1 ; Options for the C, ObjC, C++ and ObjC++ front ends.
2 ; Copyright (C) 2003-2014 Free Software Foundation, Inc.
4 ; This file is part of GCC.
6 ; GCC is free software; you can redistribute it and/or modify it under
7 ; the terms of the GNU General Public License as published by the Free
8 ; Software Foundation; either version 3, or (at your option) any later
11 ; GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 ; WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 ; FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
16 ; You should have received a copy of the GNU General Public License
17 ; along with GCC; see the file COPYING3. If not see
18 ; <http://www.gnu.org/licenses/>.
20 ; See the GCC internals manual for a description of this file's format.
22 ; Please try to keep this file in ASCII collating order.
37 C ObjC C++ ObjC++ Warning Alias(Wall)
40 C ObjC C++ ObjC++ Alias(ansi)
43 C ObjC C++ ObjC++ Separate Alias(A) MissingArgError(assertion missing after %qs)
46 C ObjC C++ ObjC++ Joined Alias(A) MissingArgError(assertion missing after %qs)
49 C ObjC C++ ObjC++ Alias(C)
52 C ObjC C++ ObjC++ Alias(CC)
55 C ObjC C++ ObjC++ Separate Alias(D) MissingArgError(macro name missing after %qs)
58 C ObjC C++ ObjC++ Joined Alias(D) MissingArgError(macro name missing after %qs)
61 C ObjC C++ ObjC++ Alias(M)
64 C ObjC C++ ObjC++ Separate Alias(d)
67 C ObjC C++ ObjC++ Joined Alias(d)
70 C ObjC C++ ObjC++ Separate Alias(imacros) MissingArgError(missing filename after %qs)
73 C ObjC C++ ObjC++ Joined Alias(imacros) MissingArgError(missing filename after %qs)
76 C ObjC C++ ObjC++ Separate Alias(include) MissingArgError(missing filename after %qs)
79 C ObjC C++ ObjC++ Joined Alias(include) MissingArgError(missing filename after %qs)
82 C ObjC C++ ObjC++ Alias(I, -)
85 C ObjC C++ ObjC++ Separate Alias(I) MissingArgError(missing path after %qs)
88 C ObjC C++ ObjC++ Joined Alias(I) MissingArgError(missing path after %qs)
90 -include-directory-after
91 C ObjC C++ ObjC++ Separate Alias(idirafter) MissingArgError(missing path after %qs)
93 -include-directory-after=
94 C ObjC C++ ObjC++ Joined Alias(idirafter) MissingArgError(missing path after %qs)
97 C ObjC C++ ObjC++ Separate Alias(iprefix)
100 C ObjC C++ ObjC++ JoinedOrMissing Alias(iprefix)
103 C ObjC C++ ObjC++ Separate Alias(iwithprefix)
105 -include-with-prefix=
106 C ObjC C++ ObjC++ JoinedOrMissing Alias(iwithprefix)
108 -include-with-prefix-after
109 C ObjC C++ ObjC++ Separate Alias(iwithprefix)
111 -include-with-prefix-after=
112 C ObjC C++ ObjC++ JoinedOrMissing Alias(iwithprefix)
114 -include-with-prefix-before
115 C ObjC C++ ObjC++ Separate Alias(iwithprefixbefore)
117 -include-with-prefix-before=
118 C ObjC C++ ObjC++ JoinedOrMissing Alias(iwithprefixbefore)
121 Driver Alias(no-integrated-cpp)
124 C ObjC C++ ObjC++ Alias(P)
126 -no-standard-includes
127 C ObjC C++ ObjC++ Alias(nostdinc)
130 C ObjC C++ ObjC++ Alias(w)
133 C ObjC C++ ObjC++ Separate Alias(o)
136 C ObjC C++ ObjC++ Joined Alias(o)
139 C ObjC C++ ObjC++ Joined Separate
142 C ObjC C++ ObjC++ Alias(pedantic)
145 C ObjC C++ ObjC++ Undocumented Alias(E)
147 -print-missing-file-dependencies
148 C ObjC C++ ObjC++ Alias(MG)
151 C ObjC C++ ObjC++ Alias(H)
154 Driver Alias(traditional)
157 C ObjC C++ ObjC++ Alias(traditional-cpp)
160 C ObjC C++ ObjC++ Alias(trigraphs)
163 C ObjC C++ ObjC++ Separate Alias(U) MissingArgError(macro name missing after %qs)
166 C ObjC C++ ObjC++ Joined Alias(U) MissingArgError(macro name missing after %qs)
169 C ObjC C++ ObjC++ Alias(MM)
172 Common C ObjC C++ ObjC++ Alias(v)
175 C ObjC C++ ObjC++ NoDriverArg Separate Alias(MD) MissingArgError(missing filename after %qs)
177 -write-user-dependencies
178 C ObjC C++ ObjC++ NoDriverArg Separate Alias(MMD) MissingArgError(missing filename after %qs)
181 C ObjC C++ ObjC++ Joined Separate MissingArgError(assertion missing after %qs)
182 -A<question>=<answer> Assert the <answer> to <question>. Putting '-' before <question> disables the <answer> to <question>
186 Do not discard comments
190 Do not discard comments in macro expansions
193 C ObjC C++ ObjC++ Joined Separate MissingArgError(macro name missing after %qs)
194 -D<macro>[=<val>] Define a <macro> with <val> as its value. If just <macro> is given, <val> is taken to be 1
197 C ObjC C++ ObjC++ Undocumented Var(flag_preprocess_only)
200 Driver C ObjC C++ ObjC++ Joined Separate MissingArgError(missing path after %qs)
201 -F <dir> Add <dir> to the end of the main framework include path
205 Print the name of header files as they are used
208 C ObjC C++ ObjC++ Joined Separate MissingArgError(missing path after %qs)
209 -I <dir> Add <dir> to the end of the main include path
213 Generate make dependencies
216 C ObjC C++ ObjC++ NoDriverArg Separate MissingArgError(missing filename after %qs)
217 Generate make dependencies and compile
220 C ObjC C++ ObjC++ Joined Separate MissingArgError(missing filename after %qs)
221 -MF <file> Write dependency output to the given file
225 Treat missing header files as generated files
229 Like -M but ignore system header files
232 C ObjC C++ ObjC++ NoDriverArg Separate MissingArgError(missing filename after %qs)
233 Like -MD but ignore system header files
237 Generate phony targets for all headers
240 C ObjC C++ ObjC++ Joined Separate MissingArgError(missing makefile target after %qs)
241 -MQ <target> Add a MAKE-quoted target
244 C ObjC C++ ObjC++ Joined Separate MissingArgError(missing makefile target after %qs)
245 -MT <target> Add an unquoted target
249 Do not generate #line directives
252 C ObjC C++ ObjC++ Joined Separate MissingArgError(macro name missing after %qs)
