Free Software Foundation, Inc.
Permission is granted to copy, distribute and/or modify this document
-under the terms of the GNU Free Documentation License, Version 1.2 or
+under the terms of the GNU Free Documentation License, Version 1.3 or
any later version published by the Free Software Foundation; with the
Invariant Sections being ``GNU General Public License'' and ``Funding
Free Software'', the Front-Cover texts being (a) (see below), and with
@gccoptlist{-c -S -E -o @var{file} -combine -no-canonical-prefixes @gol
-pipe -pass-exit-codes @gol
-x @var{language} -v -### --help@r{[}=@var{class}@r{[},@dots{}@r{]]} --target-help @gol
---version -wrapper@@@var{file} -fplugin=@var{file} -fplugin-arg-@var{name}=@var{arg}}
+--version -wrapper@@@var{file} -fplugin=@var{file} -fplugin-arg-@var{name}=@var{arg} @gol
+-fdump-ada-spec@r{[}-slim@r{]}}
@item C Language Options
@xref{C Dialect Options,,Options Controlling C Dialect}.
-fno-implicit-templates @gol
-fno-implicit-inline-templates @gol
-fno-implement-inlines -fms-extensions @gol
--fno-nonansi-builtins -fno-operator-names @gol
+-fno-nonansi-builtins -fnothrow-opt -fno-operator-names @gol
-fno-optional-diags -fpermissive @gol
-fno-pretty-templates @gol
-frepo -fno-rtti -fstats -ftemplate-depth=@var{n} @gol
-Wlogical-op -Wlong-long @gol
-Wmain -Wmissing-braces -Wmissing-field-initializers @gol
-Wmissing-format-attribute -Wmissing-include-dirs @gol
--Wmissing-noreturn -Wno-mudflap @gol
+-Wno-mudflap @gol
-Wno-multichar -Wnonnull -Wno-overflow @gol
-Woverlength-strings -Wpacked -Wpacked-bitfield-compat -Wpadded @gol
-Wparentheses -Wpedantic-ms-format -Wno-pedantic-ms-format @gol
-Wsign-compare -Wsign-conversion -Wstack-protector @gol
-Wstrict-aliasing -Wstrict-aliasing=n @gol
-Wstrict-overflow -Wstrict-overflow=@var{n} @gol
+-Wsuggest-attribute=@r{[}const@r{|}pure@r{]} @gol
-Wswitch -Wswitch-default -Wswitch-enum -Wsync-nand @gol
-Wsystem-headers -Wtrigraphs -Wtype-limits -Wundef -Wuninitialized @gol
-Wunknown-pragmas -Wno-pragmas @gol
-fgcse-sm -fif-conversion -fif-conversion2 -findirect-inlining @gol
-finline-functions -finline-functions-called-once -finline-limit=@var{n} @gol
-finline-small-functions -fipa-cp -fipa-cp-clone -fipa-matrix-reorg -fipa-pta @gol
--fipa-pure-const -fipa-reference -fipa-struct-reorg @gol
--fipa-type-escape -fira-algorithm=@var{algorithm} @gol
+-fipa-profile -fipa-pure-const -fipa-reference -fipa-struct-reorg @gol
+-fira-algorithm=@var{algorithm} @gol
-fira-region=@var{region} -fira-coalesce @gol
-fira-loop-pressure -fno-ira-share-save-slots @gol
-fno-ira-share-spill-slots -fira-verbose=@var{n} @gol
-funit-at-a-time -funroll-all-loops -funroll-loops @gol
-funsafe-loop-optimizations -funsafe-math-optimizations -funswitch-loops @gol
-fvariable-expansion-in-unroller -fvect-cost-model -fvpt -fweb @gol
--fwhole-program -fwhopr -fwpa -fuse-linker-plugin @gol
+-fwhole-program -fwhopr[=@var{n}] -fwpa -fuse-linker-plugin @gol
--param @var{name}=@var{value}
--O -O0 -O1 -O2 -O3 -Os}
+-O -O0 -O1 -O2 -O3 -Os -Ofast}
@item Preprocessor Options
@xref{Preprocessor Options,,Options Controlling the Preprocessor}.
