209 Use a smart stack protection method for certain functions.
2211 fstack-protector-explicit
2212 Common Report RejectNegative Var(flag_stack_protect, 4)
2213 Use stack protection method only for functions with the stack_protect attribute.
2216 Common RejectNegative Var(flag_stack_usage)
2217 Output stack usage information on a per-function basis.
2221 Does nothing. Preserved for backward compatibility.
2223 ; Nonzero if we should do (language-dependent) alias analysis.
2224 ; Typically, this analysis will assume that expressions of certain
2225 ; types do not alias expressions of certain other types. Only used
2226 ; if alias analysis (in general) is enabled.
2228 Common Report Var(flag_strict_aliasing) Optimization
2229 Assume strict aliasing rules apply.
2232 Common Report Var(flag_strict_overflow) Optimization
2233 Treat signed overflow as undefined.
2236 Common Report Var(flag_sync_libcalls) Init(1)
2237 Implement __atomic operations via libcalls to legacy __sync functions.
2240 Common Report Var(flag_syntax_only)
2241 Check for syntax errors, then stop.
2244 Common Report Var(flag_test_coverage)
2245 Create data files needed by \"gcov\".
2248 Common Report Var(flag_thread_jumps) Optimization
2249 Perform jump threading optimizations.
2252 Common Report Var(time_report)
2253 Report the time taken by each compiler pass.
2256 Common Joined RejectNegative Enum(tls_model) Var(flag_tls_default) Init(TLS_MODEL_GLOBAL_DYNAMIC)
2257 -ftls-model=[global-dynamic|local-dynamic|initial-exec|local-exec] Set the default thread-local storage code generation model.
2260 Name(tls_model) Type(enum tls_model) UnknownError(unknown TLS model %qs)
2263 Enum(tls_model) String(global-dynamic) Value(TLS_MODEL_GLOBAL_DYNAMIC)
2266 Enum(tls_model) String(local-dynamic) Value(TLS_MODEL_LOCAL_DYNAMIC)
2269 Enum(tls_model) String(initial-exec) Value(TLS_MODEL_INITIAL_EXEC)
2272 Enum(tls_model) String(local-exec) Value(TLS_MODEL_LOCAL_EXEC)
2275 Common Report Var(flag_toplevel_reorder) Init(2)
2276 Reorder top level functions, variables, and asms.
2279 Common Report Var(flag_tracer) Optimization
2280 Perform superblock formation via tail duplication.
2282 ; Zero means that floating-point math operations cannot generate a
2283 ; (user-visible) trap. This is the case, for example, in nonstop
2284 ; IEEE 754 arithmetic.
