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NAME

       AS - the portable GNU assembler.

SYNOPSIS

       as [-a[cdghlns][=file]] [--alternate] [-D]
        [--compress-debug-sections]  [--nocompress-debug-sections]
        [--debug-prefix-map old=new]
        [--defsym sym=val] [-f] [-g] [--gstabs]
        [--gstabs+] [--gdwarf-2] [--help] [-I dir] [-J]
        [-K] [-L] [--listing-lhs-width=NUM]
        [--listing-lhs-width2=NUM] [--listing-rhs-width=NUM]
        [--listing-cont-lines=NUM] [--keep-locals] [-o
        objfile] [-R] [--reduce-memory-overheads] [--statistics]
        [-v] [-version] [--version] [-W] [--warn]
        [--fatal-warnings] [-w] [-x] [-Z] [@FILE]
        [--target-help] [target-options]
        [--|files ...]

       Target Alpha options:
          [-mcpu]
          [-mdebug | -no-mdebug]
          [-replace | -noreplace]
          [-relax] [-g] [-Gsize]
          [-F] [-32addr]

       Target ARC options:
          [-marc[5|6|7|8]]
          [-EB|-EL]

       Target ARM options:
          [-mcpu=processor[+extension...]]
          [-march=architecture[+extension...]]
          [-mfpu=floating-point-format]
          [-mfloat-abi=abi]
          [-meabi=ver]
          [-mthumb]
          [-EB|-EL]
          [-mapcs-32|-mapcs-26|-mapcs-float|
           -mapcs-reentrant]
          [-mthumb-interwork] [-k]

       Target Blackfin options:
          [-mcpu=processor[-sirevision]]
          [-mfdpic]
          [-mno-fdpic]
          [-mnopic]

       Target CRIS options:
          [--underscore | --no-underscore]
          [--pic] [-N]
          [--emulation=criself | --emulation=crisaout]
          [--march=v0_v10 | --march=v10 | --march=v32 |
       --march=common_v10_v32]

       Target D10V options:
          [-O]

       Target D30V options:
          [-O|-n|-N]

       Target H8/300 options:
          [-h-tick-hex]

       Target i386 options:
          [--32|--64] [-n]
          [-march=CPU[+EXTENSION...]] [-mtune=CPU]

       Target i960 options:
          [-ACA|-ACA_A|-ACB|-ACC|-AKA|-AKB|
           -AKC|-AMC]
          [-b] [-no-relax]

       Target IA-64 options:
          [-mconstant-gp|-mauto-pic]
          [-milp32|-milp64|-mlp64|-mp64]
          [-mle|mbe]
          [-mtune=itanium1|-mtune=itanium2]
          [-munwind-check=warning|-munwind-check=error]
          [-mhint.b=ok|-mhint.b=warning|-mhint.b=error]
          [-x|-xexplicit] [-xauto] [-xdebug]

       Target IP2K options:
          [-mip2022|-mip2022ext]

       Target M32C options:
          [-m32c|-m16c] [-relax] [-h-tick-hex]

       Target M32R options:
          [--m32rx|--[no-]warn-explicit-parallel-conflicts|
          --W[n]p]

       Target M680X0 options:
          [-l] [-m68000|-m68010|-m68020|...]

       Target M68HC11 options:
          [-m68hc11|-m68hc12|-m68hcs12]
          [-mshort|-mlong]
          [-mshort-double|-mlong-double]
          [--force-long-branches] [--short-branches]
          [--strict-direct-mode] [--print-insn-syntax]
          [--print-opcodes] [--generate-example]

       Target MCORE options:
          [-jsri2bsr] [-sifilter] [-relax]
          [-mcpu=[210|340]] Target MICROBLAZE options:

