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 C++ ObjC++ Var(warn_logical_op) Init(0) Warning
289 Warn when a logical operator is suspiciously always evaluating to true or false
292 C ObjC C++ ObjC++ Var(warn_long_long) Init(-1) Warning
293 Do not warn about using \"long long\" when -pedantic
296 C ObjC C++ ObjC++ Var(warn_main) Init(-1) Warning
297 Warn about suspicious declarations of \"main\"
300 C ObjC C++ ObjC++ Var(warn_missing_braces) Warning
301 Warn about possibly missing braces around initializers
303 Wmissing-declarations
304 C ObjC C++ ObjC++ Var(warn_missing_declarations) Warning
305 Warn about global functions without previous declarations
307 Wmissing-field-initializers
308 C ObjC C++ ObjC++ Var(warn_missing_field_initializers) Init(-1) Warning
309 Warn about missing fields in struct initializers
311 Wmissing-format-attribute
312 C ObjC C++ ObjC++ Var(warn_missing_format_attribute) Warning
313 Warn about functions which might be candidates for format attributes
315 Wmissing-include-dirs
316 C ObjC C++ ObjC++ Warning
317 Warn about user-specified include directories that do not exist
319 Wmissing-parameter-type
320 C ObjC Var(warn_missing_parameter_type) Init(-1) Warning
321 Warn about function parameters declared without a type specifier in K&R-style functions
324 C ObjC Var(warn_missing_prototypes) Warning
325 Warn about global functions without prototypes
328 C ObjC C++ ObjC++ Warning
329 Warn about use of multi-character character constants
332 C ObjC Var(warn_nested_externs) Warning
333 Warn about \"extern\" declarations not at file scope
336 C++ ObjC++ Var(warn_nontemplate_friend) Init(1) Warning
337 Warn when non-templatized friend functions are declared within a template
340 C++ ObjC++ Var(warn_nonvdtor) Warning
341 Warn about non-virtual destructors
344 C ObjC Var(warn_nonnull) Warning
345 Warn about NULL being passed to argument slots marked as requiring non-NULL
348 C ObjC C++ ObjC++ Joined Warning
349 -Wnormalized=<id|nfc|nfkc> Warn about non-normalised Unicode strings
352 C++ ObjC++ Var(warn_old_style_cast) Warning
353 Warn if a C-style cast is used in a program
355 Wold-style-declaration
356 C ObjC Var(warn_old_style_declaration) Init(-1) Warning
357 Warn for obsolescent usage in a declaration
359 Wold-style-definition
360 C ObjC Var(warn_old_style_definition) Warning
361 Warn if an old-style parameter definition is used
364 C ObjC C++ ObjC++ Var(warn_overlength_strings) Init(-1) Warning
365 Warn if a string is longer than the maximum portable length specified by the standard
368 C++ ObjC++ Var(warn_overloaded_virtual) Warning
369 Warn about overloaded virtual function names
372 C ObjC Var(warn_override_init) Init(-1) Warning
373 Warn about overriding initializers without side effects
375 Wpacked-bitfield-compat
376 C ObjC C++ ObjC++ Var(warn_packed_bitfield_compat) Init(-1) Warning
377 Warn about packed bit-fields whose offset changed in GCC 4.4
380 C ObjC C++ ObjC++ Var(warn_parentheses) Warning
381 Warn about possibly missing parentheses
384 C++ ObjC++ Var(warn_pmf2ptr) Init(1) Warning
385 Warn when converting the type of pointers to member functions
388 C ObjC C++ ObjC++ Var(warn_pointer_arith) Warning
389 Warn about function pointer arithmetic