253 -U<macro> Undefine <macro>
256 C ObjC C++ ObjC++ LTO Var(warn_abi) Warning
257 Warn about things that will change when compiling with an ABI-compliant compiler
260 C++ ObjC++ Var(warn_abi_tag) Warning
261 Warn if a subobject has an abi_tag attribute that the complete object type does not have
264 C ObjC C++ ObjC++ LTO Var(warn_psabi) Init(1) Undocumented
267 C ObjC C++ ObjC++ Var(warn_address) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall)
268 Warn about suspicious uses of memory addresses
271 C ObjC C++ ObjC++ Warning
272 Enable most warning messages
275 LangEnabledBy(C ObjC C++ ObjC++,Wall)
279 ObjC ObjC++ Var(warn_assign_intercept) Warning
280 Warn whenever an Objective-C assignment is being intercepted by the garbage collector
283 C ObjC Var(warn_bad_function_cast) Warning
284 Warn about casting functions to incompatible types
286 Wbuiltin-macro-redefined
287 C ObjC C++ ObjC++ Warning
288 Warn when a built-in preprocessor macro is undefined or redefined
291 C ObjC Var(warn_cxx_compat) Warning
292 Warn about C constructs that are not in the common subset of C and C++
295 C++ ObjC++ Var(warn_cxx0x_compat) Warning LangEnabledBy(C++ ObjC++,Wall)
296 Deprecated in favor of -Wc++11-compat
299 C++ ObjC++ Warning Alias(Wc++0x-compat)
300 Warn about C++ constructs whose meaning differs between ISO C++ 1998 and ISO C++ 2011
303 C ObjC C++ ObjC++ Var(warn_cast_qual) Warning
304 Warn about casts which discard qualifiers
307 C ObjC C++ ObjC++ Var(warn_char_subscripts) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall)
308 Warn about subscripts whose type is \"char\"
311 C ObjC C++ ObjC++ Var(warn_clobbered) Warning EnabledBy(Wextra)
312 Warn about variables that might be changed by \"longjmp\" or \"vfork\"
315 C ObjC C++ ObjC++ Warning
316 Warn about possibly nested block comments, and C++ comments spanning more than one physical line
319 C ObjC C++ ObjC++ Warning Alias(Wcomment)
320 Synonym for -Wcomment
322 Wconditionally-supported
323 C++ ObjC++ Var(warn_conditionally_supported) Warning
324 Warn for conditionally-supported constructs
327 C ObjC C++ ObjC++ Var(warn_conversion) Warning
328 Warn for implicit type conversions that may change a value
331 C++ ObjC++ Var(warn_conversion_null) Init(1) Warning
332 Warn for converting NULL from/to a non-pointer type
335 C++ ObjC++ Var(warn_ctor_dtor_privacy) Warning
336 Warn when all constructors and destructors are private
338 Wdeclaration-after-statement
339 C ObjC Var(warn_declaration_after_statement) Warning
340 Warn when a declaration is found after a statement
343 C++ ObjC++ Var(warn_delete_incomplete) Init(1) Warning
344 Warn when deleting a pointer to incomplete type
346 Wdelete-non-virtual-dtor
347 C++ ObjC++ Var(warn_delnonvdtor) Warning LangEnabledBy(C++ ObjC++,Wall)
348 Warn about deleting polymorphic objects with non-virtual destructors
350 Wdelete-non-virtual-dtor
351 LangEnabledBy(C++ ObjC++,Weffc++)
355 C C++ ObjC ObjC++ Var(warn_deprecated) Init(1) Warning
356 Warn if a deprecated compiler feature, class, method, or field is used
359 C ObjC C++ ObjC++ Var(warn_div_by_zero) Init(1) Warning
360 Warn about compile-time integer division by zero
363 C++ ObjC++ Var(warn_ecpp) Warning
364 Warn about violations of Effective C++ style rules
367 C ObjC C++ ObjC++ Var(warn_empty_body) Warning EnabledBy(Wextra)
368 Warn about an empty body in an if or else statement
371 C ObjC C++ ObjC++ Warning
372 Warn about stray tokens after #elif and #endif
375 C ObjC C++ ObjC++ Var(warn_enum_compare) Init(-1) Warning LangEnabledBy(C ObjC,Wall)
376 Warn about comparison of different enum types
379 LangEnabledBy(C ObjC,Wc++-compat)
384 ; Documented in common.opt
386 Werror-implicit-function-declaration
387 C ObjC RejectNegative Warning Alias(Werror=, implicit-function-declaration)
388 This switch is deprecated; use -Werror=implicit-function-declaration instead
391 C ObjC C++ ObjC++ Var(warn_float_conversion) LangEnabledBy(C ObjC C++ ObjC++,Wconversion)
392 Warn for implicit type conversions that cause loss of floating point precision
395 C ObjC C++ ObjC++ Var(warn_float_equal) Warning
396 Warn if testing floating point numbers for equality
399 C ObjC C++ ObjC++ Warning Alias(Wformat=, 1, 0)
400 Warn about printf/scanf/strftime/strfmon format string anomalies
403 C ObjC C++ ObjC++ Var(warn_format_contains_nul) Warning LangEnabledBy(C ObjC C++ ObjC++,Wformat=, warn_format >= 1, 0)
404 Warn about format strings that contain NUL bytes
407 C ObjC C++ ObjC++ Var(warn_format_extra_args) Warning LangEnabledBy(C ObjC C++ ObjC++,Wformat=, warn_format >= 1, 0)
408 Warn if passing too many arguments to a function for its format string
411 C ObjC C++ ObjC++ Var(warn_format_nonliteral) Warning LangEnabledBy(C ObjC C++ ObjC++,Wformat=, warn_format >= 2, 0)
412 Warn about format strings that are not literals
415 C ObjC C++ ObjC++ Var(warn_format_security) Warning LangEnabledBy(C ObjC C++ ObjC++,Wformat=, warn_format >= 2, 0)
416 Warn about possible security problems with format functions
419 C ObjC C++ ObjC++ Var(warn_format_signedness) Warning LangEnabledBy(C ObjC C++ ObjC++,Wformat=, warn_format >= 2, 0)
420 Warn about sign differences with format functions
423 C ObjC C++ ObjC++ Var(warn_format_y2k) Warning LangEnabledBy(C ObjC C++ ObjC++,Wformat=,warn_format >= 2, 0)
424 Warn about strftime formats yielding 2-digit years
427 C ObjC C++ ObjC++ Var(warn_format_zero_length) Warning LangEnabledBy(C ObjC C++ ObjC++,Wformat=,warn_format >= 1, 0)
428 Warn about zero-length formats
431 C ObjC C++ ObjC++ Joined RejectNegative UInteger Var(warn_format) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall, 1, 0)
