-fno-nonansi-builtins -fnothrow-opt -fno-operator-names @gol
-fno-optional-diags -fpermissive @gol
-fno-pretty-templates @gol
--frepo -fno-rtti -fsized-deallocation @gol
+-fno-rtti -fsized-deallocation @gol
-ftemplate-backtrace-limit=@var{n} @gol
-ftemplate-depth=@var{n} @gol
-fno-threadsafe-statics -fuse-cxa-atexit @gol
-Wno-non-template-friend -Wold-style-cast @gol
-Woverloaded-virtual -Wno-pmf-conversions @gol
-Wno-class-conversion -Wno-terminate @gol
--Wsign-promo -Wvirtual-inheritance}
+-Wsign-promo -Wvirtual-inheritance -Wvolatile}
@item Objective-C and Objective-C++ Language Options
@xref{Objective-C and Objective-C++ Dialect Options,,Options Controlling
@gccoptlist{-fmessage-length=@var{n} @gol
-fdiagnostics-show-location=@r{[}once@r{|}every-line@r{]} @gol
-fdiagnostics-color=@r{[}auto@r{|}never@r{|}always@r{]} @gol
+-fdiagnostics-urls=@r{[}auto@r{|}never@r{|}always@r{]} @gol
-fdiagnostics-format=@r{[}text@r{|}json@r{]} @gol
-fno-diagnostics-show-option -fno-diagnostics-show-caret @gol
-fno-diagnostics-show-labels -fno-diagnostics-show-line-numbers @gol
-Wno-builtin-declaration-mismatch @gol
-Wno-builtin-macro-redefined -Wc90-c99-compat -Wc99-c11-compat @gol
-Wc++-compat -Wc++11-compat -Wc++14-compat -Wc++17-compat @gol
+-Wc++20-compat @gol
-Wcast-align -Wcast-align=strict -Wcast-function-type -Wcast-qual @gol
-Wchar-subscripts -Wcatch-value -Wcatch-value=@var{n} @gol
-Wclobbered -Wcomment -Wconditionally-supported @gol
-Wno-discarded-qualifiers -Wno-discarded-array-qualifiers @gol
-Wno-div-by-zero -Wdouble-promotion @gol
-Wduplicated-branches -Wduplicated-cond @gol
--Wempty-body -Wenum-compare -Wno-endif-labels -Wexpansion-to-defined @gol
+-Wempty-body -Wenum-compare -Wenum-conversion @gol
+-Wno-endif-labels -Wexpansion-to-defined @gol
-Werror -Werror=* -Wextra-semi -Wfatal-errors @gol
-Wfloat-equal -Wformat -Wformat=2 @gol
-Wno-format-contains-nul -Wno-format-extra-args @gol
-Wsizeof-pointer-memaccess -Wsizeof-array-argument @gol
-Wstack-protector -Wstack-usage=@var{byte-size} -Wstrict-aliasing @gol
-Wstrict-aliasing=n -Wstrict-overflow -Wstrict-overflow=@var{n} @gol
+-Wstring-compare @gol
-Wstringop-overflow=@var{n} -Wstringop-truncation -Wsubobject-linkage @gol
-Wsuggest-attribute=@r{[}pure@r{|}const@r{|}noreturn@r{|}format@r{|}malloc@r{]} @gol
-Wsuggest-final-types @gol -Wsuggest-final-methods -Wsuggest-override @gol
-falign-jumps[=@var{n}[:@var{m}:[@var{n2}[:@var{m2}]]]] @gol
-falign-labels[=@var{n}[:@var{m}:[@var{n2}[:@var{m2}]]]] @gol
-falign-loops[=@var{n}[:@var{m}:[@var{n2}[:@var{m2}]]]] @gol
+-fallow-store-data-races @gol
-fassociative-math -fauto-profile -fauto-profile[=@var{path}] @gol
-fauto-inc-dec -fbranch-probabilities @gol
--fbranch-target-load-optimize -fbranch-target-load-optimize2 @gol
--fbtr-bb-exclusive -fcaller-saves @gol
+-fcaller-saves @gol
-fcombine-stack-adjustments -fconserve-stack @gol
-fcompare-elim -fcprop-registers -fcrossjumping @gol
-fcse-follow-jumps -fcse-skip-blocks -fcx-fortran-rules @gol
-march=@var{name} -mcpu=@var{name} -mtune=@var{name} @gol
-moverride=@var{string} -mverbose-cost-dump @gol
-mstack-protector-guard=@var{guard} -mstack-protector-guard-reg=@var{sysreg} @gol
--mstack-protector-guard-offset=@var{offset} -mtrack-speculation }
+-mstack-protector-guard-offset=@var{offset} -mtrack-speculation @gol
+-moutline-atomics }
@emph{Adapteva Epiphany Options}
@gccoptlist{-mhalf-reg-file -mprefer-short-insn-regs @gol
-mrestrict-it @gol
-mverbose-cost-dump @gol
-mpure-code @gol
--mcmse}
+-mcmse @gol
+-mfdpic}
@emph{AVR Options}
@gccoptlist{-mmcu=@var{mcu} -mabsdata -maccumulate-args @gol
-msmall-text -mlarge-text @gol
-mmemory-latency=@var{time}}
+@emph{eBPF Options}
+@gccoptlist{-mbig-endian -mlittle-endian -mkernel=@var{version}
