1 ; Options for the C, ObjC, C++ and ObjC++ front ends.
2 ; Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009
3 ; 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 for a description of this file's format.
23 ; Please try to keep this file in ASCII collating order.
38 C ObjC C++ ObjC++ Joined Separate
41 C ObjC C++ ObjC++ Joined Separate
42 -A<question>=<answer> Assert the <answer> to <question>. Putting '-' before <question> disables the <answer> to <question>
46 Do not discard comments
50 Do not discard comments in macro expansions
53 C ObjC C++ ObjC++ Joined Separate
54 -D<macro>[=<val>] Define a <macro> with <val> as its value. If just <macro> is given, <val> is taken to be 1
57 C ObjC C++ ObjC++ Undocumented
60 C ObjC C++ ObjC++ Joined Separate
61 -F <dir> Add <dir> to the end of the main framework include path
65 Print the name of header files as they are used
68 C ObjC C++ ObjC++ Joined Separate
69 -I <dir> Add <dir> to the end of the main include path
73 Generate make dependencies
76 C ObjC C++ ObjC++ Separate
77 Generate make dependencies and compile
80 C ObjC C++ ObjC++ Joined Separate
81 -MF <file> Write dependency output to the given file
85 Treat missing header files as generated files
89 Like -M but ignore system header files
92 C ObjC C++ ObjC++ Separate
93 Like -MD but ignore system header files
97 Generate phony targets for all headers
100 C ObjC C++ ObjC++ Joined Separate
101 -MQ <target> Add a MAKE-quoted target
104 C ObjC C++ ObjC++ Joined Separate
105 -MT <target> Add an unquoted target
109 Do not generate #line directives
112 C ObjC C++ ObjC++ Joined Separate
113 -U<macro> Undefine <macro>
116 C ObjC C++ ObjC++ Var(warn_abi) Warning
117 Warn about things that will change when compiling with an ABI-compliant compiler
120 C ObjC C++ ObjC++ Var(warn_psabi) Init(1) Undocumented
123 C ObjC C++ ObjC++ Var(warn_address) Warning
124 Warn about suspicious uses of memory addresses
127 C ObjC C++ ObjC++ Warning
128 Enable most warning messages
131 ObjC ObjC++ Var(warn_assign_intercept) Warning
132 Warn whenever an Objective-C assignment is being intercepted by the garbage collector
135 C ObjC Var(warn_bad_function_cast) Warning
136 Warn about casting functions to incompatible types
138 Wbuiltin-macro-redefined
139 C ObjC C++ ObjC++ Warning
140 Warn when a built-in preprocessor macro is undefined or redefined
143 C ObjC Var(warn_cxx_compat) Warning
144 Warn about C constructs that are not in the common subset of C and C++
147 C++ ObjC++ Var(warn_cxx0x_compat) Warning
148 Warn about C++ constructs whose meaning differs between ISO C++ 1998 and ISO C++ 200x
151 C ObjC C++ ObjC++ Var(warn_cast_qual) Warning
152 Warn about casts which discard qualifiers
155 C ObjC C++ ObjC++ Var(warn_char_subscripts) Warning
156 Warn about subscripts whose type is \"char\"
159 C ObjC C++ ObjC++ Var(warn_clobbered) Init(-1) Warning
160 Warn about variables that might be changed by \"longjmp\" or \"vfork\"
163 C ObjC C++ ObjC++ Warning
164 Warn about possibly nested block comments, and C++ comments spanning more than one physical line
167 C ObjC C++ ObjC++ Warning
168 Synonym for -Wcomment
171 C ObjC C++ ObjC++ Var(warn_conversion) Warning
172 Warn for implicit type conversions that may change a value
175 C ObjC C++ ObjC++ Var(warn_sign_conversion) Init(-1)
176 Warn for implicit type conversions between signed and unsigned integers
179 C++ ObjC++ Var(warn_ctor_dtor_privacy) Warning