2286 Common Report Var(flag_trapping_math) Init(1) Optimization SetByCombined
2287 Assume floating-point operations can trap.
2290 Common Report Var(flag_trapv) Optimization
2291 Trap for signed overflow in addition, subtraction and multiplication.
2294 Common Report Var(flag_tree_ccp) Optimization
2295 Enable SSA-CCP optimization on trees.
2298 Common Report Var(flag_tree_bit_ccp) Optimization
2299 Enable SSA-BIT-CCP optimization on trees.
2303 Does nothing. Preserved for backward compatibility.
2306 Common Report Var(flag_tree_ch) Optimization
2307 Enable loop header copying on trees.
2309 ftree-coalesce-inlined-vars
2310 Common Ignore RejectNegative
2311 Does nothing. Preserved for backward compatibility.
2314 Common Report Var(flag_tree_coalesce_vars) Optimization
2315 Enable SSA coalescing of user variables.
2319 Does nothing. Preserved for backward compatibility.
2322 Common Report Var(flag_tree_copy_prop) Optimization
2323 Enable copy propagation on trees.
2325 ftree-store-copy-prop
2327 Does nothing. Preserved for backward compatibility.
2330 Common Report Var(flag_tree_cselim) Init(2) Optimization
2331 Transform condition stores into unconditional ones.
2333 ftree-switch-conversion
2334 Common Report Var(flag_tree_switch_conversion) Optimization
2335 Perform conversions of switch initializations.
2338 Common Report Var(flag_tree_dce) Optimization
2339 Enable SSA dead code elimination optimization on trees.
2341 ftree-dominator-opts
2342 Common Report Var(flag_tree_dom) Optimization
2343 Enable dominator optimizations.
2346 Common Report Var(flag_tree_tail_merge) Optimization
2347 Enable tail merging on trees.
2350 Common Report Var(flag_tree_dse) Optimization
2351 Enable dead store elimination.
2354 Common Report Var(flag_tree_forwprop) Init(1) Optimization
2355 Enable forward propagation on trees.
2358 Common Report Var(flag_tree_fre) Optimization
2359 Enable Full Redundancy Elimination (FRE) on trees.
2362 Common Report Var(flag_optimize_strlen) Optimization
2363 Enable string length optimizations on trees.
2365 fisolate-erroneous-paths-dereference
2366 Common Report Var(flag_isolate_erroneous_paths_dereference) Optimization
2367 Detect paths that trigger erroneous or undefined behavior due to
2368 dereferencing a null pointer. Isolate those paths from the main control
2369 flow and turn the statement with erroneous or undefined behavior into a trap.
2371 fisolate-erroneous-paths-attribute
2372 Common Report Var(flag_isolate_erroneous_paths_attribute) Optimization
2373 Detect paths that trigger erroneous or undefined behavior due a null value
2374 being used in a way forbidden by a returns_nonnull or nonnull
2375 attribute. Isolate those paths from the main control flow and turn the
2376 statement with erroneous or undefined behavior into a trap.
2378 ftree-loop-distribution
2379 Common Report Var(flag_tree_loop_distribution) Optimization
2380 Enable loop distribution on trees.
2382 ftree-loop-distribute-patterns
2383 Common Report Var(flag_tree_loop_distribute_patterns) Optimization
2384 Enable loop distribution for patterns transformed into a library call.
2387 Common Report Var(flag_tree_loop_im) Init(1) Optimization
2388 Enable loop invariant motion on trees.
2391 Common Alias(floop-nest-optimize)
2392 Enable loop nest transforms. Same as -floop-nest-optimize.
2395 Common Report Var(flag_tree_loop_ivcanon) Init(1) Optimization
2396 Create canonical induction variables in loops.
2399 Common Report Var(flag_tree_loop_optimize) Init(1) Optimization
2400 Enable loop optimizations on tree level.
2402 ftree-parallelize-loops=
2403 Common Report Joined RejectNegative UInteger Var(flag_tree_parallelize_loops) Init(1) Optimization
2404 Enable automatic parallelization of loops.
2407 Common Report Var(flag_tree_phiprop) Init(1) Optimization
2408 Enable hoisting loads from conditional pointers.
2411 Common Report Var(flag_tree_pre) Optimization
2412 Enable SSA-PRE optimization on trees.
2415 Common Report Var(flag_tree_partial_pre) Optimization
2416 In SSA-PRE optimization on trees, enable partial-partial redundancy elimination.
2419 Common Report Var(flag_tree_pta) Optimization
2420 Perform function-local points-to analysis on trees.
2423 Common Report Var(flag_tree_reassoc) Init(1) Optimization
2424 Enable reassociation on tree level.
2428 Does nothing. Preserved for backward compatibility.
2431 Common Report Var(flag_tree_sink) Optimization
2432 Enable SSA code sinking on trees.
2435 Common Report Var(flag_tree_slsr) Optimization
2436 Perform straight-line strength reduction.
2439 Common Report Var(flag_tree_sra) Optimization
2440 Perform scalar replacement of aggregates.
2443 Common Report Var(flag_tree_ter) Optimization
2444 Replace temporary expressions in the SSA->normal pass.
2447 Common Report Var(flag_tree_live_range_split) Optimization
2448 Perform live range splitting during the SSA->normal pass.
2451 Common Report Var(flag_tree_vrp) Init(0) Optimization
2452 Perform Value Range Propagation on trees.
2455 Common Report Var(flag_split_paths) Init(0) Optimization
2456 Split paths leading to loop backedges.
2459 Common Report Var(flag_unit_at_a_time) Init(1)
2460 Compile whole compilation unit at a time.
2463 Common Report Var(flag_unroll_loops) Optimization
2464 Perform loop unrolling when iteration count is known.
2467 Common Report Var(flag_unroll_all_loops) Optimization
2468 Perform loop unrolling for all loops.
2470 ; Nonzero means that loop optimizer may assume that the induction variables
2471 ; that control loops do not overflow and that the loops with nontrivial
2472 ; exit condition are not infinite
2473 funsafe-loop-optimizations
2474 Common Report Var(flag_unsafe_loop_optimizations) Optimization
2475 Allow loop optimizations to assume that the loops behave in normal way.
2478 Common Report Var(flag_associative_math) SetByCombined Optimization
2479 Allow optimization for floating-point arithmetic which may change the
2480 result of the operation due to rounding.