       Target MIPS options:
          [-nocpp] [-EL] [-EB] [-O[optimization level]]
          [-g[debug level]] [-G num] [-KPIC] [-call_shared]
          [-non_shared] [-xgot [-mvxworks-pic]
          [-mabi=ABI] [-32] [-n32] [-64] [-mfp32] [-mgp32]
          [-march=CPU] [-mtune=CPU] [-mips1] [-mips2]
          [-mips3] [-mips4] [-mips5] [-mips32] [-mips32r2]
          [-mips64] [-mips64r2]
          [-construct-floats] [-no-construct-floats]
          [-trap] [-no-break] [-break] [-no-trap]
          [-mips16] [-no-mips16]
          [-msmartmips] [-mno-smartmips]
          [-mips3d] [-no-mips3d]
          [-mdmx] [-no-mdmx]
          [-mdsp] [-mno-dsp]
          [-mdspr2] [-mno-dspr2]
          [-mmt] [-mno-mt]
          [-mfix7000] [-mno-fix7000]
          [-mfix-vr4120] [-mno-fix-vr4120]
          [-mfix-vr4130] [-mno-fix-vr4130]
          [-mdebug] [-no-mdebug]
          [-mpdr] [-mno-pdr]

       Target MMIX options:
          [--fixed-special-register-names] [--globalize-symbols]
          [--gnu-syntax] [--relax] [--no-predefined-symbols]
          [--no-expand] [--no-merge-gregs] [-x]
          [--linker-allocated-gregs]

       Target PDP11 options:
          [-mpic|-mno-pic] [-mall] [-mno-extensions]
          [-mextension|-mno-extension]
          [-mcpu] [-mmachine]

       Target picoJava options:
          [-mb|-me]

       Target PowerPC options:
          [-mpwrx|-mpwr2|-mpwr|-m601|-mppc|-mppc32|-m603|-m604|
           -m403|-m405|-mppc64|-m620|-mppc64bridge|-mbooke]
          [-mcom|-many|-maltivec|-mvsx] [-memb]
          [-mregnames|-mno-regnames]
          [-mrelocatable|-mrelocatable-lib]
          [-mlittle|-mlittle-endian|-mbig|-mbig-endian]
          [-msolaris|-mno-solaris]

       Target RX options:
          [-mlittle-endian|-mbig-endian]
          [-m32bit-ints|-m16bit-ints]
          [-m32bit-doubles|-m64bit-doubles]

       Target s390 options:
          [-m31|-m64] [-mesa|-mzarch] [-march=CPU]
          [-mregnames|-mno-regnames]
          [-mwarn-areg-zero]

       Target SCORE options:
          [-EB][-EL][-FIXDD][-NWARN]
          [-SCORE5][-SCORE5U][-SCORE7][-SCORE3]
          [-march=score7][-march=score3]
          [-USE_R1][-KPIC][-O0][-G num][-V]

       Target SPARC options:
          [-Av6|-Av7|-Av8|-Asparclet|-Asparclite
           -Av8plus|-Av8plusa|-Av9|-Av9a]
          [-xarch=v8plus|-xarch=v8plusa] [-bump]
          [-32|-64]

       Target TIC54X options:
        [-mcpu=54[123589]|-mcpu=54[56]lp] [-mfar-mode|-mf]
        [-merrors-to-file <filename>|-me <filename>]

       Target TIC6X options:
          [-march=arch] [-matomic|-mno-atomic]
          [-mbig-endian|-mlittle-endian]

       Target Z80 options:
         [-z80] [-r800]
         [ -ignore-undocumented-instructions] [-Wnud]
         [ -ignore-unportable-instructions] [-Wnup]
         [ -warn-undocumented-instructions] [-Wud]
         [ -warn-unportable-instructions] [-Wup]
         [ -forbid-undocumented-instructions] [-Fud]
         [ -forbid-unportable-instructions] [-Fup]

       Target Xtensa options:
        [--[no-]text-section-literals] [--[no-]absolute-literals]
        [--[no-]target-align] [--[no-]longcalls]
        [--[no-]transform]
        [--rename-section oldname=newname]

DESCRIPTION

       GNU as is really a family of assemblers.  If you use (or have used) the
       GNU assembler on one architecture, you should find a fairly similar
       environment when you use it on another architecture.  Each version has
       much in common with the others, including object file formats, most
       assembler directives (often called pseudo-ops) and assembler syntax.

       as is primarily intended to assemble the output of the GNU C compiler
       "gcc" for use by the linker "ld".  Nevertheless, we've tried to make as
       assemble correctly everything that other assemblers for the same
       machine would assemble.  Any exceptions are documented explicitly.
       This doesn't mean as always uses the same syntax as another assembler
       for the same architecture; for example, we know of several incompatible
       versions of 680x0 assembly language syntax.

