@c man begin COPYRIGHT
Copyright @copyright{} 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
-1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006 Free Software Foundation, Inc.
+1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006,
+2007 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
@c man end
@c man begin BUGS
For instructions on reporting bugs, see
-@w{@uref{http://gcc.gnu.org/bugs.html}}.
+@w{@value{BUGURL}}.
@c man end
@c man begin AUTHOR
See the Info entry for @command{gcc}, or
-fgcse -fgcse-lm -fgcse-sm -fgcse-las -fgcse-after-reload @gol
-fcrossjumping -fif-conversion -fif-conversion2 @gol
-finline-functions -finline-functions-called-once @gol
--finline-limit=@var{n} -fkeep-inline-functions @gol
+-finline-small-functions -finline-limit=@var{n} -fkeep-inline-functions @gol
-fkeep-static-consts -fmerge-constants -fmerge-all-constants @gol
-fmodulo-sched -fmodulo-sched-allow-regmoves -fno-branch-count-reg @gol
-fno-default-inline -fno-defer-pop -fmove-loop-invariants @gol
-fvariable-expansion-in-unroller -ftree-reassoc @gol
-ftree-pre -ftree-ccp -ftree-dce -ftree-loop-optimize @gol
-ftree-loop-linear -ftree-loop-im -ftree-loop-ivcanon -fivopts @gol
--fcheck-data-deps @gol
+-fcheck-data-deps -ftree-parallelize-loops @gol
-ftree-dominator-opts -ftree-dse -ftree-copyrename -ftree-sink @gol
-ftree-ch -ftree-sra -ftree-ter -ftree-fre -ftree-vectorize @gol
-ftree-vect-loop-version -fvect-cost-model -ftree-salias -fipa-pta -fweb @gol
-mcall-prologues -mno-tablejump -mtiny-stack -mint8}
@emph{Blackfin Options}
-@gccoptlist{-mcpu=@var{cpu} -msim -momit-leaf-frame-pointer @gol
--mno-omit-leaf-frame-pointer -mspecld-anomaly -mno-specld-anomaly @gol
--mcsync-anomaly -mno-csync-anomaly -mlow-64k -mno-low64k @gol
--mstack-check-l1 -mid-shared-library -mno-id-shared-library @gol
--mshared-library-id=@var{n} -mleaf-id-shared-library @gol
--mno-leaf-id-shared-library -msep-data -mno-sep-data -mlong-calls @gol
--mno-long-calls}
+@gccoptlist{-mcpu=@var{cpu}@r{[}-@var{sirevision}@r{]} @gol
+-msim -momit-leaf-frame-pointer -mno-omit-leaf-frame-pointer @gol
+-mspecld-anomaly -mno-specld-anomaly -mcsync-anomaly -mno-csync-anomaly @gol
+-mlow-64k -mno-low64k -mstack-check-l1 -mid-shared-library @gol
+-mno-id-shared-library -mshared-library-id=@var{n} @gol
+-mleaf-id-shared-library -mno-leaf-id-shared-library @gol
+-msep-data -mno-sep-data -mlong-calls -mno-long-calls @gol
+-mfast-fp -minline-plt}
@emph{CRIS Options}
@gccoptlist{-mcpu=@var{cpu} -march=@var{cpu} -mtune=@var{cpu} @gol
-mno-wide-multiply -mrtd -malign-double @gol
-mpreferred-stack-boundary=@var{num} -mcx16 -msahf -mrecip @gol
-mmmx -msse -msse2 -msse3 -mssse3 -msse4.1 -msse4.2 -msse4 @gol
--msse4a -m3dnow -mpopcnt -mabm @gol
+-msse4a -m3dnow -mpopcnt -mabm -msse5 @gol
-mthreads -mno-align-stringops -minline-all-stringops @gol
-mpush-args -maccumulate-outgoing-args -m128bit-long-double @gol
-m96bit-long-double -mregparm=@var{num} -msseregparm @gol
--mpc32 -mpc64 -mpc80 mstackrealign @gol
+-mveclibabi=@var{type} -mpc32 -mpc64 -mpc80 -mstackrealign @gol
-momit-leaf-frame-pointer -mno-red-zone -mno-tls-direct-seg-refs @gol
-mcmodel=@var{code-model} @gol
--m32 -m64 -mlarge-data-threshold=@var{num}}
+-m32 -m64 -mlarge-data-threshold=@var{num} @gol
+-mfused-madd -mno-fused-madd}
@emph{IA-64 Options}
@gccoptlist{-mbig-endian -mlittle-endian -mgnu-as -mgnu-ld -mno-pic @gol