2483 Common Report Var(flag_reciprocal_math) SetByCombined Optimization
2484 Same as -fassociative-math for expressions which include division.
2486 ; Nonzero means that unsafe floating-point math optimizations are allowed
2487 ; for the sake of speed. IEEE compliance is not guaranteed, and operations
2488 ; are allowed to assume that their arguments and results are "normal"
2489 ; (e.g., nonnegative for SQRT).
2490 funsafe-math-optimizations
2491 Common Report Var(flag_unsafe_math_optimizations) Optimization SetByCombined
2492 Allow math optimizations that may violate IEEE or ISO standards.
2495 Common Report Var(flag_unswitch_loops) Optimization
2496 Perform loop unswitching.
2499 Common Report Var(flag_unwind_tables) Optimization
2500 Just generate unwind tables for exception handling.
2503 Common Driver Negative(fuse-ld=gold)
2504 Use the bfd linker instead of the default linker.
2507 Common Driver Negative(fuse-ld=bfd)
2508 Use the gold linker instead of the default linker.
2511 Common Undocumented Var(flag_use_linker_plugin)
2513 ; Positive if we should track variables, negative if we should run
2514 ; the var-tracking pass only to discard debug annotations, zero if
2515 ; we're not to run it. When flag_var_tracking == 2 (AUTODETECT_VALUE) it
2516 ; will be set according to optimize, debug_info_level and debug_hooks
2517 ; in process_options ().
2519 Common Report Var(flag_var_tracking) Init(2) Optimization
2520 Perform variable tracking.
2522 ; Positive if we should track variables at assignments, negative if
2523 ; we should run the var-tracking pass only to discard debug
2524 ; annotations. When flag_var_tracking_assignments ==
2525 ; AUTODETECT_VALUE it will be set according to flag_var_tracking.
2526 fvar-tracking-assignments
2527 Common Report Var(flag_var_tracking_assignments) Init(2) Optimization
2528 Perform variable tracking by annotating assignments.
2530 ; Nonzero if we should toggle flag_var_tracking_assignments after
2531 ; processing options and computing its default. */
2532 fvar-tracking-assignments-toggle
2533 Common Report Var(flag_var_tracking_assignments_toggle) Optimization
2534 Toggle -fvar-tracking-assignments.
2536 ; Positive if we should track uninitialized variables, negative if
2537 ; we should run the var-tracking pass only to discard debug
2538 ; annotations. When flag_var_tracking_uninit == AUTODETECT_VALUE it
2539 ; will be set according to flag_var_tracking.
2540 fvar-tracking-uninit
2541 Common Report Var(flag_var_tracking_uninit) Optimization
2542 Perform variable tracking and also tag variables that are uninitialized.
2545 Common Report Var(flag_tree_vectorize) Optimization
2546 Enable vectorization on trees.
2548 ftree-vectorizer-verbose=
2549 Common Joined RejectNegative Ignore
2550 Does nothing. Preserved for backward compatibility.
2552 ftree-loop-vectorize
2553 Common Report Var(flag_tree_loop_vectorize) Optimization
2554 Enable loop vectorization on trees.
2557 Common Report Var(flag_tree_slp_vectorize) Optimization
2558 Enable basic block vectorization (SLP) on trees.
2561 Common Joined RejectNegative Enum(vect_cost_model) Var(flag_vect_cost_model) Init(VECT_COST_MODEL_DEFAULT) Optimization
2562 Specifies the cost model for vectorization.
2565 Common Joined RejectNegative Enum(vect_cost_model) Var(flag_simd_cost_model) Init(VECT_COST_MODEL_UNLIMITED) Optimization
2566 Specifies the vectorization cost model for code marked with a simd directive.
2569 Name(vect_cost_model) Type(enum vect_cost_model) UnknownError(unknown vectorizer cost model %qs)
2572 Enum(vect_cost_model) String(unlimited) Value(VECT_COST_MODEL_UNLIMITED)
2575 Enum(vect_cost_model) String(dynamic) Value(VECT_COST_MODEL_DYNAMIC)
2578 Enum(vect_cost_model) String(cheap) Value(VECT_COST_MODEL_CHEAP)
2581 Common RejectNegative Alias(fvect-cost-model=,dynamic)
2582 Enables the dynamic vectorizer cost model. Preserved for backward compatibility.
2585 Common RejectNegative Alias(fvect-cost-model=,unlimited)
2586 Enables the unlimited vectorizer cost model. Preserved for backward compatibility.
2588 ftree-vect-loop-version
2590 Does nothing. Preserved for backward compatibility.
2593 Common Report Var(flag_tree_scev_cprop) Init(1) Optimization
2594 Enable copy propagation of scalar-evolution information.
2596 ; -fverbose-asm causes extra commentary information to be produced in
2597 ; the generated assembly code (to make it more readable). This option
2598 ; is generally only of use to those who actually need to read the
2599 ; generated assembly code (perhaps while debugging the compiler itself).