432 Warn about printf/scanf/strftime/strfmon format string anomalies
435 C C++ Var(warn_ignored_qualifiers) Warning EnabledBy(Wextra)
436 Warn whenever type qualifiers are ignored.
439 C ObjC C++ ObjC++ Var(warn_init_self) Warning LangEnabledBy(C++ ObjC++,Wall)
440 Warn about variables which are initialized to themselves
443 C ObjC Var(warn_implicit) Warning LangEnabledBy(C ObjC,Wall)
444 Warn about implicit declarations
447 C ObjC C++ ObjC++ Var(warn_double_promotion) Warning
448 Warn about implicit conversions from \"float\" to \"double\"
450 Wimplicit-function-declaration
451 C ObjC Var(warn_implicit_function_declaration) Init(-1) Warning LangEnabledBy(C ObjC,Wimplicit)
452 Warn about implicit function declarations
455 C ObjC Var(warn_implicit_int) Warning LangEnabledBy(C ObjC,Wimplicit)
456 Warn when a declaration does not specify a type
459 C ObjC C++ ObjC++ Undocumented Ignore
461 Winherited-variadic-ctor
462 C++ ObjC++ Var(warn_inh_var_ctor) Init(1) Warning
463 Warn about C++11 inheriting constructors when the base has a variadic constructor
466 C ObjC C++ ObjC++ Var(warn_int_to_pointer_cast) Init(1) Warning
467 Warn when there is a cast to a pointer from an integer of a different size
470 C++ ObjC++ Var(warn_invalid_offsetof) Init(1) Warning
471 Warn about invalid uses of the \"offsetof\" macro
474 C ObjC C++ ObjC++ Warning
475 Warn about PCH files that are found but not used
478 C ObjC Var(warn_jump_misses_init) Warning LangEnabledby(C ObjC,Wc++-compat)
479 Warn when a jump misses a variable initialization
483 Warn when a string or character literal is followed by a ud-suffix which does not begin with an underscore.
486 C ObjC C++ ObjC++ Var(warn_logical_op) Init(0) Warning
487 Warn when a logical operator is suspiciously always evaluating to true or false
490 C ObjC C++ ObjC++ Var(warn_long_long) Init(-1) Warning
491 Do not warn about using \"long long\" when -pedantic
494 C ObjC C++ ObjC++ Var(warn_main) Init(-1) Warning LangEnabledBy(C ObjC,Wall, 2, 0)
495 Warn about suspicious declarations of \"main\"
498 LangEnabledBy(C ObjC C++ ObjC++,Wpedantic, 2, 0)
502 C ObjC C++ ObjC++ Var(warn_missing_braces) Warning LangEnabledBy(C ObjC,Wall)
503 Warn about possibly missing braces around initializers
505 Wmissing-declarations
506 C ObjC C++ ObjC++ Var(warn_missing_declarations) Warning
507 Warn about global functions without previous declarations
509 Wmissing-field-initializers
510 C ObjC C++ ObjC++ Var(warn_missing_field_initializers) Warning EnabledBy(Wextra)
511 Warn about missing fields in struct initializers
513 Wsizeof-pointer-memaccess
514 C ObjC C++ ObjC++ Var(warn_sizeof_pointer_memaccess) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall)
516 Wsuggest-attribute=format
517 C ObjC C++ ObjC++ Var(warn_suggest_attribute_format) Warning
518 Warn about functions which might be candidates for format attributes
521 C ObjC C++ ObjC++ Var(warn_switch) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall)
522 Warn about enumerated switches, with no default, missing a case
525 C ObjC C++ ObjC++ Var(warn_switch_default) Warning
526 Warn about enumerated switches missing a \"default:\" statement
529 C ObjC C++ ObjC++ Var(warn_switch_enum) Warning
530 Warn about all enumerated switches missing a specific case
532 Wmissing-format-attribute
533 C ObjC C++ ObjC++ Alias(Wsuggest-attribute=format)
536 Wmissing-include-dirs
537 C ObjC C++ ObjC++ Warning
538 Warn about user-specified include directories that do not exist
540 Wmissing-parameter-type
541 C ObjC Var(warn_missing_parameter_type) Warning EnabledBy(Wextra)
542 Warn about function parameters declared without a type specifier in K&R-style functions
545 C ObjC Var(warn_missing_prototypes) Warning
546 Warn about global functions without prototypes
549 C ObjC C++ ObjC++ Ignore Warn(switch %qs is no longer supported)
552 C ObjC C++ ObjC++ Warning
553 Warn about use of multi-character character constants
556 C ObjC C++ ObjC++ Warning Var(warn_narrowing) Init(-1) LangEnabledBy(C++ ObjC++,Wall)
557 Warn about narrowing conversions within { } that are ill-formed in C++11
560 C ObjC C++ ObjC++ LangEnabledBy(C++ ObjC++,Wc++0x-compat)
564 C ObjC Var(warn_nested_externs) Warning
565 Warn about \"extern\" declarations not at file scope
568 C++ ObjC++ Var(warn_noexcept) Warning
