###Driver
-CLASSPATHJava Separate Alias(fclasspath=)
-all-warningsAda AdaWhy AdaSCIL Alias(Wall)
-all-warningsC ObjC C++ ObjC++ Warning Alias(Wall)
-all-warningsFortran Alias(Wall)
-all-warningsJava Alias(Wall)
-ansiC ObjC C++ ObjC++ Alias(ansi)
-assembleDriver Alias(S)
-assertC ObjC C++ ObjC++ Separate Alias(A) MissingArgError(assertion missing after %qs)
-assertFortran Separate Alias(A)
-assert=C ObjC C++ ObjC++ Joined Alias(A) MissingArgError(assertion missing after %qs)
-assert=Fortran Joined Alias(A)
-bootclasspathJava Separate Alias(fbootclasspath=)
-classpathJava Separate Alias(fclasspath=)
-commentsC ObjC C++ ObjC++ Alias(C)
-commentsFortran Alias(C)
-comments-in-macrosC ObjC C++ ObjC++ Alias(CC)
-comments-in-macrosFortran Alias(CC)
-compileDriver Alias(c)
-coverageDriver Alias(coverage)
-debugCommon Alias(g)
-define-macroC ObjC C++ ObjC++ Separate Alias(D) MissingArgError(macro name missing after %qs)
-define-macroFortran Separate Alias(D)
-define-macro=C ObjC C++ ObjC++ Joined Alias(D) MissingArgError(macro name missing after %qs)
-define-macro=Fortran Joined Alias(D)
-dependenciesC ObjC C++ ObjC++ Alias(M)
-dependenciesFortran Alias(M)
-dependenciesJava Alias(M)
-dumpC ObjC C++ ObjC++ Separate Alias(d)
-dumpCommon Separate Alias(d)
-dumpFortran Separate Alias(d)
-dump=C ObjC C++ ObjC++ Joined Alias(d)
-dump=Common Joined Alias(d)
-dump=Fortran Joined Alias(d)
-dumpbaseCommon Separate Alias(dumpbase)
-dumpdirCommon Separate Alias(dumpdir)
-encodingJava Separate Alias(fencoding=)
-entryDriver Separate Alias(e)
-entry=Driver Joined Alias(e)
-extdirsJava Separate Alias(fextdirs=)
-extra-warningsCommon Warning Alias(Wextra)
-for-assemblerDriver Separate Alias(Xassembler)
-for-assembler=Driver JoinedOrMissing Alias(Xassembler)
-for-linkerDriver Separate Alias(Xlinker)
-for-linker=Driver JoinedOrMissing Alias(Xlinker)
-force-linkDriver Separate Alias(u)
-force-link=Driver Joined Alias(u)
-helpCommon Driver Var(help_flag)Display this information
-help=Common Driver Report Joined--help=<class>	Display descriptions of a specific class of options.  <class> is one or more of optimizers, target, warnings, undocumented, params
-imacrosC ObjC C++ ObjC++ Separate Alias(imacros) MissingArgError(missing filename after %qs)
-imacros=C ObjC C++ ObjC++ Joined Alias(imacros) MissingArgError(missing filename after %qs)
-includeC ObjC C++ ObjC++ Separate Alias(include) MissingArgError(missing filename after %qs)
-include-barrierAda AdaWhy AdaSCIL Alias(I, -)
-include-barrierC ObjC C++ ObjC++ Alias(I, -)
-include-barrierFortran Alias(I, -)
-include-directoryAda AdaWhy AdaSCIL Separate Alias(I)
-include-directoryC ObjC C++ ObjC++ Separate Alias(I) MissingArgError(missing path after %qs)
-include-directoryFortran Separate Alias(I)
-include-directoryJava Separate Alias(I)
-include-directory-afterC ObjC C++ ObjC++ Separate Alias(idirafter) MissingArgError(missing path after %qs)
-include-directory-afterFortran Separate Alias(idirafter)
-include-directory-after=C ObjC C++ ObjC++ Joined Alias(idirafter) MissingArgError(missing path after %qs)
-include-directory-after=Fortran Joined Alias(idirafter)
-include-directory=Ada AdaWhy AdaSCIL Joined Alias(I)
-include-directory=C ObjC C++ ObjC++ Joined Alias(I) MissingArgError(missing path after %qs)
-include-directory=Fortran Joined Alias(I)
-include-directory=Java Joined Alias(I)
-include-prefixC ObjC C++ ObjC++ Separate Alias(iprefix)
-include-prefixFortran Separate Alias(iprefix)
-include-prefix=C ObjC C++ ObjC++ JoinedOrMissing Alias(iprefix)
-include-prefix=Fortran JoinedOrMissing Alias(iprefix)
-include-with-prefixC ObjC C++ ObjC++ Separate Alias(iwithprefix)
-include-with-prefix-afterC ObjC C++ ObjC++ Separate Alias(iwithprefix)
-include-with-prefix-after=C ObjC C++ ObjC++ JoinedOrMissing Alias(iwithprefix)
-include-with-prefix-beforeC ObjC C++ ObjC++ Separate Alias(iwithprefixbefore)
-include-with-prefix-before=C ObjC C++ ObjC++ JoinedOrMissing Alias(iwithprefixbefore)
-include-with-prefix=C ObjC C++ ObjC++ JoinedOrMissing Alias(iwithprefix)
-include=C ObjC C++ ObjC++ Joined Alias(include) MissingArgError(missing filename after %qs)
-languageDriver Separate Alias(x)
-language=Driver Joined Alias(x)
-library-directoryDriver Separate Alias(L)
-library-directory=Driver Joined Alias(L)
-no-canonical-prefixesDriver Alias(no-canonical-prefixes)
-no-integrated-cppDriver Alias(no-integrated-cpp)
-no-line-commandsC ObjC C++ ObjC++ Alias(P)
-no-line-commandsFortran Alias(P)
-no-standard-includesAda AdaWhy AdaSCIL Alias(nostdinc)
-no-standard-includesC ObjC C++ ObjC++ Alias(nostdinc)
-no-standard-includesFortran Alias(nostdinc)
-no-standard-librariesAda AdaWhy AdaSCIL Alias(nostdlib)
-no-standard-librariesDriver Alias(nostdlib)
-no-sysroot-suffixDriver Var(no_sysroot_suffix)
-no-warningsC ObjC C++ ObjC++ Alias(w)
-no-warningsCommon Alias(w)
-optimizeCommon Alias(O)
-outputC ObjC C++ ObjC++ Separate Alias(o)
-outputCommon Driver Separate Alias(o) MissingArgError(missing filename after %qs)
-outputFortran Separate Alias(o)
-output-class-directoryJava Separate Alias(foutput-class-dir=)
-output-class-directory=Java Joined Alias(foutput-class-dir=)
-output-pch=C ObjC C++ ObjC++ Joined Separate
-output=C ObjC C++ ObjC++ Joined Alias(o)
-output=Common Driver Joined Alias(o) MissingArgError(missing filename after %qs)
-output=Fortran Joined Alias(o)
-paramCommon Separate--param <param>=<value>	Set parameter <param> to value.  See below for a complete list of parameters
-param=Common Joined Alias(-param)
-pass-exit-codesDriver Alias(pass-exit-codes)
-pedanticC ObjC C++ ObjC++ Alias(pedantic)
-pedanticCommon Alias(Wpedantic)
-pedantic-errorsCommon Alias(pedantic-errors)
-pieDriver Alias(pie)
-pipeDriver Alias(pipe)
-prefixDriver Separate Alias(B)
-prefix=Driver JoinedOrMissing Alias(B)
-preprocessC ObjC C++ ObjC++ Undocumented Alias(E)
-preprocessDriver Alias(E)
-preprocessFortran Undocumented Alias(E)
-print-file-nameDriver Separate Alias(print-file-name=)
-print-file-name=Driver JoinedOrMissing Alias(print-file-name=)
-print-libgcc-file-nameDriver Alias(print-libgcc-file-name)
-print-missing-file-dependenciesC ObjC C++ ObjC++ Alias(MG)
-print-missing-file-dependenciesFortran Alias(MG)
-print-multi-directoryDriver Alias(print-multi-directory)
-print-multi-libDriver Alias(print-multi-lib)
-print-multi-os-directoryDriver Alias(print-multi-os-directory)
-print-multiarchDriver Alias(print-multiarch)
-print-prog-nameDriver Separate Alias(print-prog-name=)
-print-prog-name=Driver JoinedOrMissing Alias(print-prog-name=)
-print-search-dirsDriver Alias(print-search-dirs)
-print-sysrootDriver Alias(print-sysroot)
-print-sysroot-headers-suffixDriver Alias(print-sysroot-headers-suffix)
-profileCommon Alias(p)
-resourceJava Separate Alias(fcompile-resource=)
-resource=Java Joined Alias(fcompile-resource=)
-save-tempsDriver Alias(save-temps)
-sharedDriver Alias(shared)
-specsDriver Separate Alias(specs=)
-specs=Driver Joined Alias(specs=)
-staticDriver Alias(static)
-symbolicDriver Alias(symbolic)
-sysrootDriver Separate Alias(-sysroot=)
-sysroot=Driver JoinedOrMissing
-target-helpCommon DriverAlias for --help=target
-timeDriver Alias(time)
-trace-includesC ObjC C++ ObjC++ Alias(H)
-trace-includesFortran Alias(H)
-traditionalDriver Alias(traditional)
-traditional-cppC ObjC C++ ObjC++ Alias(traditional-cpp)
-trigraphsC ObjC C++ ObjC++ Alias(trigraphs)
-undefine-macroC ObjC C++ ObjC++ Separate Alias(U) MissingArgError(macro name missing after %qs)
-undefine-macroFortran Separate Alias(U)
-undefine-macro=C ObjC C++ ObjC++ Joined Alias(U) MissingArgError(macro name missing after %qs)
-undefine-macro=Fortran Joined Alias(U)
-user-dependenciesC ObjC C++ ObjC++ Alias(MM)
-user-dependenciesFortran Alias(MM)
-user-dependenciesJava Alias(MM)
-verboseCommon C ObjC C++ ObjC++ Alias(v)
-verboseDriver Alias(v)
-verboseFortran Alias(v)
-versionCommon Driver
-write-dependenciesC ObjC C++ ObjC++ NoDriverArg Separate Alias(MD) MissingArgError(missing filename after %qs)
-write-dependenciesFortran NoDriverArg Separate Alias(MD)
-write-user-dependenciesC ObjC C++ ObjC++ NoDriverArg Separate Alias(MMD) MissingArgError(missing filename after %qs)
-write-user-dependenciesFortran NoDriverArg Separate Alias(MMD)
AC ObjC C++ ObjC++ Joined Separate MissingArgError(assertion missing after %qs)-A<question>=<answer>	Assert the <answer> to <question>.  Putting '-' before <question> disables the <answer> to <question>
AFortran Joined Separate
BDriver Joined Separate
CC ObjC C++ ObjC++Do not discard comments
CDriver
CFortran
CCC ObjC C++ ObjC++Do not discard comments in macro expansions
CCFortran
CLASSPATHJava Separate Alias(fclasspath=)
DC ObjC C++ ObjC++ Joined Separate MissingArgError(macro name missing after %qs)-D<macro>[=<val>]	Define a <macro> with <val> as its value.  If just <macro> is given, <val> is taken to be 1
DDriver Joined Separate
DFortran Joined Separate
EC ObjC C++ ObjC++ Undocumented Var(flag_preprocess_only)
EDriver
EFortran Undocumented
EnumName(asm_dialect) Type(enum asm_dialect)Known assembler dialects (for use with the -masm-dialect= option):
EnumName(calling_abi) Type(enum calling_abi)Known ABIs (for use with the -mabi= option):
EnumName(cmodel) Type(enum cmodel)Known code models (for use with the -mcmodel= option):
EnumName(compressed_debug_sections) Type(int)
EnumName(cpp_normalize_level) Type(int) UnknownError(argument %qs to %<-Wnormalized%> not recognized)
EnumName(diagnostic_color_rule) Type(int)
EnumName(diagnostic_prefixing_rule) Type(int)
EnumName(excess_precision) Type(enum excess_precision) UnknownError(unknown excess precision style %qs)
EnumName(fp_contract_mode) Type(enum fp_contract_mode) UnknownError(unknown floating point contraction style %qs)
EnumName(fpmath_unit) Type(enum fpmath_unit)Valid arguments to -mfpmath=:
EnumName(gfc_convert) Type(enum gfc_convert) UnknownError(Unrecognized option to endianess value: %qs)
EnumName(gfc_fcoarray) Type(enum gfc_fcoarray) UnknownError(Unrecognized option: %qs)
EnumName(gfc_init_local_real) Type(enum gfc_init_local_real) UnknownError(Unrecognized option to floating-point init value: %qs)
EnumName(ira_algorithm) Type(enum ira_algorithm) UnknownError(unknown IRA algorithm %qs)
EnumName(ira_region) Type(enum ira_region) UnknownError(unknown IRA region %qs)
EnumName(ivar_visibility) Type(enum ivar_visibility) UnknownError(unrecognized ivar visibility value %qs)
EnumName(ix86_align_data) Type(enum ix86_align_data)Known data alignment choices (for use with the -malign-data= option):
EnumName(ix86_veclibabi) Type(enum ix86_veclibabi)Known vectorization library ABIs (for use with the -mveclibabi= option):
EnumName(lto_partition_model) Type(enum lto_partition_model) UnknownError(unknown LTO partitioning model %qs)
EnumName(offload_abi) Type(enum offload_abi) UnknownError(unknown offload ABI %qs)
EnumName(pmode) Type(enum pmode)Known address mode (for use with the -maddress-mode= option):
EnumName(stack_protector_guard) Type(enum stack_protector_guard)Known stack protector guard (for use with the -mstack-protector-guard= option):
EnumName(stack_reuse_level) Type(enum stack_reuse_level) UnknownError(unknown Stack Reuse Level %qs)
EnumName(stringop_alg) Type(enum stringop_alg)Valid arguments to -mstringop-strategy=:
EnumName(symbol_visibility) Type(enum symbol_visibility) UnknownError(unrecognized visibility value %qs)
EnumName(tls_dialect) Type(enum tls_dialect)Known TLS dialects (for use with the -mtls-dialect= option):
EnumName(tls_model) Type(enum tls_model) UnknownError(unknown TLS model %qs)
EnumName(vect_cost_model) Type(enum vect_cost_model) UnknownError(unknown vectorizer cost model %qs)
EnumName(vtv_priority) Type(enum vtv_priority) UnknownError(unknown vtable verify initialization priority %qs)
EnumValueEnum(asm_dialect) String(att) Value(ASM_ATT)
EnumValueEnum(asm_dialect) String(intel) Value(ASM_INTEL)
EnumValueEnum(calling_abi) String(ms) Value(MS_ABI)
EnumValueEnum(calling_abi) String(sysv) Value(SYSV_ABI)
EnumValueEnum(cmodel) String(32) Value(CM_32)
EnumValueEnum(cmodel) String(kernel) Value(CM_KERNEL)
EnumValueEnum(cmodel) String(large) Value(CM_LARGE)
EnumValueEnum(cmodel) String(medium) Value(CM_MEDIUM)
EnumValueEnum(cmodel) String(small) Value(CM_SMALL)
EnumValueEnum(compressed_debug_sections) String(none) Value(0)
EnumValueEnum(compressed_debug_sections) String(zlib) Value(1)
EnumValueEnum(compressed_debug_sections) String(zlib-gnu) Value(2)
EnumValueEnum(cpp_normalize_level) String(id) Value(normalized_identifier_C)
EnumValueEnum(cpp_normalize_level) String(nfc) Value(normalized_C)
EnumValueEnum(cpp_normalize_level) String(nfkc) Value(normalized_KC)
EnumValueEnum(cpp_normalize_level) String(none) Value(normalized_none)
EnumValueEnum(diagnostic_color_rule) String(always) Value(DIAGNOSTICS_COLOR_YES)
EnumValueEnum(diagnostic_color_rule) String(auto) Value(DIAGNOSTICS_COLOR_AUTO)
EnumValueEnum(diagnostic_color_rule) String(never) Value(DIAGNOSTICS_COLOR_NO)
EnumValueEnum(diagnostic_prefixing_rule) String(every-line) Value(DIAGNOSTICS_SHOW_PREFIX_EVERY_LINE)
EnumValueEnum(diagnostic_prefixing_rule) String(once) Value(DIAGNOSTICS_SHOW_PREFIX_ONCE)
EnumValueEnum(excess_precision) String(fast) Value(EXCESS_PRECISION_FAST)
EnumValueEnum(excess_precision) String(standard) Value(EXCESS_PRECISION_STANDARD)
EnumValueEnum(fp_contract_mode) String(fast) Value(FP_CONTRACT_FAST)
EnumValueEnum(fp_contract_mode) String(off) Value(FP_CONTRACT_OFF)
EnumValueEnum(fp_contract_mode) String(on) Value(FP_CONTRACT_OFF)
EnumValueEnum(fpmath_unit) String(387) Value(FPMATH_387)
EnumValueEnum(fpmath_unit) String(387+sse) Value({(enum fpmath_unit) (FPMATH_SSE | FPMATH_387)})
EnumValueEnum(fpmath_unit) String(387,sse) Value({(enum fpmath_unit) (FPMATH_SSE | FPMATH_387)})
EnumValueEnum(fpmath_unit) String(both) Value({(enum fpmath_unit) (FPMATH_SSE | FPMATH_387)})
EnumValueEnum(fpmath_unit) String(sse) Value(FPMATH_SSE)
EnumValueEnum(fpmath_unit) String(sse+387) Value({(enum fpmath_unit) (FPMATH_SSE | FPMATH_387)})
EnumValueEnum(fpmath_unit) String(sse,387) Value({(enum fpmath_unit) (FPMATH_SSE | FPMATH_387)})
EnumValueEnum(gfc_convert) String(big-endian) Value(GFC_FLAG_CONVERT_BIG)
EnumValueEnum(gfc_convert) String(little-endian) Value(GFC_FLAG_CONVERT_LITTLE)
EnumValueEnum(gfc_convert) String(native) Value(GFC_FLAG_CONVERT_NATIVE)
EnumValueEnum(gfc_convert) String(swap) Value(GFC_FLAG_CONVERT_SWAP)
EnumValueEnum(gfc_fcoarray) String(lib) Value(GFC_FCOARRAY_LIB)
EnumValueEnum(gfc_fcoarray) String(none) Value(GFC_FCOARRAY_NONE)
EnumValueEnum(gfc_fcoarray) String(single) Value(GFC_FCOARRAY_SINGLE)
EnumValueEnum(gfc_init_local_real) String(-inf) Value(GFC_INIT_REAL_NEG_INF)
EnumValueEnum(gfc_init_local_real) String(inf) Value(GFC_INIT_REAL_INF)
EnumValueEnum(gfc_init_local_real) String(nan) Value(GFC_INIT_REAL_NAN)
EnumValueEnum(gfc_init_local_real) String(snan) Value(GFC_INIT_REAL_SNAN)
EnumValueEnum(gfc_init_local_real) String(zero) Value(GFC_INIT_REAL_ZERO)
EnumValueEnum(ira_algorithm) String(CB) Value(IRA_ALGORITHM_CB)
EnumValueEnum(ira_algorithm) String(priority) Value(IRA_ALGORITHM_PRIORITY)
EnumValueEnum(ira_region) String(all) Value(IRA_REGION_ALL)
EnumValueEnum(ira_region) String(mixed) Value(IRA_REGION_MIXED)
EnumValueEnum(ira_region) String(one) Value(IRA_REGION_ONE)
EnumValueEnum(ivar_visibility) String(package) Value(IVAR_VISIBILITY_PACKAGE)
EnumValueEnum(ivar_visibility) String(private) Value(IVAR_VISIBILITY_PRIVATE)
EnumValueEnum(ivar_visibility) String(protected) Value(IVAR_VISIBILITY_PROTECTED)
EnumValueEnum(ivar_visibility) String(public) Value(IVAR_VISIBILITY_PUBLIC)
EnumValueEnum(ix86_align_data) String(abi) Value(ix86_align_data_type_abi)
EnumValueEnum(ix86_align_data) String(cacheline) Value(ix86_align_data_type_cacheline)
EnumValueEnum(ix86_align_data) String(compat) Value(ix86_align_data_type_compat)
EnumValueEnum(ix86_veclibabi) String(acml) Value(ix86_veclibabi_type_acml)
EnumValueEnum(ix86_veclibabi) String(svml) Value(ix86_veclibabi_type_svml)
EnumValueEnum(lto_partition_model) String(1to1) Value(LTO_PARTITION_1TO1)
EnumValueEnum(lto_partition_model) String(balanced) Value(LTO_PARTITION_BALANCED)
EnumValueEnum(lto_partition_model) String(max) Value(LTO_PARTITION_MAX)
EnumValueEnum(lto_partition_model) String(none) Value(LTO_PARTITION_NONE)
EnumValueEnum(lto_partition_model) String(one) Value(LTO_PARTITION_ONE)
EnumValueEnum(offload_abi) String(ilp32) Value(OFFLOAD_ABI_ILP32)
EnumValueEnum(offload_abi) String(lp64) Value(OFFLOAD_ABI_LP64)
EnumValueEnum(pmode) String(long) Value(PMODE_DI)
EnumValueEnum(pmode) String(short) Value(PMODE_SI)
EnumValueEnum(stack_protector_guard) String(global) Value(SSP_GLOBAL)
EnumValueEnum(stack_protector_guard) String(tls) Value(SSP_TLS)
EnumValueEnum(stack_reuse_level) String(all) Value(SR_ALL)
EnumValueEnum(stack_reuse_level) String(named_vars) Value(SR_NAMED_VARS)
EnumValueEnum(stack_reuse_level) String(none) Value(SR_NONE)
EnumValueEnum(stringop_alg) String(byte_loop) Value(loop_1_byte)
EnumValueEnum(stringop_alg) String(libcall) Value(libcall)
EnumValueEnum(stringop_alg) String(loop) Value(loop)
EnumValueEnum(stringop_alg) String(rep_4byte) Value(rep_prefix_4_byte)
EnumValueEnum(stringop_alg) String(rep_8byte) Value(rep_prefix_8_byte)
EnumValueEnum(stringop_alg) String(rep_byte) Value(rep_prefix_1_byte)
EnumValueEnum(stringop_alg) String(unrolled_loop) Value(unrolled_loop)
EnumValueEnum(stringop_alg) String(vector_loop) Value(vector_loop)
EnumValueEnum(symbol_visibility) String(default) Value(VISIBILITY_DEFAULT)
EnumValueEnum(symbol_visibility) String(hidden) Value(VISIBILITY_HIDDEN)
EnumValueEnum(symbol_visibility) String(internal) Value(VISIBILITY_INTERNAL)
EnumValueEnum(symbol_visibility) String(protected) Value(VISIBILITY_PROTECTED)
EnumValueEnum(tls_dialect) String(gnu) Value(TLS_DIALECT_GNU)
EnumValueEnum(tls_dialect) String(gnu2) Value(TLS_DIALECT_GNU2)
EnumValueEnum(tls_model) String(global-dynamic) Value(TLS_MODEL_GLOBAL_DYNAMIC)
EnumValueEnum(tls_model) String(initial-exec) Value(TLS_MODEL_INITIAL_EXEC)
EnumValueEnum(tls_model) String(local-dynamic) Value(TLS_MODEL_LOCAL_DYNAMIC)
EnumValueEnum(tls_model) String(local-exec) Value(TLS_MODEL_LOCAL_EXEC)