       Each time you run as it assembles exactly one source program.  The
       source program is made up of one or more files.  (The standard input is
       also a file.)

       You give as a command line that has zero or more input file names.  The
       input files are read (from left file name to right).  A command line
       argument (in any position) that has no special meaning is taken to be
       an input file name.

       If you give as no file names it attempts to read one input file from
       the as standard input, which is normally your terminal.  You may have
       to type ctl-D to tell as there is no more program to assemble.

       Use -- if you need to explicitly name the standard input file in your
       command line.

       If the source is empty, as produces a small, empty object file.

       as may write warnings and error messages to the standard error file
       (usually your terminal).  This should not happen when  a compiler runs
       as automatically.  Warnings report an assumption made so that as could
       keep assembling a flawed program; errors report a grave problem that
       stops the assembly.

       If you are invoking as via the GNU C compiler, you can use the -Wa
       option to pass arguments through to the assembler.  The assembler
       arguments must be separated from each other (and the -Wa) by commas.
       For example:

               gcc -c -g -O -Wa,-alh,-L file.c

       This passes two options to the assembler: -alh (emit a listing to
       standard output with high-level and assembly source) and -L (retain
       local symbols in the symbol table).

       Usually you do not need to use this -Wa mechanism, since many compiler
       command-line options are automatically passed to the assembler by the
       compiler.  (You can call the GNU compiler driver with the -v option to
       see precisely what options it passes to each compilation pass,
       including the assembler.)

OPTIONS

       @file
           Read command-line options from file.  The options read are inserted
           in place of the original @file option.  If file does not exist, or
           cannot be read, then the option will be treated literally, and not
           removed.

           Options in file are separated by whitespace.  A whitespace
           character may be included in an option by surrounding the entire
           option in either single or double quotes.  Any character (including
           a backslash) may be included by prefixing the character to be
           included with a backslash.  The file may itself contain additional
           @file options; any such options will be processed recursively.

       -a[cdghlmns]
           Turn on listings, in any of a variety of ways:

           -ac omit false conditionals

           -ad omit debugging directives

           -ag include general information, like as version and options passed

           -ah include high-level source

           -al include assembly

           -am include macro expansions

           -an omit forms processing

           -as include symbols

           =file
               set the name of the listing file

           You may combine these options; for example, use -aln for assembly
           listing without forms processing.  The =file option, if used, must
           be the last one.  By itself, -a defaults to -ahls.

       --alternate
           Begin in alternate macro mode.

       --compress-debug-sections
           Compress DWARF debug sections using zlib.  The debug sections are
           renamed to begin with .zdebug, and the resulting object file may
           not be compatible with older linkers and object file utilities.

       --nocompress-debug-sections
           Do not compress DWARF debug sections.  This is the default.

       -D  Ignored.  This option is accepted for script compatibility with
           calls to other assemblers.

       --debug-prefix-map old=new
           When assembling files in directory old, record debugging
           information describing them as in new instead.

       --defsym sym=value
           Define the symbol sym to be value before assembling the input file.
           value must be an integer constant.  As in C, a leading 0x indicates
           a hexadecimal value, and a leading 0 indicates an octal value.  The
           value of the symbol can be overridden inside a source file via the
           use of a ".set" pseudo-op.

       -f  "fast"---skip whitespace and comment preprocessing (assume source
           is compiler output).