569 Warn when a noexcept expression evaluates to false even though the expression can't actually throw
572 C++ ObjC++ Var(warn_nontemplate_friend) Init(1) Warning
573 Warn when non-templatized friend functions are declared within a template
576 C++ ObjC++ Var(warn_nonvdtor) Warning LangEnabledBy(C++ ObjC++,Weffc++)
577 Warn about non-virtual destructors
580 C ObjC C++ ObjC++ Var(warn_nonnull) Warning LangEnabledBy(C ObjC C++ ObjC++,Wformat=,warn_format >= 1,0)
581 Warn about NULL being passed to argument slots marked as requiring non-NULL
584 C ObjC C++ ObjC++ LangEnabledBy(C ObjC C++ ObjC++,Wall)
588 C ObjC C++ ObjC++ Joined Warning
589 -Wnormalized=<id|nfc|nfkc> Warn about non-normalised Unicode strings
592 C++ ObjC++ Var(warn_old_style_cast) Warning
593 Warn if a C-style cast is used in a program
595 Wold-style-declaration
596 C ObjC Var(warn_old_style_declaration) Warning EnabledBy(Wextra)
597 Warn for obsolescent usage in a declaration
599 Wold-style-definition
600 C ObjC Var(warn_old_style_definition) Warning
601 Warn if an old-style parameter definition is used
604 C C++ Var(warn_openmp_simd) Warning LangEnabledBy(C C++,Wall)
605 Warn if a simd directive is overridden by the vectorizer cost model
608 C ObjC C++ ObjC++ Var(warn_overlength_strings) Warning LangEnabledBy(C ObjC C++ ObjC++,Wpedantic)
609 Warn if a string is longer than the maximum portable length specified by the standard
612 C++ ObjC++ Var(warn_overloaded_virtual) Warning
613 Warn about overloaded virtual function names
616 C ObjC Var(warn_override_init) Warning EnabledBy(Wextra)
617 Warn about overriding initializers without side effects
619 Wpacked-bitfield-compat
620 C ObjC C++ ObjC++ Var(warn_packed_bitfield_compat) Init(-1) Warning
621 Warn about packed bit-fields whose offset changed in GCC 4.4
624 C ObjC C++ ObjC++ Var(warn_parentheses) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall)
625 Warn about possibly missing parentheses
628 C ObjC C++ ObjC++ Warning
629 ; Documented in common.opt
632 C++ ObjC++ Var(warn_pmf2ptr) Init(1) Warning
633 Warn when converting the type of pointers to member functions
636 C ObjC C++ ObjC++ Var(warn_pointer_arith) Warning LangEnabledBy(C ObjC C++ ObjC++,Wpedantic)
637 Warn about function pointer arithmetic
640 C ObjC Var(warn_pointer_sign) Warning LangEnabledBy(C ObjC,Wall)
641 Warn when a pointer differs in signedness in an assignment
644 C ObjC LangEnabledBy(C ObjC,Wpedantic)
648 C ObjC Var(warn_pointer_to_int_cast) Init(1) Warning
649 Warn when a pointer is cast to an integer of a different size
652 C ObjC C++ ObjC++ Var(warn_pragmas) Init(1) Warning
653 Warn about misuses of pragmas
656 Common Var(cpp_warn_date_time) Warning
657 Warn about __TIME__, __DATE__ and __TIMESTAMP__ usage
659 Wproperty-assign-default
660 ObjC ObjC++ Var(warn_property_assign_default) Init(1) Warning
661 Warn if a property for an Objective-C object has no assign semantics specified
664 ObjC ObjC++ Var(warn_protocol) Init(1) Warning
665 Warn if inherited methods are unimplemented
668 C ObjC C++ ObjC++ Var(warn_redundant_decls) Warning
669 Warn about multiple declarations of the same object
672 C++ ObjC++ Var(warn_reorder) Warning LangEnabledBy(C++ ObjC++,Wall)
673 Warn when the compiler reorders code
676 C ObjC C++ ObjC++ Var(warn_return_local_addr) Init(1) Warning
677 Warn about returning a pointer/reference to a local or temporary variable.
680 C ObjC C++ ObjC++ Var(warn_return_type) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall)
681 Warn whenever a function's return type defaults to \"int\" (C), or about inconsistent return types (C++)
684 ObjC ObjC++ Var(warn_selector) Warning
685 Warn if a selector has multiple methods
688 C ObjC C++ ObjC++ Var(warn_sequence_point) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall)
689 Warn about possible violations of sequence point rules
692 C ObjC C++ ObjC++ Var(warn_sign_compare) Warning LangEnabledBy(C++ ObjC++,Wall)
693 Warn about signed-unsigned comparisons
696 C ObjC C++ ObjC++ EnabledBy(Wextra)
700 C ObjC C++ ObjC++ Var(warn_sign_conversion) LangEnabledBy(C ObjC,Wconversion)
701 Warn for implicit type conversions between signed and unsigned integers
704 C++ ObjC++ Var(warn_sign_promo) Warning
705 Warn when overload promotes from unsigned to signed