EnumValueEnum(vect_cost_model) String(cheap) Value(VECT_COST_MODEL_CHEAP)
EnumValueEnum(vect_cost_model) String(dynamic) Value(VECT_COST_MODEL_DYNAMIC)
EnumValueEnum(vect_cost_model) String(unlimited) Value(VECT_COST_MODEL_UNLIMITED)
EnumValueEnum(vtv_priority) String(none) Value(VTV_NO_PRIORITY)
EnumValueEnum(vtv_priority) String(preinit) Value(VTV_PREINIT_PRIORITY)
EnumValueEnum(vtv_priority) String(std) Value(VTV_STANDARD_PRIORITY)
FDriver C ObjC C++ ObjC++ Joined Separate MissingArgError(missing path after %qs)-F <dir>	Add <dir> to the end of the main framework include path
HC ObjC C++ ObjC++Print the name of header files as they are used
HFortran
HeaderIncludeconfig/i386/i386-opts.h
IAda AdaWhy AdaSCIL Joined Separate
IC ObjC C++ ObjC++ Joined Separate MissingArgError(missing path after %qs)-I <dir>	Add <dir> to the end of the main include path
IFortran Joined Separate
IGo Joined Separate
IJava Joined Separate
JFortran Joined Separate-J<directory>	Put MODULE files in 'directory'
LDriver Joined Separate
LGo Joined Separate
LanguageAda
LanguageAdaSCIL
LanguageAdaWhy
LanguageC
LanguageC++
LanguageFortran
LanguageGo
LanguageJava
LanguageLTO
LanguageObjC
LanguageObjC++
MC ObjC C++ ObjC++Generate make dependencies
MFortran
MJava
MDC ObjC C++ ObjC++ NoDriverArg Separate MissingArgError(missing filename after %qs)Generate make dependencies and compile
MDFortran Separate NoDriverArg
MD_Java Undocumented RejectDriver
MFC ObjC C++ ObjC++ Joined Separate MissingArgError(missing filename after %qs)-MF <file>	Write dependency output to the given file
MFFortran Joined Separate
MFJava Separate
MGC ObjC C++ ObjC++Treat missing header files as generated files
MGFortran
MMC ObjC C++ ObjC++Like -M but ignore system header files
MMFortran
MMJava
MMDC ObjC C++ ObjC++ NoDriverArg Separate MissingArgError(missing filename after %qs)Like -MD but ignore system header files
MMDFortran Separate NoDriverArg
MMD_Java Undocumented RejectDriver
MPC ObjC C++ ObjC++Generate phony targets for all headers
MPFortran
MPJava
MQC ObjC C++ ObjC++ Joined Separate MissingArgError(missing makefile target after %qs)-MQ <target>	Add a MAKE-quoted target
MQFortran Joined Separate
MTC ObjC C++ ObjC++ Joined Separate MissingArgError(missing makefile target after %qs)-MT <target>	Add an unquoted target
MTFortran Joined Separate
MTJava Separate
NDriver
OCommon JoinedOrMissing Optimization-O<number>	Set optimization level to <number>
OfastCommon OptimizationOptimize for speed disregarding exact standards compliance
OgCommon OptimizationOptimize for debugging experience rather than speed or size
OsCommon OptimizationOptimize for space rather than speed
PC ObjC C++ ObjC++Do not generate #line directives
PFortran
QDriver
QnDriver Negative(Qy)
QyDriver Negative(Qn)
RDriver Joined Separate
SDriver
SourceIncludecpplib.h
SourceIncludediagnostic-color.h
SourceIncludepretty-print.h
TDriver Joined Separate
TargetSaveHOST_WIDE_INT x_ix86_isa_flags_explicit
TargetSaveHOST_WIDE_INT x_ix86_target_flags_explicit
TargetSaveconst char *x_ix86_arch_string
TargetSaveconst char *x_ix86_recip_name
TargetSaveconst char *x_ix86_tune_ctrl_string
TargetSaveconst char *x_ix86_tune_memcpy_strategy
TargetSaveconst char *x_ix86_tune_memset_strategy
TargetSaveconst char *x_ix86_tune_string
TargetSaveenum asm_dialect x_ix86_asm_dialect
TargetSaveenum calling_abi x_ix86_abi
TargetSaveenum cmodel x_ix86_cmodel
TargetSaveenum ix86_veclibabi x_ix86_veclibabi_type
TargetSaveenum pmode x_ix86_pmode
TargetSaveenum stack_protector_guard x_ix86_stack_protector_guard
TargetSaveenum stringop_alg x_ix86_stringop_alg
TargetSaveenum tls_dialect x_ix86_tls_dialect
TargetSaveint x_ix86_branch_cost
TargetSaveint x_ix86_dump_tunes
TargetSaveint x_ix86_force_align_arg_pointer
TargetSaveint x_ix86_force_drap
TargetSaveint x_ix86_incoming_stack_boundary_arg
TargetSaveint x_ix86_preferred_stack_boundary_arg
TargetSaveint x_ix86_regparm
TargetSaveint x_ix86_section_threshold
TargetSaveint x_ix86_sse2avx
TargetSaveint x_ix86_tune_no_default
TargetSaveint x_recip_mask_explicit
TargetSaveunsigned char arch
TargetSaveunsigned char arch_specified
TargetSaveunsigned char branch_cost
TargetSaveunsigned char prefetch_sse
TargetSaveunsigned char schedule
TargetSaveunsigned char tune
TargetSaveunsigned char tune_defaulted
TargetVariableint recip_mask = RECIP_MASK_DEFAULT
TbssDriver Separate
Tbss=Driver Joined
TdataDriver Separate
Tdata=Driver Joined
TtextDriver Separate
Ttext=Driver Joined
UC ObjC C++ ObjC++ Joined Separate MissingArgError(macro name missing after %qs)-U<macro>	Undefine <macro>
UFortran Joined Separate
VariableHOST_WIDE_INT frame_larger_than_size
VariableHOST_WIDE_INT ix86_isa_flags = TARGET_64BIT_DEFAULT | TARGET_SUBTARGET_ISA_DEFAULT
VariableHOST_WIDE_INT ix86_isa_flags_explicit
VariableHOST_WIDE_INT larger_than_size
Variablebool dump_base_name_prefixed = false
Variablebool exit_after_options
Variablebool flag_dump_all_passed
Variablebool flag_opts_finished
Variablebool flag_stack_usage_info = false
Variablebool flag_warn_unused_result = false
Variablebool in_lto_p = false
Variablebool use_gnu_debug_info_extensions
Variablebool warn_frame_larger_than
Variablebool warn_larger_than
Variablechar *help_enum_printed
Variablechar *help_printed
Variableconst char *main_input_basename
Variableconst char *main_input_filename
Variableenum debug_info_levels debug_info_level = DINFO_LEVEL_NONE
Variableenum debug_info_type write_symbols = NO_DEBUG
Variableenum debug_struct_file debug_struct_generic[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
Variableenum debug_struct_file debug_struct_ordinary[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
Variableenum stack_check_type flag_stack_check = NO_STACK_CHECK
Variableint *param_values
Variableint flag_complex_method = 1
Variableint flag_debug_asm
Variableint flag_dump_rtl_in_asm
Variableint flag_evaluation_order = 0
Variableint flag_gen_aux_info = 0
Variableint flag_generate_lto
Variableint flag_generate_offload = 0
Variableint flag_print_asm_name
Variableint flag_shlib
Variableint ix86_target_flags_explicit
Variableint main_input_baselength
Variableint optimize
Variableint optimize_debug
Variableint optimize_fast
Variableint optimize_size
Variableint recip_mask_explicit
Variableint rtl_dump_and_exit
Variableint target_flags
Variableunsigned int flag_sanitize
Variableunsigned int flag_sanitize_recover = SANITIZE_UNDEFINED | SANITIZE_NONDEFAULT | SANITIZE_KERNEL_ADDRESS
Variableunsigned int help_columns
Variableunsigned int initial_max_fld_align = TARGET_DEFAULT_PACK_STRUCT
Variablevoid *flag_instrument_functions_exclude_files
Variablevoid *flag_instrument_functions_exclude_functions
WCommon RejectNegative Warning Alias(Wextra)This switch is deprecated; use -Wextra instead
Wa,Driver JoinedOrMissing
WabiC ObjC C++ ObjC++ LTO Var(warn_abi) WarningWarn about things that will change when compiling with an ABI-compliant compiler
Wabi-tagC++ ObjC++ Var(warn_abi_tag) WarningWarn if a subobject has an abi_tag attribute that the complete object type does not have
Wabi=C ObjC C++ ObjC++ LTO Joined RejectNegative UInteger WarningWarn about things that change between the current -fabi-version and the specified version
WaddressC ObjC C++ ObjC++ Var(warn_address) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall)Warn about suspicious uses of memory addresses
Waggregate-returnCommon Var(warn_aggregate_return) WarningWarn about returning structures, unions or arrays
Waggressive-loop-optimizationsCommon Var(warn_aggressive_loop_optimizations) Init(1) WarningWarn if a loop with constant number of iterations triggers undefined behavior
WaliasingFortran Warning Var(warn_aliasing) LangEnabledBy(Fortran,Wall)Warn about possible aliasing of dummy arguments
Walign-commonsFortran Warning Var(warn_align_commons) Init(1)Warn about alignment of COMMON blocks
WallAda AdaWhy AdaSCILEnable most warning messages
WallC ObjC C++ ObjC++ WarningEnable most warning messages
WallFortran
WallGo
WallJava
Wall-deprecationJava
Wall-javadocJava
WampersandFortran Warning Var(warn_ampersand) LangEnabledBy(Fortran,Wall || Wpedantic)Warn about missing ampersand in continued character constants
Warray-boundsCommon Var(warn_array_bounds) WarningWarn if an array is accessed out of bounds
Warray-boundsLangEnabledBy(C ObjC C++ ObjC++,Wall)
Warray-bounds=Common Joined RejectNegative UInteger Var(warn_array_bounds) WarningWarn if an array is accessed out of bounds
Warray-bounds=LangEnabledBy(C ObjC C++ ObjC++,Wall,1,0)
Warray-temporariesFortran Warning Var(warn_array_temporaries)Warn about creation of array temporaries
Wassert-identifierJava
Wassign-interceptObjC ObjC++ Var(warn_assign_intercept) WarningWarn whenever an Objective-C assignment is being intercepted by the garbage collector
WattributesCommon Var(warn_attributes) Init(1) WarningWarn about inappropriate attribute usage
Wbad-function-castC ObjC Var(warn_bad_function_cast) WarningWarn about casting functions to incompatible types
Wbool-compareC ObjC C++ ObjC++ Var(warn_bool_compare) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall)Warn about boolean expression compared with an integer value different from true/false
WboxingJava
Wbuiltin-macro-redefinedC ObjC C++ ObjC++ CPP(warn_builtin_macro_redefined) CppReason(CPP_W_BUILTIN_MACRO_REDEFINED) Var(cpp_warn_builtin_macro_redefined) Init(1) WarningWarn when a built-in preprocessor macro is undefined or redefined
Wc++-compatC ObjC Var(warn_cxx_compat) CPP(warn_cxx_operator_names) CppReason(CPP_W_CXX_OPERATOR_NAMES) Init(0) WarningWarn about C constructs that are not in the common subset of C and C++
Wc++0x-compatC++ ObjC++ Var(warn_cxx0x_compat) Warning LangEnabledBy(C++ ObjC++,Wall)Deprecated in favor of -Wc++11-compat
Wc++11-compatC++ ObjC++ Warning Alias(Wc++0x-compat)Warn about C++ constructs whose meaning differs between ISO C++ 1998 and ISO C++ 2011
Wc++14-compatC++ ObjC++ Var(warn_cxx14_compat) Warning LangEnabledBy(C++ ObjC++,Wall)Warn about C++ constructs whose meaning differs between ISO C++ 2011 and ISO C++ 2014
Wc-binding-typeFortran Var(warn_c_binding_type) Warning LangEnabledBy(Fortran,Wall)Warn if the type of a variable might be not interoperable with C
Wc90-c99-compatC ObjC CPP(cpp_warn_c90_c99_compat) CppReason(CPP_W_C90_C99_COMPAT) Var(warn_c90_c99_compat) Init(-1) WarningWarn about features not present in ISO C90, but present in ISO C99
Wc99-c11-compatC ObjC Var(warn_c99_c11_compat) Init(-1) WarningWarn about features not present in ISO C99, but present in ISO C11
Wcast-alignCommon Var(warn_cast_align) WarningWarn about pointer casts which increase alignment
Wcast-qualC ObjC C++ ObjC++ Var(warn_cast_qual) WarningWarn about casts which discard qualifiers
Wchar-concatJava
Wchar-subscriptsC ObjC C++ ObjC++ Var(warn_char_subscripts) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall)Warn about subscripts whose type is \"char\"
Wcharacter-truncationFortran Var(warn_character_truncation) Warning LangEnabledBy(Fortran,Wall)Warn about truncated character expressions
WchkpC ObjC C++ ObjC++ Var(warn_chkp) Warning EnabledBy(Wall)Warn about memory access errors found by Pointer Bounds Checker
WclobberedC ObjC C++ ObjC++ Var(warn_clobbered) Warning EnabledBy(Wextra)Warn about variables that might be changed by \"longjmp\" or \"vfork\"
WcommentC ObjC C++ ObjC++ CPP(warn_comments) CppReason(CPP_W_COMMENTS) Var(cpp_warn_comment) Init(0) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall)Warn about possibly nested block comments, and C++ comments spanning more than one physical line
WcommentsC ObjC C++ ObjC++ Warning Alias(Wcomment)Synonym for -Wcomment
Wcompare-realsFortran Warning Var(warn_compare_reals) LangEnabledBy(Fortran,Wextra)Warn about equality comparisons involving REAL or COMPLEX expressions
Wcondition-assignJava
Wconditionally-supportedC++ ObjC++ Var(warn_conditionally_supported) WarningWarn for conditionally-supported constructs
Wconstructor-nameJava
WconversionC ObjC C++ ObjC++ Var(warn_conversion) WarningWarn for implicit type conversions that may change a value
WconversionFortran Var(warn_conversion) Warning LangEnabledBy(Fortran,Wall)
Wconversion-extraFortran Var(warn_conversion_extra) WarningWarn about most implicit conversions
Wconversion-nullC++ ObjC++ Var(warn_conversion_null) Init(1) WarningWarn for converting NULL from/to a non-pointer type
Wcoverage-mismatchCommon Var(warn_coverage_mismatch) Init(1) WarningWarn in case profiles in -fprofile-use do not match
WcppC ObjC C++ ObjC++ CppReason(CPP_W_WARNING_DIRECTIVE)
WcppCommon Var(warn_cpp) Init(1) WarningWarn when a #warning directive is encountered
Wctor-dtor-privacyC++ ObjC++ Var(warn_ctor_dtor_privacy) WarningWarn when all constructors and destructors are private
Wdate-timeC ObjC C++ ObjC++ CPP(warn_date_time) CppReason(CPP_W_DATE_TIME) Var(cpp_warn_date_time) Init(0) WarningWarn about __TIME__, __DATE__ and __TIMESTAMP__ usage
Wdate-timeFortran
Wdeclaration-after-statementC ObjC Var(warn_declaration_after_statement) Init(-1) WarningWarn when a declaration is found after a statement
Wdelete-incompleteC++ ObjC++ Var(warn_delete_incomplete) Init(1) WarningWarn when deleting a pointer to incomplete type
Wdelete-non-virtual-dtorC++ ObjC++ Var(warn_delnonvdtor) Warning LangEnabledBy(C++ ObjC++,Wall || Weffc++)Warn about deleting polymorphic objects with non-virtual destructors
Wdep-annJava
WdeprecatedC C++ ObjC ObjC++ CPP(cpp_warn_deprecated) CppReason(CPP_W_DEPRECATED) Var(warn_deprecated) Init(1) WarningWarn if a deprecated compiler feature, class, method, or field is used
WdeprecatedJava Var(warn_deprecated)
Wdeprecated-declarationsCommon Var(warn_deprecated_decl) Init(1) WarningWarn about uses of __attribute__((deprecated)) declarations
Wdesignated-initC ObjC Var(warn_designated_init) Init(1) WarningWarn about positional initialization of structs requiring designated initializers
Wdisabled-optimizationCommon Var(warn_disabled_optimization) WarningWarn when an optimization pass is disabled
Wdiscarded-array-qualifiersC ObjC Var(warn_discarded_array_qualifiers) Init(1) WarningWarn if qualifiers on arrays which are pointer targets are discarded
Wdiscarded-qualifiersC ObjC Var(warn_discarded_qualifiers) Init(1) WarningWarn if type qualifiers on pointers are discarded
WdiscouragedJava
Wdiv-by-zeroC ObjC C++ ObjC++ Var(warn_div_by_zero) Init(1) WarningWarn about compile-time integer division by zero
Wdouble-promotionC ObjC C++ ObjC++ Var(warn_double_promotion) WarningWarn about implicit conversions from \"float\" to \"double\"
Weffc++C++ ObjC++ Var(warn_ecpp) WarningWarn about violations of Effective C++ style rules
Wempty-blockJava
Wempty-bodyC ObjC C++ ObjC++ Var(warn_empty_body) Warning EnabledBy(Wextra)Warn about an empty body in an if or else statement
Wendif-labelsC ObjC C++ ObjC++ CPP(warn_endif_labels) CppReason(CPP_W_ENDIF_LABELS) Var(cpp_warn_endif_labels) Init(1) Warning LangEnabledBy(C ObjC C++ ObjC++,Wpedantic)Warn about stray tokens after #elif and #endif
Wenum-compareC ObjC C++ ObjC++ Var(warn_enum_compare) Init(-1) Warning LangEnabledBy(C ObjC,Wall || Wc++-compat)Warn about comparison of different enum types
Wenum-identifierJava
Wenum-switchJava
WerrorC ObjC C++ ObjC++
WerrorCommon Var(warnings_are_errors)Treat all warnings as errors
Werror-implicit-function-declarationC ObjC RejectNegative Warning Alias(Werror=, implicit-function-declaration)This switch is deprecated; use -Werror=implicit-function-declaration instead
Werror=Common JoinedTreat specified warning as error
WextraCommon Var(extra_warnings) WarningPrint extra (possibly unwanted) warnings
WextraFortran Warning
Wextraneous-semicolonJava Var(flag_extraneous_semicolon)Warn if deprecated empty statements are found
WfallthroughJava
Wfatal-errorsCommon Var(flag_fatal_errors)Exit on the first error occurred
Wfield-hidingJava
Wfinal-boundJava
WfinallyJava
Wfloat-conversionC ObjC C++ ObjC++ Var(warn_float_conversion) LangEnabledBy(C ObjC C++ ObjC++,Wconversion)Warn for implicit type conversions that cause loss of floating point precision
Wfloat-equalC ObjC C++ ObjC++ Var(warn_float_equal) WarningWarn if testing floating point numbers for equality
WforbiddenJava
WformatC ObjC C++ ObjC++ Warning Alias(Wformat=, 1, 0)Warn about printf/scanf/strftime/strfmon format string anomalies
Wformat-contains-nulC ObjC C++ ObjC++ Var(warn_format_contains_nul) Warning LangEnabledBy(C ObjC C++ ObjC++,Wformat=, warn_format >= 1, 0)Warn about format strings that contain NUL bytes
Wformat-extra-argsC ObjC C++ ObjC++ Var(warn_format_extra_args) Warning LangEnabledBy(C ObjC C++ ObjC++,Wformat=, warn_format >= 1, 0)Warn if passing too many arguments to a function for its format string
Wformat-nonliteralC ObjC C++ ObjC++ Var(warn_format_nonliteral) Warning LangEnabledBy(C ObjC C++ ObjC++,Wformat=, warn_format >= 2, 0)Warn about format strings that are not literals
Wformat-securityC ObjC C++ ObjC++ Var(warn_format_security) Warning LangEnabledBy(C ObjC C++ ObjC++,Wformat=, warn_format >= 2, 0)Warn about possible security problems with format functions
Wformat-signednessC ObjC C++ ObjC++ Var(warn_format_signedness) WarningWarn about sign differences with format functions
Wformat-y2kC ObjC C++ ObjC++ Var(warn_format_y2k) Warning LangEnabledBy(C ObjC C++ ObjC++,Wformat=,warn_format >= 2, 0)Warn about strftime formats yielding 2-digit years
Wformat-zero-lengthC ObjC C++ ObjC++ Var(warn_format_zero_length) Warning LangEnabledBy(C ObjC C++ ObjC++,Wformat=,warn_format >= 1, 0)Warn about zero-length formats
Wformat=C ObjC C++ ObjC++ Joined RejectNegative UInteger Var(warn_format) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall, 1, 0)Warn about printf/scanf/strftime/strfmon format string anomalies
Wframe-larger-than=Common RejectNegative Joined UInteger-Wframe-larger-than=<number>	Warn if a function's stack frame requires more than <number> bytes
Wfree-nonheap-objectCommon Var(warn_free_nonheap_object) Init(1) WarningWarn when attempting to free a non-heap object
Wfunction-eliminationFortran Warning Var(warn_function_elimination)Warn about function call elimination
WhidingJava
Wignored-qualifiersC C++ Var(warn_ignored_qualifiers) Warning EnabledBy(Wextra)Warn whenever type qualifiers are ignored.