392 C ObjC Var(warn_pointer_to_int_cast) Init(1) Warning
393 Warn when a pointer is cast to an integer of a different size
396 C ObjC C++ ObjC++ Var(warn_pragmas) Init(1) Warning
397 Warn about misuses of pragmas
400 ObjC ObjC++ Var(warn_protocol) Init(1) Warning
401 Warn if inherited methods are unimplemented
404 C ObjC C++ ObjC++ Var(warn_redundant_decls) Warning
405 Warn about multiple declarations of the same object
408 C++ ObjC++ Var(warn_reorder) Warning
409 Warn when the compiler reorders code
412 C ObjC C++ ObjC++ Var(warn_return_type) Warning
413 Warn whenever a function's return type defaults to \"int\" (C), or about inconsistent return types (C++)
416 ObjC ObjC++ Var(warn_selector) Warning
417 Warn if a selector has multiple methods
420 C ObjC C++ ObjC++ Var(warn_sequence_point) Warning
421 Warn about possible violations of sequence point rules
424 C ObjC C++ ObjC++ Var(warn_sign_compare) Init(-1) Warning
425 Warn about signed-unsigned comparisons
428 C++ ObjC++ Var(warn_sign_promo) Warning
429 Warn when overload promotes from unsigned to signed
431 Wstrict-null-sentinel
433 Warn about uncasted NULL used as sentinel
436 C ObjC Var(warn_strict_prototypes) Warning
437 Warn about unprototyped function declarations
439 Wstrict-selector-match
440 ObjC ObjC++ Var(warn_strict_selector_match) Warning
441 Warn if type signatures of candidate methods do not match exactly
444 C C++ Var(warn_sync_nand) Init(1) Warning
445 Warn when __sync_fetch_and_nand and __sync_nand_and_fetch built-in functions are used
448 C++ ObjC++ Var(warn_synth) Warning
449 Deprecated. This switch has no effect
452 C ObjC C++ ObjC++ Warning
453 ; Documented in common.opt
456 C ObjC Var(warn_traditional) Warning
457 Warn about features not present in traditional C
459 Wtraditional-conversion
460 C ObjC Var(warn_traditional_conversion) Warning
461 Warn of prototypes causing type conversions different from what would happen in the absence of prototype
464 C ObjC C++ ObjC++ Warning
465 Warn if trigraphs are encountered that might affect the meaning of the program
468 ObjC ObjC++ Var(warn_undeclared_selector) Warning
469 Warn about @selector()s without previously declared methods
472 C ObjC C++ ObjC++ Warning
473 Warn if an undefined macro is used in an #if directive
476 C ObjC C++ ObjC++ Warning
477 Warn about unrecognized pragmas
479 Wunsuffixed-float-constants
480 C ObjC Var(warn_unsuffixed_float_constants) Warning
481 Warn about unsuffixed float constants
484 C ObjC C++ ObjC++ Warning
485 Warn about macros defined in the main file that are not used
488 C ObjC C++ ObjC++ Warning
489 Do not warn about using variadic macros when -pedantic
492 C ObjC C++ ObjC++ Var(warn_vla) Init(-1) Warning
493 Warn if a variable length array is used
495 Wvolatile-register-var
496 C ObjC C++ ObjC++ Var(warn_volatile_register_var) Warning
497 Warn when a register variable is declared volatile
500 C ObjC C++ ObjC++ Var(warn_write_strings) Warning
501 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.
504 C ObjC Var(warn_pointer_sign) Init(-1) Warning
505 Warn when a pointer differs in signedness in an assignment
509 A synonym for -std=c89 (for C) or -std=c++98 (for C++)
512 C ObjC C++ ObjC++ Joined
513 ; Documented in common.opt. FIXME - what about -dI, -dD, -dN and -dD?