707 Wstrict-null-sentinel
708 C++ ObjC++ Warning Var(warn_strict_null_sentinel)
709 Warn about uncasted NULL used as sentinel
712 C ObjC Var(warn_strict_prototypes) Warning
713 Warn about unprototyped function declarations
716 C ObjC C++ ObjC++ LangEnabledBy(C ObjC C++ ObjC++,Wall, 3, 0)
720 C ObjC C++ ObjC++ LangEnabledBy(C ObjC C++ ObjC++,Wall, 1, 0)
723 Wstrict-selector-match
724 ObjC ObjC++ Var(warn_strict_selector_match) Warning
725 Warn if type signatures of candidate methods do not match exactly
728 C C++ Var(warn_sync_nand) Init(1) Warning
729 Warn when __sync_fetch_and_nand and __sync_nand_and_fetch built-in functions are used
732 C++ ObjC++ Var(warn_synth) Warning
733 Deprecated. This switch has no effect
736 C ObjC C++ ObjC++ Warning
737 ; Documented in common.opt
740 C ObjC Var(warn_traditional) Warning
741 Warn about features not present in traditional C
743 Wtraditional-conversion
744 C ObjC Var(warn_traditional_conversion) Warning
745 Warn of prototypes causing type conversions different from what would happen in the absence of prototype
748 C ObjC C++ ObjC++ Warning
749 Warn if trigraphs are encountered that might affect the meaning of the program
752 ObjC ObjC++ Var(warn_undeclared_selector) Warning
753 Warn about @selector()s without previously declared methods
756 C ObjC C++ ObjC++ Warning
757 Warn if an undefined macro is used in an #if directive
760 C ObjC C++ ObjC++ LangEnabledBy(C ObjC C++ ObjC++,Wall)
764 C ObjC C++ ObjC++ LangEnabledBy(C ObjC C++ ObjC++,Wall)
768 C ObjC C++ ObjC++ Warning Var(warn_unknown_pragmas) LangEnabledBy(C ObjC C++ ObjC++,Wall, 1, 0)
769 Warn about unrecognized pragmas
771 Wunsuffixed-float-constants
772 C ObjC Var(warn_unsuffixed_float_constants) Warning
773 Warn about unsuffixed float constants
776 C ObjC C++ ObjC++ LangEnabledBy(C ObjC C++ ObjC++,Wall)
777 ; documented in common.opt
779 Wunused-local-typedefs
780 C ObjC C++ ObjC++ Var(warn_unused_local_typedefs) Warning EnabledBy(Wunused)
781 Warn when typedefs locally defined in a function are not used
784 C ObjC C++ ObjC++ Var(cpp_warn_unused_macros) Warning
785 Warn about macros defined in the main file that are not used
788 C ObjC C++ ObjC++ Var(warn_unused_result) Init(1) Warning
789 Warn if a caller of a function, marked with attribute warn_unused_result, does not use its return value
792 C ObjC C++ ObjC++ Var(cpp_warn_variadic_macros) Init(1) Warning
793 Warn about using variadic macros
796 C ObjC C++ ObjC++ Warning Var(warn_varargs) Init(1)
797 Warn about questionable usage of the macros used to retrieve variable arguments
800 C ObjC C++ ObjC++ Var(warn_vla) Init(-1) Warning
801 Warn if a variable length array is used
803 Wvolatile-register-var
804 C ObjC C++ ObjC++ Var(warn_volatile_register_var) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall)
805 Warn when a register variable is declared volatile
808 C++ ObjC++ Var(warn_virtual_move_assign) Warning Init(1)
809 Warn if a virtual base has a non-trivial move assignment operator
812 C ObjC C++ ObjC++ Var(warn_write_strings) Warning
813 In C++, nonzero means warn about deprecated conversion from string literals to 'char *'. In C, similar warning, except that the conversion is of course not deprecated by the ISO C standard.
815 Wzero-as-null-pointer-constant
816 C++ ObjC++ Var(warn_zero_as_null_pointer_constant) Warning
817 Warn when a literal '0' is used as null pointer
820 C++ ObjC++ Var(warn_useless_cast) Warning
821 Warn about useless casts
825 A synonym for -std=c89 (for C) or -std=c++98 (for C++)
828 C ObjC C++ ObjC++ Joined
829 ; Documented in common.opt. FIXME - what about -dI, -dD, -dN and -dD?
832 C++ ObjC++ Var(flag_access_control) Init(1)
833 Enforce class member access control semantics
836 C ObjC C++ ObjC++ RejectNegative Joined Var(ada_specs_parent)
837 -fada-spec-parent=unit Dump Ada specs as child units of given parent
840 C++ ObjC++ Ignore Warn(switch %qs is no longer supported)
842 fallow-parameterless-variadic-functions
843 C ObjC Var(flag_allow_parameterless_variadic_functions)
844 Allow variadic functions without named parameter
846 falt-external-templates
847 C++ ObjC++ Ignore Warn(switch %qs is no longer supported)
851 C ObjC C++ ObjC++ Var(flag_no_asm, 0)
852 Recognize the \"asm\" keyword
854 ; Define extra predefined macros for use in libgcc.
