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- README for gdb-4.9 release
- Updated 10-May-93 by Fred Fish
-
- This is GDB, the GNU source-level debugger, presently running under un*x.
- A summary of new features is in the file `NEWS'.
-
-
- Unpacking and Installation -- quick overview
- ==========================
-
- In this release, the GDB debugger sources, the generic GNU include
- files, the BFD ("binary file description") library, the readline library,
- and other libraries all have directories of their own underneath
- the gdb-4.9 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 gdb-4.9.tar.z or gdb-4.9.tar.Z file, you'll find
- a directory called `gdb-4.9', which contains:
-
- Makefile.in config.sub* glob/ opcodes/
- README configure* include/ readline/
- bfd/ configure.in libiberty/ texinfo/
- config/ etc/ mmalloc/
- config.guess* gdb/ move-if-change*
-
- To build GDB, you can just do:
-
- cd gdb-4.9
- ./configure
- make
- cp gdb/gdb /usr/local/bin/gdb (or wherever you want)
-
- This will configure and build all the libraries as well as GDB.
- 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.
-
- GDB can be used as a cross-debugger, running on a machine of one type
- while debugging a program running on a machine of another type. See below.
-
-
- More Documentation
- ******************
-
- The GDB 4 release includes an already-formatted reference card,
- ready for printing with PostScript or GhostScript, in the `gdb'
- subdirectory of the main source directory. (In `gdb-4.9/gdb/refcard.ps'.)
- If you can use PostScript or GhostScript with your printer, you can
- print the reference card immediately with `refcard.ps'.
-
- The release also includes the source for the reference card. You
- can format it, using TeX, by typing:
-
- make refcard.dvi
-
- The GDB reference card is designed to print in landscape mode on US
- "letter" size paper; that is, on a sheet 11 inches wide by 8.5 inches
- high. You will need to specify this form of printing as an option to
- your DVI output program.
-
- All the documentation for GDB comes as part of the machine-readable
- distribution. The documentation is written in Texinfo format, which is
- a documentation system that uses a single source file to produce both
- on-line information and a printed manual. You can use one of the Info
- formatting commands to create the on-line version of the documentation
- and TeX (or `texi2roff') to typeset the printed version.
-
- GDB includes an already formatted copy of the on-line Info version of
- this manual in the `gdb' subdirectory. The main Info file is
- `gdb-VERSION-NUMBER/gdb/gdb.info', and it refers to subordinate files
- matching `gdb.info*' in the same directory. If necessary, you can
- print out these files, or read them with any editor; but they are
- easier to read using the `info' subsystem in GNU Emacs or the
- standalone `info' program, available as part of the GNU Texinfo
- distribution.
-
- If you want to format these Info files yourself, you need one of the
- Info formatting programs, such as `texinfo-format-buffer' or `makeinfo'.
-
- If you have `makeinfo' installed, and are in the top level GDB
- source directory (`gdb-4.9', in the case of version 4.9), you can make
- the Info file by typing:
-
- cd gdb
- make gdb.info
-
- If you want to typeset and print copies of this manual, you need TeX,
- a program to print its DVI output files, and `texinfo.tex', the Texinfo
- definitions file.
-
- TeX is a typesetting program; it does not print files directly, but
- produces output files called DVI files. To print a typeset document,
- you need a program to print DVI files. If your system has TeX
- installed, chances are it has such a program. The precise command to
- use depends on your system; `lpr -d' is common; another (for PostScript
- devices) is `dvips'. The DVI print command may require a file name
- without any extension or a `.dvi' extension.
-
- TeX also requires a macro definitions file called `texinfo.tex'.
- This file tells TeX how to typeset a document written in Texinfo
- format. On its own, TeX cannot read, much less typeset a Texinfo file.
- `texinfo.tex' is distributed with GDB and is located in the
- `gdb-VERSION-NUMBER/texinfo' directory.
-
- If you have TeX and a DVI printer program installed, you can typeset
- and print this manual. First switch to the the `gdb' subdirectory of
- the main source directory (for example, to `gdb-4.9/gdb') and then type:
-
- make gdb.dvi
-
-
- Installing GDB
- **************
-
- GDB comes with a `configure' script that automates the process of
- preparing GDB for installation; you can then use `make' to build the
- `gdb' program.
-
- The GDB distribution includes all the source code you need for GDB in
- a single directory, whose name is usually composed by appending the
- version number to `gdb'.