@item Directory Options
@xref{Directory Options,,Options for Directory Search}.
-@gccoptlist{-B@var{prefix} -I@var{dir} -iquote@var{dir} -L@var{dir}
--specs=@var{file} -I- --sysroot=@var{dir}}
+@gccoptlist{-B@var{prefix} -I@var{dir} -iplugindir=@var{dir}}
+-iquote@var{dir} -L@var{dir} -specs=@var{file} -I-
+--sysroot=@var{dir}
@item Machine Dependent Options
@xref{Submodel Options,,Hardware Models and Configurations}.
-mcpu=@var{cpu}}
@emph{GNU/Linux Options}
-@gccoptlist{-muclibc}
+@gccoptlist{-mglibc -muclibc -mbionic -mandroid @gol
+-tno-android-cc -tno-android-ld}
@emph{H8/300 Options}
@gccoptlist{-mrelax -mh -ms -mn -mint32 -malign-300}
@emph{RS/6000 and PowerPC Options}
@gccoptlist{-mcpu=@var{cpu-type} @gol
-mtune=@var{cpu-type} @gol
+-mcmodel=@var{code-model} @gol
-mpower -mno-power -mpower2 -mno-power2 @gol
-mpowerpc -mpowerpc64 -mno-powerpc @gol
-maltivec -mno-altivec @gol
-mfloat-gprs=yes -mfloat-gprs=no -mfloat-gprs=single -mfloat-gprs=double @gol
-mprototype -mno-prototype @gol
-msim -mmvme -mads -myellowknife -memb -msdata @gol
--msdata=@var{opt} -mvxworks -G @var{num} -pthread}
+-msdata=@var{opt} -mvxworks -G @var{num} -pthread @gol
+-mrecip -mrecip=@var{opt} -mno-recip -mrecip-precision -mno-recip-precision}
@emph{RX Options}
@gccoptlist{-m64bit-doubles -m32bit-doubles -fpu -nofpu@gol
-mprefergot -musermode -multcost=@var{number} -mdiv=@var{strategy} @gol
-mdivsi3_libfunc=@var{name} -mfixed-range=@var{register-range} @gol
-madjust-unroll -mindexed-addressing -mgettrcost=@var{number} -mpt-fixed @gol
--minvalid-symbols}
+-maccumulate-outgoing-args -minvalid-symbols}
@emph{SPARC Options}
@gccoptlist{-mcpu=@var{cpu-type} @gol
@emph{Xtensa Options}
@gccoptlist{-mconst16 -mno-const16 @gol
-mfused-madd -mno-fused-madd @gol
+-mforce-no-pic @gol
-mserialize-volatile -mno-serialize-volatile @gol
-mtext-section-literals -mno-text-section-literals @gol
-mtarget-align -mno-target-align @gol
@item @var{file}.h
C, C++, Objective-C or Objective-C++ header file to be turned into a
-precompiled header.
+precompiled header (default), or C, C++ header file to be turned into an
+Ada spec (via the @option{-fdump-ada-spec} switch).
@item @var{file}.cc
@itemx @var{file}.cp
@itemx @var{file}.HPP
@itemx @var{file}.h++
@itemx @var{file}.tcc
-C++ header file to be turned into a precompiled header.
+C++ header file to be turned into a precompiled header or Ada spec.
@item @var{file}.f
@itemx @var{file}.for
@item -###
@opindex ###
-Like @option{-v} except the commands are not executed and all command
-arguments are quoted. This is useful for shell scripts to capture the
-driver-generated command lines.
+Like @option{-v} except the commands are not executed and arguments
+are quoted unless they contain only alphanumeric characters or @code{./-_}.
+This is useful for shell scripts to capture the driver-generated command lines.