2600 ; -fno-verbose-asm, the default, causes the extra information
2601 ; to not be added and is useful when comparing two assembler files.
2603 Common Report Var(flag_verbose_asm)
2604 Add extra commentary to assembler output.
2607 Common Joined RejectNegative Enum(symbol_visibility) Var(default_visibility) Init(VISIBILITY_DEFAULT)
2608 -fvisibility=[default|internal|hidden|protected] Set the default symbol visibility.
2611 Name(symbol_visibility) Type(enum symbol_visibility) UnknownError(unrecognized visibility value %qs)
2614 Enum(symbol_visibility) String(default) Value(VISIBILITY_DEFAULT)
2617 Enum(symbol_visibility) String(internal) Value(VISIBILITY_INTERNAL)
2620 Enum(symbol_visibility) String(hidden) Value(VISIBILITY_HIDDEN)
2623 Enum(symbol_visibility) String(protected) Value(VISIBILITY_PROTECTED)
2626 Common Joined RejectNegative Enum(vtv_priority) Var(flag_vtable_verify) Init(VTV_NO_PRIORITY)
2627 Validate vtable pointers before using them.
2630 Name(vtv_priority) Type(enum vtv_priority) UnknownError(unknown vtable verify initialization priority %qs)
2633 Enum(vtv_priority) String(none) Value(VTV_NO_PRIORITY)
2636 Enum(vtv_priority) String(std) Value(VTV_STANDARD_PRIORITY)
2639 Enum(vtv_priority) String(preinit) Value(VTV_PREINIT_PRIORITY)
2642 Common Var(flag_vtv_counts)
2643 Output vtable verification counters.
2646 Common Var(flag_vtv_debug)
2647 Output vtable verification pointer sets information.
2650 Common Report Var(flag_value_profile_transformations) Optimization
2651 Use expression value profiles in optimizations.
2654 Common Report Var(flag_web) Init(2) Optimization
2655 Construct webs and split unrelated uses of single variable.
2657 ftree-builtin-call-dce
2658 Common Report Var(flag_tree_builtin_call_dce) Init(0) Optimization
2659 Enable conditional dead code elimination for builtin calls.
2662 Common Report Var(flag_whole_program) Init(0)
2663 Perform whole program optimizations.
2666 Common Report Var(flag_wrapv) Optimization
2667 Assume signed arithmetic overflow wraps around.
2669 fzero-initialized-in-bss
2670 Common Report Var(flag_zero_initialized_in_bss) Init(1)
2671 Put zero initialized data in the bss section.
2674 Common JoinedOrMissing
2675 Generate debug information in default format.
2678 Common JoinedOrMissing Negative(gdwarf)
2679 Generate debug information in COFF format.
2682 Common JoinedOrMissing Negative(gdwarf-)
2683 Generate debug information in default version of DWARF format.
2686 Common Joined UInteger Var(dwarf_version) Init(4) Negative(gstabs)
2687 Generate debug information in DWARF v2 (or later) format.
2690 Common JoinedOrMissing
2691 Generate debug information in default extended format.
2694 Common Negative(gpubnames) Var(debug_generate_pub_sections, 0) Init(-1)
2695 Don't generate DWARF pubnames and pubtypes sections.
2698 Common Negative(ggnu-pubnames) Var(debug_generate_pub_sections, 1)
2699 Generate DWARF pubnames and pubtypes sections.
2702 Common Negative(gno-pubnames) Var(debug_generate_pub_sections, 2)
2703 Generate DWARF pubnames and pubtypes sections with GNU extensions.
2705 gno-record-gcc-switches
2706 Common RejectNegative Var(dwarf_record_gcc_switches,0) Init(1)
2707 Don't record gcc command line switches in DWARF DW_AT_producer.
2709 grecord-gcc-switches
2710 Common RejectNegative Var(dwarf_record_gcc_switches,1)
2711 Record gcc command line switches in DWARF DW_AT_producer.
2714 Common Driver RejectNegative Var(dwarf_split_debug_info,0) Init(0)
2715 Don't generate debug information in separate .dwo files.
2718 Common Driver RejectNegative Var(dwarf_split_debug_info,1)