+-mframe-limit=@var{bytes}}
+
@emph{FR30 Options}
@gccoptlist{-msmall-model -mno-lsim}
-mfix-at697f -mfix-ut699 -mfix-ut700 -mfix-gr712rc @gol
-mlra -mno-lra}
-@emph{SPU Options}
-@gccoptlist{-mwarn-reloc -merror-reloc @gol
--msafe-dma -munsafe-dma @gol
--mbranch-hints @gol
--msmall-mem -mlarge-mem -mstdmain @gol
--mfixed-range=@var{register-range} @gol
--mea32 -mea64 @gol
--maddress-space-conversion -mno-address-space-conversion @gol
--mcache-size=@var{cache-size} @gol
--matomic-updates -mno-atomic-updates}
-
@emph{System V Options}
@gccoptlist{-Qy -Qn -YP,@var{paths} -Ym,@var{dir}}
@samp{new (nothrow)}.
@item -fconcepts
+@itemx -fconcepts-ts
@opindex fconcepts
-Enable support for the C++ Extensions for Concepts Technical
-Specification, ISO 19217 (2015), which allows code like
+@opindex fconcepts-ts
+Below @option{-std=c++2a}, @option{-fconcepts} enables support for the
+C++ Extensions for Concepts Technical Specification, ISO 19217 (2015).
-@smallexample
-template <class T> concept bool Addable = requires (T t) @{ t + t; @};
-template <Addable T> T add (T a, T b) @{ return a + b; @}
-@end smallexample
+With @option{-std=c++2a} and above, Concepts are part of the language
+standard, so @option{-fconcepts} defaults to on. But the standard
+specification of Concepts differs significantly from the TS, so some
+constructs that were allowed in the TS but didn't make it into the
+standard can still be enabled by @option{-fconcepts-ts}.
@item -fconstexpr-depth=@var{n}
@opindex fconstexpr-depth
evaluation might take too long.
The default is 33554432 (1<<25).
-@item -fdeduce-init-list
-@opindex fdeduce-init-list
-Enable deduction of a template type parameter as
-@code{std::initializer_list} from a brace-enclosed initializer list, i.e.@:
-
-@smallexample
-template <class T> auto forward(T t) -> decltype (realfn (t))
-@{
- return realfn (t);
-@}
-
-void f()
-@{
- forward(@{1,2@}); // call forward<std::initializer_list<int>>
-@}
-@end smallexample
-
-This deduction was implemented as a possible extension to the
-originally proposed semantics for the C++11 standard, but was not part
-of the final standard, so it is disabled by default. This option is
-deprecated, and may be removed in a future version of G++.
-
@item -fno-elide-constructors
@opindex fno-elide-constructors
@opindex felide-constructors
behaviors make it harder to understand the error message rather than
easier, you can use @option{-fno-pretty-templates} to disable them.
-@item -frepo
-@opindex frepo
-Enable automatic template instantiation at link time. This option also
-implies @option{-fno-implicit-templates}. @xref{Template
-Instantiation}, for more information.
-
@item -fno-rtti
@opindex fno-rtti
@opindex frtti
Disable the warning about the case when a conversion function converts an
object to the same type, to a base class of that type, or to void; such
a conversion function will never be called.
+
+@item -Wvolatile @r{(C++ and Objective-C++ only)}
+@opindex Wvolatile
+@opindex Wno-volatile
+Warn about deprecated uses of the @code{volatile} qualifier. This includes
+postfix and prefix @code{++} and @code{--} expressions of
+@code{volatile}-qualified types, using simple assignments where the left
+operand is a @code{volatile}-qualified non-class type for their value,
+compound assignments where the left operand is a @code{volatile}-qualified
+non-class type, @code{volatile}-qualified function return type,
+@code{volatile}-qualified parameter type, and structured bindings of a
+@code{volatile}-qualified type. This usage was deprecated in C++20.
+
+Enabled by default with @option{-std=c++2a}.
@end table
@node Objective-C and Objective-C++ Dialect Options
arguments in the C++ frontend.