       -g
       --gen-debug
           Generate debugging information for each assembler source line using
           whichever debug format is preferred by the target.  This currently
           means either STABS, ECOFF or DWARF2.

       --gstabs
           Generate stabs debugging information for each assembler line.  This
           may help debugging assembler code, if the debugger can handle it.

       --gstabs+
           Generate stabs debugging information for each assembler line, with
           GNU extensions that probably only gdb can handle, and that could
           make other debuggers crash or refuse to read your program.  This
           may help debugging assembler code.  Currently the only GNU
           extension is the location of the current working directory at
           assembling time.

       --gdwarf-2
           Generate DWARF2 debugging information for each assembler line.
           This may help debugging assembler code, if the debugger can handle
           it.  Note---this option is only supported by some targets, not all
           of them.

       --help
           Print a summary of the command line options and exit.

       --target-help
           Print a summary of all target specific options and exit.

       -I dir
           Add directory dir to the search list for ".include" directives.

       -J  Don't warn about signed overflow.

       -K  Issue warnings when difference tables altered for long
           displacements.

       -L
       --keep-locals
           Keep (in the symbol table) local symbols.  These symbols start with
           system-specific local label prefixes, typically .L for ELF systems
           or L for traditional a.out systems.

       --listing-lhs-width=number
           Set the maximum width, in words, of the output data column for an
           assembler listing to number.

       --listing-lhs-width2=number
           Set the maximum width, in words, of the output data column for
           continuation lines in an assembler listing to number.

       --listing-rhs-width=number
           Set the maximum width of an input source line, as displayed in a
           listing, to number bytes.

       --listing-cont-lines=number
           Set the maximum number of lines printed in a listing for a single
           line of input to number + 1.

       -o objfile
           Name the object-file output from as objfile.

       -R  Fold the data section into the text section.

           Set the default size of GAS's hash tables to a prime number close
           to number.  Increasing this value can reduce the length of time it
           takes the assembler to perform its tasks, at the expense of
           increasing the assembler's memory requirements.  Similarly reducing
           this value can reduce the memory requirements at the expense of
           speed.

       --reduce-memory-overheads
           This option reduces GAS's memory requirements, at the expense of
           making the assembly processes slower.  Currently this switch is a
           synonym for --hash-size=4051, but in the future it may have other
           effects as well.

       --statistics
           Print the maximum space (in bytes) and total time (in seconds) used
           by assembly.

       --strip-local-absolute
           Remove local absolute symbols from the outgoing symbol table.

       -v
       -version
           Print the as version.

       --version
           Print the as version and exit.

       -W
       --no-warn
           Suppress warning messages.

       --fatal-warnings
           Treat warnings as errors.

       --warn
           Don't suppress warning messages or treat them as errors.

       -w  Ignored.

       -x  Ignored.

       -Z  Generate an object file even after errors.

       -- | files ...
           Standard input, or source files to assemble.

       The following options are available when as is configured for an ARC
       processor.

       -marc[5|6|7|8]
           This option selects the core processor variant.

       -EB | -EL
           Select either big-endian (-EB) or little-endian (-EL) output.

       The following options are available when as is configured for the ARM
       processor family.

       -mcpu=processor[+extension...]
           Specify which ARM processor variant is the target.

       -march=architecture[+extension...]
           Specify which ARM architecture variant is used by the target.

       -mfpu=floating-point-format
           Select which Floating Point architecture is the target.

       -mfloat-abi=abi
           Select which floating point ABI is in use.

       -mthumb
           Enable Thumb only instruction decoding.

       -mapcs-32 | -mapcs-26 | -mapcs-float | -mapcs-reentrant
           Select which procedure calling convention is in use.

       -EB | -EL
           Select either big-endian (-EB) or little-endian (-EL) output.

       -mthumb-interwork
           Specify that the code has been generated with interworking between
           Thumb and ARM code in mind.

       -k  Specify that PIC code has been generated.

       The following options are available when as is configured for the
       Blackfin processor family.