@emph{MIPS Options}
@gccoptlist{-EL -EB -march=@var{arch} -mtune=@var{arch} @gol
-mips1 -mips2 -mips3 -mips4 -mips32 -mips32r2 -mips64 @gol
--mips16 -mno-mips16 -mabi=@var{abi} -mabicalls -mno-abicalls @gol
+-mips16 -mno-mips16 -mflip-mips16 @gol
+-minterlink-mips16 -mno-interlink-mips16 @gol
+-mabi=@var{abi} -mabicalls -mno-abicalls @gol
-mshared -mno-shared -mxgot -mno-xgot -mgp32 -mgp64 @gol
-mfp32 -mfp64 -mhard-float -msoft-float @gol
-msingle-float -mdouble-float -mdsp -mno-dsp -mdspr2 -mno-dspr2 @gol
-msmartmips -mno-smartmips @gol
-mpaired-single -mno-paired-single -mdmx -mno-mdmx @gol
--mips3d -mno-mips3d -mmt -mno-mt @gol
+-mips3d -mno-mips3d -mmt -mno-mt -mllsc -mno-llsc @gol
-mlong64 -mlong32 -msym32 -mno-sym32 @gol
--G@var{num} -membedded-data -mno-embedded-data @gol
+-G@var{num} -mlocal-sdata -mno-local-sdata @gol
+-mextern-sdata -mno-extern-sdata -mgpopt -mno-gopt @gol
+-membedded-data -mno-embedded-data @gol
-muninit-const-in-rodata -mno-uninit-const-in-rodata @gol
-mcode-readable=@var{setting} @gol
-msplit-addresses -mno-split-addresses @gol
-misel=yes -misel=no @gol
-mspe -mno-spe @gol
-mspe=yes -mspe=no @gol
+-mpaired @gol
-mvrsave -mno-vrsave @gol
-mmulhw -mno-mulhw @gol
-mdlmzb -mno-dlmzb @gol
Assembler code.
@item @var{file}.S
+@itemx @var{file}.sx
Assembler code which must be preprocessed.
@item @var{other}
@item -Wnon-virtual-dtor @r{(C++ only)}
@opindex Wnon-virtual-dtor
-Warn when a class appears to be polymorphic, thereby requiring a virtual
-destructor, yet it declares a non-virtual one. This warning is also
-enabled if -Weffc++ is specified.
+Warn when a class has virtual functions and accessible non-virtual
+destructor, in which case it would be possible but unsafe to delete
+an instance of a derived class through a pointer to the base class.
+This warning is also enabled if -Weffc++ is specified.
@item -Wreorder @r{(C++ only)}
@opindex Wreorder
@opindex w
Inhibit all warning messages.
+@item -Wall
+@opindex Wall
+This enables all the warnings about constructions that some users
+consider questionable, and that are easy to avoid (or modify to
+prevent the warning), even in conjunction with macros. This also
+enables some language-specific warnings described in @ref{C++ Dialect
+Options} and @ref{Objective-C and Objective-C++ Dialect Options}.
+
+@option{-Wall} turns on the following warning flags:
+
+@gccoptlist{-Waddress @gol
+-Warray-bounds @r{(only with} @option{-O2}@r{)} @gol
+-Wc++0x-compat @gol
+-Wchar-subscripts @gol
+-Wimplicit-int @gol
+-Wimplicit-function-declaration @gol
+-Wcomment @gol
+-Wformat @gol
+-Wmain @r{(only for C/ObjC and unless} @option{-ffreestanding}@r{)} @gol
+-Wmissing-braces @gol
+-Wnonnull @gol
+-Wparentheses @gol
+-Wpointer-sign @gol
+-Wreorder @gol
+-Wreturn-type @gol
+-Wsequence-point @gol
+-Wsign-compare @r{(only in C++)} @gol
+-Wstrict-aliasing @gol
+-Wstrict-overflow @gol
+-Wswitch @gol
+-Wtrigraphs @gol
+-Wuninitialized @r{(only with} @option{-O1}@r{,} @option{-O2} @r{or} @option{-O3}@r{)} @gol
+-Wunknown-pragmas @gol
+-Wunused-function @gol
+-Wunused-label @gol
+-Wunused-value @gol
+-Wunused-variable @gol
+}
+
@item -Wno-import
@opindex Wno-import
Inhibit warning messages about the use of @samp{#import}.
compiler is using for optimization. The warning does not catch all
cases, but does attempt to catch the more common pitfalls. It is
included in @option{-Wall}.