WimplicitC ObjC Var(warn_implicit) Warning LangEnabledBy(C ObjC,Wall)Warn about implicit declarations
Wimplicit-function-declarationC ObjC Var(warn_implicit_function_declaration) Init(-1) Warning LangEnabledBy(C ObjC,Wimplicit)Warn about implicit function declarations
Wimplicit-intC ObjC Var(warn_implicit_int) Init(-1) Warning LangEnabledBy(C ObjC,Wimplicit)Warn when a declaration does not specify a type
Wimplicit-interfaceFortran Warning Var(warn_implicit_interface)Warn about calls with implicit interface
Wimplicit-procedureFortran Warning Var(warn_implicit_procedure)Warn about called procedures not explicitly declared
WimportC ObjC C++ ObjC++ Undocumented Ignore
Wincompatible-pointer-typesC ObjC Var(warn_incompatible_pointer_types) Init(1) WarningWarn when there is a conversion between pointers that have incompatible types
Windirect-staticJava
Winherited-variadic-ctorC++ ObjC++ Var(warn_inh_var_ctor) Init(1) WarningWarn about C++11 inheriting constructors when the base has a variadic constructor
Winit-selfC ObjC C++ ObjC++ Var(warn_init_self) Warning LangEnabledBy(C++ ObjC++,Wall)Warn about variables which are initialized to themselves
WinlineCommon Var(warn_inline) WarningWarn when an inlined function cannot be inlined
Wint-conversionC ObjC Var(warn_int_conversion) Init(1) WarningWarn about incompatible integer to pointer and pointer to integer conversions
Wint-to-pointer-castC ObjC C++ ObjC++ Var(warn_int_to_pointer_cast) Init(1) WarningWarn when there is a cast to a pointer from an integer of a different size
Wintf-annotationJava
Wintf-non-inheritedJava
Wintrinsic-shadowFortran Warning Var(warn_intrinsic_shadow) LangEnabledBy(Fortran,Wall)Warn if a user-procedure has the same name as an intrinsic
Wintrinsics-stdFortran Var(warn_intrinsics_std) Warning LangEnabledBy(Fortran,Wall)Warn on intrinsics not part of the selected standard
Winvalid-memory-modelCommon Var(warn_invalid_memory_model) Init(1) WarningWarn when an atomic memory model parameter is known to be outside the valid range.
Winvalid-offsetofC++ ObjC++ Var(warn_invalid_offsetof) Init(1) WarningWarn about invalid uses of the \"offsetof\" macro
Winvalid-pchC ObjC C++ ObjC++ CPP(warn_invalid_pch) CppReason(CPP_W_INVALID_PCH) Var(cpp_warn_invalid_pch) Init(0) WarningWarn about PCH files that are found but not used
WjavadocJava
Wjump-misses-initC ObjC Var(warn_jump_misses_init) Warning LangEnabledby(C ObjC,Wc++-compat)Warn when a jump misses a variable initialization
Wl,Driver JoinedOrMissing
Wlarger-than-Common RejectNegative Joined Warning Undocumented Alias(Wlarger-than=)
Wlarger-than=Common RejectNegative Joined UInteger Warning-Wlarger-than=<number>	Warn if an object is larger than <number> bytes
Wline-truncationFortran Warning Var(warn_line_truncation) LangEnabledBy(Fortran,Wall) Init(-1)Warn about truncated source lines
Wliteral-suffixC++ ObjC++ CPP(warn_literal_suffix) CppReason(CPP_W_LITERAL_SUFFIX) Var(cpp_warn_literal_suffix) Init(1) WarningWarn when a string or character literal is followed by a ud-suffix which does not begin with an underscore.
Wlocal-hidingJava
Wlogical-not-parenthesesC ObjC C++ ObjC++ Var(warn_logical_not_paren) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall)Warn when logical not is used on the left hand side operand of a comparison
Wlogical-opC ObjC C++ ObjC++ Var(warn_logical_op) Init(0) Warning Warn when a logical operator is suspiciously always evaluating to true or false
Wlong-longC ObjC C++ ObjC++ CPP(cpp_warn_long_long) CppReason(CPP_W_LONG_LONG) Var(warn_long_long) Init(-1) Warning LangEnabledBy(C ObjC,Wc90-c99-compat)Do not warn about using \"long long\" when -pedantic
WmainC ObjC C++ ObjC++ Var(warn_main) Init(-1) Warning LangEnabledBy(C ObjC,Wall, 2, 0)Warn about suspicious declarations of \"main\"
WmainLangEnabledBy(C ObjC C++ ObjC++,Wpedantic, 2, 0)
Wmasked-catch-blockJava
Wmaybe-uninitializedC ObjC C++ ObjC++ LangEnabledBy(C ObjC C++ ObjC++,Wall)
Wmaybe-uninitializedCommon Var(warn_maybe_uninitialized) Warning EnabledBy(Wuninitialized)Warn about maybe uninitialized automatic variables
Wmaybe-uninitializedFortran LangEnabledBy(Fortran,Wall)
Wmemset-transposed-argsC ObjC C++ ObjC++ Var(warn_memset_transposed_args) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall)Warn about suspicious calls to memset where the third argument is constant literal zero and the second is not
Wmissing-bracesC ObjC C++ ObjC++ Var(warn_missing_braces) Warning LangEnabledBy(C ObjC,Wall)Warn about possibly missing braces around initializers
Wmissing-declarationsC ObjC C++ ObjC++ Var(warn_missing_declarations) WarningWarn about global functions without previous declarations
Wmissing-field-initializersC ObjC C++ ObjC++ Var(warn_missing_field_initializers) Warning EnabledBy(Wextra)Warn about missing fields in struct initializers
Wmissing-format-attributeC ObjC C++ ObjC++ Alias(Wsuggest-attribute=format)
Wmissing-include-dirsC ObjC C++ ObjC++ CPP(warn_missing_include_dirs) CppReason(CPP_W_MISSING_INCLUDE_DIRS) Var(cpp_warn_missing_include_dirs) Init(0) WarningWarn about user-specified include directories that do not exist
Wmissing-include-dirsFortran
Wmissing-noreturnCommon Alias(Wsuggest-attribute=noreturn)
Wmissing-parameter-typeC ObjC Var(warn_missing_parameter_type) Warning EnabledBy(Wextra)Warn about function parameters declared without a type specifier in K&R-style functions
Wmissing-prototypesC ObjC Var(warn_missing_prototypes) WarningWarn about global functions without prototypes
WmudflapC ObjC C++ ObjC++ Ignore Warn(switch %qs is no longer supported)
WmulticharC ObjC C++ ObjC++ CPP(warn_multichar) CppReason(CPP_W_MULTICHAR) Var(cpp_warn_multichar) Init(0) WarningWarn about use of multi-character character constants
WnarrowingC ObjC C++ ObjC++ Warning Var(warn_narrowing) Init(-1) LangEnabledBy(C++ ObjC++,Wall || Wc++0x-compat)Warn about narrowing conversions within { } that are ill-formed in C++11
Wnested-externsC ObjC Var(warn_nested_externs) WarningWarn about \"extern\" declarations not at file scope
WnlsJava
Wno-effect-assignJava
WnoexceptC++ ObjC++ Var(warn_noexcept) WarningWarn when a noexcept expression evaluates to false even though the expression can't actually throw
Wnon-template-friendC++ ObjC++ Var(warn_nontemplate_friend) Init(1) WarningWarn when non-templatized friend functions are declared within a template
Wnon-virtual-dtorC++ ObjC++ Var(warn_nonvdtor) Warning LangEnabledBy(C++ ObjC++,Weffc++)Warn about non-virtual destructors
WnonnullC ObjC C++ ObjC++ LangEnabledBy(C ObjC C++ ObjC++,Wall)
WnonnullC ObjC C++ ObjC++ Var(warn_nonnull) Warning LangEnabledBy(C ObjC C++ ObjC++,Wformat=,warn_format >= 1,0)Warn about NULL being passed to argument slots marked as requiring non-NULL
WnormalizedC ObjC C++ ObjC++ Alias(Wnormalized=,nfc,none)
Wnormalized=C ObjC C++ ObjC++ RejectNegative Joined Warning CPP(warn_normalize) CppReason(CPP_W_NORMALIZE) Init(normalized_C) Var(cpp_warn_normalize) Enum(cpp_normalize_level)-Wnormalized=<none|id|nfc|nfkc>	Warn about non-normalised Unicode strings
WnullJava
WodrCommon Var(warn_odr_violations) Init(1) WarningWarn about some C++ One Definition Rule violations during link time optimization
Wold-style-castC++ ObjC++ Var(warn_old_style_cast) WarningWarn if a C-style cast is used in a program
Wold-style-declarationC ObjC Var(warn_old_style_declaration) Warning EnabledBy(Wextra)Warn for obsolescent usage in a declaration
Wold-style-definitionC ObjC Var(warn_old_style_definition) WarningWarn if an old-style parameter definition is used
Wopenmp-simdC C++ Var(warn_openmp_simd) Warning LangEnabledBy(C C++,Wall)Warn if a simd directive is overridden by the vectorizer cost model
Wopenmp-simdFortran
Wout-of-dateJava Var(flag_newer) Init(1)Warn if .class files are out of date
Wover-annJava
WoverflowCommon Var(warn_overflow) Init(1) WarningWarn about overflow in arithmetic expressions
Woverlength-stringsC ObjC C++ ObjC++ Var(warn_overlength_strings) Warning LangEnabledBy(C ObjC C++ ObjC++,Wpedantic)Warn if a string is longer than the maximum portable length specified by the standard
Woverloaded-virtualC++ ObjC++ Var(warn_overloaded_virtual) WarningWarn about overloaded virtual function names
Woverride-initC ObjC Var(warn_override_init) Warning EnabledBy(Wextra)Warn about overriding initializers without side effects
Wp,Driver JoinedOrMissing
WpackedCommon Var(warn_packed) WarningWarn when the packed attribute has no effect on struct layout
Wpacked-bitfield-compatC ObjC C++ ObjC++ Var(warn_packed_bitfield_compat) Init(-1) WarningWarn about packed bit-fields whose offset changed in GCC 4.4
WpaddedCommon Var(warn_padded) WarningWarn when padding is required to align structure members
Wparam-assignJava
WparenthesesC ObjC C++ ObjC++ Var(warn_parentheses) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall)Warn about possibly missing parentheses
WpedanticC ObjC C++ ObjC++ CPP(cpp_pedantic) CppReason(CPP_W_PEDANTIC) Warning
WpedanticCommon Var(pedantic) Init(0) WarningIssue warnings needed for strict compliance to the standard
WpedanticFortran
Wpkg-default-methodJava
Wpmf-conversionsC++ ObjC++ Var(warn_pmf2ptr) Init(1) WarningWarn when converting the type of pointers to member functions
Wpointer-arithC ObjC C++ ObjC++ Var(warn_pointer_arith) Warning LangEnabledBy(C ObjC C++ ObjC++,Wpedantic)Warn about function pointer arithmetic
Wpointer-signC ObjC Var(warn_pointer_sign) Warning LangEnabledBy(C ObjC,Wall || Wpedantic)Warn when a pointer differs in signedness in an assignment
Wpointer-to-int-castC ObjC Var(warn_pointer_to_int_cast) Init(1) WarningWarn when a pointer is cast to an integer of a different size
WpragmasC ObjC C++ ObjC++ Var(warn_pragmas) Init(1) WarningWarn about misuses of pragmas
Wproperty-assign-defaultObjC ObjC++ Var(warn_property_assign_default) Init(1) WarningWarn if a property for an Objective-C object has no assign semantics specified
WprotocolObjC ObjC++ Var(warn_protocol) Init(1) WarningWarn if inherited methods are unimplemented
WpsabiC ObjC C++ ObjC++ LTO Var(warn_psabi) Init(1) Undocumented LangEnabledBy(C ObjC C++ ObjC++,Wabi)
WrawJava
Wreal-q-constantFortran Warning Var(warn_real_q_constant) LangEnabledBy(Fortran,Wall)Warn about real-literal-constants with 'q' exponent-letter
Wrealloc-lhsFortran Warning Var(warn_realloc_lhs) LangEnabledBy(Fortran,Wrealloc-lhs-all)Warn when a left-hand-side array variable is reallocated
Wrealloc-lhs-allFortran Warning Var(warn_realloc_lhs_all)Warn when a left-hand-side variable is reallocated
Wredundant-declsC ObjC C++ ObjC++ Var(warn_redundant_decls) WarningWarn about multiple declarations of the same object
Wredundant-modifiersJava Var(flag_redundant)Warn if modifiers are specified when not necessary
WreorderC++ ObjC++ Var(warn_reorder) Warning LangEnabledBy(C++ ObjC++,Wall)Warn when the compiler reorders code
Wreturn-local-addrCommon Var(warn_return_local_addr) Init(1) WarningWarn about returning a pointer/reference to a local or temporary variable.
Wreturn-typeC ObjC C++ ObjC++ Var(warn_return_type) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall)Warn whenever a function's return type defaults to \"int\" (C), or about inconsistent return types (C++)
Wreturn-typeFortran Warning LangEnabledBy(Fortran,Wall)
WselectorObjC ObjC++ Var(warn_selector) WarningWarn if a selector has multiple methods
Wsequence-pointC ObjC C++ ObjC++ Var(warn_sequence_point) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall)Warn about possible violations of sequence point rules
WserialJava
WshadowCommon Var(warn_shadow) WarningWarn when one local variable shadows another
Wshadow-ivarObjC ObjC++ Var(warn_shadow_ivar) EnabledBy(Wshadow) Init(1) WarningWarn if a local declaration hides an instance variable
Wshift-count-negativeC ObjC C++ ObjC++ Var(warn_shift_count_negative) Init(1) WarningWarn if shift count is negative
Wshift-count-overflowC ObjC C++ ObjC++ Var(warn_shift_count_overflow) Init(1) WarningWarn if shift count >= width of type
Wsign-compareC ObjC C++ ObjC++ EnabledBy(Wextra)
Wsign-compareC ObjC C++ ObjC++ Var(warn_sign_compare) Warning LangEnabledBy(C++ ObjC++,Wall)Warn about signed-unsigned comparisons
Wsign-conversionC ObjC C++ ObjC++ Var(warn_sign_conversion) LangEnabledBy(C ObjC,Wconversion)Warn for implicit type conversions between signed and unsigned integers
Wsign-promoC++ ObjC++ Var(warn_sign_promo) WarningWarn when overload promotes from unsigned to signed
Wsized-deallocationC++ ObjC++ Var(warn_sized_deallocation) Warning EnabledBy(Wextra)Warn about missing sized deallocation functions
Wsizeof-array-argumentC ObjC C++ ObjC++ Var(warn_sizeof_array_argument) Warning Init(1)Warn when sizeof is applied on a parameter declared as an array
Wsizeof-pointer-memaccessC ObjC C++ ObjC++ Var(warn_sizeof_pointer_memaccess) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall)Warn about suspicious length parameters to certain string functions if the argument uses sizeof
Wspecial-param-hidingJava
Wstack-protectorCommon Var(warn_stack_protect) WarningWarn when not issuing stack smashing protection for some reason
Wstack-usage=Common Joined RejectNegative UInteger Var(warn_stack_usage) Init(-1) WarningWarn if stack usage might be larger than specified amount
Wstatic-accessJava
Wstatic-receiverJava
Wstrict-aliasingCommon WarningWarn about code which might break strict aliasing rules
Wstrict-aliasing=C ObjC C++ ObjC++ LangEnabledBy(C ObjC C++ ObjC++,Wall, 3, 0)
Wstrict-aliasing=Common Joined RejectNegative UInteger Var(warn_strict_aliasing) WarningWarn about code which might break strict aliasing rules
Wstrict-null-sentinelC++ ObjC++ Warning Var(warn_strict_null_sentinel)Warn about uncasted NULL used as sentinel
Wstrict-overflowCommon WarningWarn about optimizations that assume that signed overflow is undefined
Wstrict-overflow=C ObjC C++ ObjC++ LangEnabledBy(C ObjC C++ ObjC++,Wall, 1, 0)
Wstrict-overflow=Common Joined RejectNegative UInteger Var(warn_strict_overflow) WarningWarn about optimizations that assume that signed overflow is undefined
Wstrict-prototypesC ObjC Var(warn_strict_prototypes) WarningWarn about unprototyped function declarations
Wstrict-selector-matchObjC ObjC++ Var(warn_strict_selector_match) WarningWarn if type signatures of candidate methods do not match exactly
Wsuggest-attribute=constCommon Var(warn_suggest_attribute_const) WarningWarn about functions which might be candidates for __attribute__((const))
Wsuggest-attribute=formatC ObjC C++ ObjC++ Var(warn_suggest_attribute_format) WarningWarn about functions which might be candidates for format attributes
Wsuggest-attribute=noreturnCommon Var(warn_suggest_attribute_noreturn) WarningWarn about functions which might be candidates for __attribute__((noreturn))
Wsuggest-attribute=pureCommon Var(warn_suggest_attribute_pure) WarningWarn about functions which might be candidates for __attribute__((pure))
Wsuggest-final-methodsCommon Var(warn_suggest_final_methods) WarningWarn about C++ virtual methods where adding final keyword would improve code quality
Wsuggest-final-typesCommon Var(warn_suggest_final_types) WarningWarn about C++ polymorphic types where adding final keyword would improve code quality
Wsuggest-overrideC++ ObjC++ Var(warn_override) WarningSuggest that the override keyword be used when the declaration of a virtualfunction overrides another.
WsuppressJava
WsurprisingFortran Warning Var(warn_surprising) LangEnabledBy(Fortran,Wall)Warn about \"suspicious\" constructs
WswitchC ObjC C++ ObjC++ Var(warn_switch) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall)Warn about enumerated switches, with no default, missing a case
Wswitch-boolC ObjC C++ ObjC++ Var(warn_switch_bool) Warning Init(1)Warn about switches with boolean controlling expression
Wswitch-defaultC ObjC C++ ObjC++ Var(warn_switch_default) WarningWarn about enumerated switches missing a \"default:\" statement
Wswitch-enumC ObjC C++ ObjC++ Var(warn_switch_enum) WarningWarn about all enumerated switches missing a specific case
Wsync-nandC C++ Var(warn_sync_nand) Init(1) WarningWarn when __sync_fetch_and_nand and __sync_nand_and_fetch built-in functions are used
WsynthC++ ObjC++ Var(warn_synth) WarningDeprecated.  This switch has no effect
Wsynthetic-accessJava
Wsystem-headersC ObjC C++ ObjC++ Warning
Wsystem-headersCommon Var(warn_system_headers) WarningDo not suppress warnings from system headers
WtabsFortran Warning Var(warn_tabs) LangEnabledBy(Fortran,Wall || Wpedantic)Permit nonconforming uses of the tab character
Wtarget-lifetimeFortran Warning Var(warn_target_lifetime) LangEnabledBy(Fortran,Wall)Warn if the pointer in a pointer assignment might outlive its target
WtasksJava
WtraditionalC ObjC CPP(cpp_warn_traditional) CppReason(CPP_W_TRADITIONAL) Var(warn_traditional) Init(0) WarningWarn about features not present in traditional C
Wtraditional-conversionC ObjC Var(warn_traditional_conversion) WarningWarn of prototypes causing type conversions different from what would happen in the absence of prototype
WtrampolinesCommon Var(warn_trampolines) WarningWarn whenever a trampoline is generated
WtrigraphsC ObjC C++ ObjC++ CPP(warn_trigraphs) CppReason(CPP_W_TRIGRAPHS) Var(cpp_warn_trigraphs) Init(2) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall)Warn if trigraphs are encountered that might affect the meaning of the program
Wtype-hidingJava
Wtype-limitsCommon Var(warn_type_limits) Warning EnabledBy(Wextra)Warn if a comparison is always true or always false due to the limited range of the data type
WuncheckJava
Wundeclared-selectorObjC ObjC++ Var(warn_undeclared_selector) WarningWarn about @selector()s without previously declared methods
WundefC ObjC C++ ObjC++ CPP(warn_undef) CppReason(CPP_W_UNDEF) Var(cpp_warn_undef) Init(0) WarningWarn if an undefined macro is used in an #if directive
WunderflowFortran Warning Var(warn_underflow) Init(1)Warn about underflow of numerical constant expressions
WuninitializedC ObjC C++ ObjC++ LangEnabledBy(C ObjC C++ ObjC++,Wall)
WuninitializedCommon Var(warn_uninitialized) Warning EnabledBy(Wextra)Warn about uninitialized automatic variables
WuninitializedFortran LangEnabledBy(Fortran,Wall)
Wunknown-pragmasC ObjC C++ ObjC++ Warning Var(warn_unknown_pragmas) LangEnabledBy(C ObjC C++ ObjC++,Wall, 1, 0)Warn about unrecognized pragmas
Wunnecessary-elseJava
Wunqualified-fieldJava
Wunreachable-codeCommon IgnoreDoes nothing. Preserved for backward compatibility.
Wunsafe-loop-optimizationsCommon Var(warn_unsafe_loop_optimizations) WarningWarn if the loop cannot be optimized due to nontrivial assumptions.
Wunsuffixed-float-constantsC ObjC Var(warn_unsuffixed_float_constants) WarningWarn about unsuffixed float constants
WunusedC ObjC C++ ObjC++ LangEnabledBy(C ObjC C++ ObjC++,Wall)
WunusedCommon Var(warn_unused) Init(0) WarningEnable all -Wunused- warnings
WunusedJava
WunusedLangEnabledBy(Fortran,Wall)
Wunused-argumentJava
Wunused-but-set-parameterCommon Var(warn_unused_but_set_parameter) Warning EnabledBy(Wunused && Wextra)Warn when a function parameter is only set, otherwise unused
Wunused-but-set-variableCommon Var(warn_unused_but_set_variable) Warning EnabledBy(Wunused)Warn when a variable is only set, otherwise unused
Wunused-dummy-argumentFortran Warning Var(warn_unused_dummy_argument) LangEnabledBy(Fortran,Wall)Warn about unused dummy arguments.
Wunused-functionCommon Var(warn_unused_function) Warning EnabledBy(Wunused)Warn when a function is unused
Wunused-importJava
Wunused-labelCommon Var(warn_unused_label) Warning EnabledBy(Wunused)Warn when a label is unused
Wunused-labelJava
Wunused-localJava
Wunused-local-typedefsC ObjC C++ ObjC++ Var(warn_unused_local_typedefs) Warning EnabledBy(Wunused)Warn when typedefs locally defined in a function are not used
Wunused-macrosC ObjC C++ ObjC++ CppReason(CPP_W_UNUSED_MACROS) Var(cpp_warn_unused_macros) WarningWarn about macros defined in the main file that are not used
Wunused-parameterCommon Var(warn_unused_parameter) Warning EnabledBy(Wunused && Wextra)Warn when a function parameter is unused
Wunused-privateJava
Wunused-resultC ObjC C++ ObjC++ Var(warn_unused_result) Init(1) WarningWarn if a caller of a function, marked with attribute warn_unused_result, does not use its return value
Wunused-thrownJava
Wunused-valueCommon Var(warn_unused_value) Warning EnabledBy(Wunused)Warn when an expression value is unused
Wunused-variableCommon Var(warn_unused_variable) Warning EnabledBy(Wunused)Warn when a variable is unused
Wuse-without-onlyFortran Var(warn_use_without_only) WarningWarn about USE statements that have no ONLY qualifier
Wuseless-castC++ ObjC++ Var(warn_useless_cast) WarningWarn about useless casts
Wuseless-type-checkJava
WvarargsC ObjC C++ ObjC++ Warning Var(warn_varargs) Init(1)Warn about questionable usage of the macros used to retrieve variable arguments
Wvarargs-castJava
Wvariadic-macrosC ObjC C++ ObjC++ CPP(warn_variadic_macros) CppReason(CPP_W_VARIADIC_MACROS) Var(cpp_warn_variadic_macros) Init(0) Warning LangEnabledBy(C ObjC C++ ObjC++,Wpedantic || Wtraditional)Warn about using variadic macros
Wvector-operation-performanceCommon Var(warn_vector_operation_performance) WarningWarn when a vector operation is compiled outside the SIMD
Wvirtual-move-assignC++ ObjC++ Var(warn_virtual_move_assign) Warning Init(1)Warn if a virtual base has a non-trivial move assignment operator
WvlaC ObjC C++ ObjC++ Var(warn_vla) Init(-1) WarningWarn if a variable length array is used
Wvolatile-register-varC ObjC C++ ObjC++ Var(warn_volatile_register_var) Warning LangEnabledBy(C ObjC C++ ObjC++,Wall)Warn when a register variable is declared volatile
Wwarning-tokenJava
Wwrite-stringsC ObjC C++ ObjC++ Var(warn_write_strings) WarningIn 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.