       -mcpu=processor[-sirevision]
           This option specifies the target processor.  The optional
           sirevision is not used in assembler.

       -mfdpic
           Assemble for the FDPIC ABI.

       -mno-fdpic
       -mnopic
           Disable -mfdpic.

       See the info pages for documentation of the CRIS-specific options.

       The following options are available when as is configured for a D10V
       processor.

       -O  Optimize output by parallelizing instructions.

       The following options are available when as is configured for a D30V
       processor.

       -O  Optimize output by parallelizing instructions.

       -n  Warn when nops are generated.

       -N  Warn when a nop after a 32-bit multiply instruction is generated.

       The following options are available when as is configured for the Intel
       80960 processor.

       -ACA | -ACA_A | -ACB | -ACC | -AKA | -AKB | -AKC | -AMC
           Specify which variant of the 960 architecture is the target.

       -b  Add code to collect statistics about branches taken.

       -no-relax
           Do not alter compare-and-branch instructions for long
           displacements; error if necessary.

       The following options are available when as is configured for the
       Ubicom IP2K series.

       -mip2022ext
           Specifies that the extended IP2022 instructions are allowed.

       -mip2022
           Restores the default behaviour, which restricts the permitted
           instructions to just the basic IP2022 ones.

       The following options are available when as is configured for the
       Renesas M32C and M16C processors.

       -m32c
           Assemble M32C instructions.

       -m16c
           Assemble M16C instructions (the default).

       -relax
           Enable support for link-time relaxations.

       -h-tick-hex
           Support H'00 style hex constants in addition to 0x00 style.

       The following options are available when as is configured for the
       Renesas M32R (formerly Mitsubishi M32R) series.

       --m32rx
           Specify which processor in the M32R family is the target.  The
           default is normally the M32R, but this option changes it to the
           M32RX.

       --warn-explicit-parallel-conflicts or --Wp
           Produce warning messages when questionable parallel constructs are
           encountered.

       --no-warn-explicit-parallel-conflicts or --Wnp
           Do not produce warning messages when questionable parallel
           constructs are encountered.

       The following options are available when as is configured for the
       Motorola 68000 series.

       -l  Shorten references to undefined symbols, to one word instead of
           two.

       -m68000 | -m68008 | -m68010 | -m68020 | -m68030
       | -m68040 | -m68060 | -m68302 | -m68331 | -m68332
       | -m68333 | -m68340 | -mcpu32 | -m5200
           Specify what processor in the 68000 family is the target.  The
           default is normally the 68020, but this can be changed at
           configuration time.

       -m68881 | -m68882 | -mno-68881 | -mno-68882
           The target machine does (or does not) have a floating-point
           coprocessor.  The default is to assume a coprocessor for 68020,
           68030, and cpu32.  Although the basic 68000 is not compatible with
           the 68881, a combination of the two can be specified, since it's
           possible to do emulation of the coprocessor instructions with the
           main processor.

       -m68851 | -mno-68851
           The target machine does (or does not) have a memory-management unit
           coprocessor.  The default is to assume an MMU for 68020 and up.

       For details about the PDP-11 machine dependent features options, see
       PDP-11-Options.

       -mpic | -mno-pic
           Generate position-independent (or position-dependent) code.  The
           default is -mpic.

       -mall
       -mall-extensions
           Enable all instruction set extensions.  This is the default.

       -mno-extensions
           Disable all instruction set extensions.

       -mextension | -mno-extension
           Enable (or disable) a particular instruction set extension.

       -mcpu
           Enable the instruction set extensions supported by a particular
           CPU, and disable all other extensions.

       -mmachine
           Enable the instruction set extensions supported by a particular
           machine model, and disable all other extensions.

       The following options are available when as is configured for a
       picoJava processor.

       -mb Generate "big endian" format output.

       -ml Generate "little endian" format output.

       The following options are available when as is configured for the
       Motorola 68HC11 or 68HC12 series.