180 Warn when all constructors and destructors are private
182 Wdeclaration-after-statement
183 C ObjC Var(warn_declaration_after_statement) Warning
184 Warn when a declaration is found after a statement
187 C C++ ObjC ObjC++ Var(warn_deprecated) Init(1) Warning
188 Warn if a deprecated compiler feature, class, method, or field is used
191 C ObjC C++ ObjC++ Var(warn_div_by_zero) Init(1) Warning
192 Warn about compile-time integer division by zero
195 C++ ObjC++ Var(warn_ecpp) Warning
196 Warn about violations of Effective C++ style rules
199 C ObjC C++ ObjC++ Var(warn_empty_body) Init(-1) Warning
200 Warn about an empty body in an if or else statement
203 C ObjC C++ ObjC++ Warning
204 Warn about stray tokens after #elif and #endif
207 C ObjC C++ ObjC++ Var(warn_enum_compare) Init(-1) Warning
208 Warn about comparison of different enum types
212 ; Documented in common.opt
214 Werror-implicit-function-declaration
215 C ObjC RejectNegative Warning
216 This switch is deprecated; use -Werror=implicit-function-declaration instead
219 C ObjC C++ ObjC++ Var(warn_float_equal) Warning
220 Warn if testing floating point numbers for equality
223 C ObjC C++ ObjC++ Warning
224 Warn about printf/scanf/strftime/strfmon format string anomalies
227 C ObjC C++ ObjC++ Var(warn_format_extra_args) Warning
228 Warn if passing too many arguments to a function for its format string
231 C ObjC C++ ObjC++ Var(warn_format_nonliteral) Warning
232 Warn about format strings that are not literals
235 C ObjC C++ ObjC++ Var(warn_format_contains_nul) Warning
236 Warn about format strings that contain NUL bytes
239 C ObjC C++ ObjC++ Var(warn_format_security) Warning
240 Warn about possible security problems with format functions
243 C ObjC C++ ObjC++ Var(warn_format_y2k) Warning
244 Warn about strftime formats yielding 2-digit years
247 C ObjC Var(warn_format_zero_length) Warning
248 Warn about zero-length formats
251 C ObjC C++ ObjC++ Joined Warning
254 C C++ Var(warn_ignored_qualifiers) Init(-1) Warning
255 Warn whenever type qualifiers are ignored.
258 C ObjC C++ ObjC++ Var(warn_init_self) Warning
259 Warn about variables which are initialized to themselves
262 C ObjC C++ ObjC++ Warning
264 Wimplicit-function-declaration
265 C ObjC Var(warn_implicit_function_declaration) Init(-1) Warning
266 Warn about implicit function declarations
269 C ObjC Var(warn_implicit_int) Warning
270 Warn when a declaration does not specify a type
273 C ObjC C++ ObjC++ Undocumented
276 C ObjC Var(warn_int_to_pointer_cast) Init(1) Warning
277 Warn when there is a cast to a pointer from an integer of a different size
280 C++ ObjC++ Var(warn_invalid_offsetof) Init(1) Warning
281 Warn about invalid uses of the \"offsetof\" macro
284 C ObjC C++ ObjC++ Warning
285 Warn about PCH files that are found but not used
288 C Objc Var(warn_jump_misses_init) Init(-1) Warning
289 Warn when a jump misses a variable initialization
292 C ObjC C++ ObjC++ Var(warn_logical_op) Init(0) Warning
293 Warn when a logical operator is suspiciously always evaluating to true or false
296 C ObjC C++ ObjC++ Var(warn_long_long) Init(-1) Warning
297 Do not warn about using \"long long\" when -pedantic
300 C ObjC C++ ObjC++ Var(warn_main) Init(-1) Warning
301 Warn about suspicious declarations of \"main\"
304 C ObjC C++ ObjC++ Var(warn_missing_braces) Warning
305 Warn about possibly missing braces around initializers
307 Wmissing-declarations
308 C ObjC C++ ObjC++ Var(warn_missing_declarations) Warning