Wzero-as-null-pointer-constantC++ ObjC++ Var(warn_zero_as_null_pointer_constant) WarningWarn when a literal '0' is used as null pointer
WzerotripFortran Warning Var(warn_zerotrip) LangEnabledBy(Fortran,Wall)Warn about zero-trip DO loops
XassemblerDriver Separate
XlinkerDriver Separate
XpreprocessorDriver Separate
ZDriver
ansiC ObjC C++ ObjC++A synonym for -std=c89 (for C) or -std=c++98 (for C++)
aux-infoCommon Separate Var(aux_info_file_name)-aux-info <file>	Emit declaration information into <file>
aux-info=Common Joined Alias(aux-info)
auxbaseCommon Separate RejectDriver Var(aux_base_name)
auxbase-stripCommon Separate RejectDriver
bootclasspathJava Separate Alias(fbootclasspath=)
cDriver
classpathJava Separate Alias(fclasspath=)
coverageDriver
cppFortran Negative(nocpp)Enable preprocessing
cpp=Fortran Joined Negative(nocpp) Undocumented NoDWARFRecord
dC ObjC C++ ObjC++ Joined
dCommon Joined-d<letters>	Enable dumps from specific passes of the compiler
dFortran Joined
dJava Separate SeparateAlias Alias(foutput-class-dir=)
dumpbaseCommon Separate Var(dump_base_name)-dumpbase <file>	Set the file basename to be used for dumps
dumpdirCommon Separate Var(dump_dir_name)-dumpdir <dir>	Set the directory name to be used for dumps
dumpmachineDriver
dumpspecsDriver
dumpversionDriver
eDriver Joined Separate
encodingJava Separate Alias(fencoding=)
export-dynamicDriver Undocumented
extdirsDriver Separate
fCLASSPATH=Java JoinedOrMissing RejectNegative Alias(fclasspath=)--CLASSPATH	Deprecated; use --classpath instead
fPICCommon Report Var(flag_pic,2) Negative(fPIE)Generate position-independent code if possible (large mode)
fPIECommon Report Var(flag_pie,2) Negative(fpic)Generate position-independent code for executables if possible (large mode)
fRTS=Ada AdaWhy AdaSCIL Joined RejectNegativeSelect the runtime
fabi-compat-version=C++ ObjC++ Joined RejectNegative UInteger Var(flag_abi_compat_version) Init(-1)The version of the C++ ABI used for -Wabi warnings and link compatibility aliases
fabi-version=Common Joined RejectNegative UInteger Var(flag_abi_version) Init(0)The version of the C++ ABI in use
faccess-controlC++ ObjC++ Var(flag_access_control) Init(1)Enforce class member access control semantics
fada-spec-parent=C ObjC C++ ObjC++ RejectNegative Joined Var(ada_specs_parent)-fada-spec-parent=unit  Dump Ada specs as child units of given parent
faggressive-function-eliminationFortran Var(flag_aggressive_function_elimination)Eliminate multiple function invokations also for impure functions
faggressive-loop-optimizationsCommon Report Var(flag_aggressive_loop_optimizations) Optimization Init(1) Aggressively optimize loops using language constraints
falign-commonsFortran Var(flag_align_commons) Init(1)Enable alignment of COMMON blocks
falign-functionsCommon Report Var(align_functions,0) Optimization UIntegerAlign the start of functions
falign-functions=Common RejectNegative Joined UInteger Var(align_functions)
falign-jumpsCommon Report Var(align_jumps,0) Optimization UIntegerAlign labels which are only reached by jumping
falign-jumps=Common RejectNegative Joined UInteger Var(align_jumps)
falign-labelsCommon Report Var(align_labels,0) Optimization UIntegerAlign all labels
falign-labels=Common RejectNegative Joined UInteger Var(align_labels)
falign-loopsCommon Report Var(align_loops,0) Optimization UIntegerAlign the start of loops
falign-loops=Common RejectNegative Joined UInteger Var(align_loops)
fall-intrinsicsFortran RejectNegative Var(flag_all_intrinsics)All intrinsics procedures are available regardless of selected standard
fall-virtualC++ ObjC++ Ignore Warn(switch %qs is no longer supported)
fallow-leading-underscoreFortran Undocumented Var(flag_allow_leading_underscore)
fallow-parameterless-variadic-functionsC ObjC Var(flag_allow_parameterless_variadic_functions)Allow variadic functions without named parameter
falt-external-templatesC++ ObjC++ Ignore Warn(switch %qs is no longer supported)No longer supported
fargument-aliasCommon IgnoreDoes nothing. Preserved for backward compatibility.
fargument-noaliasCommon IgnoreDoes nothing. Preserved for backward compatibility.
fargument-noalias-anythingCommon IgnoreDoes nothing. Preserved for backward compatibility.
fargument-noalias-globalCommon IgnoreDoes nothing. Preserved for backward compatibility.
fasan-shadow-offset=Common Joined RejectNegative Var(common_deferred_options) Defer-fasan-shadow-offset=<number>	Use custom shadow memory offset.
fasmC ObjC C++ ObjC++ Var(flag_no_asm, 0)Recognize the \"asm\" keyword
fassertJava Var(flag_assert) Init(1)Permit the use of the assert keyword
fassociative-mathCommon Report Var(flag_associative_math) SetByCombined OptimizationAllow optimization for floating-point arithmetic which may change theresult of the operation due to rounding.
fassume-compiledJava
fassume-compiled=Java JoinedOrMissing
fasynchronous-unwind-tablesCommon Report Var(flag_asynchronous_unwind_tables) OptimizationGenerate unwind tables that are exact at each instruction boundary
fauto-inc-decCommon Report Var(flag_auto_inc_dec) Init(1) OptimizationGenerate auto-inc/dec instructions
fauto-profileCommon Report Var(flag_auto_profile)Use sample profile information for call graph node weights. The defaultprofile file is fbdata.afdo in 'pwd'.
fauto-profile=Common Joined RejectNegative Var(auto_profile_file)Use sample profile information for call graph node weights. The profilefile is specified in the argument.
fautomaticFortran Var(flag_automatic) Init(1)Do not treat local variables and COMMON blocks as if they were named in SAVE statements
faux-classpathJava Separate RejectNegative Undocumented
fbackslashFortran Var(flag_backslash)Specify that backslash in string introduces an escape character
fbacktraceFortran Var(flag_backtrace) Init(1)Produce a backtrace when a runtime error is encountered
fblas-matmul-limit=Fortran RejectNegative Joined UInteger Var(flag_blas_matmul_limit) Init(30)-fblas-matmul-limit=<n>	Size of the smallest matrix for which matmul will use BLAS
fbootclasspath=Java JoinedOrMissing RejectNegative--bootclasspath=<path>	Replace system path
fbootstrap-classesJava Var(flag_bootstrap_classes)Generated should be loaded by bootstrap loader
fbounds-checkCommon Report Var(flag_bounds_check)Generate code to check bounds before indexing arrays
fbranch-count-regCommon Report Var(flag_branch_on_count_reg) OptimizationReplace add, compare, branch with branch on count register
fbranch-probabilitiesCommon Report Var(flag_branch_probabilities) OptimizationUse profiling information for branch probabilities
fbranch-target-load-optimizeCommon Report Var(flag_branch_target_load_optimize) OptimizationPerform branch target load optimization before prologue / epilogue threading
fbranch-target-load-optimize2Common Report Var(flag_branch_target_load_optimize2) OptimizationPerform branch target load optimization after prologue / epilogue threading
fbtr-bb-exclusiveCommon Report Var(flag_btr_bb_exclusive) OptimizationRestrict target load migration not to re-use registers in any basic block
fbuilding-libgccC ObjC C++ ObjC++ Undocumented Var(flag_building_libgcc)
fbuiltinC ObjC C++ ObjC++ Var(flag_no_builtin, 0)Recognize built-in functions
fbuiltin-C ObjC C++ ObjC++ Joined
fcall-saved-Common Joined RejectNegative Var(common_deferred_options) Defer-fcall-saved-<register>	Mark <register> as being preserved across functions
fcall-used-Common Joined RejectNegative Var(common_deferred_options) Defer-fcall-used-<register>	Mark <register> as being corrupted by function calls
fcaller-savesCommon Report Var(flag_caller_saves) OptimizationSave registers around function calls
fcanonical-system-headersC ObjC C++ ObjC++Where shorter, use canonicalized paths to systems headers.
fcheck-array-temporariesFortranProduce a warning at runtime if a array temporary has been created for a procedure argument
fcheck-data-depsCommon Report Var(flag_check_data_deps)Compare the results of several data dependence analyzers.
fcheck-newCommon Var(flag_check_new)Check the return value of new in C++
fcheck-pointer-boundsC ObjC C++ ObjC++ LTO Report Var(flag_check_pointer_bounds)Add Pointer Bounds Checker instrumentation.  fchkp-* flags are used tocontrol instrumentation.  Currently available for C, C++ and ObjC.
fcheck-referencesJava Var(flag_check_references)Generate checks for references to NULL
fcheck=Fortran RejectNegative JoinedOrMissing-fcheck=[...]	Specify which runtime checks are to be performed
fchkp-check-incomplete-typeC ObjC C++ ObjC++ LTO Report Var(flag_chkp_incomplete_type) Init(1)Generate pointer bounds checks for variables with incomplete type
fchkp-check-readC ObjC C++ ObjC++ LTO Report Var(flag_chkp_check_read) Init(1)Generate checks for all read accesses to memory.
fchkp-check-writeC ObjC C++ ObjC++ LTO Report Var(flag_chkp_check_write) Init(1)Generate checks for all write accesses to memory.
fchkp-first-field-has-own-boundsC ObjC C++ ObjC++ LTO RejectNegative Report Var(flag_chkp_first_field_has_own_bounds)Forces Pointer Bounds Checker to use narrowed bounds for address of the firstfield in the structure.  By default pointer to the first field has the samebounds as pointer to the whole structure.
fchkp-instrument-callsC ObjC C++ ObjC++ LTO Report Var(flag_chkp_instrument_calls) Init(1)Generate bounds passing for calls.
fchkp-instrument-marked-onlyC ObjC C++ ObjC++ LTO Report Var(flag_chkp_instrument_marked_only) Init(0)Instrument only functions marked with bnd_instrument attribute.
fchkp-narrow-boundsC ObjC C++ ObjC++ LTO Report Var(flag_chkp_narrow_bounds) Init(1)Control how Pointer Bounds Checker handle pointers to object fields.  Whennarrowing is on, field bounds are used.  Otherwise full object bounds are used.
fchkp-narrow-to-innermost-arrayC ObjC C++ ObjC++ LTO RejectNegative Report Var(flag_chkp_narrow_to_innermost_arrray)Forces Pointer Bounds Checker to use bounds of the innermost arrays in case ofnested static arryas access.  By default outermost array is used.
fchkp-optimizeC ObjC C++ ObjC++ LTO Report Var(flag_chkp_optimize) Init(-1)Allow Pointer Bounds Checker optimizations.  By default allowedon optimization levels >0.
fchkp-store-boundsC ObjC C++ ObjC++ LTO Report Var(flag_chkp_store_bounds) Init(1)Generate bounds stores for pointer writes.
fchkp-treat-zero-dynamic-size-as-infiniteC ObjC C++ ObjC++ LTO Report Var(flag_chkp_zero_dynamic_size_as_infinite) Init(0)With this option zero size obtained dynamically for objects withincomplete type will be treated as infinite.
fchkp-use-fast-string-functionsC ObjC C++ ObjC++ LTO Report Var(flag_chkp_use_fast_string_functions) Init(0)Allow to use *_nobnd versions of string functions by Pointer Bounds Checker.
fchkp-use-nochk-string-functionsC ObjC C++ ObjC++ LTO Report Var(flag_chkp_use_nochk_string_functions) Init(0)Allow to use *_nochk versions of string functions by Pointer Bounds Checker.
fchkp-use-static-boundsC ObjC C++ ObjC++ LTO Report Var(flag_chkp_use_static_bounds) Init(1)Use statically initialized variable for vars bounds instead ofgenerating them each time it is required.
fchkp-use-static-const-boundsC ObjC C++ ObjC++ LTO Report Var(flag_chkp_use_static_const_bounds) Init(-1)Use statically initialized variable for constant bounds instead ofgenerating them each time it is required.
fchkp-use-wrappersC ObjC C++ ObjC++ LTO Report Var(flag_chkp_use_wrappers) Init(1)Transform instrumented builtin calls into calls to wrappers.
fchkp-zero-input-bounds-for-mainC ObjC C++ ObjC++ LTO Report Var(flag_chkp_zero_input_bounds_for_main) Init(0)Use zero bounds for all incoming arguments in 'main' function.  It helps wheninstrumented binaries are used with legacy libs.
fcilkplusC ObjC C++ ObjC++ LTO Report Var(flag_cilkplus) Init(0)Enable Cilk Plus
fclasspath=Java JoinedOrMissing RejectNegative--classpath=<path>	Set class path
fcoarray=Fortran RejectNegative Joined Enum(gfc_fcoarray) Var(flag_coarray) Init(GFC_FCOARRAY_NONE)-fcoarray=<none|single|lib>	Specify which coarray parallelization should be used
fcombine-stack-adjustmentsCommon Report Var(flag_combine_stack_adjustments) OptimizationLooks for opportunities to reduce stack adjustments and stack references.
fcommonCommon Report Var(flag_no_common,0)Do not put uninitialized globals in the common section
fcompare-debugDriver
fcompare-debug-secondCommon Driver RejectNegative Var(flag_compare_debug)Run only the second compilation of -fcompare-debug
fcompare-debug=Common Driver JoinedOrMissing RejectNegative Var(flag_compare_debug_opt)-fcompare-debug[=<opts>]	Compile with and without e.g. -gtoggle, and compare the final-insns dump
fcompare-elimCommon Report Var(flag_compare_elim_after_reload) OptimizationPerform comparison elimination after register allocation has finished
fcompile-resource=Java Joined RejectNegative
fcond-mismatchC ObjC C++ ObjC++Allow the arguments of the '?' operator to have different types
fconserve-spaceC++ ObjC++ Var(flag_conserve_space)Does nothing.  Preserved for backward compatibility.
fconserve-stackCommon Var(flag_conserve_stack) OptimizationDo not perform optimizations increasing noticeably stack usage
fconstant-string-class=ObjC ObjC++ Joined MissingArgError(no class name specified with %qs)-fconst-string-class=<name>	Use class <name> for constant strings
fconstexpr-depth=C++ ObjC++ Joined RejectNegative UInteger Var(max_constexpr_depth) Init(512)-fconstexpr-depth=<number>	Specify maximum constexpr recursion depth
fconvert=Fortran RejectNegative Joined Enum(gfc_convert) Var(flag_convert) Init(GFC_FLAG_CONVERT_NATIVE)-fconvert=<big-endian|little-endian|native|swap> The endianness used for unformatted files.
fcprop-registersCommon Report Var(flag_cprop_registers) OptimizationPerform a register copy-propagation optimization pass
fcray-pointerFortran Var(flag_cray_pointer)Use the Cray Pointer extension
fcrossjumpingCommon Report Var(flag_crossjumping) OptimizationPerform cross-jumping optimization
fcse-follow-jumpsCommon Report Var(flag_cse_follow_jumps) OptimizationWhen running CSE, follow jumps to their targets
fcse-skip-blocksCommon IgnoreDoes nothing.  Preserved for backward compatibility.
fcx-fortran-rulesCommon Report Var(flag_cx_fortran_rules) OptimizationComplex multiplication and division follow Fortran rules
fcx-limited-rangeCommon Report Var(flag_cx_limited_range) Optimization SetByCombinedOmit range reduction step when performing complex division
fd-lines-as-codeFortran RejectNegativeIgnore 'D' in column one in fixed form
fd-lines-as-commentsFortran RejectNegativeTreat lines with 'D' in column one as comments
fdata-sectionsCommon Report Var(flag_data_sections)Place data items into their own section
fdbg-cnt-listCommon Report Var(common_deferred_options) DeferList all available debugging counters with their limits and counts.
fdbg-cnt=Common RejectNegative Joined Var(common_deferred_options) Defer-fdbg-cnt=<counter>:<limit>[,<counter>:<limit>,...]	Set the debug counter limit.   
fdceCommon Var(flag_dce) Init(1) OptimizationUse the RTL dead code elimination pass
fdebug-cppC ObjC C++ ObjC++Emit debug annotations during preprocessing
fdebug-prefix-map=Common Joined RejectNegative Var(common_deferred_options) DeferMap one directory name to another in debug information
fdebug-types-sectionCommon Report Var(flag_debug_types_section) Init(0)Output .debug_types section when using DWARF v4 debuginfo.
fdeclone-ctor-dtorC++ ObjC++ Var(flag_declone_ctor_dtor) Init(-1)Factor complex constructors and destructors to favor space over speed
fdeduce-init-listC++ ObjC++ Var(flag_deduce_init_list) Init(0)-fdeduce-init-list	enable deduction of std::initializer_list for a template type parameter from a brace-enclosed initializer-list
fdefault-double-8Fortran Var(flag_default_double)Set the default double precision kind to an 8 byte wide type
fdefault-inlineC++ ObjC++ IgnoreDoes nothing.  Preserved for backward compatibility.
fdefault-integer-8Fortran Var(flag_default_integer)Set the default integer kind to an 8 byte wide type
fdefault-real-8Fortran Var(flag_default_real)Set the default real kind to an 8 byte wide type
fdefer-popCommon Report Var(flag_defer_pop) OptimizationDefer popping functions args from stack until later
fdelayed-branchCommon Report Var(flag_delayed_branch) OptimizationAttempt to fill delay slots of branch instructions
fdelete-dead-exceptionsCommon Report Var(flag_delete_dead_exceptions) Init(0) OptimizationDelete dead instructions that may throw exceptions
fdelete-null-pointer-checksCommon Report Var(flag_delete_null_pointer_checks) Init(1) OptimizationDelete useless null pointer checks
fdevirtualizeCommon Report Var(flag_devirtualize) OptimizationTry to convert virtual calls to direct ones.
fdevirtualize-at-ltransCommon Report Var(flag_ltrans_devirtualize)Stream extra data to support more aggressive devirtualization in LTO local transformation mode
fdevirtualize-speculativelyCommon Report Var(flag_devirtualize_speculatively) OptimizationPerform speculative devirtualization
fdiagnostics-colorCommon Alias(fdiagnostics-color=,always,never)
fdiagnostics-color=Driver Common Joined RejectNegative Var(flag_diagnostics_show_color) Enum(diagnostic_color_rule) Init(DIAGNOSTICS_COLOR_NO)-fdiagnostics-color=[never|always|auto]	Colorize diagnostics
fdiagnostics-show-caretCommon Var(flag_diagnostics_show_caret) Init(1)Show the source line with a caret indicating the column
fdiagnostics-show-location=Common Joined RejectNegative Enum(diagnostic_prefixing_rule)-fdiagnostics-show-location=[once|every-line]	How often to emit source location at the beginning of line-wrapped diagnostics
fdiagnostics-show-optionCommon Var(flag_diagnostics_show_option) Init(1)Amend appropriate diagnostic messages with the command line option that controls them
fdirectives-onlyC ObjC C++ ObjC++Preprocess directives only.
fdisable-Common Joined RejectNegative Var(common_deferred_options) Defer-fdisable-[tree|rtl|ipa]-<pass>=range1+range2 disables an optimization pass
fdisable-assertionsJava
fdisable-assertions=Java JoinedOrMissing
fdollar-okFortran Var(flag_dollar_ok)Allow dollar signs in entity names
fdollars-in-identifiersC ObjC C++ ObjC++Permit '$' as an identifier character
fdseCommon Var(flag_dse) Init(1) OptimizationUse the RTL dead store elimination pass
fdump-Common Joined RejectNegative Var(common_deferred_options) Defer-fdump-<type>	Dump various compiler internals to a file
fdump-ada-specC ObjC C++ ObjC++ RejectNegative Var(flag_dump_ada_spec)Write all declarations as Ada code transitively
fdump-ada-spec-slimC ObjC C++ ObjC++ RejectNegative Var(flag_dump_ada_spec_slim)Write all declarations as Ada code for the given file only
fdump-coreFortran IgnoreDoes nothing. Preserved for backward compatibility.
fdump-final-insnsDriver RejectNegative
fdump-final-insns=Common RejectNegative Joined Var(flag_dump_final_insns)-fdump-final-insns=filename	Dump to filename the insns at the end of translation
fdump-fortran-optimizedFortran Var(flag_dump_fortran_optimized)Display the code tree after front end optimization
fdump-fortran-originalFortran Var(flag_dump_fortran_original)Display the code tree after parsing
fdump-go-spec=Common RejectNegative Joined Var(flag_dump_go_spec)-fdump-go-spec=filename	Write all declarations to file as Go code
fdump-noaddrCommon Report Var(flag_dump_noaddr)Suppress output of addresses in debugging dumps
fdump-parse-treeFortran Alias(fdump-fortran-original)Display the code tree after parsing; deprecated option
fdump-passesCommon Var(flag_dump_passes) Init(0)Dump optimization passes
fdump-unnumberedCommon Report Var(flag_dump_unnumbered)Suppress output of instruction numbers, line number notes and addresses in debugging dumps
fdump-unnumbered-linksCommon Report Var(flag_dump_unnumbered_links)Suppress output of previous and next insn numbers in debugging dumps
fdwarf2-cfi-asmCommon Report Var(flag_dwarf2_cfi_asm) Init(HAVE_GAS_CFI_DIRECTIVE)Enable CFI tables via GAS assembler directives.