       -m68hc11 | -m68hc12 | -m68hcs12
           Specify what processor is the target.  The default is defined by
           the configuration option when building the assembler.

       -mshort
           Specify to use the 16-bit integer ABI.

       -mlong
           Specify to use the 32-bit integer ABI.

       -mshort-double
           Specify to use the 32-bit double ABI.

       -mlong-double
           Specify to use the 64-bit double ABI.

       --force-long-branches
           Relative branches are turned into absolute ones. This concerns
           conditional branches, unconditional branches and branches to a sub
           routine.

       -S | --short-branches
           Do not turn relative branches into absolute ones when the offset is
           out of range.

       --strict-direct-mode
           Do not turn the direct addressing mode into extended addressing
           mode when the instruction does not support direct addressing mode.

       --print-insn-syntax
           Print the syntax of instruction in case of error.

       --print-opcodes
           print the list of instructions with syntax and then exit.

       --generate-example
           print an example of instruction for each possible instruction and
           then exit.  This option is only useful for testing as.

       The following options are available when as is configured for the SPARC
       architecture:

       -Av6 | -Av7 | -Av8 | -Asparclet | -Asparclite
       -Av8plus | -Av8plusa | -Av9 | -Av9a
           Explicitly select a variant of the SPARC architecture.

           -Av8plus and -Av8plusa select a 32 bit environment.  -Av9 and -Av9a
           select a 64 bit environment.

           -Av8plusa and -Av9a enable the SPARC V9 instruction set with
           UltraSPARC extensions.

       -xarch=v8plus | -xarch=v8plusa
           For compatibility with the Solaris v9 assembler.  These options are
           equivalent to -Av8plus and -Av8plusa, respectively.

       -bump
           Warn when the assembler switches to another architecture.

       The following options are available when as is configured for the 'c54x
       architecture.

       -mfar-mode
           Enable extended addressing mode.  All addresses and relocations
           will assume extended addressing (usually 23 bits).

       -mcpu=CPU_VERSION
           Sets the CPU version being compiled for.

       -merrors-to-file FILENAME
           Redirect error output to a file, for broken systems which don't
           support such behaviour in the shell.

       The following options are available when as is configured for a MIPS
       processor.

       -G num
           This option sets the largest size of an object that can be
           referenced implicitly with the "gp" register.  It is only accepted
           for targets that use ECOFF format, such as a DECstation running
           Ultrix.  The default value is 8.

       -EB Generate "big endian" format output.

       -EL Generate "little endian" format output.

       -mips1
       -mips2
       -mips3
       -mips4
       -mips5
       -mips32
       -mips32r2
       -mips64
       -mips64r2
           Generate code for a particular MIPS Instruction Set Architecture
           level.  -mips1 is an alias for -march=r3000, -mips2 is an alias for
           -march=r6000, -mips3 is an alias for -march=r4000 and -mips4 is an
           alias for -march=r8000.  -mips5, -mips32, -mips32r2, -mips64, and
           -mips64r2 correspond to generic MIPS V, MIPS32, MIPS32 Release 2,
           MIPS64, and MIPS64 Release 2 ISA processors, respectively.

       -march=CPU
           Generate code for a particular MIPS cpu.

       -mtune=cpu
           Schedule and tune for a particular MIPS cpu.

       -mfix7000
       -mno-fix7000
           Cause nops to be inserted if the read of the destination register
           of an mfhi or mflo instruction occurs in the following two
           instructions.

       -mdebug
       -no-mdebug
           Cause stabs-style debugging output to go into an ECOFF-style
           .mdebug section instead of the standard ELF .stabs sections.

       -mpdr
       -mno-pdr
           Control generation of ".pdr" sections.

       -mgp32
       -mfp32
           The register sizes are normally inferred from the ISA and ABI, but
           these flags force a certain group of registers to be treated as 32
           bits wide at all times.  -mgp32 controls the size of general-
           purpose registers and -mfp32 controls the size of floating-point
           registers.