517 Enforce class member access control semantics
522 falt-external-templates
524 Change when template instances are emitted
528 Recognize the \"asm\" keyword
532 Recognize built-in functions
535 C ObjC C++ ObjC++ Joined
539 Check the return value of new
543 Allow the arguments of the '?' operator to have different types
547 Reduce the size of object files
549 fconstant-string-class=
551 -fconst-string-class=<name> Use class <name> for constant strings
555 Inline member functions by default
559 Preprocess directives only.
561 fdollars-in-identifiers
563 Permit '$' as an identifier character
570 Generate code to check exception specifications
576 C ObjC C++ ObjC++ Joined RejectNegative
577 -fexec-charset=<cset> Convert all strings and character constants to character set <cset>
579 fextended-identifiers
581 Permit universal character names (\\u and \\U) in identifiers
584 C ObjC C++ ObjC++ Joined RejectNegative
585 -finput-charset=<cset> Specify the default character set for source files
593 Scope of for-init-statement variables is local to the loop
597 Do not assume that standard C libraries and \"main\" exist
601 Recognize GNU-defined keywords
605 Generate code for GNU runtime environment
608 C ObjC Var(flag_gnu89_inline) Init(-1)
609 Use traditional GNU semantics for inline functions
615 C++ ObjC++ Optimization
622 Assume normal C execution environment
626 Enable support for huge objects
630 Export functions even if they can be inlined
632 fimplicit-inline-templates
634 Emit implicit instantiations of inline templates
638 Emit implicit instantiations of templates
641 C++ ObjC++ Var(flag_friend_injection)
642 Inject friend functions into enclosing namespace
647 flax-vector-conversions
649 Allow implicit conversions between vectors with differing numbers of subparts and/or differing element types.
653 Don't warn about uses of Microsoft extensions
655 fname-mangling-version-
663 Generate code for NeXT (Apple Mac OS X) runtime environment
667 Assume that receivers of Objective-C messages may be nil
675 ; Generate special '- .cxx_construct' and '- .cxx_destruct' methods
676 ; to initialize any non-POD ivars in Objective-C++ classes.
677 fobjc-call-cxx-cdtors
678 ObjC++ Var(flag_objc_call_cxx_cdtors)
679 Generate special Objective-C methods to initialize/destroy non-POD C++ ivars, if needed
681 fobjc-direct-dispatch
682 ObjC ObjC++ Var(flag_objc_direct_dispatch)
683 Allow fast jumps to the message dispatcher
685 ; Nonzero means that we will allow new ObjC exception syntax (@throw,
686 ; @try, etc.) in source code.
688 ObjC ObjC++ Var(flag_objc_exceptions)
689 Enable Objective-C exception and synchronization syntax
692 ObjC ObjC++ Var(flag_objc_gc)
693 Enable garbage collection (GC) in Objective-C/Objective-C++ programs
695 ; Nonzero means that we generate NeXT setjmp based exceptions.
696 fobjc-sjlj-exceptions
697 ObjC ObjC++ Var(flag_objc_sjlj_exceptions) Init(-1)
698 Enable Objective-C setjmp exception handling runtime
701 C ObjC C++ ObjC++ Var(flag_openmp)
702 Enable OpenMP (implies -frecursive in Fortran)
706 Recognize C++ keywords like \"compl\" and \"xor\"
710 Enable optional diagnostics
717 Look for and use PCH files even when preprocessing
721 Downgrade conformance errors to warnings
725 Treat the input file as already preprocessed
729 -fno-pretty-templates Do not pretty-print template specializations as the template signature followed by the arguments
731 freplace-objc-classes
733 Used in Fix-and-Continue mode to indicate that object files may be swapped in at runtime
737 Enable automatic template instantiation
740 C++ ObjC++ Optimization
741 Generate run time type descriptor information
744 C ObjC C++ ObjC++ Optimization
745 Use the same size for double as for float
748 C ObjC C++ ObjC++ Optimization
749 Use the narrowest integer type possible for enumeration types
752 C ObjC C++ ObjC++ Optimization
753 Force the underlying type for \"wchar_t\" to be \"unsigned short\"
757 When \"signed\" or \"unsigned\" is not given make the bitfield signed
761 Make \"char\" signed by default
768 Display statistics accumulated during compilation
774 C ObjC C++ ObjC++ Joined RejectNegative UInteger
775 -ftabstop=<number> Distance between tab stops for column reporting
778 C++ ObjC++ Joined RejectNegative UInteger
779 -ftemplate-depth-<number> Specify maximum template instantiation depth
785 C++ ObjC++ Optimization