fearly-inliningCommon Report Var(flag_early_inlining) Init(1) OptimizationPerform early inlining
felide-constructorsC++ ObjC++ Var(flag_elide_constructors) Init(1)
feliminate-dwarf2-dupsCommon Report Var(flag_eliminate_dwarf2_dups)Perform DWARF2 duplicate elimination
feliminate-unused-debug-symbolsCommon Report Var(flag_debug_only_used_symbols)Perform unused symbol elimination in debug info
feliminate-unused-debug-typesCommon Report Var(flag_eliminate_unused_debug_types) Init(1)Perform unused type elimination in debug info
femit-class-debug-alwaysCommon Report Var(flag_emit_class_debug_always) Init(0)Do not suppress C++ class debug information.
femit-class-fileJava Var(flag_emit_class_files)Output a class file
femit-class-filesJava Var(flag_emit_class_files)Alias for -femit-class-file
femit-struct-debug-baseonlyC ObjC C++ ObjC++-femit-struct-debug-baseonly	Aggressive reduced debug info for structs
femit-struct-debug-detailed=C ObjC C++ ObjC++ Joined-femit-struct-debug-detailed=<spec-list>	Detailed reduced debug info for structs
femit-struct-debug-reducedC ObjC C++ ObjC++-femit-struct-debug-reduced	Conservative reduced debug info for structs
fenable-Common Joined RejectNegative Var(common_deferred_options) Defer-fenable-[tree|rtl|ipa]-<pass>=range1+range2 enables an optimization pass
fenable-assertionsJava
fenable-assertions=Java JoinedOrMissing
fencoding=Java Joined RejectNegative--encoding=<encoding>	Choose input encoding (defaults from your locale)
fenforce-eh-specsC++ ObjC++ Var(flag_enforce_eh_specs) Init(1)Generate code to check exception specifications
fenum-int-equivC++ ObjC++ Ignore Warn(switch %qs is no longer supported)
fexceptionsCommon Report Var(flag_exceptions) OptimizationEnable exception handling
fexcess-precision=Common Joined RejectNegative Enum(excess_precision) Var(flag_excess_precision_cmdline) Init(EXCESS_PRECISION_DEFAULT)-fexcess-precision=[fast|standard]	Specify handling of excess floating-point precision
fexec-charset=C ObjC C++ ObjC++ Joined RejectNegative-fexec-charset=<cset>	Convert all strings and character constants to character set <cset>
fexpensive-optimizationsCommon Report Var(flag_expensive_optimizations) OptimizationPerform a number of minor, expensive optimizations
fext-numeric-literalsC++ ObjC++ Interpret imaginary, fixed-point, or other gnu number suffix as the correspondingnumber literal rather than a user-defined number literal.
fextdirs=Java Joined RejectNegative--extdirs=<path>	Set the extension directory path
fextended-identifiersC ObjC C++ ObjC++Permit universal character names (\\u and \\U) in identifiers
fextern-tls-initC++ ObjC++ Var(flag_extern_tls_init) Init(-1)Support dynamic initialization of thread-local variables in a different translation unit
fexternal-blasFortran Var(flag_external_blas)Specify that an external BLAS library should be used for matmul calls on large-size arrays
fexternal-templatesC++ ObjC++ Ignore Warn(switch %qs is no longer supported)
ff2cFortran Var(flag_f2c)Use f2c calling convention
ffast-mathCommon
ffat-lto-objectsCommon Var(flag_fat_lto_objects)Output lto objects containing both the intermediate language and binary output.
ffilelist-fileJava Var(flag_filelist_file)Input file is a file with a list of filenames to compile
ffinite-math-onlyCommon Report Var(flag_finite_math_only) Optimization SetByCombinedAssume no NaNs or infinities are generated
ffixed-Common Joined RejectNegative Var(common_deferred_options) Defer-ffixed-<register>	Mark <register> as being unavailable to the compiler
ffixed-formFortran RejectNegativeAssume that the source file is fixed form
ffixed-line-length-Fortran RejectNegative Joined UInteger Var(flag_fixed_line_length) Init(72)-ffixed-line-length-<n>	Use n as character line width in fixed mode
ffixed-line-length-noneFortran RejectNegative Var(flag_fixed_line_length,0)Allow arbitrary character line width in fixed mode
ffloat-storeCommon Report Var(flag_float_store) OptimizationDon't allocate floats and doubles in extended-precision registers
ffor-scopeC++ ObjC++ Var(flag_new_for_scope) Init(1)Scope of for-init-statement variables is local to the loop
fforce-addrCommon IgnoreDoes nothing.  Preserved for backward compatibility.
fforce-classes-archive-checkJava Var(flag_force_classes_archive_check)Always check for non gcj generated classes archives
fforward-propagateCommon Report Var(flag_forward_propagate) OptimizationPerform a forward propagation pass on RTL
ffp-contract=Common Joined RejectNegative Enum(fp_contract_mode) Var(flag_fp_contract_mode) Init(FP_CONTRACT_FAST) Optimization-ffp-contract=[off|on|fast] Perform floating-point expression contraction.
ffpe-summary=Fortran RejectNegative JoinedOrMissing-ffpe-summary=[...]	Print summary of floating point exceptions
ffpe-trap=Fortran RejectNegative JoinedOrMissing-ffpe-trap=[...]	Stop on following floating point exceptions
ffree-formFortran RejectNegativeAssume that the source file is free form
ffree-line-length-Fortran RejectNegative Joined UInteger Var(flag_free_line_length) Init(132)-ffree-line-length-<n>	Use n as character line width in free mode
ffree-line-length-noneFortran RejectNegative Var(flag_free_line_length,0)Allow arbitrary character line width in free mode
ffreestandingC ObjC C++ ObjC++Do not assume that standard C libraries and \"main\" exist
ffriend-injectionC++ ObjC++ Var(flag_friend_injection)Inject friend functions into enclosing namespace
ffrontend-optimizeFortran Var(flag_frontend_optimize) Init(-1)Enable front end optimization
ffunction-cseCommon Report Var(flag_no_function_cse,0) OptimizationAllow function addresses to be held in registers
ffunction-sectionsCommon Report Var(flag_function_sections)Place each function into its own section
fgcseCommon Report Var(flag_gcse) OptimizationPerform global common subexpression elimination
fgcse-after-reloadCommon Report Var(flag_gcse_after_reload) OptimizationPerform global common subexpression elimination after register allocationhas finished
fgcse-lasCommon Report Var(flag_gcse_las) Init(0) OptimizationPerform redundant load after store elimination in global common subexpressionelimination
fgcse-lmCommon Report Var(flag_gcse_lm) Init(1) OptimizationPerform enhanced load motion during global common subexpression elimination
fgcse-smCommon Report Var(flag_gcse_sm) Init(0) OptimizationPerform store motion after global common subexpression elimination
fgnu-keywordsC++ ObjC++ Var(flag_no_gnu_keywords, 0)Recognize GNU-defined keywords
fgnu-runtimeObjC ObjC++ LTO Report RejectNegative Var(flag_next_runtime,0) Init(NEXT_OBJC_RUNTIME)Generate code for GNU runtime environment
fgnu-tmCommon Report Var(flag_tm)Enable support for GNU transactional memory
fgnu-uniqueCommon Report Var(flag_gnu_unique) Init(1)Use STB_GNU_UNIQUE if supported by the assembler
fgnu89-inlineC ObjC Var(flag_gnu89_inline) Init(-1)Use traditional GNU semantics for inline functions
fgo-check-divide-overflowGo Var(go_check_divide_overflow) Init(1)Add explicit checks for division overflow in INT_MIN / -1
fgo-check-divide-zeroGo Var(go_check_divide_zero) Init(1)Add explicit checks for division by zero
fgo-dump-Go Joined RejectNegative-fgo-dump-<type>	Dump Go frontend internal information
fgo-optimize-Go Joined RejectNegative-fgo-optimize-<type>	Turn on optimization passes in the frontend
fgo-pkgpath=Go Joined RejectNegative-fgo-pkgpath=<string>	Set Go package path
fgo-prefix=Go Joined RejectNegative-fgo-prefix=<string>	Set package-specific prefix for exported Go names
fgo-relative-import-path=Go Joined RejectNegative-fgo-relative-import-path=<path> Treat a relative import as relative to path
fgraphiteCommon Report Var(flag_graphite) OptimizationEnable in and out of Graphite representation
fgraphite-identityCommon Report Var(flag_graphite_identity) OptimizationEnable Graphite Identity transformation
fguess-branch-probabilityCommon Report Var(flag_guess_branch_prob) OptimizationEnable guessing of branch probabilities
fguiding-declsC++ ObjC++ Ignore Warn(switch %qs is no longer supported)
fhandle-exceptionsC++ ObjC++ Optimization Alias(fexceptions) Warn({-fhandle-exceptions has been renamed -fexceptions (and is now on by default)})
fhash-synchronizationJava Var(flag_hash_synchronization)Assume the runtime uses a hash table to map an object to its synchronization structure
fhelpCommon Driver Alias(-help)
fhelp=Common Driver Joined Alias(-help=)
fhoist-adjacent-loadsCommon Report Var(flag_hoist_adjacent_loads) OptimizationEnable hoisting adjacent loads to encourage generating conditional moveinstructions
fhonor-stdC++ ObjC++ Ignore Warn(switch %qs is no longer supported)
fhostedC ObjCAssume normal C execution environment
fhuge-objectsC++ ObjC++ Ignore Warn(switch %qs is no longer supported)No longer supported
fidentCommon Report Var(flag_no_ident,0)Process #ident directives
fif-conversionCommon Report Var(flag_if_conversion) OptimizationPerform conversion of conditional jumps to branchless equivalents
fif-conversion2Common Report Var(flag_if_conversion2) OptimizationPerform conversion of conditional jumps to conditional execution
fimplement-inlinesC++ ObjC++ Var(flag_implement_inlines) Init(1)Export functions even if they can be inlined
fimplicit-inline-templatesC++ ObjC++ Var(flag_implicit_inline_templates) Init(1)Emit implicit instantiations of inline templates
fimplicit-noneFortran Var(flag_implicit_none)Specify that no implicit typing is allowed, unless overridden by explicit IMPLICIT statements
fimplicit-templatesC++ ObjC++ Var(flag_implicit_templates) Init(1)Emit implicit instantiations of templates
findirect-classesJava Var(flag_indirect_classes) Init(1)Generate instances of Class at runtime
findirect-dispatchJava Var(flag_indirect_dispatch)Use offset tables for virtual method calls
findirect-inliningCommon Report Var(flag_indirect_inlining) OptimizationPerform indirect inlining
finhibit-size-directiveCommon Report Var(flag_inhibit_size_directive)Do not generate .size directives
finit-character=Fortran RejectNegative Joined UInteger-finit-character=<n>	Initialize local character variables to ASCII value n
finit-integer=Fortran RejectNegative Joined-finit-integer=<n>	Initialize local integer variables to n
finit-local-zeroFortranInitialize local variables to zero (from g77)
finit-logical=Fortran RejectNegative Joined-finit-logical=<true|false>	Initialize local logical variables
finit-real=Fortran RejectNegative ToLower Joined Enum(gfc_init_local_real) Var(flag_init_real) Init(GFC_INIT_REAL_OFF)-finit-real=<zero|snan|nan|inf|-inf>	Initialize local real variables
finlineCommon Report Var(flag_no_inline,0) Init(0) OptimizationEnable inlining of function declared \"inline\", disabling disables all inlining
finline-atomicsCommon Report Var(flag_inline_atomics) Init(1) OptimizationInline __atomic operations when a lock free instruction sequence is available.
finline-functionsCommon Report Var(flag_inline_functions) OptimizationIntegrate functions not declared \"inline\" into their callers when profitable
finline-functionsJava
finline-functions-called-onceCommon Report Var(flag_inline_functions_called_once) OptimizationIntegrate functions only required by their single caller
finline-limit-Common RejectNegative Joined Alias(finline-limit=)
finline-limit=Common RejectNegative Joined UInteger-finline-limit=<number>	Limit the size of inlined functions to <number>
finline-small-functionsCommon Report Var(flag_inline_small_functions) OptimizationIntegrate functions into their callers when code size is known not to grow
finput-charset=C ObjC C++ ObjC++ Joined RejectNegative-finput-charset=<cset>	Specify the default character set for source files
finstrument-functionsCommon Report Var(flag_instrument_function_entry_exit)Instrument function entry and exit with profiling calls
finstrument-functions-exclude-file-list=Common RejectNegative Joined-finstrument-functions-exclude-file-list=filename,...  Do not instrument functions listed in files
finstrument-functions-exclude-function-list=Common RejectNegative Joined-finstrument-functions-exclude-function-list=name,...  Do not instrument listed functions
finteger-4-integer-8Fortran RejectNegative Var(flag_integer4_kind,8)Interpret any INTEGER(4) as an INTEGER(8)
fintrinsic-modules-pathFortran RejectNegative SeparateSpecify where to find the compiled intrinsic modules
fintrinsic-modules-path=Fortran RejectNegative JoinedSpecify where to find the compiled intrinsic modules
fipa-cpCommon Report Var(flag_ipa_cp) OptimizationPerform interprocedural constant propagation
fipa-cp-alignmentCommon Report Var(flag_ipa_cp_alignment) OptimizationPerform alignment discovery and propagation to make Interprocedural constant propagation stronger
fipa-cp-cloneCommon Report Var(flag_ipa_cp_clone) OptimizationPerform cloning to make Interprocedural constant propagation stronger
fipa-icfCommon Report Var(flag_ipa_icf) OptimizationPerform Identical Code Folding for functions and read-only variables
fipa-icf-functionsCommon Report Var(flag_ipa_icf_functions) OptimizationPerform Identical Code Folding for functions
fipa-icf-variablesCommon Report Var(flag_ipa_icf_variables)Perform Identical Code Folding for variables
fipa-matrix-reorgCommon IgnoreDoes nothing. Preserved for backward compatibility.
fipa-profileCommon Report Var(flag_ipa_profile) Init(0) OptimizationPerform interprocedural profile propagation
fipa-ptaCommon Report Var(flag_ipa_pta) Init(0) OptimizationPerform interprocedural points-to analysis
fipa-pure-constCommon Report Var(flag_ipa_pure_const) Init(0) OptimizationDiscover pure and const functions
fipa-raCommon Report Var(flag_ipa_ra) OptimizationUse caller save register across calls if possible
fipa-referenceCommon Report Var(flag_ipa_reference) Init(0) OptimizationDiscover readonly and non addressable static variables
fipa-sraCommon Report Var(flag_ipa_sra) Init(0) OptimizationPerform interprocedural reduction of aggregates
fipa-struct-reorgCommon IgnoreDoes nothing. Preserved for backward compatibility.
fira-algorithm=Common Joined RejectNegative Enum(ira_algorithm) Var(flag_ira_algorithm) Init(IRA_ALGORITHM_CB) Optimization-fira-algorithm=[CB|priority] Set the used IRA algorithm
fira-hoist-pressureCommon Report Var(flag_ira_hoist_pressure) Init(1) OptimizationUse IRA based register pressure calculationin RTL hoist optimizations.
fira-loop-pressureCommon Report Var(flag_ira_loop_pressure) OptimizationUse IRA based register pressure calculationin RTL loop optimizations.
fira-region=Common Joined RejectNegative Enum(ira_region) Var(flag_ira_region) Init(IRA_REGION_AUTODETECT) Optimization-fira-region=[one|all|mixed] Set regions for IRA
fira-share-save-slotsCommon Report Var(flag_ira_share_save_slots) Init(1) OptimizationShare slots for saving different hard registers.
fira-share-spill-slotsCommon Report Var(flag_ira_share_spill_slots) Init(1) OptimizationShare stack slots for spilled pseudo-registers.
fira-verbose=Common RejectNegative Joined UInteger Var(flag_ira_verbose) Init(5)-fira-verbose=<number>	Control IRA's level of diagnostic messages.
fisolate-erroneous-paths-attributeCommon Report Var(flag_isolate_erroneous_paths_attribute) OptimizationDetect paths that trigger erroneous or undefined behavior due a null valuebeing used in a way forbidden by a returns_nonnull or nonnullattribute.  Isolate those paths from the main control flow and turn thestatement with erroneous or undefined behavior into a trap. 
fisolate-erroneous-paths-dereferenceCommon Report Var(flag_isolate_erroneous_paths_dereference) OptimizationDetect paths that trigger erroneous or undefined behavior due todereferencing a null pointer.  Isolate those paths from the main controlflow and turn the statement with erroneous or undefined behavior into a trap.
fivar-visibility=ObjC ObjC++ Joined RejectNegative Enum(ivar_visibility) Var(default_ivar_visibility) Init(IVAR_VISIBILITY_PROTECTED)-fvisibility=[private|protected|public|package]	Set the default symbol visibility
fivoptsCommon Report Var(flag_ivopts) Init(1) OptimizationOptimize induction variables on trees
fjniJava Var(flag_jni)Assume native functions are implemented using JNI
fjump-tablesCommon Var(flag_jump_tables) Init(1) OptimizationUse jump tables for sufficiently large switch statements
fkeep-inline-dllexportC C++ ObjC ObjC++ Var(flag_keep_inline_dllexport) Init(1) Report Condition(TARGET_DLLIMPORT_DECL_ATTRIBUTES)Don't emit dllexported inline functions unless needed
fkeep-inline-functionsCommon Report Var(flag_keep_inline_functions)Generate code for functions even if they are fully inlined
fkeep-static-constsCommon Report Var(flag_keep_static_consts) Init(1)Emit static const variables even if they are not used
flabels-okC++ ObjC++ Ignore Warn(switch %qs is no longer supported)
flax-vector-conversionsC ObjC C++ ObjC++ Var(flag_lax_vector_conversions)Allow implicit conversions between vectors with differing numbers of subparts and/or differing element types.
fleading-underscoreCommon Report Var(flag_leading_underscore) Init(-1)Give external symbols a leading underscore
flifetime-dseCommon Report Var(flag_lifetime_dse) Init(1) OptimizationTell DSE that the storage for a C++ object is dead when the constructorstarts and when the destructor finishes.
flive-range-shrinkageCommon Report Var(flag_live_range_shrinkage) Init(0) OptimizationRelief of register pressure through live range shrinkage
flocal-ivarsObjC ObjC++ Var(flag_local_ivars) Init(1)Allow access to instance variables as if they were local declarations within instance method implementations.
floop-blockCommon Report Var(flag_loop_block) OptimizationEnable Loop Blocking transformation
floop-flattenCommon IgnoreDoes nothing. Preserved for backward compatibility.
floop-interchangeCommon Report Var(flag_loop_interchange) OptimizationEnable Loop Interchange transformation
floop-nest-optimizeCommon Report Var(flag_loop_optimize_isl) OptimizationEnable the ISL based loop nest optimizer
floop-optimizeCommon IgnoreDoes nothing.  Preserved for backward compatibility.
floop-parallelize-allCommon Report Var(flag_loop_parallelize_all) OptimizationMark all loops as parallel
floop-strip-mineCommon Report Var(flag_loop_strip_mine) OptimizationEnable Loop Strip Mining transformation
floop-unroll-and-jamCommon Report Var(flag_loop_unroll_jam) OptimizationEnable Loop Unroll Jam transformation
flra-rematCommon Report Var(flag_lra_remat) OptimizationDo CFG-sensitive rematerialization in LRA
fltoCommonEnable link-time optimization.
flto-compression-level=Common Joined RejectNegative UInteger Var(flag_lto_compression_level) Init(-1)-flto-compression-level=<number>	Use zlib compression level <number> for IL
flto-odr-type-mergingCommon Report Var(flag_lto_odr_type_mering) Init(1)Merge C++ types using One Definition Rule
flto-partition=Common Joined RejectNegative Enum(lto_partition_model) Var(flag_lto_partition) Init(LTO_PARTITION_BALANCED)Specify the algorithm to partition symbols and vars at linktime
flto-reportCommon Report Var(flag_lto_report) Init(0)Report various link-time optimization statistics
flto-report-wpaCommon Report Var(flag_lto_report_wpa) Init(0)Report various link-time optimization statistics for WPA only
flto=Common RejectNegative Joined Var(flag_lto)Link-time optimization with number of parallel jobs or jobserver.
fltransLTO Report Var(flag_ltrans)Run the link-time optimizer in local transformation (LTRANS) mode.
fltrans-output-list=LTO Joined Var(ltrans_output_list)Specify a file to which a list of files output by LTRANS is written.
fmain=Driver JoinedOrMissing RejectNegative
fmath-errnoCommon Report Var(flag_errno_math) Init(1) Optimization SetByCombinedSet errno after built-in math functions
fmax-array-constructor=Fortran RejectNegative Joined UInteger Var(flag_max_array_constructor) Init(65535)-fmax-array-constructor=<n>	Maximum number of objects in an array constructor
fmax-errors=Common Joined RejectNegative UInteger Var(flag_max_errors)-fmax-errors=<number>	Maximum number of errors to report
fmax-identifier-length=Fortran RejectNegative Joined UInteger-fmax-identifier-length=<n>	Maximum identifier length
fmax-stack-var-size=Fortran RejectNegative Joined UInteger Var(flag_max_stack_var_size) Init(-2)-fmax-stack-var-size=<n>	Size in bytes of the largest array that will be put on the stack
fmax-subrecord-length=Fortran RejectNegative Joined UInteger Var(flag_max_subrecord_length)-fmax-subrecord-length=<n>	Maximum length for subrecords
fmem-reportCommon Report Var(mem_report)Report on permanent memory allocation
fmem-report-wpaCommon Report Var(mem_report_wpa)Report on permanent memory allocation in WPA only
fmerge-all-constantsCommon Report Var(flag_merge_constants,2) Init(1)Attempt to merge identical constants and constant variables
fmerge-constantsCommon Report Var(flag_merge_constants,1)Attempt to merge identical constants across compilation units
fmerge-debug-stringsCommon Report Var(flag_merge_debug_strings) Init(1)Attempt to merge identical debug strings across compilation units
fmessage-length=Common RejectNegative Joined UInteger-fmessage-length=<number>	Limit diagnostics to <number> characters per line.  0 suppresses line-wrapping
fmodule-privateFortran Var(flag_module_private)Set default accessibility of module entities to PRIVATE.
fmodulo-schedCommon Report Var(flag_modulo_sched) OptimizationPerform SMS based modulo scheduling before the first scheduling pass
fmodulo-sched-allow-regmovesCommon Report Var(flag_modulo_sched_allow_regmoves) OptimizationPerform SMS based modulo scheduling with register moves allowed
fmove-loop-invariantsCommon Report Var(flag_move_loop_invariants) OptimizationMove loop invariant computations out of loops
fms-extensionsC ObjC C++ ObjC++ Var(flag_ms_extensions)Don't warn about uses of Microsoft extensions
fmudflapC ObjC C++ ObjC++ Ignore Warn(switch %qs is no longer supported)
fmudflapirC ObjC C++ ObjC++ Ignore Warn(switch %qs is no longer supported)
fmudflapthC ObjC C++ ObjC++ Ignore Warn(switch %qs is no longer supported)
fname-mangling-version-C++ ObjC++ Joined Ignore Warn(switch %qs is no longer supported)
fnew-abiC++ ObjC++ Ignore Warn(switch %qs is no longer supported)
fnext-runtimeObjC ObjC++ LTO Report RejectNegative Var(flag_next_runtime)Generate code for NeXT (Apple Mac OS X) runtime environment
fnil-receiversObjC ObjC++ Var(flag_nil_receivers) Init(1)Assume that receivers of Objective-C messages may be nil
fno-vect-cost-modelCommon RejectNegative Alias(fvect-cost-model=,unlimited)Enables the unlimited vectorizer cost model.  Preserved for backward compatibility.