@item -pipe
@opindex pipe
Define an argument called @var{key} with a value of @var{value}
for the plugin called @var{name}.
+@item -fdump-ada-spec@r{[}-slim@r{]}
+For C and C++ source and include files, generate corresponding Ada
+specs. @xref{Generating Ada Bindings for C and C++ headers,,, gnat_ugn,
+GNAT User's Guide}, which provides detailed documentation on this feature.
+
@include @value{srcdir}/../libiberty/at-file.texi
@end table
@w{@uref{http://gcc.gnu.org/c99status.html}} for more information. The
names @samp{c9x} and @samp{iso9899:199x} are deprecated.
+@item c1x
+ISO C1X, the draft of the next revision of the ISO C standard.
+Support is limited and experimental and features enabled by this
+option may be changed or removed if changed in or removed from the
+standard draft.
+
@item gnu90
@itemx gnu89
GNU dialect of ISO C90 (including some C99 features). This
GNU dialect of ISO C99. When ISO C99 is fully implemented in GCC,
this will become the default. The name @samp{gnu9x} is deprecated.
+@item gnu1x
+GNU dialect of ISO C1X. Support is limited and experimental and
+features enabled by this option may be changed or removed if changed
+in or removed from the standard draft.
+
@item c++98
The 1998 ISO C++ standard plus amendments. Same as @option{-ansi} for
C++ code.
ANSI/ISO C@. These include @code{ffs}, @code{alloca}, @code{_exit},
@code{index}, @code{bzero}, @code{conjf}, and other related functions.
+@item -fnothrow-opt
+@opindex fnothrow-opt
+Treat a @code{throw()} exception specification as though it were a
+@code{noexcept} specification to reduce or eliminate the text size
+overhead relative to a function with no exception specification. If
+the function has local variables of types with non-trivial
+destructors, the exception specification will actually make the
+function smaller because the EH cleanups for those variables can be
+optimized away. The semantic effect is that an exception thrown out of
+a function with such an exception specification will result in a call
+to @code{terminate} rather than @code{unexpected}.
+
@item -fno-operator-names
@opindex fno-operator-names
Do not treat the operator name keywords @code{and}, @code{bitand},
Emit statistics about front-end processing at the end of the compilation.
This information is generally only useful to the G++ development team.
+@item -fstrict-enums
+@opindex fstrict-enums
+Allow the compiler to optimize using the assumption that a value of
+enumeration type can only be one of the values of the enumeration (as
+defined in the C++ standard; basically, a value which can be
+represented in the minimum number of bits needed to represent all the
+enumerators). This assumption may not be valid if the program uses a
+cast to convert an arbitrary integer value to the enumeration type.
+
@item -ftemplate-depth=@var{n}
@opindex ftemplate-depth
Set the maximum instantiation depth for template classes to @var{n}.
If a source file was changed between @option{-fprofile-gen} and
@option{-fprofile-use}, the files with the profile feedback can fail
to match the source file and GCC can not use the profile feedback
-information. By default, GCC emits an error message in this case.
-The option @option{-Wcoverage-mismatch} emits a warning instead of an
-error. GCC does not use appropriate feedback profiles, so using this
-option can result in poorly optimized code. This option is useful
-only in the case of very minor changes such as bug fixes to an
-existing code-base.
+information. By default, this warning is enabled and is treated as an
+error. @option{-Wno-coverage-mismatch} can be used to disable the
+warning or @option{-Wno-error=coverage-mismatch} can be used to
+disable the error. Disable the error for this warning can result in
+poorly optimized code, so disabling the error is useful only in the
+case of very minor changes such as bug fixes to an existing code-base.
+Completely disabling the warning is not recommended.
@end table
language-specific options also refer to @ref{C++ Dialect Options} and
@ref{Objective-C and Objective-C++ Dialect Options}.
