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AS(1)

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NAME    [Toc]    [Back]

       AS - the portable GNU assembler.

SYNOPSIS    [Toc]    [Back]

       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:
	  [-mcpu]
	  [-mdebug | -no-mdebug]
	  [-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-fromat]
	  [-mthumb]
	  [-EB|-EL]
	  [-mapcs-32|-mapcs-26|-mapcs-float|
	   -mapcs-reentrant]
	  [-mthumb-interwork] [-moabi] [-k]

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

       Target D10V options:
	  [-O]

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

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

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

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

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

       Target M68HC11 options:
	  [-m68hc11|-m68hc12]
	  [--force-long-branchs] [--short-branchs]
	  [--strict-direct-mode] [--print-insn-syntax]
	  [--print-opcodes] [--generate-example]

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

       Target MIPS options:
	  [-nocpp] [-EL] [-EB] [-G num] [-mcpu=CPU ]
	  [-mips1] [-mips2] [-mips3] [-mips4] [-mips5]
	  [-mips32] [-mips64]
	  [-m4650] [-no-m4650]
	  [--trap] [--break] [-n]
	  [--emulation=name ]

       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]

DESCRIPTION    [Toc]    [Back]

       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
       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 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 (version 2), 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  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    [Toc]    [Back]

       -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  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).

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

       --gdwarf2
	   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  This option is accepted but has no effect on the TARGET family.

       -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[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.

       -mthumb
	   Enable Thumb only instruction decoding.

       -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 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  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
	   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 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  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
       -mips64
	   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=CPU
	   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  information  or  store  symbol  table  information,  and
	   default endianness.	The available configuration names are: mipsec-
	   off,  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 ALSO    [Toc]    [Back]

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

COPYRIGHT    [Toc]    [Back]

       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".



3rd Berkeley Distribution	  2002-04-18				 AS(1)
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