fnon-call-exceptionsCommon Report Var(flag_non_call_exceptions) OptimizationSupport synchronous non-call exceptions
fnonansi-builtinsC++ ObjC++ Var(flag_no_nonansi_builtin, 0)
fnonnull-objectsC++ ObjC++ Ignore Warn(switch %qs is no longer supported)
fnothrow-optC++ ObjC++ Optimization Var(flag_nothrow_opt)Treat a throw() exception specification as noexcept to improve code size
fobjc-abi-version=ObjC ObjC++ LTO Joined Report RejectNegative UInteger Var(flag_objc_abi)Specify which ABI to use for Objective-C family code and meta-data generation.
fobjc-call-cxx-cdtorsObjC++ Var(flag_objc_call_cxx_cdtors)Generate special Objective-C methods to initialize/destroy non-POD C++ ivars, if needed
fobjc-direct-dispatchObjC ObjC++ Var(flag_objc_direct_dispatch)Allow fast jumps to the message dispatcher
fobjc-exceptionsObjC ObjC++ Var(flag_objc_exceptions)Enable Objective-C exception and synchronization syntax
fobjc-gcObjC ObjC++ LTO Var(flag_objc_gc)Enable garbage collection (GC) in Objective-C/Objective-C++ programs
fobjc-nilcheckObjC ObjC++ Var(flag_objc_nilcheck,1)Enable inline checks for nil receivers with the NeXT runtime and ABI version 2.
fobjc-sjlj-exceptionsObjC ObjC++ Var(flag_objc_sjlj_exceptions) Init(-1)Enable Objective-C setjmp exception handling runtime
fobjc-std=objc1ObjC ObjC++ Var(flag_objc1_only)Conform to the Objective-C 1.0 language as implemented in GCC 4.0
foffload-abi=Common Joined RejectNegative Enum(offload_abi) Var(flag_offload_abi) Init(OFFLOAD_ABI_UNSET)-foffload-abi=[lp64|ilp32]     Set the ABI to use in an offload compiler
foffload=Common Driver Joined MissingArgError(options or targets missing after %qs)-foffload=<targets>=<options>  Specify offloading targets and options for them
fomit-frame-pointerCommon Report Var(flag_omit_frame_pointer) OptimizationWhen possible do not generate stack frames
fopenaccC ObjC C++ ObjC++ LTO Var(flag_openacc)Enable OpenACC
fopenaccFortran LTO
fopenmpC ObjC C++ ObjC++ LTO Var(flag_openmp)Enable OpenMP (implies -frecursive in Fortran)
fopenmpFortran LTO
fopenmp-simdC ObjC C++ ObjC++ Var(flag_openmp_simd)Enable OpenMP's SIMD directives
fopenmp-simdFortran
foperator-namesC++ ObjC++Recognize C++ keywords like \"compl\" and \"xor\"
fopt-infoCommon Report Var(flag_opt_info) OptimizationEnable all optimization info dumps on stderr
fopt-info-Common Joined RejectNegative Var(common_deferred_options) Defer-fopt-info[-<type>=filename]	Dump compiler optimization details
foptimize-register-moveCommon IgnoreDoes nothing. Preserved for backward compatibility.
foptimize-sibling-callsCommon Report Var(flag_optimize_sibling_calls) OptimizationOptimize sibling and tail recursive calls
foptimize-static-class-initializationJava Var(flag_optimize_sci)Enable optimization of static class initialization code
foptimize-strlenCommon Report Var(flag_optimize_strlen) OptimizationEnable string length optimizations on trees
foptional-diagsC++ ObjC++ IgnoreDoes nothing.  Preserved for backward compatibility.
foutput-class-dir=Java Joined RejectNegative
fpack-derivedFortran Var(flag_pack_derived)Try to lay out derived types as compactly as possible
fpack-structCommon Report Var(flag_pack_struct) OptimizationPack structure members together without holes
fpack-struct=Common RejectNegative Joined UInteger Optimization-fpack-struct=<number>	Set initial maximum structure member alignment
fpartial-inliningCommon Report Var(flag_partial_inlining) OptimizationPerform partial inlining
fpcc-struct-returnCommon Report Var(flag_pcc_struct_return,1) Init(DEFAULT_PCC_STRUCT_RETURN)Return small aggregates in memory, not registers
fpch-depsC ObjC C++ ObjC++
fpch-preprocessC ObjC C++ ObjC++Look for and use PCH files even when preprocessing
fpeel-loopsCommon Report Var(flag_peel_loops) OptimizationPerform loop peeling
fpeepholeCommon Report Var(flag_no_peephole,0) OptimizationEnable machine specific peephole optimizations
fpeephole2Common Report Var(flag_peephole2) OptimizationEnable an RTL peephole pass before sched2
fpermissiveC++ ObjC++ Var(flag_permissive)Downgrade conformance errors to warnings
fpicCommon Report Var(flag_pic,1) Negative(fpie)Generate position-independent code if possible (small mode)
fpieCommon Report Var(flag_pie,1) Negative(fPIC)Generate position-independent code for executables if possible (small mode)
fplan9-extensionsC ObjC Var(flag_plan9_extensions)Enable Plan 9 language extensions
fplugin-arg-Common Joined RejectNegative Var(common_deferred_options) Defer-fplugin-arg-<name>-<key>[=<value>]	Specify argument <key>=<value> for plugin <name>
fplugin=Common Joined RejectNegative Var(common_deferred_options) DeferSpecify a plugin to load
fpost-ipa-mem-reportCommon Report Var(post_ipa_mem_report)Report on memory allocation before interprocedural optimization
fpre-ipa-mem-reportCommon Report Var(pre_ipa_mem_report)Report on memory allocation before interprocedural optimization
fpredictive-commoningCommon Report Var(flag_predictive_commoning) OptimizationRun predictive commoning optimization.
fprefetch-loop-arraysCommon Report Var(flag_prefetch_loop_arrays) Init(-1) OptimizationGenerate prefetch instructions, if available, for arrays in loops
fpreprocessedC ObjC C++ ObjC++Treat the input file as already preprocessed
fpreprocessedFortran
fpretty-templatesC++ ObjC++ Var(flag_pretty_templates) Init(1)-fno-pretty-templates Do not pretty-print template specializations as the template signature followed by the arguments
fprofileCommon Report Var(profile_flag)Enable basic program profiling code
fprofile-arcsCommon Report Var(profile_arc_flag)Insert arc-based program profiling code
fprofile-correctionCommon Report Var(flag_profile_correction)Enable correction of flow inconsistent profile data input
fprofile-dir=Common Joined RejectNegative Var(profile_data_prefix)Set the top-level directory for storing the profile data.The default is 'pwd'.
fprofile-generateCommonEnable common options for generating profile info for profile feedback directed optimizations
fprofile-generate=Common Joined RejectNegativeEnable common options for generating profile info for profile feedback directed optimizations, and set -fprofile-dir=
fprofile-reorder-functionsCommon Report Var(flag_profile_reorder_functions)Enable function reordering that improves code placement
fprofile-reportCommon Report Var(profile_report)Report on consistency of profile
fprofile-useCommon Var(flag_profile_use)Enable common options for performing profile feedback directed optimizations
fprofile-use=Common Joined RejectNegativeEnable common options for performing profile feedback directed optimizations, and set -fprofile-dir=
fprofile-valuesCommon Report Var(flag_profile_values)Insert code to profile values of expressions
fprotect-parensFortran Var(flag_protect_parens) Init(-1)Protect parentheses in expressions
frandom-seedCommon Var(common_deferred_options) Defer
frandom-seed=Common Joined RejectNegative Var(common_deferred_options) Defer-frandom-seed=<number>	Make compile reproducible using <number>
frange-checkFortran Var(flag_range_check) Init(1)Enable range checking during compilation
freal-4-real-10Fortran RejectNegative Var(flag_real4_kind,10)Interpret any REAL(4) as a REAL(10)
freal-4-real-16Fortran RejectNegative Var(flag_real4_kind,16)Interpret any REAL(4) as a REAL(16)
freal-4-real-8Fortran RejectNegative Var(flag_real4_kind,8)Interpret any REAL(4) as a REAL(8)
freal-8-real-10Fortran RejectNegative Var(flag_real8_kind,10)Interpret any REAL(8) as a REAL(10)
freal-8-real-16Fortran RejectNegative Var(flag_real8_kind,16)Interpret any REAL(8) as a REAL(16)
freal-8-real-4Fortran RejectNegative Var(flag_real8_kind,4)Interpret any REAL(8) as a REAL(4)
frealloc-lhsFortran Var(flag_realloc_lhs) Init(-1)Reallocate the LHS in assignments
freciprocal-mathCommon Report Var(flag_reciprocal_math) SetByCombined OptimizationSame as -fassociative-math for expressions which include division.
frecord-gcc-switchesCommon Report Var(flag_record_gcc_switches)Record gcc command line switches in the object file.
frecord-marker=4Fortran RejectNegative Var(flag_record_marker,4)Use a 4-byte record marker for unformatted files
frecord-marker=8Fortran RejectNegative Var(flag_record_marker,8)Use an 8-byte record marker for unformatted files
frecursiveFortran Var(flag_recursive)Allocate local variables on the stack to allow indirect recursion
freduced-reflectionJava Var(flag_reduced_reflection)Reduce the amount of reflection meta-data generated
freeCommon Report Var(flag_ree) Init(0)Turn on Redundant Extensions Elimination pass.
freg-struct-returnCommon Report Var(flag_pcc_struct_return,0) OptimizationReturn small aggregates in registers
fregmoveCommon IgnoreDoes nothing. Preserved for backward compatibility.
frename-registersCommon Report Var(flag_rename_registers) Init(2) OptimizationPerform a register renaming optimization pass
freorder-blocksCommon Report Var(flag_reorder_blocks) OptimizationReorder basic blocks to improve code placement
freorder-blocks-and-partitionCommon Report Var(flag_reorder_blocks_and_partition) OptimizationReorder basic blocks and partition into hot and cold sections
freorder-functionsCommon Report Var(flag_reorder_functions) OptimizationReorder functions to improve code placement
frepack-arraysFortran Var(flag_repack_arrays)Copy array sections into a contiguous block on procedure entry
freplace-objc-classesObjC ObjC++ LTO Var(flag_replace_objc_classes)Used in Fix-and-Continue mode to indicate that object files may be swapped in at runtime
frepoC++ ObjC++Enable automatic template instantiation
freport-bugCommon Driver Var(flag_report_bug)Collect and dump debug information into temporary file if ICE in C/C++compiler occured.
frequire-return-statementGo Var(go_require_return_statement) Init(1) WarningFunctions which return values must end with return statements
frerun-cse-after-loopCommon Report Var(flag_rerun_cse_after_loop) OptimizationAdd a common subexpression elimination pass after loop optimizations
frerun-loop-optCommon IgnoreDoes nothing.  Preserved for backward compatibility.
freschedule-modulo-scheduled-loopsCommon Report Var(flag_resched_modulo_sched) OptimizationEnable/Disable the traditional scheduling in loops that already passed modulo scheduling
fresolution=LTO JoinedThe resolution file
frounding-mathCommon Report Var(flag_rounding_math) Optimization SetByCombinedDisable optimizations that assume default FP rounding behavior
frttiC++ ObjC++ Optimization Var(flag_rtti) Init(1)Generate run time type descriptor information
fsanitize-recoverCommon ReportThis switch is deprecated; use -fsanitize-recover= instead
fsanitize-recover=Common Report JoinedAfter diagnosing undefined behavior attempt to continue execution
fsanitize-undefined-trap-on-errorCommon Report Var(flag_sanitize_undefined_trap_on_error) Init(0)Use trap instead of a library function for undefined behavior sanitization
fsanitize=Common Driver Report JoinedSelect what to sanitize
fsaw-java-fileJava Undocumented RejectNegative
fsched-critical-path-heuristicCommon Report Var(flag_sched_critical_path_heuristic) Init(1) OptimizationEnable the critical path heuristic in the scheduler
fsched-dep-count-heuristicCommon Report Var(flag_sched_dep_count_heuristic) Init(1) OptimizationEnable the dependent count heuristic in the scheduler
fsched-group-heuristicCommon Report Var(flag_sched_group_heuristic) Init(1) OptimizationEnable the group heuristic in the scheduler
fsched-interblockCommon Report Var(flag_schedule_interblock) Init(1) OptimizationEnable scheduling across basic blocks
fsched-last-insn-heuristicCommon Report Var(flag_sched_last_insn_heuristic) Init(1) OptimizationEnable the last instruction heuristic in the scheduler
fsched-pressureCommon Report Var(flag_sched_pressure) Init(0) OptimizationEnable register pressure sensitive insn scheduling
fsched-rank-heuristicCommon Report Var(flag_sched_rank_heuristic) Init(1) OptimizationEnable the rank heuristic in the scheduler
fsched-specCommon Report Var(flag_schedule_speculative) Init(1) OptimizationAllow speculative motion of non-loads
fsched-spec-insn-heuristicCommon Report Var(flag_sched_spec_insn_heuristic) Init(1) OptimizationEnable the speculative instruction heuristic in the scheduler
fsched-spec-loadCommon Report Var(flag_schedule_speculative_load) OptimizationAllow speculative motion of some loads
fsched-spec-load-dangerousCommon Report Var(flag_schedule_speculative_load_dangerous) OptimizationAllow speculative motion of more loads
fsched-stalled-insnsCommon Report Var(flag_sched_stalled_insns) Optimization UIntegerAllow premature scheduling of queued insns
fsched-stalled-insns-depCommon Report Var(flag_sched_stalled_insns_dep,1) Init(1) Optimization UIntegerSet dependence distance checking in premature scheduling of queued insns
fsched-stalled-insns-dep=Common RejectNegative Joined UInteger Optimization-fsched-stalled-insns-dep=<number>	Set dependence distance checking in premature scheduling of queued insns
fsched-stalled-insns=Common RejectNegative Joined UInteger Optimization-fsched-stalled-insns=<number>	Set number of queued insns that can be prematurely scheduled
fsched-verbose=Common RejectNegative Joined UInteger Var(sched_verbose_param)-fsched-verbose=<number>	Set the verbosity level of the scheduler
fsched2-use-superblocksCommon Report Var(flag_sched2_use_superblocks) OptimizationIf scheduling post reload, do superblock scheduling
fsched2-use-tracesCommon IgnoreDoes nothing.  Preserved for backward compatibility.
fschedule-fusionCommon Report Var(flag_schedule_fusion) Init(2) OptimizationPerform a target dependent instruction fusion optimization pass
fschedule-insnsCommon Report Var(flag_schedule_insns) OptimizationReschedule instructions before register allocation
fschedule-insns2Common Report Var(flag_schedule_insns_after_reload) OptimizationReschedule instructions after register allocation
fsecond-underscoreFortran Var(flag_second_underscore) Init(-1)Append a second underscore if the name already contains an underscore
fsection-anchorsCommon Report Var(flag_section_anchors) OptimizationAccess data in the same section from shared anchor points
fseeCommon IgnoreDoes nothing.  Preserved for backward compatibility.
fsel-sched-pipeliningCommon Report Var(flag_sel_sched_pipelining) Init(0) OptimizationPerform software pipelining of inner loops during selective scheduling
fsel-sched-pipelining-outer-loopsCommon Report Var(flag_sel_sched_pipelining_outer_loops) Init(0) OptimizationPerform software pipelining of outer loops during selective scheduling
fsel-sched-reschedule-pipelinedCommon Report Var(flag_sel_sched_reschedule_pipelined) Init(0) OptimizationReschedule pipelined regions without pipelining
fselective-schedulingCommon Report Var(flag_selective_scheduling) OptimizationSchedule instructions using selective scheduling algorithm
fselective-scheduling2Common Report Var(flag_selective_scheduling2) Optimization Run selective scheduling after reload
fsemantic-interpositionCommon Report Var(flag_semantic_interposition) Init(1)Allow interposing function (or variables) by ones with different semantics (or initializer) respectively by dynamic linker
fshort-doubleC ObjC C++ ObjC++ LTO Optimization Var(flag_short_double)Use the same size for double as for float
fshort-enumsAda AdaWhy AdaSCILUse the narrowest integer type possible for enumeration types
fshort-enumsC ObjC C++ ObjC++ LTO Optimization Var(flag_short_enums)Use the narrowest integer type possible for enumeration types
fshort-enumsFortran Var(flag_short_enums)
fshort-wcharC ObjC C++ ObjC++ LTO Optimization Var(flag_short_wchar)Force the underlying type for \"wchar_t\" to be \"unsigned short\"
fshow-columnCommon Report Var(flag_show_column) Init(1)Show column numbers in diagnostics, when available.  Default on
fshrink-wrapCommon Report Var(flag_shrink_wrap) OptimizationEmit function prologues only before parts of the function that need it,rather than at the top of the function.
fsign-zeroFortran Var(flag_sign_zero) Init(1)Apply negative sign to zero values
fsignaling-nansCommon Report Var(flag_signaling_nans) Optimization SetByCombinedDisable optimizations observable by IEEE signaling NaNs
fsigned-bitfieldsC ObjC C++ ObjC++ Var(flag_signed_bitfields) Init(1)When \"signed\" or \"unsigned\" is not given make the bitfield signed
fsigned-charC ObjC C++ ObjC++ LTO Var(flag_signed_char)Make \"char\" signed by default
fsigned-zerosCommon Report Var(flag_signed_zeros) Init(1) Optimization SetByCombinedDisable floating point optimizations that ignore the IEEE signedness of zero
fsimd-cost-model=Common Joined RejectNegative Enum(vect_cost_model) Var(flag_simd_cost_model) Init(VECT_COST_MODEL_UNLIMITED) OptimizationSpecifies the vectorization cost model for code marked with a simd directive
fsingle-precision-constantCommon Report Var(flag_single_precision_constant) OptimizationConvert floating point constants to single precision constants
fsized-deallocationC++ ObjC++ Var(flag_sized_deallocation) Init(-1)Enable C++14 sized deallocation support
fsource-filename=Java Joined Undocumented 
fsource=Java JoinedSet the source language version
fsplit-ivs-in-unrollerCommon Report Var(flag_split_ivs_in_unroller) Init(1) OptimizationSplit lifetimes of induction variables when loops are unrolled
fsplit-stackCommon Report Var(flag_split_stack) Init(-1)Generate discontiguous stack frames
fsplit-wide-typesCommon Report Var(flag_split_wide_types) OptimizationSplit wide types into independent registers
fsquangleC++ ObjC++ Ignore Warn(switch %qs is no longer supported)
fssa-phioptCommon Report Var(flag_ssa_phiopt) OptimizationOptimize conditional patterns using SSA PHI nodes
fstack-arraysFortran Var(flag_stack_arrays) Init(-1)Put all local arrays on stack.
fstack-checkCommon Alias(fstack-check=, specific, no)Insert stack checking code into the program.  Same as -fstack-check=specific
fstack-check=Common Report RejectNegative Joined-fstack-check=[no|generic|specific]	Insert stack checking code into the program
fstack-limitCommon Var(common_deferred_options) Defer
fstack-limit-register=Common RejectNegative Joined Var(common_deferred_options) Defer-fstack-limit-register=<register>	Trap if the stack goes past <register>
fstack-limit-symbol=Common RejectNegative Joined Var(common_deferred_options) Defer-fstack-limit-symbol=<name>	Trap if the stack goes past symbol <name>
fstack-protectorCommon Report Var(flag_stack_protect, 1)Use propolice as a stack protection method
fstack-protector-allCommon Report RejectNegative Var(flag_stack_protect, 2)Use a stack protection method for every function
fstack-protector-explicitCommon Report RejectNegative Var(flag_stack_protect, 4)Use stack protection method only for functions with the stack_protect attribute
fstack-protector-strongCommon Report RejectNegative Var(flag_stack_protect, 3)Use a smart stack protection method for certain functions
fstack-reuse=Common Joined RejectNegative Enum(stack_reuse_level) Var(flag_stack_reuse) Init(SR_ALL) Optimization-fstack-reuse=[all|named_vars|none] Set stack reuse level for local variables.
fstack-usageCommon RejectNegative Var(flag_stack_usage)Output stack usage information on a per-function basis
fstatsC++ ObjC++ Var(flag_detailed_statistics)Display statistics accumulated during compilation
fstdarg-optCommon Report Var(flag_stdarg_opt) Init(1) OptimizationOptimize amount of stdarg registers saved to stack at start of function
fstore-checkJava Var(flag_store_check) Init(1)Enable assignability checks for stores into object arrays
fstrength-reduceCommon IgnoreDoes nothing.  Preserved for backward compatibility.