+When an unrecognized warning label is requested (e.g.,
+@option{-Wunknown-warning}), GCC will emit a diagnostic stating
+that the option is not recognized. However, if the @samp{-Wno-} form
+is used, the behavior is slightly different: No diagnostic will be
+produced for @option{-Wno-unknown-warning} unless other diagnostics
+are being produced. This allows the use of new @option{-Wno-} options
+with old compilers, but if something goes wrong, the compiler will
+warn that an unrecognized option was used.
+
@table @gcctabopt
@item -pedantic
@opindex pedantic
-Wc++0x-compat @gol
-Wchar-subscripts @gol
-Wenum-compare @r{(in C/Objc; this is on by default in C++)} @gol
--Wimplicit-int @gol
--Wimplicit-function-declaration @gol
+-Wimplicit-int @r{(C and Objective-C only)} @gol
+-Wimplicit-function-declaration @r{(C and Objective-C only)} @gol
-Wcomment @gol
-Wformat @gol
-Wmain @r{(only for C/ObjC and unless} @option{-ffreestanding}@r{)} @gol
@option{-pedantic-errors}. This warning is also enabled by
@option{-Wall}.
-@item -Wimplicit
+@item -Wimplicit @r{(C and Objective-C only)}
@opindex Wimplicit
@opindex Wno-implicit
Same as @option{-Wimplicit-int} and @option{-Wimplicit-function-declaration}.
false positives.
@end table
+@item -Wsuggest-attribute=@r{[}const@r{|}pure@r{]}
+@opindex Wsuggest-attribute=
+@opindex Wno-suggest-attribute=
+Warn for cases where adding an attribute may be beneficial. The
+attributes currently supported are listed below.
+
+@table @gcctabopt
+@item -Wsuggest-attribute=pure
+@itemx -Wsuggest-attribute=const
+@opindex Wsuggest-attribute=pure
+@opindex Wno-suggest-attribute=pure
+@opindex Wsuggest-attribute=const
+@opindex Wno-suggest-attribute=const
+@opindex Wsuggest-attribute=noreturn
+@opindex Wno-suggest-attribute=noreturn
+
+Warn about functions which might be candidates for attributes
+@code{pure}, @code{const} or @code{noreturn}. The compiler only warns for
+functions visible in other compilation units or (in the case of @code{pure} and
+@code{const}) if it cannot prove that the function returns normally. A function
+returns normally if it doesn't contain an infinite loop nor returns abnormally
+by throwing, calling @code{abort()} or trapping. This analysis requires option
+@option{-fipa-pure-const}, which is enabled by default at @option{-O} and
+higher. Higher optimization levels improve the accuracy of the analysis.
+@end table
+
@item -Warray-bounds
@opindex Wno-array-bounds
@opindex Warray-bounds
This option is only active when @option{-ftree-vrp} is active
-(default for -O2 and above). It warns about subscripts to arrays
+(default for @option{-O2} and above). It warns about subscripts to arrays
that are always out of bounds. This warning is enabled by @option{-Wall}.
@item -Wno-div-by-zero
This warning is included in @option{-Wextra}. To get other @option{-Wextra}
warnings without this one, use @samp{-Wextra -Wno-missing-field-initializers}.
-@item -Wmissing-noreturn
-@opindex Wmissing-noreturn
-@opindex Wno-missing-noreturn
-Warn about functions which might be candidates for attribute @code{noreturn}.
-Note these are only possible candidates, not absolute ones. Care should
-be taken to manually verify functions actually do not ever return before
-adding the @code{noreturn} attribute, otherwise subtle code generation
-bugs could be introduced. You will not get a warning for @code{main} in
-hosted C environments.
-
@item -Wmissing-format-attribute
@opindex Wmissing-format-attribute
@opindex Wno-missing-format-attribute
The restrictions on @samp{offsetof} may be relaxed in a future version
of the C++ standard.