@end table
+@item -fdiagnostics-urls[=@var{WHEN}]
+@opindex fdiagnostics-urls
+@cindex urls
+Use escape sequences to embed URLs in diagnostics. For example, when
+@option{-fdiagnostics-show-option} emits text showing the command-line
+option controlling a diagnostic, embed a URL for documentation of that
+option.
+
+@var{WHEN} is @samp{never}, @samp{always}, or @samp{auto}.
+The default is @samp{auto}, which means to use URL escape sequences only
+when the standard error is a terminal.
+
@item -fno-diagnostics-show-option
@opindex fno-diagnostics-show-option
@opindex fdiagnostics-show-option
],
"message": "this \u2018if\u2019 clause does not guard...",
"option": "-Wmisleading-indentation",
+ "option_url": "https://gcc.gnu.org/onlinedocs/gcc/Warning-Options.html#index-Wmisleading-indentation",
"children": [
@{
"kind": "note",
-Wcomment @gol
-Wduplicate-decl-specifier @r{(C and Objective-C only)} @gol
-Wenum-compare @r{(in C/ObjC; this is on by default in C++)} @gol
+-Wenum-conversion @r{in C/ObjC;} @gol
-Wformat @gol
-Wint-in-bool-context @gol
-Wimplicit @r{(C and Objective-C only)} @gol
-Wold-style-declaration @r{(C only)} @gol
-Woverride-init @gol
-Wsign-compare @r{(C only)} @gol
+-Wstring-compare @gol
-Wredundant-move @r{(only for C++)} @gol
-Wtype-limits @gol
-Wuninitialized @gol
@item -Wuninitialized
@opindex Wuninitialized
@opindex Wno-uninitialized
-Warn if an automatic variable is used without first being initialized
-or if a variable may be clobbered by a @code{setjmp} call. In C++,
-warn if a non-static reference or non-static @code{const} member
-appears in a class without constructors.
+Warn if an automatic variable is used without first being initialized.
+In C++, warn if a non-static reference or non-static @code{const}
+member appears in a class without constructors.
If you want to warn about code that uses the uninitialized value of the
variable in its own initializer, use the @option{-Winit-self} option.
-These warnings occur for individual uninitialized or clobbered
-elements of structure, union or array variables as well as for
-variables that are uninitialized or clobbered as a whole. They do
-not occur for variables or elements declared @code{volatile}. Because
-these warnings depend on optimization, the exact variables or elements
-for which there are warnings depends on the precise optimization
-options and version of GCC used.
+These warnings occur for individual uninitialized elements of
+structure, union or array variables as well as for variables that are
+uninitialized as a whole. They do not occur for variables or elements
+declared @code{volatile}. Because these warnings depend on
+optimization, the exact variables or elements for which there are
+warnings depend on the precise optimization options and version of GCC
+used.
Note that there may be no warning about a variable that is used only
to compute a value that itself is never used, because such
false positives.
@end table
+@item -Wstring-compare
+@opindex Wstring-compare
+@opindex Wno-string-compare
+Warn for calls to @code{strcmp} and @code{strncmp} whose result is
+determined to be either zero or non-zero in tests for such equality
+owing to the length of one argument being greater than the size of
+the array the other argument is stored in (or the bound in the case
+of @code{strncmp}). Such calls could be mistakes. For example,
+the call to @code{strcmp} below is diagnosed because its result is
+necessarily non-zero irrespective of the contents of the array @code{a}.
+
+@smallexample
+extern char a[4];
+void f (char *d)
+@{
+ strcpy (d, "string");
+ @dots{}
+ if (0 == strcmp (a, d)) // cannot be true
+ puts ("a and d are the same");
+@}
+@end smallexample
+
+@option{-Wstring-compare} is enabled by @option{-Wextra}.
+
@item -Wstringop-overflow
@itemx -Wstringop-overflow=@var{type}
@opindex Wstringop-overflow
Objective-C method.
@item -Wshadow=global
-@opindex Wshadow=local
+@opindex Wshadow=global
The default for @option{-Wshadow}. Warns for any (global) shadowing.
+This warning is enabled by @option{-Wshadow=global}.
@item -Wshadow=local
@opindex Wshadow=local
Warn when a local variable shadows another local variable or parameter.
-This warning is enabled by @option{-Wshadow=global}.
+This warning is enabled by @option{-Wshadow=local}.
@item -Wshadow=compatible-local
@opindex Wshadow=compatible-local
warning. So not warning (about shadowing) in this case will not lead to
undetected bugs. Use of this flag instead of @option{-Wshadow=local} can
possibly reduce the number of warnings triggered by intentional shadowing.
+Note that this does also mean that shadowing @code{const char *i} by
+@code{char *i} will not emit a warning.
-This warning is enabled by @option{-Wshadow=local}.