856 C ObjC C++ ObjC++ Undocumented Var(flag_building_libgcc)
859 C ObjC C++ ObjC++ Var(flag_no_builtin, 0)
860 Recognize built-in functions
863 C ObjC C++ ObjC++ Joined
865 fcanonical-system-headers
867 Where shorter, use canonicalized paths to systems headers.
870 C ObjC C++ ObjC++ LTO Report Var(flag_cilkplus) Init(0)
875 Allow the arguments of the '?' operator to have different types
878 C++ ObjC++ Var(flag_conserve_space)
879 Does nothing. Preserved for backward compatibility.
881 fconstant-string-class=
882 ObjC ObjC++ Joined MissingArgError(no class name specified with %qs)
883 -fconst-string-class=<name> Use class <name> for constant strings
886 C++ ObjC++ Joined RejectNegative UInteger Var(max_constexpr_depth) Init(512)
887 -fconstexpr-depth=<number> Specify maximum constexpr recursion depth
891 Emit debug annotations during preprocessing
894 C++ ObjC++ Var(flag_deduce_init_list) Init(0)
895 -fdeduce-init-list enable deduction of std::initializer_list for a template type parameter from a brace-enclosed initializer-list
898 C++ ObjC++ Var(flag_declone_ctor_dtor) Init(-1)
899 Factor complex constructors and destructors to favor space over speed
903 Does nothing. Preserved for backward compatibility.
907 Preprocess directives only.
909 fdollars-in-identifiers
911 Permit '$' as an identifier character
914 C ObjC C++ ObjC++ RejectNegative Var(flag_dump_ada_spec)
915 Write all declarations as Ada code transitively
918 C ObjC C++ ObjC++ RejectNegative Var(flag_dump_ada_spec_slim)
919 Write all declarations as Ada code for the given file only
922 C++ ObjC++ Var(flag_elide_constructors) Init(1)
925 C++ ObjC++ Var(flag_enforce_eh_specs) Init(1)
926 Generate code to check exception specifications
929 C++ ObjC++ Ignore Warn(switch %qs is no longer supported)
932 C ObjC C++ ObjC++ Joined RejectNegative
933 -fexec-charset=<cset> Convert all strings and character constants to character set <cset>
935 fextended-identifiers
937 Permit universal character names (\\u and \\U) in identifiers
940 C ObjC C++ ObjC++ Joined RejectNegative
941 -finput-charset=<cset> Specify the default character set for source files
944 C++ ObjC++ Var(flag_extern_tls_init) Init(-1)
945 Support dynamic initialization of thread-local variables in a different translation unit
948 C++ ObjC++ Ignore Warn(switch %qs is no longer supported)
951 C++ ObjC++ Var(flag_new_for_scope) Init(1)
952 Scope of for-init-statement variables is local to the loop
956 Do not assume that standard C libraries and \"main\" exist
959 C++ ObjC++ Var(flag_no_gnu_keywords, 0)
960 Recognize GNU-defined keywords
963 ObjC ObjC++ LTO Report RejectNegative Var(flag_next_runtime,0) Init(NEXT_OBJC_RUNTIME)
964 Generate code for GNU runtime environment
967 C ObjC Var(flag_gnu89_inline) Init(-1)
968 Use traditional GNU semantics for inline functions
971 C++ ObjC++ Ignore Warn(switch %qs is no longer supported)
974 C++ ObjC++ Optimization Alias(fexceptions) Warn({-fhandle-exceptions has been renamed -fexceptions (and is now on by default)})
977 C++ ObjC++ Ignore Warn(switch %qs is no longer supported)
981 Assume normal C execution environment
984 C++ ObjC++ Ignore Warn(switch %qs is no longer supported)
988 C++ ObjC++ Var(flag_implement_inlines) Init(1)
989 Export functions even if they can be inlined
991 fimplicit-inline-templates
992 C++ ObjC++ Var(flag_implicit_inline_templates) Init(1)
993 Emit implicit instantiations of inline templates
996 C++ ObjC++ Var(flag_implicit_templates) Init(1)
997 Emit implicit instantiations of templates
1000 C++ ObjC++ Var(flag_friend_injection)
1001 Inject friend functions into enclosing namespace
1003 fkeep-inline-dllexport
1004 C C++ ObjC ObjC++ Var(flag_keep_inline_dllexport) Init(1) Report Condition(TARGET_DLLIMPORT_DECL_ATTRIBUTES)
1005 Don't emit dllexported inline functions unless needed
1008 C++ ObjC++ Ignore Warn(switch %qs is no longer supported)
1010 flax-vector-conversions
1011 C ObjC C++ ObjC++ Var(flag_lax_vector_conversions)
1012 Allow implicit conversions between vectors with differing numbers of subparts and/or differing element types.
1015 C ObjC C++ ObjC++ Var(flag_ms_extensions)
1016 Don't warn about uses of Microsoft extensions
1019 C ObjC C++ ObjC++ Ignore Warn(switch %qs is no longer supported)
1022 C ObjC C++ ObjC++ Ignore Warn(switch %qs is no longer supported)
1025 C ObjC C++ ObjC++ Ignore Warn(switch %qs is no longer supported)
1027 fname-mangling-version-
1028 C++ ObjC++ Joined Ignore Warn(switch %qs is no longer supported)
1031 C++ ObjC++ Ignore Warn(switch %qs is no longer supported)
1034 ObjC ObjC++ LTO Report RejectNegative Var(flag_next_runtime)
1035 Generate code for NeXT (Apple Mac OS X) runtime environment
1038 ObjC ObjC++ Var(flag_nil_receivers) Init(1)
1039 Assume that receivers of Objective-C messages may be nil
1042 C++ ObjC++ Var(flag_no_nonansi_builtin, 0)
1045 C++ ObjC++ Ignore Warn(switch %qs is no longer supported)
1048 C++ ObjC++ Optimization Var(flag_nothrow_opt)
1049 Treat a throw() exception specification as noexcept to improve code size
1052 ObjC ObjC++ LTO Joined Report RejectNegative UInteger Var(flag_objc_abi)
1053 Specify which ABI to use for Objective-C family code and meta-data generation.
1055 ; Generate special '- .cxx_construct' and '- .cxx_destruct' methods
1056 ; to initialize any non-POD ivars in Objective-C++ classes.
1057 fobjc-call-cxx-cdtors
1058 ObjC++ Var(flag_objc_call_cxx_cdtors)
1059 Generate special Objective-C methods to initialize/destroy non-POD C++ ivars, if needed
1061 fobjc-direct-dispatch
1062 ObjC ObjC++ Var(flag_objc_direct_dispatch)
1063 Allow fast jumps to the message dispatcher
1065 ; Nonzero means that we will allow new ObjC exception syntax (@throw,
1066 ; @try, etc.) in source code.
