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       as [-a[cdhlns][=file]] [-D] [--defsym sym=val]
        [-f] [--gstabs] [--gdwarf2] [--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:
          [-mdebug | -no-mdebug]
          [-relax] [-g] [-Gsize]
          [-F] [-32addr]

       Target ARC options:

       Target ARM options:
          [-mthumb-interwork] [-moabi] [-k]

       Target CRIS options:
          [--underscore | --no-underscore]
          [--pic] [-N]
          [--emulation=criself | --emulation=crisaout]

       Target D10V options:

       Target D30V options:

       Target i386 options:
          [--32|--64] [-n]

       Target i960 options:
          [-b] [-no-relax]

       Target IP2K options:
          [--print-opcodes] [--generate-example]

       Target MCORE options:
          [-jsri2bsr] [-sifilter] [-relax]

       Target MIPS options:
          [-nocpp] [-EL] [-EB] [-n] [-O[optimization level]]
          [-g[debug level]] [-G num] [-KPIC] [-call_shared]
          [-non_shared] [-xgot] [--membedded-pic]
          [-mabi=ABI] [-32] [-n32] [-64] [-mfp32] [-mgp32]
          [-march=CPU] [-mtune=CPU] [-mips1] [-mips2]
          [-mips3] [-mips4] [-mips5] [-mips32] [-mips32r2]
          [-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]

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

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

       Target picoJava options:

       Target PowerPC options:
          [-mcom|-many|-maltivec] [-memb]

       Target SPARC options:
          [-xarch=v8plus|-xarch=v8plusa] [-bump]

       with  the  others,  including  object  file  formats, most
       assembler directives (often called pseudo-ops) and  assem­
       bler syntax.

       as is primarily intended to assemble the output of the GNU
       C compiler  for use by the linker .   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  pro­
       gram.  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

       as  may  write warnings and error messages to the standard
       error file (usually your terminal).  This should not  hap­
       pen  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
           -ah include high-level source

           -al include assembly

           -am include macro expansions

           -an omit forms processing

           -as include symbols

               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.

       -D  Ignored.  This option is accepted for script  compati­
           bility 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).

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

           Generate  DWARF2 debugging information for each assem­
           bler 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.

           Print a summary of the command line options and  exit.

           Print  a  summary  of  all target specific options and

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

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

           Set the maximum width of an input source line, as dis­
           played in a listing, to number bytes.

           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.

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

           Remove local absolute symbols from the outgoing symbol

           Print the as version.

           Print the as version and exit.

           Suppress warning messages.

           Treat warnings as errors.

           Don't  suppress  warning  messages  or  treat  them as

       -w  Ignored.

       -x  Ignored.

       -Z  Generate an object file even after errors.

       -- | files ...

           Specify which ARM processor variant is the target.

           Specify  which ARM architecture variant is used by the

           Select which Floating Point architecture is  the  tar­

           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)

           Specify that the code has been generated  with  inter­
           working 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

       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

       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

           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.

           Specify which processor in the M32R family is the tar­
           get.  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 par­
           allel 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 tar­
           get.  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  copro­
           cessor  for  68020,  68030,  and  cpu32.  Although the
           basic 68000 is not compatible with the 68881, a combi­
           nation  of the two can be specified, since it's possi­
           ble 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

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

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

       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

           Specify to use the 16-bit integer ABI.

           Specify to use the 32-bit integer ABI.

           Specify to use the 32-bit double ABI.

           Specify to use the 64-bit double ABI.

           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.

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

       -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.

           Warn when the assembler switches to another  architec­

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

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

           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.

           Generate code for a particular MIPS cpu.

           Schedule and tune for a particular MIPS cpu.

           Cause  nops to be inserted if the read of the destina­
           tion register of an mfhi or mflo instruction occurs in
           the following two instructions.

           Cause  stabs-style  debugging  output  to  go  into an
           ECOFF-style .mdebug section instead  of  the  standard
           ELF .stabs sections.

           The  register sizes are normally inferred from the ISA
           and ABI, but these flags force a certain group of reg­
           isters  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 regis­

           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.

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

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

           The  --no-construct-floats  option  disables  the con­
           struction of double width floating point constants  by
           loading  the two halves of the value into the two sin­
           gle width floating point registers that  make  up  the
           double  width register.  By default --construct-floats
           is selected, allowing construction of  these  floating
           the b or l in the name.  Using -EB or -EL  will  over­
           ride the endianness selection in any case.

           This  option is currently supported only when the pri­
           mary target as is configured for  is  a  MIPS  ELF  or
           ECOFF target.  Furthermore, the primary target or oth­
           ers specified with --enable-targets=... at  configura­
           tion  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 configura­
           tions, with more fine-grained control over the  assem­
           bler's  behavior,  and will be supported for more pro­

           as ignores this option.  It is accepted  for  compati­
           bility with the native tools.

           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

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

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

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

           Alter jump instructions for long displacements.

       --density | --no-density
           Enable or disable use of instructions from the  Xtensa
           code  density option.  This is enabled by default when
           the Xtensa processor supports the code density option.

       --relax | --no-relax
           Enable  or  disable  instruction  relaxation.  This is
           enabled by default.  Note: In the current  implementa­
           tion,  these  options  also  control whether assembler
           optimizations  are  performed,  making  these  options
           equivalent to --generics and --no-generics.

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

       --text-section-literals | --no-text-section-literals
           With --text-section-literals, literal pools are inter­
           spersed  in  the  text  section.    The   default   is
           --no-text-section-literals, which places literals in a
           separate section in the output file.

       --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.


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


       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  Documenta­
       tion  License,  Version 1.1 or any later version published
       by the Free Software Foundation; with  no  Invariant  Sec­
       tions,  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''.

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