-@item -Wno-int-to-pointer-cast @r{(C and Objective-C only)}
+@item -Wno-int-to-pointer-cast
@opindex Wno-int-to-pointer-cast
@opindex Wint-to-pointer-cast
Suppress warnings from casts to pointer type of an integer of a
-different size.
+different size. In C++, casting to a pointer type of smaller size is
+an error. @option{Wint-to-pointer-cast} is enabled by default.
+
@item -Wno-pointer-to-int-cast @r{(C and Objective-C only)}
@opindex Wno-pointer-to-int-cast
-fif-conversion2 @gol
-fif-conversion @gol
-fipa-pure-const @gol
+-fipa-profile @gol
-fipa-reference @gol
-fmerge-constants
-fsplit-wide-types @gol
-falign-labels -freorder-blocks -freorder-blocks-and-partition @gol
-fprefetch-loop-arrays -ftree-vect-loop-version}
+@item -Ofast
+@opindex Ofast
+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}.
+
If you use multiple @option{-O} options, with or without level numbers,
the last such option is the one that is effective.
@end table
layout in order to better utilize spatial locality. This transformation is
affective for programs containing arrays of structures. Available in two
compilation modes: profile-based (enabled with @option{-fprofile-generate})
-or static (which uses built-in heuristics). Require @option{-fipa-type-escape}
-to provide the safety of this transformation. It works only in whole program
+or static (which uses built-in heuristics). It works only in whole program
mode, so it requires @option{-fwhole-program} and @option{-combine} to be
enabled. Structures considered @samp{cold} by this transformation are not
affected (see @option{--param struct-reorg-cold-struct-ratio=@var{value}}).
@item -fipa-pta
@opindex fipa-pta
-Perform interprocedural pointer analysis. This option is experimental
-and does not affect generated code.
+Perform interprocedural pointer analysis and interprocedural modification
+and reference analysis. This option can cause excessive memory and
+compile-time usage on large compilation units. It is not enabled by
+default at any optimization level.
+
+@item -fipa-profile
+@opindex fipa-profile
+Perform interprocedural profile propagation. The functions called only from
+cold functions are marked as cold. Also functions executed once (such as
+@code{cold}, @code{noreturn}, static constructors or destructors) are identified. Cold
+functions and loop less parts of functions executed once are then optimized for
+size.
+Enabled by default at @option{-O} and higher.
@item -fipa-cp
@opindex fipa-cp
This option is disabled by default.
-@item -fwhopr
+@item -fwhopr[=@var{n}]
@opindex fwhopr
This option is identical in functionality to @option{-flto} but it
differs in how the final link stage is executed. Instead of loading
that otherwise would not fit in memory. This option enables
@option{-fwpa} and @option{-fltrans} automatically.
-Disabled by default.
+If you specify the optional @var{n} the link stage is executed in
+parallel using @var{n} parallel jobs by utilizing an installed
+@command{make} program. The environment variable @env{MAKE} may be
+used to override the program used.
-This option is experimental.
+Disabled by default.
@item -fwpa
@opindex fwpa
@item min-insn-to-prefetch-ratio
The minimum ratio between the number of instructions and the
-number of prefetches to enable prefetching in a loop with an
-unknown trip count.
+number of prefetches to enable prefetching in a loop.
@item prefetch-min-insn-to-mem-ratio
The minimum ratio between the number of instructions and the
If you really need to change the search order for system directories,
use the @option{-nostdinc} and/or @option{-isystem} options.
+@item -iplugindir=@var{dir}
+Set the directory to search for plugins which are passed
+by @option{-fplugin=@var{name}} instead of
+@option{-fplugin=@var{path}/@var{name}.so}. This option is not meant
+to be used by the user, but only passed by the driver.
+
@item -iquote@var{dir}
@opindex iquote
Add the directory @var{dir} to the head of the list of directories to
by default. This can be overridden with the @code{section} attribute.
@xref{Variable Attributes}.