+This warning is enabled by @option{-Wshadow=compatible-local}.
@item -Wlarger-than=@var{byte-size}
@opindex Wlarger-than=
Warn about C++ constructs whose meaning differs between ISO C++ 2014
and ISO C++ 2017. This warning is enabled by @option{-Wall}.
+@item -Wc++20-compat @r{(C++ and Objective-C++ only)}
+@opindex Wc++20-compat
+@opindex Wno-c++20-compat
+Warn about C++ constructs whose meaning differs between ISO C++ 2017
+and ISO C++ 2020. This warning is enabled by @option{-Wall}.
+
@item -Wcast-qual
@opindex Wcast-qual
@opindex Wno-cast-qual
diagnosed and the warning is enabled by default. In C this warning is
enabled by @option{-Wall}.
+@item -Wenum-conversion @r{(C, Objective-C only)}
+@opindex Wenum-conversion
+@opindex Wno-enum-conversion
+Warn when a value of enumerated type is implicitly converted to a
+different enumerated type. This warning is enabled by @option{-Wextra}.
+
@item -Wextra-semi @r{(C++, Objective-C++ only)}
@opindex Wextra-semi
@opindex Wno-extra-semi
-ffinite-loops @gol
-fgcse -fgcse-lm @gol
-fhoist-adjacent-loads @gol
+-finline-functions @gol
-finline-small-functions @gol
-findirect-inlining @gol
-fipa-bit-cp -fipa-cp -fipa-icf @gol
@c Please keep the following list alphabetized!
@gccoptlist{-fgcse-after-reload @gol
--finline-functions @gol
-fipa-cp-clone
-floop-interchange @gol
-floop-unroll-and-jam @gol
Disregard strict standards compliance. @option{-Ofast} enables all
@option{-O3} optimizations. It also enables optimizations that are not
valid for all standard-compliant programs.
-It turns on @option{-ffast-math} and the Fortran-specific
-@option{-fstack-arrays}, unless @option{-fmax-stack-var-size} is
-specified, and @option{-fno-protect-parens}.
+It turns on @option{-ffast-math}, @option{-fallow-store-data-races}
+and the Fortran-specific @option{-fstack-arrays}, unless
+@option{-fmax-stack-var-size} is specified, and @option{-fno-protect-parens}.
@item -Og
@opindex Og
declared @code{static}, then the function is normally not output as
assembler code in its own right.
-Enabled at levels @option{-O3}, @option{-Os}. Also enabled
+Enabled at levels @option{-O2}, @option{-O3}, @option{-Os}. Also enabled
by @option{-fprofile-use} and @option{-fauto-profile}.
@item -finline-functions-called-once
Enabled at levels @option{-O2}, @option{-O3}.
+@item -fallow-store-data-races
+@opindex fallow-store-data-races
+Allow the compiler to introduce new data races on stores.
+
+Enabled at level @option{-Ofast}.
+
@item -funit-at-a-time
@opindex funit-at-a-time
This option is left for compatibility reasons. @option{-funit-at-a-time}
precedence; and for example @option{-ffp-contract=off} takes precedence
over @option{-ffp-contract=fast}. You can override them at link time.
+To enable debug info generation you need to supply @option{-g} at
+compile-time. If any of the input files at link time were built
+with debug info generation enabled the link will enable debug info
+generation as well. Any elaborate debug info settings
+like the dwarf level @option{-gdwarf-5} need to be explicitly repeated
+at the linker command line and mixing different settings in different
+translation units is discouraged.
+
If LTO encounters objects with C linkage declared with incompatible
types in separate translation units to be linked together (undefined
behavior according to ISO C99 6.2.7), a non-fatal diagnostic may be
double} variants, to generate code that raises the ``inexact''
floating-point exception for noninteger arguments. ISO C99 and C11
allow these functions to raise the ``inexact'' exception, but ISO/IEC
-TS 18661-1:2014, the C bindings to IEEE 754-2008, does not allow these
-functions to do so.
+TS 18661-1:2014, the C bindings to IEEE 754-2008, as integrated into
+ISO C2X, does not allow these functions to do so.
The default is @option{-ffp-int-builtin-inexact}, allowing the
-exception to be raised. This option does nothing unless
-@option{-ftrapping-math} is in effect.
+exception to be raised, unless C2X or a later C standard is selected.
+This option does nothing unless @option{-ftrapping-math} is in effect.
Even if @option{-fno-fp-int-builtin-inexact} is used, if the functions
generate a call to a library function then the ``inexact'' exception
link time. An example of such an optimization is relaxing calls to short call
instructions.
-@item -fbranch-target-load-optimize
-@opindex fbranch-target-load-optimize
-Perform branch target register load optimization before prologue / epilogue
-threading.