309 Warn about global functions without previous declarations
311 Wmissing-field-initializers
312 C ObjC C++ ObjC++ Var(warn_missing_field_initializers) Init(-1) Warning
313 Warn about missing fields in struct initializers
315 Wmissing-format-attribute
316 C ObjC C++ ObjC++ Var(warn_missing_format_attribute) Warning
317 Warn about functions which might be candidates for format attributes
319 Wmissing-include-dirs
320 C ObjC C++ ObjC++ Warning
321 Warn about user-specified include directories that do not exist
323 Wmissing-parameter-type
324 C ObjC Var(warn_missing_parameter_type) Init(-1) Warning
325 Warn about function parameters declared without a type specifier in K&R-style functions
328 C ObjC Var(warn_missing_prototypes) Warning
329 Warn about global functions without prototypes
332 C ObjC C++ ObjC++ Warning
333 Warn about use of multi-character character constants
336 C ObjC Var(warn_nested_externs) Warning
337 Warn about \"extern\" declarations not at file scope
340 C++ ObjC++ Var(warn_nontemplate_friend) Init(1) Warning
341 Warn when non-templatized friend functions are declared within a template
344 C++ ObjC++ Var(warn_nonvdtor) Warning
345 Warn about non-virtual destructors
348 C ObjC Var(warn_nonnull) Warning
349 Warn about NULL being passed to argument slots marked as requiring non-NULL
352 C ObjC C++ ObjC++ Joined Warning
353 -Wnormalized=<id|nfc|nfkc> Warn about non-normalised Unicode strings
356 C++ ObjC++ Var(warn_old_style_cast) Warning
357 Warn if a C-style cast is used in a program
359 Wold-style-declaration
360 C ObjC Var(warn_old_style_declaration) Init(-1) Warning
361 Warn for obsolescent usage in a declaration
363 Wold-style-definition
364 C ObjC Var(warn_old_style_definition) Warning
365 Warn if an old-style parameter definition is used
368 C ObjC C++ ObjC++ Var(warn_overlength_strings) Init(-1) Warning
369 Warn if a string is longer than the maximum portable length specified by the standard
372 C++ ObjC++ Var(warn_overloaded_virtual) Warning
373 Warn about overloaded virtual function names
376 C ObjC Var(warn_override_init) Init(-1) Warning
377 Warn about overriding initializers without side effects
379 Wpacked-bitfield-compat
380 C ObjC C++ ObjC++ Var(warn_packed_bitfield_compat) Init(-1) Warning
381 Warn about packed bit-fields whose offset changed in GCC 4.4
384 C ObjC C++ ObjC++ Var(warn_parentheses) Warning
385 Warn about possibly missing parentheses
388 C++ ObjC++ Var(warn_pmf2ptr) Init(1) Warning
389 Warn when converting the type of pointers to member functions
392 C ObjC C++ ObjC++ Var(warn_pointer_arith) Warning
393 Warn about function pointer arithmetic
396 C ObjC Var(warn_pointer_to_int_cast) Init(1) Warning
397 Warn when a pointer is cast to an integer of a different size
400 C ObjC C++ ObjC++ Var(warn_pragmas) Init(1) Warning
401 Warn about misuses of pragmas
404 ObjC ObjC++ Var(warn_protocol) Init(1) Warning
405 Warn if inherited methods are unimplemented
408 C ObjC C++ ObjC++ Var(warn_redundant_decls) Warning
409 Warn about multiple declarations of the same object
412 C++ ObjC++ Var(warn_reorder) Warning
413 Warn when the compiler reorders code
416 C ObjC C++ ObjC++ Var(warn_return_type) Warning
417 Warn whenever a function's return type defaults to \"int\" (C), or about inconsistent return types (C++)
420 ObjC ObjC++ Var(warn_selector) Warning
421 Warn if a selector has multiple methods
424 C ObjC C++ ObjC++ Var(warn_sequence_point) Warning
