gas/README - third_party/binutils-gdb - Git at Google

 		README for GAS

 A number of things have changed since version 1 and the wonderful
 world of gas looks very different.  There's still a lot of irrelevant
 garbage lying around that will be cleaned up in time.  Documentation
 is scarce, as are logs of the changes made since the last gas release.
 My apologies, and I'll try to get something useful.

 Unpacking and Installation - Summary
 ====================================

 See ../binutils/README.

 To build just the assembler, make the target all-gas.

 Documentation
 =============

 The GAS release includes texinfo source for its manual, which can be processed
 into `info' or `dvi' forms.

 The DVI form is suitable for printing or displaying; the commands for doing
 this vary from system to system.  On many systems, `lpr -d' will print a DVI
 file.  On others, you may need to run a program such as `dvips' to convert the
 DVI file into a form your system can print.

 If you wish to build the DVI file, you will need to have TeX installed on your
 system.  You can rebuild it by typing:

 	cd gas/doc
 	make as.dvi

 The Info form is viewable with the GNU Emacs `info' subsystem, or the
 stand-alone `info' program, available as part of the GNU Texinfo distribution.
 To build the info files, you will need the `makeinfo' program.  Type:

 	cd gas/doc
 	make info

 Specifying names for hosts and targets
 ======================================

    The specifications used for hosts and targets in the `configure'
 script are based on a three-part naming scheme, but some short
 predefined aliases are also supported.  The full naming scheme encodes
 three pieces of information in the following pattern:

      ARCHITECTURE-VENDOR-OS

    For example, you can use the alias `sun4' as a HOST argument or in a
 `--target=TARGET' option.  The equivalent full name is
 `sparc-sun-sunos4'.

    The `configure' script accompanying GAS does not provide any query
 facility to list all supported host and target names or aliases.
 `configure' calls the Bourne shell script `config.sub' to map
 abbreviations to full names; you can read the script, if you wish, or
 you can use it to test your guesses on abbreviations--for example:

      % sh config.sub i386v
      i386-unknown-sysv
      % sh config.sub i786v
      Invalid configuration `i786v': machine `i786v' not recognized


 `configure' options
 ===================

    Here is a summary of the `configure' options and arguments that are
 most often useful for building GAS.  `configure' also has several other
 options not listed here.

      configure [--help]
                [--prefix=DIR]
                [--srcdir=PATH]
                [--host=HOST]
                [--target=TARGET]
                [--with-OPTION]
                [--enable-OPTION]

 You may introduce options with a single `-' rather than `--' if you
 prefer; but you may abbreviate option names if you use `--'.

 `--help'
      Print a summary of the options to `configure', and exit.

 `-prefix=DIR'
      Configure the source to install programs and files under directory
      `DIR'.

 `--srcdir=PATH'
      Look for the package's source code in directory DIR.  Usually
      `configure' can determine that directory automatically.

 `--host=HOST'
      Configure GAS to run on the specified HOST.  Normally the
      configure script can figure this out automatically.

      There is no convenient way to generate a list of all available
      hosts.

 `--target=TARGET'
      Configure GAS for cross-assembling programs for the specified
      TARGET.  Without this option, GAS is configured to assemble .o files
      that run on the same machine (HOST) as GAS itself.

      There is no convenient way to generate a list of all available
      targets.

 `--enable-OPTION'
      These flags tell the program or library being configured to
      configure itself differently from the default for the specified
      host/target combination.  See below for a list of `--enable'
      options recognized in the gas distribution.

 `configure' accepts other options, for compatibility with configuring
 other GNU tools recursively; but these are the only options that affect
 GAS or its supporting libraries.

 The `--enable' options recognized by software in the gas distribution are:

 `--enable-targets=...'
      This causes one or more specified configurations to be added to those for
      which BFD support is compiled.  Currently gas cannot use any format other
      than its compiled-in default, so this option is not very useful.

 `--enable-bfd-assembler'
      This causes the assembler to use the new code being merged into it to use
      BFD data structures internally, and use BFD for writing object files.
      For most targets, this isn't supported yet.  For most targets where it has
      been done, it's already the default.  So generally you won't need to use
      this option.

 Compiler Support Hacks
 ======================

 On a few targets, the assembler has been modified to support a feature
 that is potentially useful when assembling compiler output, but which
 may confuse assembly language programmers.  If assembler encounters a
 .word pseudo-op of the form symbol1-symbol2 (the difference of two
 symbols), and the difference of those two symbols will not fit in 16
 bits, the assembler will create a branch around a long jump to
 symbol1, and insert this into the output directly before the next
 label: The .word will (instead of containing garbage, or giving an
 error message) contain (the address of the long jump)-symbol2.  This
 allows the assembler to assemble jump tables that jump to locations
 very far away into code that works properly.  If the next label is
 more than 32K away from the .word, you lose (silently); RMS claims
 this will never happen.  If the -K option is given, you will get a
 warning message when this happens.


 REPORTING BUGS IN GAS
 =====================

 Bugs in gas should be reported to:

    bug-binutils@gnu.org.

 They may be cross-posted to gcc-bugs@gnu.org if they affect the use of
 gas with gcc.  They should not be reported just to gcc-bugs, since not
 all of the maintainers read that list.

 See ../binutils/README for what we need in a bug report.

 Copyright (C) 2012-2016 Free Software Foundation, Inc.

