--*- text -*-
+ README for GAS
- README for GAS 2.2.1 release
- [cribbed largely from GDB's README file]
-
-This is version 2.2.1 of the GNU assembler.
-
-A number of things have changed 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.
+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
====================================
-In this release, the GNU assembler ("gas") sources, the generic GNU include
-files, the BFD ("binary file description") library, and other libraries all
-have directories of their own underneath the gas-2.2.1 directory. The idea is
-that a variety of GNU tools can share a common copy of these things.
-Configuration scripts and makefiles exist to cruise up and down this directory
-tree and automatically build all the pieces in the right order.
-
-When you unpack the gas-2.2.1.tar.z file, you'll find a directory called
-`gas-2.2.1'. To build GAS, you can just do:
-
- cd gas-2.2.1
- ./configure
- make
- cp gas/as.new /usr/local/bin/as (or whereever)
-
-This will configure and build all the libraries as well as GAS. If
-`configure' can't determine your system type, specify one as its argument,
-e.g., sun4 or decstation.
-
-If you get compiler warnings during this stage, see the `Reporting Bugs'
-section below; there are a few known problems.
+See ../binutils/README.
-GAS can be used as a cross-assembler, running on a machine of one type while
-producing object files for a machine of another type. See below.
+To build just the assembler, make the target all-gas.
Documentation
=============
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-2.2.1/gas/doc
+ cd gas/doc
make as.dvi
The Info form is viewable with the GNU Emacs `info' subsystem, or the
standalone `info' program, available as part of the GNU Texinfo distribution.
To build the info files, you will need the `makeinfo' program. Type:
- cd gas-2.2.1/gas/doc
+ cd gas/doc
make info
-Installing GAS
-==============
-
-GAS comes with a `configure' script that automates the process of preparing
-GAS for installation; you can then use `make' to build the program.
-
-The GAS distribution includes all the source code you need for GAS in a single
-directory, the name of which is usually composed by appending the version
-number to `gas'.
-
-The simplest way to configure and build GAS is to run `configure' from the
-`gas-VERSION-NUMBER' source directory, which in this example is the `gas-2.2.1'
-directory.
-
-First switch to the `gas-VERSION-NUMBER' source directory if you are not
-already in it; then run `configure'. Pass the identifier for the platform on
-which GAS will run as an argument. For example:
-
- cd gas-2.2.1
- ./configure HOST
- make
-
-where HOST is an identifier such as `sun4' or `decstation', that identifies
-the platform where GAS will run.
-
-Running `configure HOST' followed by `make' builds the `bfd', `opcode', and
-`libiberty' libraries, then `gas' itself. (Exception: For VMS, the `bfd'
-library is not used.) The configured source files, and the binaries, are left
-in the corresponding source directories.
-
-The `configure' program is a Bourne-shell (`/bin/sh') script; if your system
-does not recognize this automatically when you run a different shell, you may
-need to run `sh' on it explicitly:
-
- sh configure HOST
-
-If you run `configure' from a directory that contains source
-directories for multiple libraries or programs, such as the `gas-2.2.1'
-source directory for version 2.2.1, `configure' creates configuration
-files for every directory level underneath (unless you tell it not to,
-with the `--norecursion' option).
-
-You can run the `configure' script from any of the subordinate directories in
-the GAS distribution, if you only want to configure that subdirectory; but be
-sure to specify a path to it.
-
-For example, with version 2.2.1, type the following to configure only the `bfd'
-subdirectory:
-
- cd gas-2.2.1/bfd
- ../configure HOST
-
-Compiling GAS in another directory
-==================================
-
- If you want to run GAS versions for several host or target machines,
-you need a different `gas' compiled for each combination of host and
-target. `configure' is designed to make this easy by allowing you to
-generate each configuration in a separate subdirectory, rather than in
-the source directory. If your `make' program handles the `VPATH'
-feature (GNU `make' does), running `make' in each of these directories
-builds the `gas' program specified there.