425 Warn about possible violations of sequence point rules
428 C ObjC C++ ObjC++ Var(warn_sign_compare) Init(-1) Warning
429 Warn about signed-unsigned comparisons
432 C++ ObjC++ Var(warn_sign_promo) Warning
433 Warn when overload promotes from unsigned to signed
435 Wstrict-null-sentinel
437 Warn about uncasted NULL used as sentinel
440 C ObjC Var(warn_strict_prototypes) Warning
441 Warn about unprototyped function declarations
443 Wstrict-selector-match
444 ObjC ObjC++ Var(warn_strict_selector_match) Warning
445 Warn if type signatures of candidate methods do not match exactly
448 C C++ Var(warn_sync_nand) Init(1) Warning
449 Warn when __sync_fetch_and_nand and __sync_nand_and_fetch built-in functions are used
452 C++ ObjC++ Var(warn_synth) Warning
453 Deprecated. This switch has no effect
456 C ObjC C++ ObjC++ Warning
457 ; Documented in common.opt
460 C ObjC Var(warn_traditional) Warning
461 Warn about features not present in traditional C
463 Wtraditional-conversion
464 C ObjC Var(warn_traditional_conversion) Warning
465 Warn of prototypes causing type conversions different from what would happen in the absence of prototype
468 C ObjC C++ ObjC++ Warning
469 Warn if trigraphs are encountered that might affect the meaning of the program
472 ObjC ObjC++ Var(warn_undeclared_selector) Warning
473 Warn about @selector()s without previously declared methods
476 C ObjC C++ ObjC++ Warning
477 Warn if an undefined macro is used in an #if directive
480 C ObjC C++ ObjC++ Warning
481 Warn about unrecognized pragmas
483 Wunsuffixed-float-constants
484 C ObjC Var(warn_unsuffixed_float_constants) Warning
485 Warn about unsuffixed float constants
488 C ObjC C++ ObjC++ Warning
489 Warn about macros defined in the main file that are not used
492 C ObjC C++ ObjC++ Var(warn_unused_result) Init(1) Warning
493 Warn if a caller of a function, marked with attribute warn_unused_result, does not use its return value
496 C ObjC C++ ObjC++ Warning
497 Do not warn about using variadic macros when -pedantic
500 C ObjC C++ ObjC++ Var(warn_vla) Init(-1) Warning
501 Warn if a variable length array is used
503 Wvolatile-register-var
504 C ObjC C++ ObjC++ Var(warn_volatile_register_var) Warning
505 Warn when a register variable is declared volatile
508 C ObjC C++ ObjC++ Var(warn_write_strings) Warning
509 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.
512 C ObjC Var(warn_pointer_sign) Init(-1) Warning
513 Warn when a pointer differs in signedness in an assignment
517 A synonym for -std=c89 (for C) or -std=c++98 (for C++)
520 C ObjC C++ ObjC++ Joined
521 ; Documented in common.opt. FIXME - what about -dI, -dD, -dN and -dD?
525 Enforce class member access control semantics
530 falt-external-templates
532 Change when template instances are emitted
536 Recognize the \"asm\" keyword
540 Recognize built-in functions
543 C ObjC C++ ObjC++ Joined
547 Check the return value of new
551 Allow the arguments of the '?' operator to have different types
555 Reduce the size of object files
557 fconstant-string-class=
559 -fconst-string-class=<name> Use class <name> for constant strings
563 Inline member functions by default
567 Preprocess directives only.
569 fdollars-in-identifiers
571 Permit '$' as an identifier character
578 Generate code to check exception specifications
584 C ObjC C++ ObjC++ Joined RejectNegative
585 -fexec-charset=<cset> Convert all strings and character constants to character set <cset>