fstrict-aliasingCommon Report Var(flag_strict_aliasing) OptimizationAssume strict aliasing rules apply
fstrict-enumsC++ ObjC++ Optimization Var(flag_strict_enums)Assume that values of enumeration type are always within the minimum range of that type
fstrict-overflowCommon Report Var(flag_strict_overflow) OptimizationTreat signed overflow as undefined
fstrict-prototypeC++ ObjC++ Ignore Warn(switch %qs is no longer supported)
fstrict-volatile-bitfieldsCommon Report Var(flag_strict_volatile_bitfields) Init(-1) OptimizationForce bitfield accesses to match their type width
fsync-libcallsCommon Report Var(flag_sync_libcalls) Init(1)Implement __atomic operations via libcalls to legacy __sync functions
fsyntax-onlyCommon Report Var(flag_syntax_only)Check for syntax errors, then stop
ftabstop=C ObjC C++ ObjC++ Joined RejectNegative UInteger-ftabstop=<number>	Distance between tab stops for column reporting
ftarget-helpCommon Driver Alias(-target-help)
ftarget=Java JoinedSet the target VM version
ftemplate-backtrace-limit=C++ ObjC++ Joined RejectNegative UInteger Var(template_backtrace_limit) Init(10)Set the maximum number of template instantiation notes for a single warning or error
ftemplate-depth-C++ ObjC++ Joined RejectNegative Undocumented Alias(ftemplate-depth=)
ftemplate-depth=C++ ObjC++ Joined RejectNegative UInteger-ftemplate-depth=<number>	Specify maximum template instantiation depth
ftest-coverageCommon Report Var(flag_test_coverage)Create data files needed by \"gcov\"
fthis-is-variableC++ ObjC++ Ignore Warn(switch %qs is no longer supported)
fthread-jumpsCommon Report Var(flag_thread_jumps) OptimizationPerform jump threading optimizations
fthreadsafe-staticsC++ ObjC++ Optimization Var(flag_threadsafe_statics) Init(1)-fno-threadsafe-statics	Do not generate thread-safe code for initializing local statics
ftime-reportCommon Report Var(time_report)Report the time taken by each compiler pass
ftls-model=Common Joined RejectNegative Enum(tls_model) Var(flag_tls_default) Init(TLS_MODEL_GLOBAL_DYNAMIC)-ftls-model=[global-dynamic|local-dynamic|initial-exec|local-exec]	Set the default thread-local storage code generation model
ftoplevel-reorderCommon Report Var(flag_toplevel_reorder) Init(2)Reorder top level functions, variables, and asms
ftracerCommon Report Var(flag_tracer) OptimizationPerform superblock formation via tail duplication
ftrack-macro-expansionC ObjC C++ ObjC++ JoinedOrMissing RejectNegative UInteger
ftrack-macro-expansion=C ObjC C++ ObjC++ JoinedOrMissing RejectNegative UInteger-ftrack-macro-expansion=<0|1|2>  Track locations of tokens coming from macro expansion and display them in error messages
ftrapping-mathCommon Report Var(flag_trapping_math) Init(1) Optimization SetByCombinedAssume floating-point operations can trap
ftrapvCommon Report Var(flag_trapv) OptimizationTrap for signed overflow in addition, subtraction and multiplication
ftree-bit-ccpCommon Report Var(flag_tree_bit_ccp) OptimizationEnable SSA-BIT-CCP optimization on trees
ftree-builtin-call-dceCommon Report Var(flag_tree_builtin_call_dce) Init(0) OptimizationEnable conditional dead code elimination for builtin calls
ftree-ccpCommon Report Var(flag_tree_ccp) OptimizationEnable SSA-CCP optimization on trees
ftree-chCommon Report Var(flag_tree_ch) OptimizationEnable loop header copying on trees
ftree-coalesce-inlined-varsCommon Report Var(flag_ssa_coalesce_vars,1) Init(2) RejectNegative OptimizationEnable coalescing of copy-related user variables that are inlined
ftree-coalesce-varsCommon Report Var(flag_ssa_coalesce_vars,2) OptimizationEnable coalescing of all copy-related user variables
ftree-copy-propCommon Report Var(flag_tree_copy_prop) OptimizationEnable copy propagation on trees
ftree-copyrenameCommon Report Var(flag_tree_copyrename) OptimizationReplace SSA temporaries with better names in copies
ftree-cselimCommon Report Var(flag_tree_cselim) Init(2) OptimizationTransform condition stores into unconditional ones
ftree-dceCommon Report Var(flag_tree_dce) OptimizationEnable SSA dead code elimination optimization on trees
ftree-dominator-optsCommon Report Var(flag_tree_dom) OptimizationEnable dominator optimizations
ftree-dseCommon Report Var(flag_tree_dse) OptimizationEnable dead store elimination
ftree-forwpropCommon Report Var(flag_tree_forwprop) Init(1) OptimizationEnable forward propagation on trees
ftree-freCommon Report Var(flag_tree_fre) OptimizationEnable Full Redundancy Elimination (FRE) on trees
ftree-loop-distribute-patternsCommon Report Var(flag_tree_loop_distribute_patterns) OptimizationEnable loop distribution for patterns transformed into a library call
ftree-loop-distributionCommon Report Var(flag_tree_loop_distribution) OptimizationEnable loop distribution on trees
ftree-loop-if-convertCommon Report Var(flag_tree_loop_if_convert) Init(-1) OptimizationConvert conditional jumps in innermost loops to branchless equivalents
ftree-loop-if-convert-storesCommon Report Var(flag_tree_loop_if_convert_stores) OptimizationAlso if-convert conditional jumps containing memory writes
ftree-loop-imCommon Report Var(flag_tree_loop_im) Init(1) OptimizationEnable loop invariant motion on trees
ftree-loop-ivcanonCommon Report Var(flag_tree_loop_ivcanon) Init(1) OptimizationCreate canonical induction variables in loops
ftree-loop-linearCommon Alias(floop-interchange)Enable loop interchange transforms.  Same as -floop-interchange
ftree-loop-optimizeCommon Report Var(flag_tree_loop_optimize) Init(1) OptimizationEnable loop optimizations on tree level
ftree-loop-vectorizeCommon Report Var(flag_tree_loop_vectorize) OptimizationEnable loop vectorization on trees
ftree-lrsCommon Report Var(flag_tree_live_range_split) OptimizationPerform live range splitting during the SSA->normal pass
ftree-parallelize-loops=Common Report Joined RejectNegative UInteger Var(flag_tree_parallelize_loops) Init(1) OptimizationEnable automatic parallelization of loops
ftree-partial-preCommon Report Var(flag_tree_partial_pre) OptimizationIn SSA-PRE optimization on trees, enable partial-partial redundancy elimination
ftree-phipropCommon Report Var(flag_tree_phiprop) Init(1) OptimizationEnable hoisting loads from conditional pointers.
ftree-preCommon Report Var(flag_tree_pre) OptimizationEnable SSA-PRE optimization on trees
ftree-ptaCommon Report Var(flag_tree_pta) OptimizationPerform function-local points-to analysis on trees.
ftree-reassocCommon Report Var(flag_tree_reassoc) Init(1) OptimizationEnable reassociation on tree level
ftree-saliasCommon IgnoreDoes nothing.  Preserved for backward compatibility.
ftree-scev-cpropCommon Report Var(flag_tree_scev_cprop) Init(1) OptimizationEnable copy propagation of scalar-evolution information.
ftree-sinkCommon Report Var(flag_tree_sink) OptimizationEnable SSA code sinking on trees
ftree-slp-vectorizeCommon Report Var(flag_tree_slp_vectorize) OptimizationEnable basic block vectorization (SLP) on trees
ftree-slsrCommon Report Var(flag_tree_slsr) OptimizationPerform straight-line strength reduction
ftree-sraCommon Report Var(flag_tree_sra) OptimizationPerform scalar replacement of aggregates
ftree-store-ccpCommon IgnoreDoes nothing.  Preserved for backward compatibility.
ftree-store-copy-propCommon IgnoreDoes nothing.  Preserved for backward compatibility.
ftree-switch-conversionCommon Report Var(flag_tree_switch_conversion) OptimizationPerform conversions of switch initializations.
ftree-tail-mergeCommon Report Var(flag_tree_tail_merge) OptimizationEnable tail merging on trees
ftree-terCommon Report Var(flag_tree_ter) OptimizationReplace temporary expressions in the SSA->normal pass
ftree-vect-loop-versionCommon IgnoreDoes nothing. Preserved for backward compatibility.
ftree-vectorizeCommon Report Var(flag_tree_vectorize) OptimizationEnable vectorization on trees
ftree-vectorizer-verbose=Common Joined RejectNegative IgnoreDoes nothing.  Preserved for backward compatibility.
ftree-vrpCommon Report Var(flag_tree_vrp) Init(0) OptimizationPerform Value Range Propagation on trees
funderscoringFortran Var(flag_underscoring) Init(1)Append underscores to externally visible names
funit-at-a-timeCommon Report Var(flag_unit_at_a_time) Init(1)Compile whole compilation unit at a time
funroll-all-loopsCommon Report Var(flag_unroll_all_loops) OptimizationPerform loop unrolling for all loops
funroll-loopsCommon Report Var(flag_unroll_loops) OptimizationPerform loop unrolling when iteration count is known
funsafe-loop-optimizationsCommon Report Var(flag_unsafe_loop_optimizations) OptimizationAllow loop optimizations to assume that the loops behave in normal way
funsafe-math-optimizationsCommon Report Var(flag_unsafe_math_optimizations) Optimization SetByCombinedAllow math optimizations that may violate IEEE or ISO standards
funsigned-bitfieldsC ObjC C++ ObjC++ Var(flag_signed_bitfields, 0)When \"signed\" or \"unsigned\" is not given make the bitfield unsigned
funsigned-charC ObjC C++ ObjC++ LTO Var(flag_signed_char, 0)Make \"char\" unsigned by default
funswitch-loopsCommon Report Var(flag_unswitch_loops) OptimizationPerform loop unswitching
funwind-tablesCommon Report Var(flag_unwind_tables) OptimizationJust generate unwind tables for exception handling
fuse-atomic-builtinsJava Var(flag_use_atomic_builtins) Init(0)Generate code for built-in atomic operations
fuse-boehm-gcJava Var(flag_use_boehm_gc)Generate code for the Boehm GC
fuse-cxa-atexitC++ ObjC++ Var(flag_use_cxa_atexit) Init(DEFAULT_USE_CXA_ATEXIT)Use __cxa_atexit to register destructors
fuse-cxa-get-exception-ptrC++ ObjC++ Var(flag_use_cxa_get_exception_ptr) Init(2)Use __cxa_get_exception_ptr in exception handling
fuse-divide-subroutineJava Var(flag_use_divide_subroutine) Init(1)Call a library routine to do integer divisions
fuse-ld=bfdCommon Driver Negative(fuse-ld=gold)Use the bfd linker instead of the default linker
fuse-ld=goldCommon Driver Negative(fuse-ld=bfd)Use the gold linker instead of the default linker
fuse-linker-pluginCommon Undocumented Var(flag_use_linker_plugin)
fvar-trackingCommon Report Var(flag_var_tracking) Init(2) OptimizationPerform variable tracking
fvar-tracking-assignmentsCommon Report Var(flag_var_tracking_assignments) Init(2) OptimizationPerform variable tracking by annotating assignments
fvar-tracking-assignments-toggleCommon Report Var(flag_var_tracking_assignments_toggle) OptimizationToggle -fvar-tracking-assignments
fvar-tracking-uninitCommon Report Var(flag_var_tracking_uninit) OptimizationPerform variable tracking and also tag variables that are uninitialized
fvariable-expansion-in-unrollerCommon Report Var(flag_variable_expansion_in_unroller) OptimizationApply variable expansion when loops are unrolled
fvect-cost-modelCommon RejectNegative Alias(fvect-cost-model=,dynamic)Enables the dynamic vectorizer cost model.  Preserved for backward compatibility.
fvect-cost-model=Common Joined RejectNegative Enum(vect_cost_model) Var(flag_vect_cost_model) Init(VECT_COST_MODEL_DEFAULT) OptimizationSpecifies the cost model for vectorization
fverbose-asmCommon Report Var(flag_verbose_asm)Add extra commentary to assembler output
fversionCommon Driver Alias(-version)
fvisibility-inlines-hiddenC++ ObjC++Marks all inlined functions and methods as having hidden visibility
fvisibility-ms-compatC++ ObjC++ Var(flag_visibility_ms_compat)Changes visibility to match Microsoft Visual Studio by default
fvisibility=Common Joined RejectNegative Enum(symbol_visibility) Var(default_visibility) Init(VISIBILITY_DEFAULT)-fvisibility=[default|internal|hidden|protected]	Set the default symbol visibility
fvptCommon Report Var(flag_value_profile_transformations) OptimizationUse expression value profiles in optimizations
fvtable-gcC++ ObjC++ Ignore Warn(switch %qs is no longer supported)No longer supported
fvtable-thunksC++ ObjC++ Ignore Warn(switch %qs is no longer supported)No longer supported
fvtable-verify=Common Joined RejectNegative Enum(vtv_priority) Var(flag_vtable_verify) Init(VTV_NO_PRIORITY)Validate vtable pointers before using them.
fvtv-countsCommon Var(flag_vtv_counts)Output vtable verification counters.
fvtv-debugCommon Var(flag_vtv_debug)Output vtable verification pointer sets information.
fweakC++ ObjC++ Var(flag_weak) Init(1)Emit common-like symbols as weak symbols
fwebCommon Report Var(flag_web) Init(2) OptimizationConstruct webs and split unrelated uses of single variable
fwhole-fileFortran IgnoreDoes nothing.  Preserved for backward compatibility.
fwhole-programCommon Report Var(flag_whole_program) Init(0)Perform whole program optimizations
fwide-exec-charset=C ObjC C++ ObjC++ Joined RejectNegative-fwide-exec-charset=<cset>	Convert all wide strings and character constants to character set <cset>
fworking-directoryC ObjC C++ ObjC++ Var(flag_working_directory) Init(-1)Generate a #line directive pointing at the current working directory
fworking-directoryFortran
fwpaLTO Driver ReportRun the link-time optimizer in whole program analysis (WPA) mode.
fwpa=LTO Driver RejectNegative Joined Var(flag_wpa)Whole program analysis (WPA) mode with number of parallel jobs specified.
fwrapvCommon Report Var(flag_wrapv) OptimizationAssume signed arithmetic overflow wraps around
fxrefC++ ObjC++ Ignore Warn(switch %qs is no longer supported)No longer supported
fzeeCommon IgnoreDoes nothing.  Preserved for backward compatibility.
fzero-initialized-in-bssCommon Report Var(flag_zero_initialized_in_bss) Init(1)Put zero initialized data in the bss section
fzero-linkObjC ObjC++ Var(flag_zero_link)Generate lazy class lookup (via objc_getClass()) for use in Zero-Link mode
gCommon JoinedOrMissingGenerate debug information in default format
gantAda AdaWhy AdaSCIL Joined UndocumentedCatch typos
gcoffCommon JoinedOrMissing Negative(gdwarf)Generate debug information in COFF format
gdwarfCommon JoinedOrMissing Negative(gdwarf-)Generate debug information in default version of DWARF format
gdwarf-Common Joined UInteger Var(dwarf_version) Init(4) Negative(gstabs)Generate debug information in DWARF v2 (or later) format
gen-declsObjC ObjC++ Var(flag_gen_declaration)Dump declarations to a .decl file
ggdbCommon JoinedOrMissingGenerate debug information in default extended format
ggnu-pubnamesCommon Negative(gno-pubnames) Var(debug_generate_pub_sections, 2)Generate DWARF pubnames and pubtypes sections with GNU extensions.
gnatAda AdaWhy AdaSCIL Joined-gnat<options>	Specify options to GNAT
gnatOAda AdaWhy AdaSCIL SeparateSet name of output ALI file (internal switch)
gno-pubnamesCommon Negative(gpubnames) Var(debug_generate_pub_sections, 0) Init(-1)Don't generate DWARF pubnames and pubtypes sections.
gno-record-gcc-switchesCommon RejectNegative Var(dwarf_record_gcc_switches,0) Init(1)Don't record gcc command line switches in DWARF DW_AT_producer.
gno-split-dwarfCommon Driver RejectNegative Var(dwarf_split_debug_info,0) Init(0)Don't generate debug information in separate .dwo files
gno-strict-dwarfCommon RejectNegative Var(dwarf_strict,0) Init(0)Emit DWARF additions beyond selected version
gpubnamesCommon Negative(ggnu-pubnames) Var(debug_generate_pub_sections, 1)Generate DWARF pubnames and pubtypes sections.
grecord-gcc-switchesCommon RejectNegative Var(dwarf_record_gcc_switches,1)Record gcc command line switches in DWARF DW_AT_producer.
gsplit-dwarfCommon Driver RejectNegative Var(dwarf_split_debug_info,1)Generate debug information in separate .dwo files
gstabsCommon JoinedOrMissing Negative(gstabs+)Generate debug information in STABS format
gstabs+Common JoinedOrMissing Negative(gvms)Generate debug information in extended STABS format
gstrict-dwarfCommon Report RejectNegative Var(dwarf_strict,1)Don't emit DWARF additions beyond selected version
gtoggleCommon Report Var(flag_gtoggle)Toggle debug information generation
gvmsCommon JoinedOrMissing Negative(gxcoff)Generate debug information in VMS format
gxcoffCommon JoinedOrMissing Negative(gxcoff+)Generate debug information in XCOFF format
gxcoff+Common JoinedOrMissing Negative(gcoff)Generate debug information in extended XCOFF format
gzCommon DriverGenerate compressed debug sections
gz=Common Driver Joined Enum(compressed_debug_sections)-gz=<format>	Generate compressed debug sections in format <format>
hDriver Joined Separate
idirafterC ObjC C++ ObjC++ Joined Separate MissingArgError(missing path after %qs)-idirafter <dir>	Add <dir> to the end of the system include path
idirafterFortran Joined Separate
imacrosC ObjC C++ ObjC++ Joined Separate MissingArgError(missing filename after %qs)-imacros <file>	Accept definition of macros in <file>
imultiarchCommon Joined Separate RejectDriver Var(imultiarch) Init(0)-imultiarch <dir>	Set <dir> to be the multiarch include subdirectory
imultilibC ObjC C++ ObjC++ Joined Separate-imultilib <dir>	Set <dir> to be the multilib include subdirectory
imultilibFortran Joined Separate
includeC ObjC C++ ObjC++ Joined Separate MissingArgError(missing filename after %qs)-include <file>	Include the contents of <file> before other files
iplugindir=Common Joined Var(plugindir_string) Init(0)-iplugindir=<dir>	Set <dir> to be the default plugin directory
iprefixC ObjC C++ ObjC++ Joined Separate-iprefix <path>	Specify <path> as a prefix for next two options
iprefixFortran Joined Separate
iquoteC ObjC C++ ObjC++ Joined Separate MissingArgError(missing path after %qs)-iquote <dir>	Add <dir> to the end of the quote include path
iquoteFortran Joined Separate
isysrootC ObjC C++ ObjC++ Joined Separate MissingArgError(missing path after %qs)-isysroot <dir>	Set <dir> to be the system root directory
isysrootFortran Joined Separate
isystemC ObjC C++ ObjC++ Joined Separate MissingArgError(missing path after %qs)-isystem <dir>	Add <dir> to the start of the system include path
isystemFortran Joined Separate
iwithprefixC ObjC C++ ObjC++ Joined Separate-iwithprefix <dir>	Add <dir> to the end of the system include path
iwithprefixbeforeC ObjC C++ ObjC++ Joined Separate-iwithprefixbefore <dir>	Add <dir> to the end of the main include path
k8DriverSynonym of -gnatk8
lDriver Joined Separate
lang-asmC Undocumented RejectDriver
m128bit-long-doubleTarget RejectNegative Report Mask(128BIT_LONG_DOUBLE) Savesizeof(long double) is 16
m16Target RejectNegative Negative(m32) Report Mask(CODE16) InverseMask(ISA_64BIT) Var(ix86_isa_flags) SaveGenerate 16bit i386 code
m32Target RejectNegative Negative(m64) Report InverseMask(ISA_64BIT) Var(ix86_isa_flags) SaveGenerate 32bit i386 code
m3dnowTarget Report Mask(ISA_3DNOW) Var(ix86_isa_flags) SaveSupport 3DNow! built-in functions
m3dnowaTarget Undocumented Mask(ISA_3DNOW_A) Var(ix86_isa_flags) SaveSupport Athlon 3Dnow! built-in functions
m64Target RejectNegative Negative(mx32) Report Mask(ABI_64) Var(ix86_isa_flags) SaveGenerate 64bit x86-64 code
m80387Target Report Mask(80387) SaveUse hardware fp
m8bit-idivTarget Report Mask(USE_8BIT_IDIV) SaveExpand 32bit/64bit integer divide into 8bit unsigned integer divide with run-time check
m96bit-long-doubleTarget RejectNegative Report InverseMask(128BIT_LONG_DOUBLE) Savesizeof(long double) is 12
mabi=Target RejectNegative Joined Var(ix86_abi) Enum(calling_abi) Init(SYSV_ABI)Generate code that conforms to the given ABI
mabmTarget Report Mask(ISA_ABM) Var(ix86_isa_flags) SaveSupport code generation of Advanced Bit Manipulation (ABM) instructions.
maccumulate-outgoing-argsTarget Report Mask(ACCUMULATE_OUTGOING_ARGS) SaveReserve space for outgoing arguments in the function prologue
maddress-mode=Target RejectNegative Joined Enum(pmode) Var(ix86_pmode) Init(PMODE_SI)Use given address mode
madxTarget Report Mask(ISA_ADX) Var(ix86_isa_flags) SaveSupport flag-preserving add-carry instructions
maesTarget Report Mask(ISA_AES) Var(ix86_isa_flags) SaveSupport AES built-in functions and code generation
malign-data=Target RejectNegative Joined Var(ix86_align_data_type) Enum(ix86_align_data) Init(ix86_align_data_type_compat)Use the given data alignment
malign-doubleTarget Report Mask(ALIGN_DOUBLE) SaveAlign some doubles on dword boundary
malign-functions=Target RejectNegative Joined UIntegerFunction starts are aligned to this power of 2
malign-jumps=Target RejectNegative Joined UIntegerJump targets are aligned to this power of 2
malign-loops=Target RejectNegative Joined UIntegerLoop code aligned to this power of 2
malign-stringopsTarget RejectNegative Report InverseMask(NO_ALIGN_STRINGOPS, ALIGN_STRINGOPS) SaveAlign destination of the string operations
mandroidTarget Report Mask(ANDROID) Var(flag_android) Init(ANDROID_DEFAULT ? OPTION_MASK_ANDROID : 0)Generate code for the Android platform.
march=Target RejectNegative Joined Var(ix86_arch_string)Generate code for given CPU
masm=Target RejectNegative Joined Enum(asm_dialect) Var(ix86_asm_dialect) Init(ASM_ATT)Use given assembler dialect
mavxTarget Report Mask(ISA_AVX) Var(ix86_isa_flags) SaveSupport MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2 and AVX built-in functions and code generation
mavx2Target Report Mask(ISA_AVX2) Var(ix86_isa_flags) SaveSupport MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, AVX and AVX2 built-in functions and code generation
mavx256-split-unaligned-loadTarget Report Mask(AVX256_SPLIT_UNALIGNED_LOAD) SaveSplit 32-byte AVX unaligned load
mavx256-split-unaligned-storeTarget Report Mask(AVX256_SPLIT_UNALIGNED_STORE) SaveSplit 32-byte AVX unaligned store
mavx512bwTarget Report Mask(ISA_AVX512BW) Var(ix86_isa_flags) SaveSupport MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, AVX, AVX2 and AVX512F and AVX512BW built-in functions and code generation
mavx512cdTarget Report Mask(ISA_AVX512CD) Var(ix86_isa_flags) SaveSupport MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, AVX, AVX2 and AVX512F and AVX512CD built-in functions and code generation
mavx512dqTarget Report Mask(ISA_AVX512DQ) Var(ix86_isa_flags) SaveSupport MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, AVX, AVX2 and AVX512F and AVX512DQ built-in functions and code generation
mavx512erTarget Report Mask(ISA_AVX512ER) Var(ix86_isa_flags) SaveSupport MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, AVX, AVX2 and AVX512F and AVX512ER built-in functions and code generation
mavx512fTarget Report Mask(ISA_AVX512F) Var(ix86_isa_flags) SaveSupport MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, AVX, AVX2 and AVX512F built-in functions and code generation
mavx512ifmaTarget Report Mask(ISA_AVX512IFMA) Var(ix86_isa_flags) SaveSupport MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, AVX, AVX2 and AVX512F and AVX512IFMA built-in functions and code generation
mavx512pfTarget Report Mask(ISA_AVX512PF) Var(ix86_isa_flags) SaveSupport MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, AVX, AVX2 and AVX512F and AVX512PF built-in functions and code generation
mavx512vbmiTarget Report Mask(ISA_AVX512VBMI) Var(ix86_isa_flags) SaveSupport MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, AVX, AVX2 and AVX512F and AVX512VBMI built-in functions and code generation
mavx512vlTarget Report Mask(ISA_AVX512VL) Var(ix86_isa_flags) SaveSupport MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, AVX, AVX2 and AVX512F and AVX512VL built-in functions and code generation
mbionicTarget Report RejectNegative Var(linux_libc,LIBC_BIONIC) Init(DEFAULT_LIBC) Negative(mglibc)Use Bionic C library
mbmiTarget Report Mask(ISA_BMI) Var(ix86_isa_flags) SaveSupport BMI built-in functions and code generation
mbmi2Target Report Mask(ISA_BMI2) Var(ix86_isa_flags) SaveSupport BMI2 built-in functions and code generation
mbranch-cost=Target RejectNegative Joined UInteger Var(ix86_branch_cost)Branches are this expensive (1-5, arbitrary units)
mcldTarget Report Mask(CLD) SaveGenerate cld instruction in the function prologue.