-
- To build `gas in a separate directory, run `configure' with the
-`--srcdir' option to specify where to find the source. (You also need
-to specify a path to find `configure' itself from your working
-directory. If the path to `configure' would be the same as the
-argument to `--srcdir', you can leave out the `--srcdir' option; it
-will be assumed.)
-
- For example, with version 2.2.1, you can build GAS in a separate
-directory for a Sun 4 like this:
-
- cd gas-2.2.1
- mkdir ../gas-sun4
- cd ../gas-sun4
- ../gas-2.2.1/configure sun4
- make
-
- When `configure' builds a configuration using a remote source
-directory, it creates a tree for the binaries with the same structure
-(and using the same names) as the tree under the source directory. In
-the example, you'd find the Sun 4 library `libiberty.a' in the
-directory `gas-sun4/libiberty', and GAS itself in `gas-sun4/gas'.
-
- One popular reason to build several GAS configurations in separate
-directories is to configure GAS for cross-compiling (where GAS runs on
-one machine--the host--while debugging programs that run on another
-machine--the target). You specify a cross-debugging target by giving
-the `--target=TARGET' option to `configure'.
-
- When you run `make' to build a program or library, you must run it
-in a configured directory--whatever directory you were in when you
-called `configure' (or one of its subdirectories).
-
- The `Makefile' that `configure' generates in each source directory
-also runs recursively. If you type `make' in a source directory such
-as `gas-2.2.1' (or in a separate configured directory configured with
-`--srcdir=PATH/gas-2.2.1'), you will build all the required libraries,
-and then build GAS.
-
- When you have multiple hosts or targets configured in separate
-directories, you can run `make' on them in parallel (for example, if
-they are NFS-mounted on each of the hosts); they will not interfere
-with each other.
-
-
Specifying names for hosts and targets
======================================
% sh config.sub i786v
Invalid configuration `i786v': machine `i786v' not recognized
-`config.sub' is also distributed in the GAS source directory
-(`gas-2.2.1', for version 2.2.1).
-
`configure' options
===================
configure [--help]
[--prefix=DIR]
[--srcdir=PATH]
- [--norecursion] [--rm]
- [--target=TARGET] HOST
+ [--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'
- Display a quick summary of how to invoke `configure'.
+ 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'
- *Warning: using this option requires GNU `make', or another `make'
- that implements the `VPATH' feature.*
- Use this option to make configurations in directories separate
- from the GAS source directories. Among other things, you can use
- this to build (or maintain) several configurations simultaneously,
- in separate directories. `configure' writes configuration
- specific files in the current directory, but arranges for them to
- use the source in the directory PATH. `configure' will create
- directories under the working directory in parallel to the source
- directories below PATH.
-
-`--norecursion'
- Configure only the directory level where `configure' is executed;
- do not propagate configuration to subdirectories.
-
-`--rm'
- Remove the configuration that the other arguments specify.
+ 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
There is no convenient way to generate a list of all available
targets.
-`--with-OPTION'
- These flags tell the program or library being configured to assume the
- use of certain programs, or to otherwise configure themselves differently
- from the default for the specified host/target combination. See below
- for a list of `--with' options recognized in the gas-2.2.1 distribution.
-
-`HOST ...'
- Configure GAS to run on the specified HOST.
-
- There is no convenient way to generate a list of all available
- hosts.
+`--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 `--with' options recognized by software in the gas-2.2.1 distribution are:
+The `--enable' options recognized by software in the gas distribution are:
-`--with-minimal-bfd'
- This causes the BFD library, if it is used by the assembler, to only link
- in support for the specified target; by default, support for all targets
- known to BFD is linked in, even though the assembler generally won't
- be able to use them. This will probably be made a default, or replaced
- by a better mechanism, for gas-2.1.
+`--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.