-The use of target registers can typically be exposed only during reload,
-thus hoisting loads out of loops and doing inter-block scheduling needs
-a separate optimization pass.
-
-@item -fbranch-target-load-optimize2
-@opindex fbranch-target-load-optimize2
-Perform branch target register load optimization after prologue / epilogue
-threading.
-
-@item -fbtr-bb-exclusive
-@opindex fbtr-bb-exclusive
-When performing branch target register load optimization, don't reuse
-branch target registers within any basic block.
-
@item -fstdarg-opt
@opindex fstdarg-opt
Optimize the prologue of variadic argument functions with respect to usage of
compilation time.
@item max-inline-insns-single
-Several parameters control the tree inliner used in GCC@.
-This number sets the maximum number of instructions (counted in GCC's
-internal representation) in a single function that the tree inliner
-considers for inlining. This only affects functions declared
-inline and methods implemented in a class declaration (C++).
+@item max-inline-insns-single-O2
+Several parameters control the tree inliner used in GCC@. This number sets the
+maximum number of instructions (counted in GCC's internal representation) in a
+single function that the tree inliner considers for inlining. This only
+affects functions declared inline and methods implemented in a class
+declaration (C++).
+
+For functions compiled with optimization levels
+@option{-O3} and @option{-Ofast} parameter @option{max-inline-insns-single} is
+applied. In other cases @option{max-inline-insns-single-O2} is applied.
+
@item max-inline-insns-auto
+@item max-inline-insns-auto-O2
When you use @option{-finline-functions} (included in @option{-O3}),
a lot of functions that would otherwise not be considered for inlining
by the compiler are investigated. To those functions, a different
(more restrictive) limit compared to functions declared inline can
be applied.
+For functions compiled with optimization levels
+@option{-O3} and @option{-Ofast} parameter @option{max-inline-insns-auto} is
+applied. In other cases @option{max-inline-insns-auto-O2} is applied.
+
@item max-inline-insns-small
This is bound applied to calls which are considered relevant with
@option{-finline-small-functions}.
Extra time accounted by inliner for function overhead such as time needed to
execute function prologue and epilogue
+@item inline-heuristics-hint-percent
+@item inline-heuristics-hint-percent-O2
+The scale (in percents) applied to @option{inline-insns-single},
+@option{inline-insns-single-O2}, @option{inline-insns-auto},
+@option{inline-insns-auto-O2} when inline heuristics hints that inlining is
+very profitable (will enable later optimizations).
+
+For functions compiled with optimization levels
+@option{-O3} and @option{-Ofast} parameter
+@option{inline-heuristics-hint-percent} is applied. In other cases
+@option{inline-heuristics-hint-percent-O2} is applied.
+
@item uninlined-thunk-insns
@item uninlined-thunk-time
Same as @option{--param uninlined-function-insns} and
@option{--param uninlined-function-time} but applied to function thunks
@item inline-min-speedup
+@item inline-min-speedup-O2
When estimated performance improvement of caller + callee runtime exceeds this
threshold (in percent), the function can be inlined regardless of the limit on
@option{--param max-inline-insns-single} and @option{--param
max-inline-insns-auto}.
+For functions compiled with optimization levels
+@option{-O3} and @option{-Ofast} parameter @option{inline-min-speedup} is
+applied. In other cases @option{inline-min-speedup-O2} is applied.
+
@item large-function-insns
The limit specifying really large functions. For functions larger than this
limit after inlining, inlining is constrained by
expressions whose probability exceeds the given threshold (in percents).
@item early-inlining-insns
+@item early-inlining-insns-O2
Specify growth that the early inliner can make. In effect it increases
the amount of inlining for code having a large abstraction penalty.
+For functions compiled with optimization levels
+@option{-O3} and @option{-Ofast} parameter @option{early-inlining-insns} is
+applied. In other cases @option{early-inlining-insns-O2} is applied.
+
@item max-early-inliner-iterations
Limit of iterations of the early inliner. This basically bounds
the number of nested indirect calls the early inliner can resolve.
@option{ipa-sra-ptr-growth-factor} times the size of the original
pointer parameter.
+@item ipa-sra-max-replacements
+Maximum pieces of an aggregate that IPA-SRA tracks. As a
+consequence, it is also the maximum number of replacements of a formal
+parameter.
+
@item sra-max-scalarization-size-Ospeed
@itemx sra-max-scalarization-size-Osize
The two Scalar Reduction of Aggregates passes (SRA and IPA-SRA) aim to
consider all memory clobbered after examining
@option{ipa-max-aa-steps} statements modifying memory.
+@item ipa-max-switch-predicate-bounds
+Maximal number of boundary endpoints of case ranges of switch statement.
