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NAME

       AS - the portable GNU assembler.

SYNOPSIS

       as [-a[cdhlns][=file]] [--alternate] [-D]
        [--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] [--statistics] [-v]
        [-version] [--version] [-W] [--warn] [--fatal-warnings]
        [-w] [-x] [-Z] [--target-help] [target-options]
        [--files ...]

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

       Target ARC options:
          [-marc[5678]]
          [-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 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 i386 options:
          [--32--64] [-n]

       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]
          [-mlembe]
          [-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 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-branchs] [--short-branchs]
          [--strict-direct-mode] [--print-insn-syntax]
          [--print-opcodes] [--generate-example]

       Target MCORE options:
          [-jsri2bsr] [-sifilter] [-relax]
          [-mcpu=[210340]]

       Target MIPS options:
          [-nocpp] [-EL] [-EB] [-O[optimization level]]
          [-g[debug level]] [-G num] [-KPIC] [-call_shared]
          [-non_shared] [-xgot]
          [-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]
          [-mfix7000] [-mno-fix7000]
          [-mips16] [-no-mips16]
          [-mips3d] [-no-mips3d]
          [-mdmx] [-no-mdmx]
          [-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-mbooke32-mbooke64]
          [-mcom-many-maltivec] [-memb]
          [-mregnames-mno-regnames]
          [-mrelocatable-mrelocatable-lib]
          [-mlittle-mlittle-endian-mbig-mbig-endian]
          [-msolaris-mno-solaris]

       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 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

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

           -ac omit false conditionals

           -ad omit debugging directives

           -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, see @ref{Altmacro,,".altmacro"}.

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

       --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.

       -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.  On traditional a.out
           systems these start with L, but different  systems  have  different
           local label prefixes.

       --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.

       --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[5678]
           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.

       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 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
       @ref{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-branchs
           Relative  branches  are  turned  into  absolute ones. This concerns
           conditional branches, unconditional branches and branches to a  sub
           routine.

       -S--short-branchs
           Do  not turn relative branchs 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.

       -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.

       --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=[210340]
           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.

       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.

SEE ALSO

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

COPYRIGHT

       Copyright (C) 1991, 92, 93, 94, 95, 96, 97, 98, 99,  2000,  2001,  2002
       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  1.1  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’’.