-It is equivalent to -Wstrict-aliasing=3
+It is equivalent to @option{-Wstrict-aliasing=3}
@item -Wstrict-aliasing=n
@opindex Wstrict-aliasing=n
will require, in particular when determining whether a loop will be
executed at all.
-@table @option
+@table @gcctabopt
@item -Wstrict-overflow=1
Warn about cases which are both questionable and easy to avoid. For
example: @code{x + 1 > x}; with @option{-fstrict-overflow}, the
(default for -O2 and above). It warns about subscripts to arrays
that are always out of bounds. This warning is enabled by @option{-Wall}.
-@item -Wall
-@opindex Wall
-All of the above @samp{-W} options combined. This enables all the
-warnings about constructions that some users consider questionable, and
-that are easy to avoid (or modify to prevent the warning), even in
-conjunction with macros. This also enables some language-specific
-warnings described in @ref{C++ Dialect Options} and
-@ref{Objective-C and Objective-C++ Dialect Options}.
@end table
The following @option{-W@dots{}} options are not implied by @option{-Wall}.
-ftree-fre @gol
-ftree-ch @gol
-funit-at-a-time @gol
+-finline-small-functions @gol
-fmerge-constants}
@option{-O} also turns on @option{-fomit-frame-pointer} on machines
is used to keep the compiler from expanding any functions inline.
Note that if you are not optimizing, no functions can be expanded inline.
+@item -finline-small-functions
+@opindex finline-small-functions
+Integrate functions into their callers when their body is smaller than expected
+function call code (so overall size of program gets smaller). The compiler
+heuristically decides which functions are simple enough to be worth integrating
+in this way.
+
+Enabled at level @option{-O2}.
+
@item -finline-functions
@opindex finline-functions
Integrate all simple functions into their callers. The compiler
Perform more aggressive SMS based modulo scheduling with register moves
allowed. By setting this flag certain anti-dependences edges will be
deleted which will trigger the generation of reg-moves based on the
-life-range analysis.
+life-range analysis. This option is effective only with
+@option{-fmodulo-sched} enabled.
@item -fno-branch-count-reg
@opindex fno-branch-count-reg
performs jump threading (to reduce jumps to jumps). This flag is
enabled by default at @option{-O} and higher.
+@item -ftree-dse
+@opindex ftree-dse
+Perform dead store elimination (DSE) on trees. A dead store is a store into
+a memory location which will later be overwritten by another store without
+any intervening loads. In this case the earlier store can be deleted. This
+flag is enabled by default at @option{-O} and higher.
+
@item -ftree-ch
Perform loop header copying on trees. This is beneficial since it increases
effectiveness of code motion optimizations. It also saves one jump. This flag
Perform induction variable optimizations (strength reduction, induction
variable merging and induction variable elimination) on trees.
+@item -ftree-parallelize-loops=n
+@opindex ftree-parallelize-loops=n
+Parallelize loops, i.e., split their iteration space to run in n threads.
+This is only possible for loops whose iterations are independent
+and can be arbitrarily reordered. The optimization is only
+profitable on multiprocessor machines, for loops that are CPU-intensive,
+rather than constrained e.g. by memory bandwidth.
+
@item -ftree-sra
Perform scalar replacement of aggregates. This pass replaces structure
references with scalars to prevent committing structures to memory too
programs since the functions and variables become local for the whole combined
compilation unit, not for the single source file itself.
+This option is not supported for Fortran programs.
@item -fno-cprop-registers
@opindex fno-cprop-registers
@item -funsafe-math-optimizations
@opindex funsafe-math-optimizations
+
Allow optimizations for floating-point arithmetic that (a) assume
that arguments and results are valid and (b) may violate IEEE or
ANSI standards. When used at link-time, it may include libraries
an exact implementation of IEEE or ISO rules/specifications for
math functions. It may, however, yield faster code for programs
that do not require the guarantees of these specifications.
+Enables @option{-freciprocal-math} and @option{-fassociative-math}.
The default is @option{-fno-unsafe-math-optimizations}.
+@item -fassociative-math
+@opindex -fassociative-math
+
+Allow re-association of operands in series of floating-point operations.
+This violates the ISO C and C++ language standard by possibly changing
+computation result. NOTE: re-ordering may change the sign of zero as
+well as ignore NaNs and inhibit or create underflow or overflow (and
+thus cannot be used on a code which relies on rounding behavior like
+@code{(x + 2**52) - 2**52)}. May also reorder floating-point comparisons
+and thus may not be used when ordered comparisons are required.