+For switch exceeding this limit, IPA-CP will not construct cloning cost
+predicate, which is used to estimate cloning benefit, for default case
+of the switch statement.
+
+@item ipa-max-param-expr-ops
+IPA-CP will analyze conditional statement that references some function
+parameter to estimate benefit for cloning upon certain constant value.
+But if number of operations in a parameter expression exceeds
+@option{ipa-max-param-expr-ops}, the expression is treated as complicated
+one, and is not handled by IPA analysis.
+
@item lto-partitions
Specify desired number of partitions produced during WHOPR compilation.
The number of partitions should exceed the number of CPUs used for compilation.
if either vectorization (@option{-ftree-vectorize}) or if-conversion
(@option{-ftree-loop-if-convert}) is disabled.
-@item allow-store-data-races
-Allow optimizers to introduce new data races on stores.
-Set to 1 to allow, otherwise to 0.
-
@item case-values-threshold
The smallest number of different values for which it is best to use a
jump-table instead of a tree of conditional branches. If the value is
* C-SKY Options::
* Darwin Options::
* DEC Alpha Options::
+* eBPF Options::
* FR30 Options::
* FT32 Options::
* FRV Options::
* SH Options::
* Solaris 2 Options::
* SPARC Options::
-* SPU Options::
* System V Options::
* TILE-Gx Options::
* TILEPro Options::
@code{__builtin_speculation_safe_copy} to permit a more efficient code
sequence to be generated.
+@item -moutline-atomics
+@itemx -mno-outline-atomics
+Enable or disable calls to out-of-line helpers to implement atomic operations.
+These helpers will, at runtime, determine if the LSE instructions from
+ARMv8.1-A can be used; if not, they will use the load/store-exclusive
+instructions that are present in the base ARMv8.0 ISA.
+
+This option is only applicable when compiling for the base ARMv8.0
+instruction set. If using a later revision, e.g. @option{-march=armv8.1-a}
+or @option{-march=armv8-a+lse}, the ARMv8.1-Atomics instructions will be
+used directly. The same applies when using @option{-mcpu=} when the
+selected cpu supports the @samp{lse} feature.
+
@item -march=@var{name}
@opindex march
Specify the name of the target architecture and, optionally, one or
performance of the code. Permissible values for this option are:
@samp{generic}, @samp{cortex-a35}, @samp{cortex-a53}, @samp{cortex-a55},
@samp{cortex-a57}, @samp{cortex-a72}, @samp{cortex-a73}, @samp{cortex-a75},
-@samp{cortex-a76}, @samp{ares}, @samp{exynos-m1}, @samp{emag}, @samp{falkor},
+@samp{cortex-a76}, @samp{cortex-a76ae}, @samp{cortex-a77},
+@samp{cortex-a65}, @samp{cortex-a65ae}, @samp{cortex-a34},
+@samp{ares}, @samp{exynos-m1}, @samp{emag}, @samp{falkor},
@samp{neoverse-e1},@samp{neoverse-n1},@samp{qdf24xx}, @samp{saphira},
@samp{phecda}, @samp{xgene1}, @samp{vulcan}, @samp{octeontx},
@samp{octeontx81}, @samp{octeontx83}, @samp{thunderx}, @samp{thunderxt88},
@samp{cortex-a9}, @samp{cortex-a12}, @samp{cortex-a15}, @samp{cortex-a17},
@samp{cortex-a32}, @samp{cortex-a35}, @samp{cortex-a53}, @samp{cortex-a55},
@samp{cortex-a57}, @samp{cortex-a72}, @samp{cortex-a73}, @samp{cortex-a75},
-@samp{cortex-a76}, @samp{ares}, @samp{cortex-r4}, @samp{cortex-r4f},
+@samp{cortex-a76}, @samp{cortex-a76ae}, @samp{cortex-a77},
+@samp{ares}, @samp{cortex-r4}, @samp{cortex-r4f},
@samp{cortex-r5}, @samp{cortex-r7}, @samp{cortex-r8}, @samp{cortex-r52},
@samp{cortex-m0}, @samp{cortex-m0plus}, @samp{cortex-m1}, @samp{cortex-m3},
@samp{cortex-m4}, @samp{cortex-m7}, @samp{cortex-m23}, @samp{cortex-m33},
+@samp{cortex-m35p},
@samp{cortex-m1.small-multiply}, @samp{cortex-m0.small-multiply},
@samp{cortex-m0plus.small-multiply}, @samp{exynos-m1}, @samp{marvell-pj4},
@samp{neoverse-n1}, @samp{xscale}, @samp{iwmmxt}, @samp{iwmmxt2},
@table @samp
@item +nodsp
-Disable the DSP instructions on @samp{cortex-m33}.
+Disable the DSP instructions on @samp{cortex-m33}, @samp{cortex-m35p}.