1068 ObjC ObjC++ Var(flag_objc_exceptions)
1069 Enable Objective-C exception and synchronization syntax
1072 ObjC ObjC++ LTO Var(flag_objc_gc)
1073 Enable garbage collection (GC) in Objective-C/Objective-C++ programs
1076 ObjC ObjC++ Var(flag_objc_nilcheck,1)
1077 Enable inline checks for nil receivers with the NeXT runtime and ABI version 2.
1079 ; Nonzero means that we generate NeXT setjmp based exceptions.
1080 fobjc-sjlj-exceptions
1081 ObjC ObjC++ Var(flag_objc_sjlj_exceptions) Init(-1)
1082 Enable Objective-C setjmp exception handling runtime
1085 ObjC ObjC++ Var(flag_objc1_only)
1086 Conform to the Objective-C 1.0 language as implemented in GCC 4.0
1089 C ObjC C++ ObjC++ Var(flag_openmp)
1090 Enable OpenMP (implies -frecursive in Fortran)
1093 C ObjC C++ ObjC++ Var(flag_openmp_simd)
1094 Enable OpenMP's SIMD directives
1098 Recognize C++ keywords like \"compl\" and \"xor\"
1102 Does nothing. Preserved for backward compatibility.
1109 Look for and use PCH files even when preprocessing
1112 C++ ObjC++ Var(flag_permissive)
1113 Downgrade conformance errors to warnings
1116 C ObjC Var(flag_plan9_extensions)
1117 Enable Plan 9 language extensions
1121 Treat the input file as already preprocessed
1123 ftrack-macro-expansion
1124 C ObjC C++ ObjC++ JoinedOrMissing RejectNegative UInteger
1125 ; converted into ftrack-macro-expansion=
1127 ftrack-macro-expansion=
1128 C ObjC C++ ObjC++ JoinedOrMissing RejectNegative UInteger
1129 -ftrack-macro-expansion=<0|1|2> Track locations of tokens coming from macro expansion and display them in error messages
1132 C++ ObjC++ Var(flag_pretty_templates) Init(1)
1133 -fno-pretty-templates Do not pretty-print template specializations as the template signature followed by the arguments
1135 freplace-objc-classes
1136 ObjC ObjC++ LTO Var(flag_replace_objc_classes)
1137 Used in Fix-and-Continue mode to indicate that object files may be swapped in at runtime
1141 Enable automatic template instantiation
1144 C++ ObjC++ Optimization Var(flag_rtti) Init(1)
1145 Generate run time type descriptor information
1148 C ObjC C++ ObjC++ LTO Optimization Var(flag_short_double)
1149 Use the same size for double as for float
1152 C ObjC C++ ObjC++ Optimization Var(flag_short_enums)
1153 Use the narrowest integer type possible for enumeration types
1156 C ObjC C++ ObjC++ Optimization Var(flag_short_wchar)
1157 Force the underlying type for \"wchar_t\" to be \"unsigned short\"
1160 C ObjC C++ ObjC++ Var(flag_signed_bitfields) Init(1)
1161 When \"signed\" or \"unsigned\" is not given make the bitfield signed
1164 C ObjC C++ ObjC++ LTO Var(flag_signed_char)
1165 Make \"char\" signed by default
1168 C++ ObjC++ Ignore Warn(switch %qs is no longer supported)
1171 C++ ObjC++ Var(flag_detailed_statistics)
1172 Display statistics accumulated during compilation
1175 C++ ObjC++ Optimization Var(flag_strict_enums)
1176 Assume that values of enumeration type are always within the minimum range of that type
1179 C++ ObjC++ Ignore Warn(switch %qs is no longer supported)
1182 C ObjC C++ ObjC++ Joined RejectNegative UInteger
1183 -ftabstop=<number> Distance between tab stops for column reporting
1185 ftemplate-backtrace-limit=
1186 C++ ObjC++ Joined RejectNegative UInteger Var(template_backtrace_limit) Init(10)
1187 Set the maximum number of template instantiation notes for a single warning or error
1190 C++ ObjC++ Joined RejectNegative Undocumented Alias(ftemplate-depth=)
1193 C++ ObjC++ Joined RejectNegative UInteger
1194 -ftemplate-depth=<number> Specify maximum template instantiation depth
1197 C++ ObjC++ Ignore Warn(switch %qs is no longer supported)
1200 C++ ObjC++ Optimization Var(flag_threadsafe_statics) Init(1)
1201 -fno-threadsafe-statics Do not generate thread-safe code for initializing local statics
1204 C ObjC C++ ObjC++ Var(flag_signed_bitfields, 0)
1205 When \"signed\" or \"unsigned\" is not given make the bitfield unsigned
1208 C ObjC C++ ObjC++ LTO Var(flag_signed_char, 0)
1209 Make \"char\" unsigned by default
1212 C++ ObjC++ Var(flag_use_cxa_atexit) Init(DEFAULT_USE_CXA_ATEXIT)
1213 Use __cxa_atexit to register destructors
1215 fuse-cxa-get-exception-ptr
1216 C++ ObjC++ Var(flag_use_cxa_get_exception_ptr) Init(2)
1217 Use __cxa_get_exception_ptr in exception handling
1219 fvisibility-inlines-hidden
1221 Marks all inlined functions and methods as having hidden visibility
1223 fvisibility-ms-compat
1224 C++ ObjC++ Var(flag_visibility_ms_compat)
1225 Changes visibility to match Microsoft Visual Studio by default
1228 C++ ObjC++ Ignore Warn(switch %qs is no longer supported)
1232 C++ ObjC++ Ignore Warn(switch %qs is no longer supported)
1236 C++ ObjC++ Var(flag_weak) Init(1)
1237 Emit common-like symbols as weak symbols
1240 C ObjC C++ ObjC++ Joined RejectNegative
1241 -fwide-exec-charset=<cset> Convert all wide strings and character constants to character set <cset>
1244 C ObjC C++ ObjC++ Var(flag_working_directory) Init(-1)
1245 Generate a #line directive pointing at the current working directory
1248 C++ ObjC++ Ignore Warn(switch %qs is no longer supported)
1252 ObjC ObjC++ Var(flag_zero_link)
1253 Generate lazy class lookup (via objc_getClass()) for use in Zero-Link mode
1256 ObjC ObjC++ Var(flag_gen_declaration)
1257 Dump declarations to a .decl file
1259 femit-struct-debug-baseonly
1261 -femit-struct-debug-baseonly Aggressive reduced debug info for structs
1263 femit-struct-debug-reduced
1265 -femit-struct-debug-reduced Conservative reduced debug info for structs
1267 femit-struct-debug-detailed=
1268 C ObjC C++ ObjC++ Joined
1269 -femit-struct-debug-detailed=<spec-list> Detailed reduced debug info for structs
1271 fext-numeric-literals
1273 Interpret imaginary, fixed-point, or other gnu number suffix as the corresponding
1274 number literal rather than a user-defined number literal.
