as Manual Page

NAME
       AS - the portable GNU assembler.

SYNOPSIS
       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 ]
        [ -marc[5|6|7|8] ]
        [ -EB | -EL ]
        [ -m[arm]1 | -m[arm]2 | -m[arm]250 | -m[arm]3 |
          -m[arm]6 | -m[arm]60 | -m[arm]600 | -m[arm]610 |
          -m[arm]620 | -m[arm]7[t][[d]m[i]][fe] | -m[arm]70 |
          -m[arm]700 | -m[arm]710[c] | -m[arm]7100 |
          -m[arm]7500 | -m[arm]8 | -m[arm]810 | -m[arm]9 |
          -m[arm]920 | -m[arm]920t | -m[arm]9tdmi |
          -mstrongarm | -mstrongarm110 | -mstrongarm1100 ]
        [ -m[arm]v2 | -m[arm]v2a | -m[arm]v3 | -m[arm]v3m |
          -m[arm]v4 | -m[arm]v4t | -m[arm]v5 | -[arm]v5t |
          -[arm]v5te ]
        [ -mthumb | -mall ]
        [ -mfpa10 | -mfpa11 | -mfpe-old | -mno-fpu ]
        [ -EB | -EL ]
        [ -mapcs-32 | -mapcs-26 | -mapcs-float |
          -mapcs-reentrant ]
        [ -mthumb-interwork ] [ -moabi ] [ -k ]
        [ -O ]
        [ -O | -n | -N ]
        [ -mb | -me ]
        [ -Av6 | -Av7 | -Av8 | -Asparclet | -Asparclite
          -Av8plus | -Av8plusa | -Av9 | -Av9a ]
        [ -xarch=v8plus | -xarch=v8plusa ] [ -bump ]
        [ -32 | -64 ]
        [ -ACA | -ACA_A | -ACB | -ACC | -AKA | -AKB |
          -AKC | -AMC ]
        [ -b ] [ -no-relax ]
        [ --m32rx | --[no-]warn-explicit-parallel-conflicts |
          --W[n]p ]
        [ -l ] [ -m68000 | -m68010 | -m68020 | ... ]
        [ -jsri2bsr ] [ -sifilter ] [ -relax ]
        [ -mcpu=[210|340] ]
        [ -m68hc11 | -m68hc12 ]
        [ --force-long-branchs ] [ --short-branchs ]
        [ --strict-direct-mode ] [ --print-insn-syntax ]
        [ --print-opcodes ] [ --generate-example ]
        [ -nocpp ] [ -EL ] [ -EB ] [ -G num ] [ -mcpu=CPU ]
        [ -mips1 ] [ -mips2 ] [ -mips3 ] [ -mips4 ] [ -mips5 ]
        [ -mips32 ] [ -mips64 ]
        [ -m4650 ] [ -no-m4650 ]
        [ --trap ] [ --break ]
        [ --emulation=name ]
        [ -- | files ... ]

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  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
       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  hap-
       pen  when   a  compiler runs `as' automatically.  Warnings
       report an assumption made so that `as' could  keep  assem-
       bling a flawed program; errors report a grave problem that
       stops the assembly.

       If you are invoking `as' via the GNU C  compiler  (version
       2),  you  can use the -Wa option to pass arguments through
       to the assembler.  The assembler arguments must  be  sepa-
       rated  from each other (and the -Wa) by commas.  For exam-
       ple:

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

       This passes two options to the  assembler:  -alh  (emit  a
       listing to standard output with with high-level and assem-
       bly 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  pre-
       cisely  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.

       `-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).

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

       `--gdwarf2'
           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.

       `--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'
           This option is accepted but has no effect on the  TAR-
           GET family.

       `-L'

       `--keep-locals'
           Keep  (in  the symbol table) local symbols.  On tradi-
           tional 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 dis-
           played 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[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.

       `-m[arm][1|2|3|6|7|8|9][...] '
           Specify which ARM processor variant is the target.

       `-m[arm]v[2|2a|3|3m|4|4t|5|5t]'
           Specify which ARM architecture variant is used by  the
           target.

       `-mthumb | -mall'
           Enable or disable Thumb only instruction decoding.

       `-mfpa10 | -mfpa11 | -mfpe-old | -mno-fpu'
           Select  which  Floating Point architecture is the tar-
           get.

       `-mapcs-32 | -mapcs-26 | -mapcs-float | -mapcs-reentrant |
       -moabi'
           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 inter-
           working 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 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 Mitsubishi M32R series.

       `--m32rx'
           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'
           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 exten-
           sions.

       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'
           Specify what processor is the target.  The default  is
           defined  by the configuration option when building the
           assembler.

       `--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  config-
       ured 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  architec-
           ture.

       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'

       `-mips32'
           Generate code for a particular  MIPS  Instruction  Set
           Architecture  level.   -mips1 corresponds to the R2000
           and R3000 processors, -mips2 to the  R6000  processor,
           and  -mips3  to the R4000 processor.  -mips5, -mips32,
           and -mips64 correspond to generic MIPS V, MIPS32,  and
           MIPS64 ISA processors, respectively.



       `-m4650'

       `-no-m4650'
           Generate code for the MIPS R4650 chip.  This tells the
           assembler to accept the mad and madu instruction,  and
           to  not  schedule  nop instructions around accesses to
           the HI and LO registers.   -no-m4650  turns  off  this
           option.

       `-mcpu=PU'
           Generate  code  for  a  particular  MIPS  cpu.   It is
           exactly equivalent to -mcpu,  except  that  there  are
           more value of cpu understood.

       `--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  infor-
           mation  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 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-
           cessors.

       `-nocpp'
           `as' ignores this option.  It is accepted for compati-
           bility 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.

       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 overrid-
           den 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 con-
           trols which instructions can be assembled.

       `-EB'
           Assemble for a big endian target.

       `-EL'
           Assemble for a little endian target.

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 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".