 Copying and distribution of this file, with or without modification,
 are permitted in any medium without royalty provided the copyright
 notice and this notice are preserved.
	README for GAS

	A number of things have changed since version 1 and the wonderful
	world of gas looks very different. There's still a lot of irrelevant
	garbage lying around that will be cleaned up in time. Documentation
	is scarce, as are logs of the changes made since the last gas release.
	My apologies, and I'll try to get something useful.

	Unpacking and Installation - Summary
	====================================

	See ../binutils/README.

	To build just the assembler, make the target all-gas.

	Documentation
	=============

	The GAS release includes texinfo source for its manual, which can be processed
	into `info' or `dvi' forms.

	The DVI form is suitable for printing or displaying; the commands for doing
	this vary from system to system. On many systems, `lpr -d' will print a DVI
	file. On others, you may need to run a program such as `dvips' to convert the
	DVI file into a form your system can print.

	If you wish to build the DVI file, you will need to have TeX installed on your
	system. You can rebuild it by typing:

	cd gas/doc
	make as.dvi

	The Info form is viewable with the GNU Emacs `info' subsystem, or the
	stand-alone `info' program, available as part of the GNU Texinfo distribution.
	To build the info files, you will need the `makeinfo' program. Type:

	cd gas/doc
	make info

	Specifying names for hosts and targets
	======================================

	The specifications used for hosts and targets in the `configure'
	script are based on a three-part naming scheme, but some short
	predefined aliases are also supported. The full naming scheme encodes
	three pieces of information in the following pattern:

	ARCHITECTURE-VENDOR-OS

	For example, you can use the alias `sun4' as a HOST argument or in a
	`--target=TARGET' option. The equivalent full name is
	`sparc-sun-sunos4'.

	The `configure' script accompanying GAS does not provide any query
	facility to list all supported host and target names or aliases.
	`configure' calls the Bourne shell script `config.sub' to map
	abbreviations to full names; you can read the script, if you wish, or
	you can use it to test your guesses on abbreviations--for example:

	% sh config.sub i386v
	i386-unknown-sysv
	% sh config.sub i786v
	Invalid configuration `i786v': machine `i786v' not recognized


	`configure' options
	===================

	Here is a summary of the `configure' options and arguments that are
	most often useful for building GAS. `configure' also has several other
	options not listed here.

	configure [--help]
	[--prefix=DIR]
	[--srcdir=PATH]
	[--host=HOST]
	[--target=TARGET]
	[--with-OPTION]
	[--enable-OPTION]

	You may introduce options with a single `-' rather than `--' if you
	prefer; but you may abbreviate option names if you use `--'.

	`--help'
	Print a summary of the options to `configure', and exit.

	`-prefix=DIR'
	Configure the source to install programs and files under directory
	`DIR'.

	`--srcdir=PATH'
	Look for the package's source code in directory DIR. Usually
	`configure' can determine that directory automatically.

	`--host=HOST'
	Configure GAS to run on the specified HOST. Normally the
	configure script can figure this out automatically.

	There is no convenient way to generate a list of all available
	hosts.

	`--target=TARGET'
	Configure GAS for cross-assembling programs for the specified
	TARGET. Without this option, GAS is configured to assemble .o files
	that run on the same machine (HOST) as GAS itself.

	There is no convenient way to generate a list of all available
	targets.

	`--enable-OPTION'
	These flags tell the program or library being configured to
	configure itself differently from the default for the specified
	host/target combination. See below for a list of `--enable'
	options recognized in the gas distribution.

	`configure' accepts other options, for compatibility with configuring
	other GNU tools recursively; but these are the only options that affect
	GAS or its supporting libraries.

	The `--enable' options recognized by software in the gas distribution are:

	`--enable-targets=...'
	This causes one or more specified configurations to be added to those for
	which BFD support is compiled. Currently gas cannot use any format other
	than its compiled-in default, so this option is not very useful.

	`--enable-bfd-assembler'
	This causes the assembler to use the new code being merged into it to use
	BFD data structures internally, and use BFD for writing object files.
	For most targets, this isn't supported yet. For most targets where it has
	been done, it's already the default. So generally you won't need to use
	this option.

	Compiler Support Hacks
	======================

	On a few targets, the assembler has been modified to support a feature
	that is potentially useful when assembling compiler output, but which
	may confuse assembly language programmers. If assembler encounters a
	.word pseudo-op of the form symbol1-symbol2 (the difference of two
	symbols), and the difference of those two symbols will not fit in 16
	bits, the assembler will create a branch around a long jump to
	symbol1, and insert this into the output directly before the next
	label: The .word will (instead of containing garbage, or giving an
	error message) contain (the address of the long jump)-symbol2. This
	allows the assembler to assemble jump tables that jump to locations
	very far away into code that works properly. If the next label is
	more than 32K away from the .word, you lose (silently); RMS claims
	this will never happen. If the -K option is given, you will get a
	warning message when this happens.


	REPORTING BUGS IN GAS
	=====================

	Bugs in gas should be reported to:

	bug-binutils@gnu.org.

	They may be cross-posted to gcc-bugs@gnu.org if they affect the use of
	gas with gcc. They should not be reported just to gcc-bugs, since not
	all of the maintainers read that list.

	See ../binutils/README for what we need in a bug report.

	Copyright (C) 2012-2016 Free Software Foundation, Inc.

	Copying and distribution of this file, with or without modification,
	are permitted in any medium without royalty provided the copyright
	notice and this notice are preserved.