1277 C ObjC C++ ObjC++ Joined Separate MissingArgError(missing path after %qs)
1278 -idirafter <dir> Add <dir> to the end of the system include path
1281 C ObjC C++ ObjC++ Joined Separate MissingArgError(missing filename after %qs)
1282 -imacros <file> Accept definition of macros in <file>
1285 C ObjC C++ ObjC++ Joined Separate
1286 -imultilib <dir> Set <dir> to be the multilib include subdirectory
1289 C ObjC C++ ObjC++ Joined Separate MissingArgError(missing filename after %qs)
1290 -include <file> Include the contents of <file> before other files
1293 C ObjC C++ ObjC++ Joined Separate
1294 -iprefix <path> Specify <path> as a prefix for next two options
1297 C ObjC C++ ObjC++ Joined Separate MissingArgError(missing path after %qs)
1298 -isysroot <dir> Set <dir> to be the system root directory
1301 C ObjC C++ ObjC++ Joined Separate MissingArgError(missing path after %qs)
1302 -isystem <dir> Add <dir> to the start of the system include path
1305 C ObjC C++ ObjC++ Joined Separate MissingArgError(missing path after %qs)
1306 -iquote <dir> Add <dir> to the end of the quote include path
1309 C ObjC C++ ObjC++ Joined Separate
1310 -iwithprefix <dir> Add <dir> to the end of the system include path
1313 C ObjC C++ ObjC++ Joined Separate
1314 -iwithprefixbefore <dir> Add <dir> to the end of the main include path
1317 C Undocumented RejectDriver
1324 Do not search standard system include directories (those specified with -isystem will still be used)
1328 Do not search standard system include directories for C++
1331 C ObjC C++ ObjC++ Joined Separate
1332 ; Documented in common.opt
1335 C ObjC C++ ObjC++ Alias(Wpedantic)
1336 ; Documented in common.opt
1338 print-objc-runtime-info
1340 Generate C header of platform-specific features
1344 Remap file names when including files
1348 Conform to the ISO 1998 C++ standard revised by the 2003 technical corrigendum
1351 C++ ObjC++ Alias(std=c++98)
1352 Conform to the ISO 1998 C++ standard revised by the 2003 technical corrigendum
1356 Conform to the ISO 2011 C++ standard
1359 C++ ObjC++ Alias(std=c++11) Undocumented
1360 Deprecated in favor of -std=c++11
1364 Conform to the ISO 2014(?) C++ draft standard (experimental and incomplete support)
1367 C++ ObjC++ Alias(std=c++1y) Undocumented
1371 Conform to the ISO 2011 C standard (experimental and incomplete support)
1374 C ObjC Alias(std=c11)
1375 Deprecated in favor of -std=c11
1378 C ObjC Alias(std=c90)
1379 Conform to the ISO 1990 C standard
1383 Conform to the ISO 1990 C standard
1387 Conform to the ISO 1999 C standard
1390 C ObjC Alias(std=c99)
1391 Deprecated in favor of -std=c99
1395 Conform to the ISO 1998 C++ standard revised by the 2003 technical
1396 corrigendum with GNU extensions
1399 C++ ObjC++ Alias(std=gnu++98)
1400 Conform to the ISO 1998 C++ standard revised by the 2003 technical
1401 corrigendum with GNU extensions
1405 Conform to the ISO 2011 C++ standard with GNU extensions (experimental and incomplete support)
1408 C++ ObjC++ Alias(std=gnu++11)
1409 Deprecated in favor of -std=gnu++11
1413 Conform to the ISO 201y(7?) C++ draft standard with GNU extensions (experimental and incomplete support)
1416 C++ ObjC++ Alias(std=gnu++1y) Undocumented
1420 Conform to the ISO 2011 C standard with GNU extensions (experimental and incomplete support)
1423 C ObjC Alias(std=gnu11)
1424 Deprecated in favor of -std=gnu11
1427 C ObjC Alias(std=gnu90)
1428 Conform to the ISO 1990 C standard with GNU extensions
1432 Conform to the ISO 1990 C standard with GNU extensions
1436 Conform to the ISO 1999 C standard with GNU extensions
1439 C ObjC Alias(std=gnu99)
1440 Deprecated in favor of -std=gnu99
1443 C ObjC Alias(std=c90)
1444 Conform to the ISO 1990 C standard
1448 Conform to the ISO 1990 C standard as amended in 1994
1451 C ObjC Alias(std=c99)
1452 Conform to the ISO 1999 C standard
1455 C ObjC Alias(std=c99)
1456 Deprecated in favor of -std=iso9899:1999
1459 C ObjC Alias(std=c11)
1460 Conform to the ISO 2011 C standard (experimental and incomplete support)
1467 Enable traditional preprocessing
1471 -trigraphs Support ISO C trigraphs
1474 C ObjC C++ ObjC++ Var(flag_undef)
1475 Do not predefine system-specific and GCC-specific macros
1479 ; Documented in common.opt
1483 ; Documented in common.opt
1485 ; This comment is to ensure we retain the blank line above.