       -mips16
       -no-mips16
           Generate code for the MIPS 16 processor.  This is equivalent to
           putting ".set mips16" at the start of the assembly file.
           -no-mips16 turns off this option.

       -msmartmips
       -mno-smartmips
           Enables the SmartMIPS extension to the MIPS32 instruction set. This
           is equivalent to putting ".set smartmips" at the start of the
           assembly file.  -mno-smartmips turns off this option.

       -mips3d
       -no-mips3d
           Generate code for the MIPS-3D Application Specific Extension.  This
           tells the assembler to accept MIPS-3D instructions.  -no-mips3d
           turns off this option.

       -mdmx
       -no-mdmx
           Generate code for the MDMX Application Specific Extension.  This
           tells the assembler to accept MDMX instructions.  -no-mdmx turns
           off this option.

       -mdsp
       -mno-dsp
           Generate code for the DSP Release 1 Application Specific Extension.
           This tells the assembler to accept DSP Release 1 instructions.
           -mno-dsp turns off this option.

       -mdspr2
       -mno-dspr2
           Generate code for the DSP Release 2 Application Specific Extension.
           This option implies -mdsp.  This tells the assembler to accept DSP
           Release 2 instructions.  -mno-dspr2 turns off this option.

       -mmt
       -mno-mt
           Generate code for the MT Application Specific Extension.  This
           tells the assembler to accept MT instructions.  -mno-mt turns off
           this option.

       --construct-floats
       --no-construct-floats
           The --no-construct-floats option disables the construction of
           double width floating point constants by loading the two halves of
           the value into the two single width floating point registers that
           make up the double width register.  By default --construct-floats
           is selected, allowing construction of these floating point
           constants.

       --emulation=name
           This option causes as to emulate as configured for some other
           target, in all respects, including output format (choosing between
           ELF and ECOFF only), handling of pseudo-opcodes which may generate
           debugging information or store symbol table information, and
           default endianness.  The available configuration names are:
           mipsecoff, mipself, mipslecoff, mipsbecoff, mipslelf, mipsbelf.
           The first two do not alter the default endianness from that of the
           primary target for which the assembler was configured; the others
           change the default to little- or big-endian as indicated by the b
           or l in the name.  Using -EB or -EL will override the endianness
           selection in any case.

           This option is currently supported only when the primary target as
           is configured for is a MIPS ELF or ECOFF target.  Furthermore, the
           primary target or others specified with --enable-targets=... at
           configuration time must include support for the other format, if
           both are to be available.  For example, the Irix 5 configuration
           includes support for both.

           Eventually, this option will support more configurations, with more
           fine-grained control over the assembler's behavior, and will be
           supported for more processors.

       -nocpp
           as ignores this option.  It is accepted for compatibility with the
           native tools.

       --trap
       --no-trap
       --break
       --no-break
           Control how to deal with multiplication overflow and division by
           zero.  --trap or --no-break (which are synonyms) take a trap
           exception (and only work for Instruction Set Architecture level 2
           and higher); --break or --no-trap (also synonyms, and the default)
           take a break exception.

       -n  When this option is used, as will issue a warning every time it
           generates a nop instruction from a macro.

       The following options are available when as is configured for an MCore
       processor.

       -jsri2bsr
       -nojsri2bsr
           Enable or disable the JSRI to BSR transformation.  By default this
           is enabled.  The command line option -nojsri2bsr can be used to
           disable it.

       -sifilter
       -nosifilter
           Enable or disable the silicon filter behaviour.  By default this is
           disabled.  The default can be overridden by the -sifilter command
           line option.

       -relax
           Alter jump instructions for long displacements.

       -mcpu=[210|340]
           Select the cpu type on the target hardware.  This controls which
           instructions can be assembled.

       -EB Assemble for a big endian target.

       -EL Assemble for a little endian target.

       See the info pages for documentation of the MMIX-specific options.

       See the info pages for documentation of the RX-specific options.

       The following options are available when as is configured for the s390
       processor family.

       -m31
       -m64
           Select the word size, either 31/32 bits or 64 bits.