-`--with-bfd-assembler'
+`--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. See `BFD CONVERSION' in the
- file `gas/NOTES'.
+ 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.
Supported platforms
===================
sun3
sun4
386bsd
- bsd/386?
- linux
+ bsd/386
+ delta (m68k-sysv from Motorola)
+ delta88 (m88k-sysv from Motorola)
+ GNU/linux
m68k hpux 8.0 (hpux 7.0 may be a problem)
vax bsd, ultrix, vms
hp9000s300
decstation
- iris
+ irix 4
+ irix 5
miniframe (m68k-sysv from Convergent Technologies)
i386-aix (ps/2)
+ hppa (hpux 4.3bsd, osf1)
+ AIX
+ unixware
+ sco 3.2v4.2
+ sco openserver 5.0 (a.k.a. 3.2v5.0 )
+ sparc solaris
+ ns32k (netbsd, lites)
-For cross-assemblers, I believe hosting to work on any of the machines listed
-above, plus:
-
- rs6000
- sun386i
- at least some flavors of hpux (hpux 7.0 may be a problem)
- most flavors of sysV
+I believe that gas as a cross-assembler can currently be targetted for
+most of the above hosts, plus
-I believe that gas as a cross-assembler can currently be targetted for:
-
- 386bsd
- bsd/386?
decstation-bsd (a.out format, to be used in BSD 4.4)
ebmon29k
- go32 (DOS on i386, with DJGPP)
+ go32 (DOS on i386, with DJGPP -- old a.out version)
h8/300, h8/500 (Hitachi)
- hp9000/300
i386-aix (ps/2)
i960-coff
- linux
- mips ecoff (decstation-ultrix, iris, mips magnum)
+ mips ecoff (decstation-ultrix, iris, mips magnum, mips-idt-ecoff)
+ Mitsubishi d10v and d30v
nindy960
+ powerpc EABI
+ SH (Hitachi)
sco386
- sun3
- sun4
+ TI tic30 and tic80
vax bsd or ultrix?
vms
vxworks68k
MIPS ECOFF support has been added, but GAS will not run a C-style
preprocessor. If you want that, rename your file to have a ".S" suffix, and
-run gcc on it.
-
-Support for ns32k, tahoe, i860, m88k may be suffering from bitrot.
-
-Support for ELF is being worked on. It should be available in version 2.2.
+run gcc on it. Or run "gcc -xassembler-with-cpp foo.s".
-This version does not support the IBM RS/6000. I am not aware of any work
-being done to support it. If you are interested in working on it, please
-contact me.
+Support for ELF should work now for sparc, hppa, i386, alpha, m68k,
+MIPS, powerpc.
-This version does not support the HP PA/RISC running HP/UX. A modified version
-of gas 1.36 which does (well enough for gcc) is available by ftp from
-jaguar.cs.utah.edu.
+Support for sequent (ns32k), tahoe, i860, m88k may be suffering from bitrot.
If you try out gas on some host or target not listed above, please let me know
the results, so I can update the list.
Compiler Support Hacks
======================
-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.
+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-gnu-utils@prep.ai.mit.edu. They may be
-cross-posted to bug-gcc if they affect the use of gas with gcc. They should
-not be reported just to bug-gcc, since I don't read that list, and therefore
-wouldn't see them.
+Bugs in gas should be reported to bug-gnu-utils@gnu.org. They may be
+cross-posted to bug-gcc if they affect the use of gas with gcc. They
+should not be reported just to bug-gcc, since I don't read that list,
+and therefore wouldn't see them.
If you report a bug in GAS, please remember to include:
1. You might be mistaken.
2. It might take us a lot of time to install things to regenerate that file.
3. We might get a different file from the one you got, and might not see any
-bug.
+ bug.
To save us these delays and uncertainties, always send the input file for the
program that failed. A smaller test case that demonstrates the problem is of
projects / deliverable / binutils-gdb.git / blobdiff