+This flag doesn't make much sense without @option{-fno-signed-zeros}
+or @option{-fno-trapping-math} or with @option{-frounding-math}.
+
+The default is @option{-fno-associative-math}.
+
+@item -freciprocal-math
+@opindex -freciprocal-math
+
+Allow the reciprocal of a value to be used instead of dividing by
+the value if this enables optimizations. For example @code{x / y}
+can be replaced with @code{x * (1/y)} which is useful if @code{(1/y)}
+is subject to common subexpression elimination. Note that this loses
+precision and increases the number of flops operating on the value.
+
+The default is @option{-fno-reciprocal-math}.
+
@item -ffinite-math-only
@opindex ffinite-math-only
Allow optimizations for floating-point arithmetic that assume
reduce function size by being inlined. In effect it increases amount of
inlining for code having large abstraction penalty (many functions that just
pass the arguments to other functions) and decrease inlining for code with low
-abstraction penalty. The default value is 16.
+abstraction penalty. The default value is 12.
@item min-vect-loop-bound
The minimum number of iterations under which a loop will not get vectorized
@cindex Blackfin Options
@table @gcctabopt
-@item -mcpu=@var{cpu}
+@item -mcpu=@var{cpu}@r{[}-@var{sirevision}@r{]}
@opindex mcpu=
-Specifies the name of the target Blackfin processor. Currently, @var{cpu}
-can be one of @samp{bf531}, @samp{bf532}, @samp{bf533},
-@samp{bf534}, @samp{bf536}, @samp{bf537}, @samp{bf561}.
+Specifies the name of the target Blackfin processor. Currently, @var{cpu}
+can be one of @samp{bf522}, @samp{bf525}, @samp{bf527},
+@samp{bf531}, @samp{bf532}, @samp{bf533}, @samp{bf534},
+@samp{bf536}, @samp{bf537}, @samp{bf538}, @samp{bf539},
+@samp{bf542}, @samp{bf544}, @samp{bf548}, @samp{bf549},
+@samp{bf561}.
+The optional @var{sirevision} specifies the silicon revision of the target
+Blackfin processor. Any workarounds available for the targeted silicon revision
+will be enabled. If @var{sirevision} is @samp{none}, no workarounds are enabled.
+If @var{sirevision} is @samp{any}, all workarounds for the targeted processor
+will be enabled. The @code{__SILICON_REVISION__} macro is defined to two
+hexadecimal digits representing the major and minor numbers in the silicon
+revision. If @var{sirevision} is @samp{none}, the @code{__SILICON_REVISION__}
+is not defined. If @var{sirevision} is @samp{any}, the
+@code{__SILICON_REVISION__} is defined to be @code{0xffff}.
+If this optional @var{sirevision} is not used, GCC assumes the latest known
+silicon revision of the targeted Blackfin processor.
+
+Support for @samp{bf561} is incomplete. For @samp{bf561},
+Only the processor macro is defined.
Without this option, @samp{bf532} is used as the processor by default.
The corresponding predefined processor macros for @var{cpu} is to
-be defined. For the @samp{bfin-elf} toolchain, this causes the hardware
-BSP provided by libgloss to be linked in if @samp{-msim} is not given.
-Support for @samp{bf561} is incomplete; only the processor macro is defined.
+be defined. And for @samp{bfin-elf} toolchain, this causes the hardware BSP
+provided by libgloss to be linked in if @option{-msim} is not given.
@item -msim
@opindex msim
@item -mspecld-anomaly
@opindex mspecld-anomaly
When enabled, the compiler will ensure that the generated code does not
-contain speculative loads after jump instructions. This option is enabled
-by default.
+contain speculative loads after jump instructions. If this option is used,
+@code{__WORKAROUND_SPECULATIVE_LOADS} is defined.
@item -mno-specld-anomaly
@opindex mno-specld-anomaly
@opindex mcsync-anomaly
When enabled, the compiler will ensure that the generated code does not
contain CSYNC or SSYNC instructions too soon after conditional branches.
-This option is enabled by default.
+If this option is used, @code{__WORKAROUND_SPECULATIVE_SYNCS} is defined.
@item -mno-csync-anomaly
@opindex mno-csync-anomaly
@option{-mno-long-calls} will restore the default behavior. Note these
switches have no effect on how the compiler generates code to handle
function calls via function pointers.