-@item -mfix-cortex-m3-ldrd
-@opindex mfix-cortex-m3-ldrd
-Some Cortex-M3 cores can cause data corruption when @code{ldrd} instructions
-with overlapping destination and base registers are used. This option avoids
-generating these instructions. This option is enabled by default when
-@option{-mcpu=cortex-m3} is specified.
-
@end table
@node ARM Options
@samp{arm1136j-s}, @samp{arm1136jf-s}, @samp{mpcore}, @samp{mpcorenovfp},
@samp{arm1156t2-s}, @samp{arm1156t2f-s}, @samp{arm1176jz-s}, @samp{arm1176jzf-s},
@samp{cortex-a5}, @samp{cortex-a8}, @samp{cortex-a9},
-@samp{cortex-r4}, @samp{cortex-r4f}, @samp{cortex-m3},
+@samp{cortex-r4}, @samp{cortex-r4f}, @samp{cortex-m4}, @samp{cortex-m3},
@samp{cortex-m1},
@samp{cortex-m0},
@samp{xscale}, @samp{iwmmxt}, @samp{iwmmxt2}, @samp{ep9312}.
loader imposes this restriction, and when @option{-fpic} or @option{-fPIC}
is specified.
+@item -mfix-cortex-m3-ldrd
+@opindex mfix-cortex-m3-ldrd
+Some Cortex-M3 cores can cause data corruption when @code{ldrd} instructions
+with overlapping destination and base registers are used. This option avoids
+generating these instructions. This option is enabled by default when
+@option{-mcpu=cortex-m3} is specified.
+
@end table
@node AVR Options
@table @gcctabopt
@item -mglibc
@opindex mglibc
-Use the GNU C library instead of uClibc. This is the default except
-on @samp{*-*-linux-*uclibc*} targets.
+Use the GNU C library. This is the default except
+on @samp{*-*-linux-*uclibc*} and @samp{*-*-linux-*android*} targets.
@item -muclibc
@opindex muclibc
-Use uClibc instead of the GNU C library. This is the default on
+Use uClibc C library. This is the default on
@samp{*-*-linux-*uclibc*} targets.
+
+@item -mbionic
+@opindex mbionic
+Use Bionic C library. This is the default on
+@samp{*-*-linux-*android*} targets.
+
+@item -mandroid
+@opindex mandroid
+Compile code compatible with Android platform. This is the default on
+@samp{*-*-linux-*android*} targets.
+
+When compiling, this option enables @option{-mbionic}, @option{-fPIC},
+@option{-fno-exceptions} and @option{-fno-rtti} by default. When linking,
+this option makes the GCC driver pass Android-specific options to the linker.
+Finally, this option causes the preprocessor macro @code{__ANDROID__}
+to be defined.
+
+@item -tno-android-cc
+@opindex tno-android-cc
+Disable compilation effects of @option{-mandroid}, i.e., do not enable
+@option{-mbionic}, @option{-fPIC}, @option{-fno-exceptions} and
+@option{-fno-rtti} by default.
+
+@item -tno-android-ld
+@opindex tno-android-ld
+Disable linking effects of @option{-mandroid}, i.e., pass standard Linux
+linking options to the linker.
+
@end table
@node H8/300 Options
architecture, registers, and mnemonics set by @option{-mcpu}, but the
scheduling parameters set by @option{-mtune}.
-@item -mswdiv
-@itemx -mno-swdiv
-@opindex mswdiv
-@opindex mno-swdiv
-Generate code to compute division as reciprocal estimate and iterative
-refinement, creating opportunities for increased throughput. This
-feature requires: optional PowerPC Graphics instruction set for single
-precision and FRE instruction for double precision, assuming divides
-cannot generate user-visible traps, and the domain values not include
-Infinities, denormals or zero denominator.
+@item -mcmodel=small
+@opindex mcmodel=small
+Generate PowerPC64 code for the small model: The TOC is limited to
+64k.
+
+@item -mcmodel=medium
+@opindex mcmodel=medium
+Generate PowerPC64 code for the medium model: The TOC and other static
+data may be up to a total of 4G in size.