@item +nofp
Disables the floating-point instructions on @samp{arm9e},
@samp{arm946e-s}, @samp{arm966e-s}, @samp{arm968e-s}, @samp{arm10e},
@samp{arm1020e}, @samp{arm1022e}, @samp{arm926ej-s},
@samp{arm1026ej-s}, @samp{cortex-r5}, @samp{cortex-r7}, @samp{cortex-r8},
-@samp{cortex-m4}, @samp{cortex-m7} and @samp{cortex-m33}.
+@samp{cortex-m4}, @samp{cortex-m7}, @samp{cortex-m33} and @samp{cortex-m35p}.
Disables the floating-point and SIMD instructions on
@samp{generic-armv7-a}, @samp{cortex-a5}, @samp{cortex-a7},
@samp{cortex-a8}, @samp{cortex-a9}, @samp{cortex-a12},
@item -mneon-for-64bits
@opindex mneon-for-64bits
-Enables using Neon to handle scalar 64-bits operations. This is
-disabled by default since the cost of moving data from core registers
-to Neon is high.
+This option is deprecated and has no effect.
@item -mslow-flash-data
@opindex mslow-flash-data
Generate secure code as per the "ARMv8-M Security Extensions: Requirements on
Development Tools Engineering Specification", which can be found on
@url{http://infocenter.arm.com/help/topic/com.arm.doc.ecm0359818/ECM0359818_armv8m_security_extensions_reqs_on_dev_tools_1_0.pdf}.
+
+@item -mfdpic
+@itemx -mno-fdpic
+@opindex mfdpic
+@opindex mno-fdpic
+Select the FDPIC ABI, which uses 64-bit function descriptors to
+represent pointers to functions. When the compiler is configured for
+@code{arm-*-uclinuxfdpiceabi} targets, this option is on by default
+and implies @option{-fPIE} if none of the PIC/PIE-related options is
+provided. On other targets, it only enables the FDPIC-specific code
+generation features, and the user should explicitly provide the
+PIC/PIE-related options as needed.
+
+Note that static linking is not supported because it would still
+involve the dynamic linker when the program self-relocates. If such
+behavior is acceptable, use -static and -Wl,-dynamic-linker options.
+
+The opposite @option{-mno-fdpic} option is useful (and required) to
+build the Linux kernel using the same (@code{arm-*-uclinuxfdpiceabi})
+toolchain as the one used to build the userland programs.
+
@end table
@node AVR Options
@end table
@end table
+@node eBPF Options
+@subsection eBPF Options
+@cindex eBPF Options
+
+@table @gcctabopt
+@item -mframe-limit=@var{bytes}
+This specifies the hard limit for frame sizes, in bytes. Currently,
+the value that can be specified should be less than or equal to
+@samp{32767}. Defaults to whatever limit is imposed by the version of
+the Linux kernel targeted.
+
+@item -mkernel=@var{version}
+@opindex mkernel
+This specifies the minimum version of the kernel that will run the
+compiled program. GCC uses this version to determine which
+instructions to use, what kernel helpers to allow, etc. Currently,
+@var{version} can be one of @samp{4.0}, @samp{4.1}, @samp{4.2},
+@samp{4.3}, @samp{4.4}, @samp{4.5}, @samp{4.6}, @samp{4.7},
+@samp{4.8}, @samp{4.9}, @samp{4.10}, @samp{4.11}, @samp{4.12},
+@samp{4.13}, @samp{4.14}, @samp{4.15}, @samp{4.16}, @samp{4.17},
+@samp{4.18}, @samp{4.19}, @samp{4.20}, @samp{5.0}, @samp{5.1},
+@samp{5.2}, @samp{latest} and @samp{native}.
+
+@item -mbig-endian
+@opindex mbig-endian
+Generate code for a big-endian target.
+
+@item -mlittle-endian
+@opindex mlittle-endian
+Generate code for a little-endian target. This is the default.
+@end table
+
@node FR30 Options
@subsection FR30 Options
@cindex FR30 Options
Otherwise, assume no such offset is present.
@end table
-@node SPU Options
-@subsection SPU Options
-@cindex SPU options
-
-These @samp{-m} options are supported on the SPU:
-
-@table @gcctabopt
-@item -mwarn-reloc
-@itemx -merror-reloc
-@opindex mwarn-reloc
-@opindex merror-reloc
-
-The loader for SPU does not handle dynamic relocations. By default, GCC
-gives an error when it generates code that requires a dynamic
-relocation. @option{-mno-error-reloc} disables the error,
-@option{-mwarn-reloc} generates a warning instead.