2719 Generate debug information in separate .dwo files.
2722 Common JoinedOrMissing Negative(gstabs+)
2723 Generate debug information in STABS format.
2726 Common JoinedOrMissing Negative(gvms)
2727 Generate debug information in extended STABS format.
2730 Common RejectNegative Var(dwarf_strict,0) Init(0)
2731 Emit DWARF additions beyond selected version.
2734 Common Report RejectNegative Var(dwarf_strict,1)
2735 Don't emit DWARF additions beyond selected version.
2738 Common Report Var(flag_gtoggle)
2739 Toggle debug information generation.
2742 Common JoinedOrMissing Negative(gxcoff)
2743 Generate debug information in VMS format.
2746 Common JoinedOrMissing Negative(gxcoff+)
2747 Generate debug information in XCOFF format.
2750 Common JoinedOrMissing Negative(gcoff)
2751 Generate debug information in extended XCOFF format.
2754 Name(compressed_debug_sections) Type(int)
2756 ; Since -gz= is completely handled in specs, the values aren't used and we
2757 ; assign arbitrary constants.
2759 Enum(compressed_debug_sections) String(none) Value(0)
2762 Enum(compressed_debug_sections) String(zlib) Value(1)
2765 Enum(compressed_debug_sections) String(zlib-gnu) Value(2)
2769 Generate compressed debug sections.
2772 Common Driver Joined Enum(compressed_debug_sections)
2773 -gz=<format> Generate compressed debug sections in format <format>.
2776 Driver Joined Separate
2779 Common Joined Var(plugindir_string) Init(0)
2780 -iplugindir=<dir> Set <dir> to be the default plugin directory.
2783 Common Joined Separate RejectDriver Var(imultiarch) Init(0)
2784 -imultiarch <dir> Set <dir> to be the multiarch include subdirectory.
2787 Driver Joined Separate
2792 no-canonical-prefixes
2805 Common Driver Joined Separate Var(asm_file_name) MissingArgError(missing filename after %qs)
2806 -o <file> Place output into <file>.
2809 Common Var(profile_flag)
2810 Enable function profiling.
2813 Driver Var(pass_exit_codes)
2816 Common Alias(Wpedantic)
2819 Common Var(flag_pedantic_errors)
2820 Like -pedantic but issue them as errors.
2826 Driver Var(use_pipes)
2829 Driver JoinedOrMissing Var(print_file_name)
2831 print-libgcc-file-name
2834 print-multi-directory
2835 Driver Var(print_multi_directory)
2838 Driver Var(print_multi_lib)
2840 print-multi-os-directory
2841 Driver Var(print_multi_os_directory)
2844 Driver Var(print_multiarch)
2847 Driver JoinedOrMissing Var(print_prog_name)
2850 Driver Var(print_search_dirs)
2853 Driver Var(print_sysroot)
2855 print-sysroot-headers-suffix
2856 Driver Var(print_sysroot_headers_suffix)
2859 Common Var(quiet_flag) RejectDriver
2860 Do not display functions compiled or elapsed time.
2878 Driver Var(report_times)
2881 Driver JoinedOrMissing
2884 Driver Joined Separate
2888 ; C option, but driver must not handle as "-u ndef".
2891 Common Driver Var(verbose_flag)
2892 Enable verbose output.
2895 Common Var(version_flag) RejectDriver
2896 Display the compiler's version.
2899 Common Var(inhibit_warnings)
2903 Driver Separate Var(wrapper_string)
2906 Driver Joined Separate
2909 Driver RejectNegative Negative(pie)
2910 Create a shared library.
2916 Driver Separate Alias(specs=)
2929 ; Documented for Fortran, but always accepted by driver.
2936 ; Documented for Go, but always accepted by driver.
2954 Driver RejectNegative Negative(shared)
2955 Don't create a position independent executable.
2958 Driver RejectNegative Negative(no-pie)
2959 Create a position independent executable.
2962 Driver Joined Separate
2965 Common Report Var(flag_ipa_ra) Optimization
2966 Use caller save register across calls if possible.
2968 ; This comment is to ensure we retain the blank line above.