587 fextended-identifiers
589 Permit universal character names (\\u and \\U) in identifiers
592 C ObjC C++ ObjC++ Joined RejectNegative
593 -finput-charset=<cset> Specify the default character set for source files
601 Scope of for-init-statement variables is local to the loop
605 Do not assume that standard C libraries and \"main\" exist
609 Recognize GNU-defined keywords
613 Generate code for GNU runtime environment
616 C ObjC Var(flag_gnu89_inline) Init(-1)
617 Use traditional GNU semantics for inline functions
623 C++ ObjC++ Optimization
630 Assume normal C execution environment
634 Enable support for huge objects
638 Export functions even if they can be inlined
640 fimplicit-inline-templates
642 Emit implicit instantiations of inline templates
646 Emit implicit instantiations of templates
649 C++ ObjC++ Var(flag_friend_injection)
650 Inject friend functions into enclosing namespace
655 flax-vector-conversions
657 Allow implicit conversions between vectors with differing numbers of subparts and/or differing element types.
661 Don't warn about uses of Microsoft extensions
663 fname-mangling-version-
671 Generate code for NeXT (Apple Mac OS X) runtime environment
675 Assume that receivers of Objective-C messages may be nil
683 ; Generate special '- .cxx_construct' and '- .cxx_destruct' methods
684 ; to initialize any non-POD ivars in Objective-C++ classes.
685 fobjc-call-cxx-cdtors
686 ObjC++ Var(flag_objc_call_cxx_cdtors)
687 Generate special Objective-C methods to initialize/destroy non-POD C++ ivars, if needed
689 fobjc-direct-dispatch
690 ObjC ObjC++ Var(flag_objc_direct_dispatch)
691 Allow fast jumps to the message dispatcher
693 ; Nonzero means that we will allow new ObjC exception syntax (@throw,
694 ; @try, etc.) in source code.
696 ObjC ObjC++ Var(flag_objc_exceptions)
697 Enable Objective-C exception and synchronization syntax
700 ObjC ObjC++ Var(flag_objc_gc)
701 Enable garbage collection (GC) in Objective-C/Objective-C++ programs
703 ; Nonzero means that we generate NeXT setjmp based exceptions.
704 fobjc-sjlj-exceptions
705 ObjC ObjC++ Var(flag_objc_sjlj_exceptions) Init(-1)
706 Enable Objective-C setjmp exception handling runtime
709 C ObjC C++ ObjC++ Var(flag_openmp)
710 Enable OpenMP (implies -frecursive in Fortran)
714 Recognize C++ keywords like \"compl\" and \"xor\"
718 Enable optional diagnostics
725 Look for and use PCH files even when preprocessing
729 Downgrade conformance errors to warnings
733 Treat the input file as already preprocessed
737 -fno-pretty-templates Do not pretty-print template specializations as the template signature followed by the arguments
739 freplace-objc-classes
741 Used in Fix-and-Continue mode to indicate that object files may be swapped in at runtime
745 Enable automatic template instantiation
748 C++ ObjC++ Optimization
749 Generate run time type descriptor information
752 C ObjC C++ ObjC++ Optimization
753 Use the same size for double as for float
756 C ObjC C++ ObjC++ Optimization
757 Use the narrowest integer type possible for enumeration types
760 C ObjC C++ ObjC++ Optimization
761 Force the underlying type for \"wchar_t\" to be \"unsigned short\"
765 When \"signed\" or \"unsigned\" is not given make the bitfield signed
769 Make \"char\" signed by default
776 Display statistics accumulated during compilation
782 C ObjC C++ ObjC++ Joined RejectNegative UInteger
783 -ftabstop=<number> Distance between tab stops for column reporting
786 C++ ObjC++ Joined RejectNegative UInteger
787 -ftemplate-depth-<number> Specify maximum template instantiation depth
793 C++ ObjC++ Optimization
794 -fno-threadsafe-statics Do not generate thread-safe code for initializing local statics
798 When \"signed\" or \"unsigned\" is not given make the bitfield unsigned
802 Make \"char\" unsigned by default
806 Use __cxa_atexit to register destructors
808 fuse-cxa-get-exception-ptr
810 Use __cxa_get_exception_ptr in exception handling
812 fvisibility-inlines-hidden
814 Marks all inlined methods as having hidden visibility