-
-@item -msafe-dma
-@itemx -munsafe-dma
-@opindex msafe-dma
-@opindex munsafe-dma
-
-Instructions that initiate or test completion of DMA must not be
-reordered with respect to loads and stores of the memory that is being
-accessed.
-With @option{-munsafe-dma} you must use the @code{volatile} keyword to protect
-memory accesses, but that can lead to inefficient code in places where the
-memory is known to not change. Rather than mark the memory as volatile,
-you can use @option{-msafe-dma} to tell the compiler to treat
-the DMA instructions as potentially affecting all memory.
-
-@item -mbranch-hints
-@opindex mbranch-hints
-
-By default, GCC generates a branch hint instruction to avoid
-pipeline stalls for always-taken or probably-taken branches. A hint
-is not generated closer than 8 instructions away from its branch.
-There is little reason to disable them, except for debugging purposes,
-or to make an object a little bit smaller.
-
-@item -msmall-mem
-@itemx -mlarge-mem
-@opindex msmall-mem
-@opindex mlarge-mem
-
-By default, GCC generates code assuming that addresses are never larger
-than 18 bits. With @option{-mlarge-mem} code is generated that assumes
-a full 32-bit address.
-
-@item -mstdmain
-@opindex mstdmain
-
-By default, GCC links against startup code that assumes the SPU-style
-main function interface (which has an unconventional parameter list).
-With @option{-mstdmain}, GCC links your program against startup
-code that assumes a C99-style interface to @code{main}, including a
-local copy of @code{argv} strings.
-
-@item -mfixed-range=@var{register-range}
-@opindex mfixed-range
-Generate code treating the given register range as fixed registers.
-A fixed register is one that the register allocator cannot use. This is
-useful when compiling kernel code. A register range is specified as
-two registers separated by a dash. Multiple register ranges can be
-specified separated by a comma.
-
-@item -mea32
-@itemx -mea64
-@opindex mea32
-@opindex mea64
-Compile code assuming that pointers to the PPU address space accessed
-via the @code{__ea} named address space qualifier are either 32 or 64
-bits wide. The default is 32 bits. As this is an ABI-changing option,
-all object code in an executable must be compiled with the same setting.
-
-@item -maddress-space-conversion
-@itemx -mno-address-space-conversion
-@opindex maddress-space-conversion
-@opindex mno-address-space-conversion
-Allow/disallow treating the @code{__ea} address space as superset
-of the generic address space. This enables explicit type casts
-between @code{__ea} and generic pointer as well as implicit
-conversions of generic pointers to @code{__ea} pointers. The
-default is to allow address space pointer conversions.
-
-@item -mcache-size=@var{cache-size}
-@opindex mcache-size
-This option controls the version of libgcc that the compiler links to an
-executable and selects a software-managed cache for accessing variables
-in the @code{__ea} address space with a particular cache size. Possible
-options for @var{cache-size} are @samp{8}, @samp{16}, @samp{32}, @samp{64}
-and @samp{128}. The default cache size is 64KB.
-
-@item -matomic-updates
-@itemx -mno-atomic-updates
-@opindex matomic-updates
-@opindex mno-atomic-updates
-This option controls the version of libgcc that the compiler links to an
-executable and selects whether atomic updates to the software-managed
-cache of PPU-side variables are used. If you use atomic updates, changes
-to a PPU variable from SPU code using the @code{__ea} named address space
-qualifier do not interfere with changes to other PPU variables residing
-in the same cache line from PPU code. If you do not use atomic updates,
-such interference may occur; however, writing back cache lines is
-more efficient. The default behavior is to use atomic updates.
-
-@item -mdual-nops
-@itemx -mdual-nops=@var{n}
-@opindex mdual-nops
-By default, GCC inserts NOPs to increase dual issue when it expects
-it to increase performance. @var{n} can be a value from 0 to 10. A
-smaller @var{n} inserts fewer NOPs. 10 is the default, 0 is the
-same as @option{-mno-dual-nops}. Disabled with @option{-Os}.
-
-@item -mhint-max-nops=@var{n}
-@opindex mhint-max-nops
-Maximum number of NOPs to insert for a branch hint. A branch hint must
-be at least 8 instructions away from the branch it is affecting. GCC
-inserts up to @var{n} NOPs to enforce this, otherwise it does not
-generate the branch hint.
-
-@item -mhint-max-distance=@var{n}
-@opindex mhint-max-distance
-The encoding of the branch hint instruction limits the hint to be within
-256 instructions of the branch it is affecting. By default, GCC makes
-sure it is within 125.
-
-@item -msafe-hints
-@opindex msafe-hints
-Work around a hardware bug that causes the SPU to stall indefinitely.
-By default, GCC inserts the @code{hbrp} instruction to make sure
-this stall won't happen.
-
-@end table
-
@node System V Options
@subsection Options for System V
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