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The result of running etc/update-copyright.py --this-year, fixing all the files whose mode is changed by the script, plus a build with --enable-maintainer-mode --enable-cgen-maint=yes, then checking out */po/*.pot which we don't update frequently. The copy of cgen was with commit d1dd5fcc38ead reverted as that commit breaks building of bfp opcodes files.
167 lines
6.0 KiB
Plaintext
167 lines
6.0 KiB
Plaintext
README for GAS
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A number of things have changed since version 1 and the wonderful
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world of gas looks very different. There's still a lot of irrelevant
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garbage lying around that will be cleaned up in time. Documentation
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is scarce, as are logs of the changes made since the last gas release.
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My apologies, and I'll try to get something useful.
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Unpacking and Installation - Summary
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====================================
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See ../binutils/README.
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To build just the assembler, make the target all-gas.
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Documentation
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=============
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The GAS release includes texinfo source for its manual, which can be processed
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into `info' or `dvi' forms.
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The DVI form is suitable for printing or displaying; the commands for doing
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this vary from system to system. On many systems, `lpr -d' will print a DVI
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file. On others, you may need to run a program such as `dvips' to convert the
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DVI file into a form your system can print.
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If you wish to build the DVI file, you will need to have TeX installed on your
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system. You can rebuild it by typing:
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cd gas/doc
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make as.dvi
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The Info form is viewable with the GNU Emacs `info' subsystem, or the
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stand-alone `info' program, available as part of the GNU Texinfo distribution.
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To build the info files, you will need the `makeinfo' program. Type:
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cd gas/doc
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make info
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Specifying names for hosts and targets
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======================================
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The specifications used for hosts and targets in the `configure'
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script are based on a three-part naming scheme, but some short
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predefined aliases are also supported. The full naming scheme encodes
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three pieces of information in the following pattern:
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ARCHITECTURE-VENDOR-OS
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For example, you can use the alias `sun4' as a HOST argument or in a
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`--target=TARGET' option. The equivalent full name is
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`sparc-sun-sunos4'.
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The `configure' script accompanying GAS does not provide any query
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facility to list all supported host and target names or aliases.
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`configure' calls the Bourne shell script `config.sub' to map
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abbreviations to full names; you can read the script, if you wish, or
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you can use it to test your guesses on abbreviations--for example:
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% sh config.sub i386v
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i386-unknown-sysv
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% sh config.sub i786v
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Invalid configuration `i786v': machine `i786v' not recognized
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`configure' options
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===================
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Here is a summary of the `configure' options and arguments that are
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most often useful for building GAS. `configure' also has several other
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options not listed here.
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configure [--help]
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[--prefix=DIR]
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[--srcdir=PATH]
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[--host=HOST]
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[--target=TARGET]
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[--with-OPTION]
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[--enable-OPTION]
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You may introduce options with a single `-' rather than `--' if you
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prefer; but you may abbreviate option names if you use `--'.
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`--help'
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Print a summary of the options to `configure', and exit.
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`-prefix=DIR'
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Configure the source to install programs and files under directory
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`DIR'.
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`--srcdir=PATH'
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Look for the package's source code in directory DIR. Usually
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`configure' can determine that directory automatically.
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`--host=HOST'
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Configure GAS to run on the specified HOST. Normally the
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configure script can figure this out automatically.
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There is no convenient way to generate a list of all available
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hosts.
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`--target=TARGET'
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Configure GAS for cross-assembling programs for the specified
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TARGET. Without this option, GAS is configured to assemble .o files
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that run on the same machine (HOST) as GAS itself.
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There is no convenient way to generate a list of all available
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targets.
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`--enable-OPTION'
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These flags tell the program or library being configured to
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configure itself differently from the default for the specified
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host/target combination. See below for a list of `--enable'
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options recognized in the gas distribution.
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`configure' accepts other options, for compatibility with configuring
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other GNU tools recursively; but these are the only options that affect
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GAS or its supporting libraries.
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The `--enable' options recognized by software in the gas distribution are:
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`--enable-targets=...'
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This causes one or more specified configurations to be added to those for
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which BFD support is compiled. Currently gas cannot use any format other
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than its compiled-in default, so this option is not very useful.
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`--enable-bfd-assembler'
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This causes the assembler to use the new code being merged into it to use
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BFD data structures internally, and use BFD for writing object files.
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For most targets, this isn't supported yet. For most targets where it has
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been done, it's already the default. So generally you won't need to use
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this option.
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Compiler Support Hacks
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======================
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On a few targets, the assembler has been modified to support a feature
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that is potentially useful when assembling compiler output, but which
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may confuse assembly language programmers. If assembler encounters a
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.word pseudo-op of the form symbol1-symbol2 (the difference of two
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symbols), and the difference of those two symbols will not fit in 16
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bits, the assembler will create a branch around a long jump to
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symbol1, and insert this into the output directly before the next
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label: The .word will (instead of containing garbage, or giving an
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error message) contain (the address of the long jump)-symbol2. This
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allows the assembler to assemble jump tables that jump to locations
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very far away into code that works properly. If the next label is
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more than 32K away from the .word, you lose (silently); RMS claims
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this will never happen. If the -K option is given, you will get a
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warning message when this happens.
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REPORTING BUGS IN GAS
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=====================
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Bugs in gas should be reported to:
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https://sourceware.org/bugzilla/
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See ../binutils/README for what we need in a bug report.
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Copyright (C) 2012-2022 Free Software Foundation, Inc.
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Copying and distribution of this file, with or without modification,
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are permitted in any medium without royalty provided the copyright
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notice and this notice are preserved.
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