+
+@item -mfast-fp
+@opindex mfast-fp
+Link with the fast floating-point library. This library relaxes some of
+the IEEE floating-point standard's rules for checking inputs against
+Not-a-Number (NAN), in the interest of performance.
+
+@item -minline-plt
+@opindex minline-plt
+Enable inlining of PLT entries in function calls to functions that are
+not known to bind locally. It has no effect without @option{-mfdpic}.
@end table
@node CRIS Options
@itemx -mno-sse4
@item -msse4a
@item -mno-sse4a
+@item -msse5
+@itemx -mno-sse5
@item -m3dnow
@itemx -mno-3dnow
@item -mpopcnt
@opindex m3dnow
@opindex mno-3dnow
These switches enable or disable the use of instructions in the MMX,
-SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4A, ABM or 3DNow! extended
+SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4A, SSE5, ABM or 3DNow! extended
instruction sets.
These extensions are also available as built-in functions: see
@ref{X86 Built-in Functions}, for details of the functions enabled and
vectorized variants). These instructions will be generated only when
@option{-funsafe-math-optimizations} is enabled.
+@item -mveclibabi=@var{type}
+@opindex mveclibabi
+Specifies the ABI type to use for vectorizing intrinsics using an
+external library. Supported types are @code{acml} for the AMD
+math core library style of interfacing. GCC will currently emit
+calls to @code{__vrd2_sin}, @code{__vrd2_cos}, @code{__vrd2_exp},
+@code{__vrd2_log}, @code{__vrd2_log2}, @code{__vrd2_log10},
+@code{__vrs4_sinf}, @code{__vrs4_cosf}, @code{__vrs4_expf},
+@code{__vrs4_logf}, @code{__vrs4_log2f}, @code{__vrs4_log10f}
+and @code{__vrs4_powf} when using this type and @option{-ftree-vectorize}
+is enabled. A ACML ABI compatible library will have to be specified
+at link time.
+
@item -mpush-args
@itemx -mno-push-args
@opindex mpush-args
segment to cover the entire TLS area.
For systems that use GNU libc, the default is on.
+
+@item -mfused-madd
+@itemx -mno-fused-madd
+@opindex mfused-madd
+Enable automatic generation of fused floating point multiply-add instructions
+if the ISA supports such instructions. The -mfused-madd option is on by
+default. The fused multiply-add instructions have a different
+rounding behavior compared to executing a multiply followed by an add.
@end table
These @samp{-m} switches are supported in addition to the above
@multitable @columnfractions 0.20 0.80
@item @strong{Family} @tab @strong{@samp{-mcpu} arguments}
+@item @samp{51qe} @tab @samp{51qe}
@item @samp{5206} @tab @samp{5202} @samp{5204} @samp{5206}
@item @samp{5206e} @tab @samp{5206e}
@item @samp{5208} @tab @samp{5207} @samp{5208}
The M680x0 microarchitectures are: @samp{68000}, @samp{68010},
@samp{68020}, @samp{68030}, @samp{68040}, @samp{68060}
and @samp{cpu32}. The ColdFire microarchitectures
-are: @samp{cfv2}, @samp{cfv3}, @samp{cfv4} and @samp{cfv4e}.
+are: @samp{cfv1}, @samp{cfv2}, @samp{cfv3}, @samp{cfv4} and @samp{cfv4e}.
You can also use @option{-mtune=68020-40} for code that needs
to run relatively well on 68020, 68030 and 68040 targets.
Generate (do not generate) MIPS16 code. If GCC is targetting a
MIPS32 or MIPS64 architecture, it will make use of the MIPS16e ASE@.
+MIPS16 code generation can also be controlled on a per-function basis
+by means of @code{mips16} and @code{nomips16} attributes.
+@xref{Function Attributes}, for more information.
+
+@item -mflip-mips16
+@opindex mflip-mips16
+Generate MIPS16 code on alternating functions. This option is provided
+for regression testing of mixed MIPS16/non-MIPS16 code generation, and is
+not intended for ordinary use in compiling user code.
+
+@item -minterlink-mips16
+@itemx -mno-interlink-mips16
+@opindex minterlink-mips16
+@opindex mno-interlink-mips16
+Require (do not require) that non-MIPS16 code be link-compatible with
+MIPS16 code.
+
+For example, non-MIPS16 code cannot jump directly to MIPS16 code;
+it must either use a call or an indirect jump. @option{-minterlink-mips16}
+therefore disables direct jumps unless GCC knows that the target of the
+jump is not MIPS16.