       -mesa
       -mzarch
           Select the architecture mode, either the Enterprise System
           Architecture (esa) or the z/Architecture mode (zarch).

       -march=processor
           Specify which s390 processor variant is the target, g6, g6, z900,
           z990, z9-109, z9-ec, or z10.

       -mregnames
       -mno-regnames
           Allow or disallow symbolic names for registers.

       -mwarn-areg-zero
           Warn whenever the operand for a base or index register has been
           specified but evaluates to zero.

       The following options are available when as is configured for a
       TMS320C6000 processor.

       -march=arch
           Enable (only) instructions from architecture arch.  By default, all
           instructions are permitted.

           The following values of arch are accepted: "c62x", "c64x", "c64x+",
           "c67x", "c67x+", "c674x".

       -matomic
       -mno-atomic
           Enable or disable the optional C64x+ atomic operation instructions.
           By default, they are enabled if no -march option is given, or if an
           architecture is specified with -march that implies these
           instructions are present (currently, there are no such
           architectures); they are disabled if an architecture is specified
           with -march on which the instructions are optional or not present.
           This option overrides such a default from the architecture,
           independent of the order in which the -march or -matomic or
           -mno-atomic options are passed.

       -mbig-endian
       -mlittle-endian
           Generate code for the specified endianness.  The default is little-
           endian.

       The following options are available when as is configured for an Xtensa
       processor.

       --text-section-literals | --no-text-section-literals
           With --text-section-literals, literal pools are interspersed in the
           text section.  The default is --no-text-section-literals, which
           places literals in a separate section in the output file.  These
           options only affect literals referenced via PC-relative "L32R"
           instructions; literals for absolute mode "L32R" instructions are
           handled separately.

       --absolute-literals | --no-absolute-literals
           Indicate to the assembler whether "L32R" instructions use absolute
           or PC-relative addressing.  The default is to assume absolute
           addressing if the Xtensa processor includes the absolute "L32R"
           addressing option.  Otherwise, only the PC-relative "L32R" mode can
           be used.

       --target-align | --no-target-align
           Enable or disable automatic alignment to reduce branch penalties at
           the expense of some code density.  The default is --target-align.

       --longcalls | --no-longcalls
           Enable or disable transformation of call instructions to allow
           calls across a greater range of addresses.  The default is
           --no-longcalls.

       --transform | --no-transform
           Enable or disable all assembler transformations of Xtensa
           instructions.  The default is --transform; --no-transform should be
           used only in the rare cases when the instructions must be exactly
           as specified in the assembly source.

       --rename-section oldname=newname
           When generating output sections, rename the oldname section to
           newname.

       The following options are available when as is configured for a Z80
       family processor.

       -z80
           Assemble for Z80 processor.

       -r800
           Assemble for R800 processor.

       -ignore-undocumented-instructions
       -Wnud
           Assemble undocumented Z80 instructions that also work on R800
           without warning.

       -ignore-unportable-instructions
       -Wnup
           Assemble all undocumented Z80 instructions without warning.

       -warn-undocumented-instructions
       -Wud
           Issue a warning for undocumented Z80 instructions that also work on
           R800.

       -warn-unportable-instructions
       -Wup
           Issue a warning for undocumented Z80 instructions that do not work
           on R800.

       -forbid-undocumented-instructions
       -Fud
           Treat all undocumented instructions as errors.

       -forbid-unportable-instructions
       -Fup
           Treat undocumented Z80 instructions that do not work on R800 as
           errors.

SEE ALSO

       gcc(1), ld(1), and the Info entries for binutils and ld.

COPYRIGHT

       Copyright (c) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
       2000, 2001, 2002, 2006, 2007, 2008, 2009, 2010 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 1.3 or
       any later version published by the Free Software Foundation; with no
       Invariant Sections, with no Front-Cover Texts, and with no Back-Cover
       Texts.  A copy of the license is included in the section entitled "GNU
       Free Documentation License".