+
+@item -mcmodel=large
+@opindex mcmodel=large
+Generate PowerPC64 code for the large model: The TOC may be up to 4G
+in size. Other data and code is only limited by the 64-bit address
+space.
@item -maltivec
@itemx -mno-altivec
Adds support for multithreading with the @dfn{pthreads} library.
This option sets flags for both the preprocessor and linker.
+@item -mrecip
+@itemx -mno-recip
+@opindex mrecip
+This option will enable GCC to use the reciprocal estimate and
+reciprocal square root estimate instructions with additional
+Newton-Raphson steps to increase precision instead of doing a divide or
+square root and divide for floating point arguments. You should use
+the @option{-ffast-math} option when using @option{-mrecip} (or at
+least @option{-funsafe-math-optimizations},
+@option{-finite-math-only}, @option{-freciprocal-math} and
+@option{-fno-trapping-math}). Note that while the throughput of the
+sequence is generally higher than the throughput of the non-reciprocal
+instruction, the precision of the sequence can be decreased by up to 2
+ulp (i.e. the inverse of 1.0 equals 0.99999994) for reciprocal square
+roots.
+
+@item -mrecip=@var{opt}
+@opindex mrecip=opt
+This option allows to control which reciprocal estimate instructions
+may be used. @var{opt} is a comma separated list of options, that may
+be preceeded by a @code{!} to invert the option:
+@code{all}: enable all estimate instructions,
+@code{default}: enable the default instructions, equvalent to @option{-mrecip},
+@code{none}: disable all estimate instructions, equivalent to @option{-mno-recip};
+@code{div}: enable the reciprocal approximation instructions for both single and double precision;
+@code{divf}: enable the single precision reciprocal approximation instructions;
+@code{divd}: enable the double precision reciprocal approximation instructions;
+@code{rsqrt}: enable the reciprocal square root approximation instructions for both single and double precision;
+@code{rsqrtf}: enable the single precision reciprocal square root approximation instructions;
+@code{rsqrtd}: enable the double precision reciprocal square root approximation instructions;
+
+So for example, @option{-mrecip=all,!rsqrtd} would enable the
+all of the reciprocal estimate instructions, except for the
+@code{FRSQRTE}, @code{XSRSQRTEDP}, and @code{XVRSQRTEDP} instructions
+which handle the double precision reciprocal square root calculations.
+
+@item -mrecip-precision
+@itemx -mno-recip-precision
+@opindex mrecip-precision
+Assume (do not assume) that the reciprocal estimate instructions
+provide higher precision estimates than is mandated by the powerpc
+ABI. Selecting @option{-mcpu=power6} or @option{-mcpu=power7}
+automatically selects @option{-mrecip-precision}. The double
+precision square root estimate instructions are not generated by
+default on low precision machines, since they do not provide an
+estimate that converges after three steps.
@end table
@node RX Options
slows down the case of larger dividends. inv20u assumes the case of a such
a small dividend to be unlikely, and inv20l assumes it to be likely.
+@item -maccumulate-outgoing-args
+@opindex maccumulate-outgoing-args
+Reserve space once for outgoing arguments in the function prologue rather
+than around each call. Generally beneficial for performance and size. Also
+needed for unwinding to avoid changing the stack frame around conditional code.
+
@item -mdivsi3_libfunc=@var{name}
@opindex mdivsi3_libfunc=@var{name}
Set the name of the library function used for 32 bit signed division to
The default is @option{-mserialize-volatile}. Use
@option{-mno-serialize-volatile} to omit the @code{MEMW} instructions.
+@item -mforce-no-pic
+@opindex mforce-no-pic
+For targets, like GNU/Linux, where all user-mode Xtensa code must be
+position-independent code (PIC), this option disables PIC for compiling
+kernel code.
+
@item -mtext-section-literals
@itemx -mno-text-section-literals
@opindex mtext-section-literals
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