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as(1)			     GNU Development Tools			 as(1)

       GNU as -	the portable GNU assembler.

       as [-a[dhlns][=file]] [-D] [--defsym SYM=VAL] [-f] [--gstabs] [-I path]
       [-K] [-L] [-M | --mri] [-o objfile] [-R]	[--traditional-format] [-v]
       [-w] [--	| files...]

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

       m680x0-only options:
       [-l] [-mc68000|-mc68010|-mc68020]

       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 en-
       vironment  when	you  use it on another architecture.  Each version has
       much in common with the others, including object	file formats, most as-
       sembler directives (often called	pseudo-ops) and	assembler syntax.

       For  information	 on the	syntax and pseudo-ops used by GNU as, see `as'
       entry in	info (or the manual Using as: The GNU Assembler).

       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 as-
       semble correctly	everything that	 the  native  assembler	 would.	  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.)

       If  as  is  given 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.

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

       -a     Turn  on	assembly  listings.   There are	various	suboptions.  d
	      omits debugging directives.  h includes the  high	 level	source
	      code;  this  is  only available if the source file can be	found,
	      and the code was compiled	with -g.  l includes an	assembly list-
	      ing.  n omits forms processing.  s includes a symbol listing.  =
	      file sets	the listing file name; this must be  the  last	subop-
	      tion.  The default suboptions are	hls.

       -D     This option is accepted only for script compatibility with calls
	      to other assemblers; it has no effect on as.

       --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  oc-
	      tal value.

       -f     ``fast''--skip preprocessing (assume source is compiler output).

       -I path
	      Add path to the search list for .include directives.

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

       -K     Issue warnings when difference tables altered for	long displace-

       -L     Keep (in symbol table) local symbols, starting with `L'

       -M, --mri
	      Assemble in MRI compatibility mode.

       -o objfile
	      Name the object-file output from as

       -R     Fold data	section	into text section

	      Use same format as native	assembler, when	possible.

       -v     Announce as version

       -W     Suppress warning messages

       -- | files...
	      Source files to assemble,	or standard input (--)

       -Avar  (When configured for Intel 960.)	Specify	which variant  of  the
	      960 architecture is the target.

       -b     (When configured for Intel 960.)	Add code to collect statistics
	      about branches taken.

	      (When configured for Intel  960.)	  Do  not  alter  compare-and-
	      branch instructions for long displacements; error	if necessary.

       -l     (When configured for Motorola 68000).
	      Shorten  references to undefined symbols,	to one word instead of

	      (When configured for Motorola 68000).
	      Specify what processor in	the 68000 family is  the  target  (de-
	      fault 68020)

       Options	may be in any order, and may be	before,	after, or between file
       names.  The order of file names is significant.

       `--' (two hyphens) by itself names the standard input file  explicitly,
       as one of the files for as to assemble.

       Except  for  `--'  any  command line argument that begins with a	hyphen
       (`-') is	an option.  Each option	changes	the behavior of	as.  No	option
       changes	the  way another option	works.	An option is a `-' followed by
       one or more letters; the	case of	the letter is important.   All options
       are optional.

       The `-o'	option expects exactly one file	name to	follow.	 The file name
       may either immediately follow  the  option's  letter  (compatible  with
       older  assemblers)  or  it  may be the next command argument (GNU stan-

       These two command lines are equivalent:
       as  -o  my-object-file.o	 mumble.s
       as  -omy-object-file.o  mumble.s

       `as' entry in info; Using as: The GNU Assembler;	gcc(1),	ld(1).

       Copyright (c) 1991, 1992	Free Software Foundation, Inc.

       Permission is granted to	make and distribute verbatim  copies  of  this
       manual  provided	 the  copyright	 notice	and this permission notice are
       preserved on all	copies.

       Permission is granted to	copy and distribute modified versions of  this
       manual under the	conditions for verbatim	copying, provided that the en-
       tire resulting derived work is distributed under	the terms of a permis-
       sion notice identical to	this one.

       Permission  is granted to copy and distribute translations of this man-
       ual into	another	language, under	the above conditions for modified ver-
       sions,  except  that this permission notice may be included in transla-
       tions approved by the Free Software Foundation instead of in the	origi-
       nal English.

cygnus support			 29 March 1996				 as(1)


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