786 -fno-threadsafe-statics Do not generate thread-safe code for initializing local statics
790 When \"signed\" or \"unsigned\" is not given make the bitfield unsigned
794 Make \"char\" unsigned by default
798 Use __cxa_atexit to register destructors
800 fuse-cxa-get-exception-ptr
802 Use __cxa_get_exception_ptr in exception handling
804 fvisibility-inlines-hidden
806 Marks all inlined methods as having hidden visibility
808 fvisibility-ms-compat
809 C++ ObjC++ Var(flag_visibility_ms_compat)
810 Changes visibility to match Microsoft Visual Studio by default
814 Discard unused virtual functions
818 Implement vtables using thunks
822 Emit common-like symbols as weak symbols
825 C ObjC C++ ObjC++ Joined RejectNegative
826 -fwide-exec-charset=<cset> Convert all wide strings and character constants to character set <cset>
830 Generate a #line directive pointing at the current working directory
834 Emit cross referencing information
838 Generate lazy class lookup (via objc_getClass()) for use in Zero-Link mode
842 Dump declarations to a .decl file
844 femit-struct-debug-baseonly
846 -femit-struct-debug-baseonly Aggressive reduced debug info for structs
848 femit-struct-debug-reduced
850 -femit-struct-debug-reduced Conservative reduced debug info for structs
852 femit-struct-debug-detailed=
853 C ObjC C++ ObjC++ Joined
854 -femit-struct-debug-detailed=<spec-list> Detailed reduced debug info for structs
857 C ObjC C++ ObjC++ Joined Separate
858 -idirafter <dir> Add <dir> to the end of the system include path
861 C ObjC C++ ObjC++ Joined Separate
862 -imacros <file> Accept definition of macros in <file>
865 C ObjC C++ ObjC++ Joined Separate
866 -imultilib <dir> Set <dir> to be the multilib include subdirectory
869 C ObjC C++ ObjC++ Joined Separate
870 -include <file> Include the contents of <file> before other files
873 C ObjC C++ ObjC++ Joined Separate
874 -iprefix <path> Specify <path> as a prefix for next two options
877 C ObjC C++ ObjC++ Joined Separate
878 -isysroot <dir> Set <dir> to be the system root directory
881 C ObjC C++ ObjC++ Joined Separate
882 -isystem <dir> Add <dir> to the start of the system include path
885 C ObjC C++ ObjC++ Joined Separate
886 -iquote <dir> Add <dir> to the end of the quote include path
889 C ObjC C++ ObjC++ Joined Separate
890 -iwithprefix <dir> Add <dir> to the end of the system include path
893 C ObjC C++ ObjC++ Joined Separate
894 -iwithprefixbefore <dir> Add <dir> to the end of the main include path
900 C ObjC C++ ObjC++ Undocumented
904 Do not search standard system include directories (those specified with -isystem will still be used)
908 Do not search standard system include directories for C++
911 C ObjC C++ ObjC++ Joined Separate
912 ; Documented in common.opt
916 ; Documented in common.opt
920 ; Documented in common.opt
922 print-objc-runtime-info
924 Generate C header of platform-specific features
928 Print a checksum of the executable for PCH validity checking, and stop
932 Remap file names when including files
936 Conform to the ISO 1998 C++ standard
940 Conform to the ISO 1998 C++ standard, with extensions that are likely to
941 become a part of the upcoming ISO C++ standard, dubbed C++0x. Note that the
942 extensions enabled by this mode are experimental and may be removed in
943 future releases of GCC.
947 Conform to the ISO 1990 C standard
951 Conform to the ISO 1999 C standard
955 Deprecated in favor of -std=c99
959 Conform to the ISO 1998 C++ standard with GNU extensions
963 Conform to the ISO 1998 C++ standard, with GNU extensions and
964 extensions that are likely to become a part of the upcoming ISO C++
965 standard, dubbed C++0x. Note that the extensions enabled by this mode
966 are experimental and may be removed in future releases of GCC.
970 Conform to the ISO 1990 C standard with GNU extensions
974 Conform to the ISO 1999 C standard with GNU extensions
978 Deprecated in favor of -std=gnu99
982 Conform to the ISO 1990 C standard
986 Conform to the ISO 1990 C standard as amended in 1994
990 Conform to the ISO 1999 C standard
994 Deprecated in favor of -std=iso9899:1999
998 Enable traditional preprocessing
1002 -trigraphs Support ISO C trigraphs
1006 Do not predefine system-specific and GCC-specific macros
1009 Common C ObjC C++ ObjC++
1010 Enable verbose output
1014 ; Documented in common.opt
1016 ; This comment is to ensure we retain the blank line above.