mclflushoptTarget Report Mask(ISA_CLFLUSHOPT) Var(ix86_isa_flags) SaveSupport CLFLUSHOPT instructions
mclwbTarget Report Mask(ISA_CLWB) Var(ix86_isa_flags) SaveSupport CLWB instruction
mcmodel=Target RejectNegative Joined Enum(cmodel) Var(ix86_cmodel) Init(CM_32)Use given x86-64 code model
mcpu=Target RejectNegative Joined Undocumented Alias(mtune=) Warn(%<-mcpu=%> is deprecated; use %<-mtune=%> or %<-march=%> instead)
mcrc32Target Report Mask(ISA_CRC32) Var(ix86_isa_flags) SaveSupport code generation of crc32 instruction.
mcx16Target Report Mask(ISA_CX16) Var(ix86_isa_flags) SaveSupport code generation of cmpxchg16b instruction.
mdispatch-schedulerTarget RejectNegative Var(flag_dispatch_scheduler)Do dispatch scheduling if processor is bdver1 or bdver2 or bdver3 or bdver4 and Haifa schedulingis selected.
mdump-tune-featuresTarget RejectNegative Var(ix86_dump_tunes) Init(0)
mf16cTarget Report Mask(ISA_F16C) Var(ix86_isa_flags) SaveSupport F16C built-in functions and code generation
mfancy-math-387Target RejectNegative Report InverseMask(NO_FANCY_MATH_387, USE_FANCY_MATH_387) SaveGenerate sin, cos, sqrt for FPU
mfentryTarget Report Var(flag_fentry) Init(-1)Emit profiling counter call at function entry before prologue.
mfmaTarget Report Mask(ISA_FMA) Var(ix86_isa_flags) SaveSupport MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, AVX and FMA built-in functions and code generation
mfma4Target Report Mask(ISA_FMA4) Var(ix86_isa_flags) SaveSupport FMA4 built-in functions and code generation 
mforce-drapTarget Report Var(ix86_force_drap)Always use Dynamic Realigned Argument Pointer (DRAP) to realign stack
mfp-ret-in-387Target Report Mask(FLOAT_RETURNS) SaveReturn values of functions in FPU registers
mfpmath=Target RejectNegative Joined Var(ix86_fpmath) Enum(fpmath_unit) Init(FPMATH_387) SaveGenerate floating point mathematics using given instruction set
mfsgsbaseTarget Report Mask(ISA_FSGSBASE) Var(ix86_isa_flags) SaveSupport FSGSBASE built-in functions and code generation
mfused-maddTarget Undocumented Alias(ffp-contract=, fast, off) Warn(%<-mfused-madd%> is deprecated; use %<-ffp-contract=%> instead)
mfxsrTarget Report Mask(ISA_FXSR) Var(ix86_isa_flags) SaveSupport FXSAVE and FXRSTOR instructions
mglibcTarget Report RejectNegative Var(linux_libc,LIBC_GLIBC) Negative(muclibc)Use GNU C library
mhard-floatTarget RejectNegative Mask(80387) SaveUse hardware fp
mhleTarget Report Mask(ISA_HLE) Var(ix86_isa_flags) SaveSupport Hardware Lock Elision prefixes
mieee-fpTarget Report Mask(IEEE_FP) SaveUse IEEE math for fp comparisons
mincoming-stack-boundary=Target RejectNegative Joined UInteger Var(ix86_incoming_stack_boundary_arg)Assume incoming stack aligned to this power of 2
minline-all-stringopsTarget Report Mask(INLINE_ALL_STRINGOPS) SaveInline all known string operations
minline-stringops-dynamicallyTarget Report Mask(INLINE_STRINGOPS_DYNAMICALLY) SaveInline memset/memcpy string operations, but perform inline version only for small blocks
mintel-syntaxTarget Undocumented Alias(masm=, intel, att) Warn(%<-mintel-syntax%> and %<-mno-intel-syntax%> are deprecated; use %<-masm=intel%> and %<-masm=att%> instead)
mlarge-data-threshold=Target RejectNegative Joined UInteger Var(ix86_section_threshold) Init(DEFAULT_LARGE_SECTION_THRESHOLD)Data greater than given threshold will go into .ldata section in x86-64 medium model
mlong-double-128Target Report RejectNegative Negative(mlong-double-80) Mask(LONG_DOUBLE_128) InverseMask(LONG_DOUBLE_64) SaveUse 128-bit long double
mlong-double-64Target Report RejectNegative Negative(mlong-double-128) Mask(LONG_DOUBLE_64) InverseMask(LONG_DOUBLE_128) SaveUse 64-bit long double
mlong-double-80Target Report RejectNegative Negative(mlong-double-64) InverseMask(LONG_DOUBLE_64) SaveUse 80-bit long double
mlwpTarget Report Mask(ISA_LWP) Var(ix86_isa_flags) SaveSupport LWP built-in functions and code generation 
mlzcntTarget Report Mask(ISA_LZCNT) Var(ix86_isa_flags) SaveSupport LZCNT built-in function and code generation
mmemcpy-strategy=Target RejectNegative Joined Var(ix86_tune_memcpy_strategy)Specify memcpy expansion strategy when expected size is known
mmemset-strategy=Target RejectNegative Joined Var(ix86_tune_memset_strategy)Specify memset expansion strategy when expected size is known
mmmxTarget Report Mask(ISA_MMX) Var(ix86_isa_flags) SaveSupport MMX built-in functions
mmovbeTarget Report Mask(ISA_MOVBE) Var(ix86_isa_flags) SaveSupport code generation of movbe instruction.
mmpxTarget Report Mask(ISA_MPX) Var(ix86_isa_flags) SaveSupport MPX code generation
mms-bitfieldsTarget Report Mask(MS_BITFIELD_LAYOUT) SaveUse native (MS) bitfield layout
mno-align-stringopsTarget RejectNegative Report Mask(NO_ALIGN_STRINGOPS) Undocumented Save
mno-defaultTarget RejectNegative Var(ix86_tune_no_default) Init(0)Clear all tune features
mno-fancy-math-387Target RejectNegative Report Mask(NO_FANCY_MATH_387) Undocumented Save
mno-push-argsTarget RejectNegative Report Mask(NO_PUSH_ARGS) Undocumented Save
mno-red-zoneTarget RejectNegative Report Mask(NO_RED_ZONE) Undocumented Save
mno-sse4Target RejectNegative Report InverseMask(ISA_SSE4_1) Var(ix86_isa_flags) SaveDo not support SSE4.1 and SSE4.2 built-in functions and code generation
mnop-mcountTarget Report Var(flag_nop_mcount) Init(0)Generate mcount/__fentry__ calls as nops. To activate they need to bepatched in.
momit-leaf-frame-pointerTarget Report Mask(OMIT_LEAF_FRAME_POINTER) SaveOmit the frame pointer in leaf functions
mpc32Target RejectNegative ReportSet 80387 floating-point precision to 32-bit
mpc64Target RejectNegative ReportSet 80387 floating-point precision to 64-bit
mpc80Target RejectNegative ReportSet 80387 floating-point precision to 80-bit
mpclmulTarget Report Mask(ISA_PCLMUL) Var(ix86_isa_flags) SaveSupport PCLMUL built-in functions and code generation
mpcommitTarget Report Mask(ISA_PCOMMIT) Var(ix86_isa_flags) SaveSupport PCOMMIT instruction
mpopcntTarget Report Mask(ISA_POPCNT) Var(ix86_isa_flags) SaveSupport code generation of popcnt instruction.
mprefer-avx128Target Report Mask(PREFER_AVX128) SAVEUse 128-bit AVX instructions instead of 256-bit AVX instructions in the auto-vectorizer.
mpreferred-stack-boundary=Target RejectNegative Joined UInteger Var(ix86_preferred_stack_boundary_arg)Attempt to keep stack aligned to this power of 2
mprefetchwt1Target Report Mask(ISA_PREFETCHWT1) Var(ix86_isa_flags) SaveSupport PREFETCHWT1 built-in functions and code generation
mprfchwTarget Report Mask(ISA_PRFCHW) Var(ix86_isa_flags) SaveSupport PREFETCHW instruction
mpush-argsTarget Report InverseMask(NO_PUSH_ARGS, PUSH_ARGS) SaveUse push instructions to save outgoing arguments
mrdrndTarget Report Mask(ISA_RDRND) Var(ix86_isa_flags) SaveSupport RDRND built-in functions and code generation
mrdseedTarget Report Mask(ISA_RDSEED) Var(ix86_isa_flags) SaveSupport RDSEED instruction
mrecipTarget Report Mask(RECIP) SaveGenerate reciprocals instead of divss and sqrtss.
mrecip=Target Report RejectNegative Joined Var(ix86_recip_name)Control generation of reciprocal estimates.
mrecord-mcountTarget Report Var(flag_record_mcount) Init(0)Generate __mcount_loc section with all mcount or __fentry__ calls.
mred-zoneTarget RejectNegative Report InverseMask(NO_RED_ZONE, RED_ZONE) SaveUse red-zone in the x86-64 code
mregparm=Target RejectNegative Joined UInteger Var(ix86_regparm)Number of registers used to pass integer arguments
mrtdTarget Report Mask(RTD) SaveAlternate calling convention
mrtmTarget Report Mask(ISA_RTM) Var(ix86_isa_flags) SaveSupport RTM built-in functions and code generation
msahfTarget Report Mask(ISA_SAHF) Var(ix86_isa_flags) SaveSupport code generation of sahf instruction in 64bit x86-64 code.
mshaTarget Report Mask(ISA_SHA) Var(ix86_isa_flags) SaveSupport SHA1 and SHA256 built-in functions and code generation
mskip-rax-setupTarget Report Var(flag_skip_rax_setup) Init(0)Skip setting up RAX register when passing variable arguments.
msoft-floatTarget InverseMask(80387) SaveDo not use hardware fp
msseTarget Report Mask(ISA_SSE) Var(ix86_isa_flags) SaveSupport MMX and SSE built-in functions and code generation
msse2Target Report Mask(ISA_SSE2) Var(ix86_isa_flags) SaveSupport MMX, SSE and SSE2 built-in functions and code generation
msse2avxTarget Report Var(ix86_sse2avx)Encode SSE instructions with VEX prefix
msse3Target Report Mask(ISA_SSE3) Var(ix86_isa_flags) SaveSupport MMX, SSE, SSE2 and SSE3 built-in functions and code generation
msse4Target RejectNegative Report Mask(ISA_SSE4_2) Var(ix86_isa_flags) SaveSupport MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1 and SSE4.2 built-in functions and code generation
msse4.1Target Report Mask(ISA_SSE4_1) Var(ix86_isa_flags) SaveSupport MMX, SSE, SSE2, SSE3, SSSE3 and SSE4.1 built-in functions and code generation
msse4.2Target Report Mask(ISA_SSE4_2) Var(ix86_isa_flags) SaveSupport MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1 and SSE4.2 built-in functions and code generation
msse4aTarget Report Mask(ISA_SSE4A) Var(ix86_isa_flags) SaveSupport MMX, SSE, SSE2, SSE3 and SSE4A built-in functions and code generation
msse5Target Undocumented Alias(mavx) Warn(%<-msse5%> was removed)
msseregparmTarget RejectNegative Mask(SSEREGPARM) SaveUse SSE register passing conventions for SF and DF mode
mssse3Target Report Mask(ISA_SSSE3) Var(ix86_isa_flags) SaveSupport MMX, SSE, SSE2, SSE3 and SSSE3 built-in functions and code generation
mstack-arg-probeTarget Report Mask(STACK_PROBE) SaveEnable stack probing
mstack-protector-guard=Target RejectNegative Joined Enum(stack_protector_guard) Var(ix86_stack_protector_guard) Init(SSP_TLS)Use given stack-protector guard
mstackrealignTarget Report Var(ix86_force_align_arg_pointer) Init(-1)Realign stack in prologue
mstringop-strategy=Target RejectNegative Joined Enum(stringop_alg) Var(ix86_stringop_alg) Init(no_stringop)Chose strategy to generate stringop using
mtbmTarget Report Mask(ISA_TBM) Var(ix86_isa_flags) SaveSupport TBM built-in functions and code generation
mtls-dialect=Target RejectNegative Joined Var(ix86_tls_dialect) Enum(tls_dialect) Init(TLS_DIALECT_GNU)Use given thread-local storage dialect
mtls-direct-seg-refsTarget Report Mask(TLS_DIRECT_SEG_REFS)Use direct references against %gs when accessing tls data
mtune-ctrl=Target RejectNegative Joined Var(ix86_tune_ctrl_string)Fine grain control of tune features
mtune=Target RejectNegative Joined Var(ix86_tune_string)Schedule code for given CPU
muclibcTarget Report RejectNegative Var(linux_libc,LIBC_UCLIBC) Negative(mbionic)Use uClibc C library
mveclibabi=Target RejectNegative Joined Var(ix86_veclibabi_type) Enum(ix86_veclibabi) Init(ix86_veclibabi_type_none)Vector library ABI to use
mvect8-ret-in-memTarget Report Mask(VECT8_RETURNS) SaveReturn 8-byte vectors in memory
mvzeroupperTarget Report Mask(VZEROUPPER) SaveGenerate vzeroupper instruction before a transfer of control flow out ofthe function.
mx32Target RejectNegative Negative(m16) Report Mask(ABI_X32) Var(ix86_isa_flags) SaveGenerate 32bit x86-64 code
mxopTarget Report Mask(ISA_XOP) Var(ix86_isa_flags) SaveSupport XOP built-in functions and code generation 
mxsaveTarget Report Mask(ISA_XSAVE) Var(ix86_isa_flags) SaveSupport XSAVE and XRSTOR instructions
mxsavecTarget Report Mask(ISA_XSAVEC) Var(ix86_isa_flags) SaveSupport XSAVEC instructions
mxsaveoptTarget Report Mask(ISA_XSAVEOPT) Var(ix86_isa_flags) SaveSupport XSAVEOPT instruction
mxsavesTarget Report Mask(ISA_XSAVES) Var(ix86_isa_flags) SaveSupport XSAVES and XRSTORS instructions
nDriver
no-canonical-prefixesDriver
no-integrated-cppDriver
nocppFortran Negative(cpp)Disable preprocessing
nodefaultlibsDriver
nostartfilesDriver
nostdincAda AdaWhy AdaSCIL RejectNegative
nostdincC ObjC C++ ObjC++Do not search standard system include directories (those specified with -isystem will still be used)
nostdincFortran
nostdinc++C++ ObjC++Do not search standard system include directories for C++
nostdlibAda AdaWhy AdaSCILDo not look for object files in standard path
nostdlibDriver
oC ObjC C++ ObjC++ Joined Separate
oCommon Driver Joined Separate Var(asm_file_name) MissingArgError(missing filename after %qs)-o <file>	Place output into <file>
oFortran Joined Separate
oGo Joined Separate
pCommon Var(profile_flag)Enable function profiling
pass-exit-codesDriver Var(pass_exit_codes)
pedanticC ObjC C++ ObjC++ Alias(Wpedantic)
pedanticCommon Alias(Wpedantic)
pedantic-errorsCommon Var(flag_pedantic_errors)Like -pedantic but issue them as errors
pgDriver
pieDriver RejectNegative Negative(shared)Create a position independent executable
pipeDriver Var(use_pipes)
posixDriver
print-file-name=Driver JoinedOrMissing Var(print_file_name)
print-libgcc-file-nameDriver
print-multi-directoryDriver Var(print_multi_directory)
print-multi-libDriver Var(print_multi_lib)
print-multi-os-directoryDriver Var(print_multi_os_directory)
print-multiarchDriver Var(print_multiarch)
print-objc-runtime-infoObjC ObjC++Generate C header of platform-specific features
print-prog-name=Driver JoinedOrMissing Var(print_prog_name)
print-search-dirsDriver Var(print_search_dirs)
print-sysrootDriver Var(print_sysroot)
print-sysroot-headers-suffixDriver Var(print_sysroot_headers_suffix)
profileDriver
pthreadDriver
quietCommon Var(quiet_flag) RejectDriverDo not display functions compiled or elapsed time
rDriver
rdynamicDriver
remapC ObjC C++ ObjC++Remap file names when including files
sDriver
s-bc-abiDriver
save-tempsDriver
save-temps=Driver Joined
sharedDriver RejectNegative Negative(pie)Create a shared library
shared-libgccDriver
specsDriver Separate Alias(specs=)
specs=Driver Joined
staticDriver
static-libasanDriver
static-libgccDriver
static-libgcjDriver
static-libgfortranDriver
static-libgfortranFortranStatically link the GNU Fortran helper library (libgfortran)
static-libgoDriver
static-liblsanDriver
static-libmpxDriver
static-libmpxwrappersDriver
static-libstdc++Driver
static-libtsanDriver
static-libubsanDriver
std=c++03C++ ObjC++ Alias(std=c++98)Conform to the ISO 1998 C++ standard revised by the 2003 technical corrigendum
std=c++0xC++ ObjC++ Alias(std=c++11) UndocumentedDeprecated in favor of -std=c++11
std=c++11C++ ObjC++Conform to the ISO 2011 C++ standard
std=c++14C++ ObjC++ UndocumentedConform to the ISO 2014 C++ standard (experimental and incomplete support)
std=c++17C++ ObjC++ Alias(std=c++1z) Undocumented
std=c++1yC++ ObjC++ Alias(std=c++14) UndocumentedDeprecated in favor of -std=c++14
std=c++1zC++ ObjC++Conform to the ISO 2017(?) C++ draft standard (experimental and incomplete support)
std=c++98C++ ObjC++Conform to the ISO 1998 C++ standard revised by the 2003 technical corrigendum
std=c11C ObjCConform to the ISO 2011 C standard (experimental and incomplete support)
std=c1xC ObjC Alias(std=c11)Deprecated in favor of -std=c11
std=c89C ObjC Alias(std=c90)Conform to the ISO 1990 C standard
std=c90C ObjCConform to the ISO 1990 C standard
std=c99C ObjCConform to the ISO 1999 C standard
std=c9xC ObjC Alias(std=c99)Deprecated in favor of -std=c99
std=f2003FortranConform to the ISO Fortran 2003 standard
std=f2008FortranConform to the ISO Fortran 2008 standard
std=f2008tsFortranConform to the ISO Fortran 2008 standard including TS 29113
std=f95FortranConform to the ISO Fortran 95 standard
std=gnuFortranConform to nothing in particular
std=gnu++03C++ ObjC++ Alias(std=gnu++98)Conform to the ISO 1998 C++ standard revised by the 2003 technicalcorrigendum with GNU extensions
std=gnu++0xC++ ObjC++ Alias(std=gnu++11)Deprecated in favor of -std=gnu++11
std=gnu++11C++ ObjC++Conform to the ISO 2011 C++ standard with GNU extensions (experimental and incomplete support)
std=gnu++14C++ ObjC++Conform to the ISO 2014 C++ standard with GNU extensions (experimental and incomplete support)
std=gnu++17C++ ObjC++ Alias(std=gnu++1z) Undocumented
std=gnu++1yC++ ObjC++ Alias(std=gnu++14) Undocumented
std=gnu++1zC++ ObjC++Conform to the ISO 201z(7?) C++ draft standard with GNU extensions (experimental and incomplete support)
std=gnu++98C++ ObjC++Conform to the ISO 1998 C++ standard revised by the 2003 technicalcorrigendum with GNU extensions
std=gnu11C ObjCConform to the ISO 2011 C standard with GNU extensions (experimental and incomplete support)
std=gnu1xC ObjC Alias(std=gnu11)Deprecated in favor of -std=gnu11
std=gnu89C ObjC Alias(std=gnu90)Conform to the ISO 1990 C standard with GNU extensions
std=gnu90C ObjCConform to the ISO 1990 C standard with GNU extensions
std=gnu99C ObjCConform to the ISO 1999 C standard with GNU extensions
std=gnu9xC ObjC Alias(std=gnu99)Deprecated in favor of -std=gnu99
std=iso9899:1990C ObjC Alias(std=c90)Conform to the ISO 1990 C standard
std=iso9899:199409C ObjCConform to the ISO 1990 C standard as amended in 1994
std=iso9899:1999C ObjC Alias(std=c99)Conform to the ISO 1999 C standard
std=iso9899:199xC ObjC Alias(std=c99)Deprecated in favor of -std=iso9899:1999
std=iso9899:2011C ObjC Alias(std=c11)Conform to the ISO 2011 C standard (experimental and incomplete support)
std=legacyFortranAccept extensions to support legacy code
symbolicDriver
tDriver
timeDriver Var(report_times)
time=Driver JoinedOrMissing
tno-android-ccDriver
tno-android-ldDriver
traditionalDriver
traditional-cppC ObjC C++ ObjC++Enable traditional preprocessing
trigraphsC ObjC C++ ObjC++-trigraphs	Support ISO C trigraphs
uDriver Joined Separate
undefC ObjC C++ ObjC++ Var(flag_undef)Do not predefine system-specific and GCC-specific macros
undefDriver
undefFortran
vC ObjC C++ ObjC++
vCommon Driver Var(verbose_flag)Enable verbose output
vFortran
versionCommon Var(version_flag) RejectDriverDisplay the compiler's version
versionJava RejectDriver
wC ObjC C++ ObjC++
wCommon Var(inhibit_warnings)Suppress warnings
wrapperDriver Separate Var(wrapper_string)
xDriver Joined Separate
zDriver Joined Separate