+
@item -mabi=32
@itemx -mabi=o64
@itemx -mabi=n32
Assume that the floating-point coprocessor supports double-precision
operations. This is the default.
+@item -mllsc
+@itemx -mno-llsc
+@opindex mllsc
+@opindex mno-llsc
+Use (do not use) @samp{ll}, @samp{sc}, and @samp{sync} instructions to
+implement atomic memory built-in functions. When neither option is
+specified, GCC will use the instructions if the target architecture
+supports them.
+
+@option{-mllsc} is useful if the runtime environment can emulate the
+instructions and @option{-mno-llsc} can be useful when compiling for
+nonstandard ISAs. You can make either option the default by
+configuring GCC with @option{--with-llsc} and @option{--without-llsc}
+respectively. @option{--with-llsc} is the default for some
+configurations; see the installation documentation for details.
+
@item -mdsp
@itemx -mno-dsp
@opindex mdsp
@item -G @var{num}
@opindex G
-@cindex smaller data references (MIPS)
-@cindex gp-relative references (MIPS)
-Put global and static items less than or equal to @var{num} bytes into
-the small data or bss section instead of the normal data or bss section.
-This allows the data to be accessed using a single instruction.
+Put definitions of externally-visible data in a small data section
+if that data is no bigger than @var{num} bytes. GCC can then access
+the data more efficiently; see @option{-mgpopt} for details.
+
+The default @option{-G} option depends on the configuration.
+
+@item -mlocal-sdata
+@itemx -mno-local-sdata
+@opindex mlocal-sdata
+@opindex mno-local-sdata
+Extend (do not extend) the @option{-G} behavior to local data too,
+such as to static variables in C. @option{-mlocal-sdata} is the
+default for all configurations.
+
+If the linker complains that an application is using too much small data,
+you might want to try rebuilding the less performance-critical parts with
+@option{-mno-local-sdata}. You might also want to build large
+libraries with @option{-mno-local-sdata}, so that the libraries leave
+more room for the main program.
+
+@item -mextern-sdata
+@itemx -mno-extern-sdata
+@opindex mextern-sdata
+@opindex mno-extern-sdata
+Assume (do not assume) that externally-defined data will be in
+a small data section if that data is within the @option{-G} limit.
+@option{-mextern-sdata} is the default for all configurations.
+
+If you compile a module @var{Mod} with @option{-mextern-sdata} @option{-G
+@var{num}} @option{-mgpopt}, and @var{Mod} references a variable @var{Var}
+that is no bigger than @var{num} bytes, you must make sure that @var{Var}
+is placed in a small data section. If @var{Var} is defined by another
+module, you must either compile that module with a high-enough
+@option{-G} setting or attach a @code{section} attribute to @var{Var}'s
+definition. If @var{Var} is common, you must link the application
+with a high-enough @option{-G} setting.
+
+The easiest way of satisfying these restrictions is to compile
+and link every module with the same @option{-G} option. However,
+you may wish to build a library that supports several different
+small data limits. You can do this by compiling the library with
+the highest supported @option{-G} setting and additionally using
+@option{-mno-extern-sdata} to stop the library from making assumptions
+about externally-defined data.
+
+@item -mgpopt
+@itemx -mno-gpopt
+@opindex mgpopt
+@opindex mno-gpopt
+Use (do not use) GP-relative accesses for symbols that are known to be
+in a small data section; see @option{-G}, @option{-mlocal-sdata} and
+@option{-mextern-sdata}. @option{-mgpopt} is the default for all
+configurations.
+
+@option{-mno-gpopt} is useful for cases where the @code{$gp} register
+might not hold the value of @code{_gp}. For example, if the code is
+part of a library that might be used in a boot monitor, programs that
+call boot monitor routines will pass an unknown value in @code{$gp}.
+(In such situations, the boot monitor itself would usually be compiled
+with @option{-G0}.)
-All modules should be compiled with the same @option{-G @var{num}}
-value.
+@option{-mno-gpopt} implies @option{-mno-local-sdata} and
+@option{-mno-extern-sdata}.
@item -membedded-data
@itemx -mno-embedded-data
This switch enables or disables the generation of SPE simd
instructions.
+@item -mpaired
+@itemx -mno-paired
+@opindex mpaired
+@opindex mno-paired
+This switch enables or disables the generation of PAIRED simd
+instructions.
+
@item -mspe=@var{yes/no}
This option has been deprecated. Use @option{-mspe} and
@option{-mno-spe} instead.
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