816 fvisibility-ms-compat
817 C++ ObjC++ Var(flag_visibility_ms_compat)
818 Changes visibility to match Microsoft Visual Studio by default
822 Discard unused virtual functions
826 Implement vtables using thunks
830 Emit common-like symbols as weak symbols
833 C ObjC C++ ObjC++ Joined RejectNegative
834 -fwide-exec-charset=<cset> Convert all wide strings and character constants to character set <cset>
838 Generate a #line directive pointing at the current working directory
842 Emit cross referencing information
846 Generate lazy class lookup (via objc_getClass()) for use in Zero-Link mode
850 Dump declarations to a .decl file
852 femit-struct-debug-baseonly
854 -femit-struct-debug-baseonly Aggressive reduced debug info for structs
856 femit-struct-debug-reduced
858 -femit-struct-debug-reduced Conservative reduced debug info for structs
860 femit-struct-debug-detailed=
861 C ObjC C++ ObjC++ Joined
862 -femit-struct-debug-detailed=<spec-list> Detailed reduced debug info for structs
865 C ObjC C++ ObjC++ Joined Separate
866 -idirafter <dir> Add <dir> to the end of the system include path
869 C ObjC C++ ObjC++ Joined Separate
870 -imacros <file> Accept definition of macros in <file>
873 C ObjC C++ ObjC++ Joined Separate
874 -imultilib <dir> Set <dir> to be the multilib include subdirectory
877 C ObjC C++ ObjC++ Joined Separate
878 -include <file> Include the contents of <file> before other files
881 C ObjC C++ ObjC++ Joined Separate
882 -iprefix <path> Specify <path> as a prefix for next two options
885 C ObjC C++ ObjC++ Joined Separate
886 -isysroot <dir> Set <dir> to be the system root directory
889 C ObjC C++ ObjC++ Joined Separate
890 -isystem <dir> Add <dir> to the start of the system include path
893 C ObjC C++ ObjC++ Joined Separate
894 -iquote <dir> Add <dir> to the end of the quote include path
897 C ObjC C++ ObjC++ Joined Separate
898 -iwithprefix <dir> Add <dir> to the end of the system include path
901 C ObjC C++ ObjC++ Joined Separate
902 -iwithprefixbefore <dir> Add <dir> to the end of the main include path
908 C ObjC C++ ObjC++ Undocumented
912 Do not search standard system include directories (those specified with -isystem will still be used)
916 Do not search standard system include directories for C++
919 C ObjC C++ ObjC++ Joined Separate
920 ; Documented in common.opt
924 ; Documented in common.opt
928 ; Documented in common.opt
930 print-objc-runtime-info
932 Generate C header of platform-specific features
936 Print a checksum of the executable for PCH validity checking, and stop
940 Remap file names when including files
944 Conform to the ISO 1998 C++ standard
948 Conform to the ISO 1998 C++ standard, with extensions that are likely to
949 become a part of the upcoming ISO C++ standard, dubbed C++0x. Note that the
950 extensions enabled by this mode are experimental and may be removed in
951 future releases of GCC.
955 Conform to the ISO 1990 C standard
959 Conform to the ISO 1999 C standard
963 Deprecated in favor of -std=c99
967 Conform to the ISO 1998 C++ standard with GNU extensions
971 Conform to the ISO 1998 C++ standard, with GNU extensions and
972 extensions that are likely to become a part of the upcoming ISO C++
973 standard, dubbed C++0x. Note that the extensions enabled by this mode
974 are experimental and may be removed in future releases of GCC.
978 Conform to the ISO 1990 C standard with GNU extensions
982 Conform to the ISO 1999 C standard with GNU extensions
986 Deprecated in favor of -std=gnu99
990 Conform to the ISO 1990 C standard
994 Conform to the ISO 1990 C standard as amended in 1994
998 Conform to the ISO 1999 C standard
1002 Deprecated in favor of -std=iso9899:1999
1006 Enable traditional preprocessing
1010 -trigraphs Support ISO C trigraphs
1014 Do not predefine system-specific and GCC-specific macros
1017 Common C ObjC C++ ObjC++
1018 Enable verbose output
1022 ; Documented in common.opt
1024 ; This comment is to ensure we retain the blank line above.