-
- For example, the GDB version 4.9 distribution is in the `gdb-4.9'
- directory. That directory contains:
-
- `gdb-4.9/configure (and supporting files)'
- script for configuring GDB and all its supporting libraries.
-
- `gdb-4.9/gdb'
- the source specific to GDB itself
-
- `gdb-4.9/bfd'
- source for the Binary File Descriptor library
-
- `gdb-4.9/include'
- GNU include files
-
- `gdb-4.9/libiberty'
- source for the `-liberty' free software library
-
- `gdb-4.9/opcodes'
- source for the library of opcode tables and disassemblers
-
- `gdb-4.9/readline'
- source for the GNU command-line interface
-
- `gdb-4.9/glob'
- source for the GNU filename pattern-matching subroutine
-
- `gdb-4.9/mmalloc'
- source for the GNU memory-mapped malloc package
-
- 'gdb-4.9/sim'
- source for some simulators (z8000, H8/300, H8/500, etc)
-
- The simplest way to configure and build GDB is to run `configure'
- from the `gdb-VERSION-NUMBER' source directory, which in this example
- is the `gdb-4.9' directory.
-
- First switch to the `gdb-VERSION-NUMBER' source directory if you are
- not already in it; then run `configure'. Pass the identifier for the
- platform on which GDB will run as an argument.
-
- For example:
-
- cd gdb-4.9
- ./configure HOST
- make
-
- where HOST is an identifier such as `sun4' or `decstation', that
- identifies the platform where GDB will run.
-
- Running `configure HOST' followed by `make' builds the `bfd',
- `readline', `mmalloc', and `libiberty' libraries, then `gdb' itself.
- The configured source files, and the binaries, are left in the
- corresponding source directories.
-
- `configure' 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 `gdb-4.9'
- source directory for version 4.9, `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 GDB distribution, if you only want to configure that
- subdirectory; but be sure to specify a path to it.
-
- For example, with version 4.9, type the following to configure only
- the `bfd' subdirectory:
-
- cd gdb-4.9/bfd
- ../configure HOST
-
- You can install `gdb' anywhere; it has no hardwired paths. However,
- you should make sure that the shell on your path (named by the `SHELL'
- environment variable) is publicly readable. Remember that GDB uses the
- shell to start your program--some systems refuse to let GDB debug child
- processes whose programs are not readable.
-
-
- Compiling GDB in another directory
- ==================================
-
- If you want to run GDB versions for several host or target machines,
- you need a different `gdb' 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 correctly (GNU `make' and SunOS 'make' are two that should),
- running `make' in each of these directories builds the `gdb' program
- specified there.
-
- To build `gdb' 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 4.9, you can build GDB in a separate
- directory for a Sun 4 like this:
-
- cd gdb-4.9
- mkdir ../gdb-sun4
- cd ../gdb-sun4
- ../gdb-4.9/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 `gdb-sun4/libiberty', and GDB itself in `gdb-sun4/gdb'.
-
- One popular reason to build several GDB configurations in separate
- directories is to configure GDB for cross-compiling (where GDB 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 `gdb-4.9' (or in a separate configured directory configured with
- `--srcdir=PATH/gdb-4.9'), you will build all the required libraries,
- and then build GDB.
-
- 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
- ======================================
-
- 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 GDB 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 sun4
- sparc-sun-sunos411
- % sh config.sub sun3
- m68k-sun-sunos411
- % sh config.sub decstation
- mips-dec-ultrix42
- % sh config.sub hp300bsd
- m68k-hp-bsd
- % sh config.sub i386v
- i386-unknown-sysv
- % sh config.sub i786v
- Invalid configuration `i786v': machine `i786v' not recognized
-
- `config.sub' is also distributed in the GDB source directory
- (`gdb-4.9', for version 4.9).
-
-
- `configure' options
- ===================
-
- Here is a summary of the `configure' options and arguments that are
- most often useful for building GDB. `configure' also has several other
- options not listed here. *note : (configure.info)What Configure Does,
- for a full explanation of `configure'.
-
- configure [--help]
- [--prefix=DIR]
- [--srcdir=PATH]
- [--norecursion] [--rm]
- [--target=TARGET] HOST
-
- 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'.
-
- `-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 compatibly implements the `VPATH' feature.*
- Use this option to make configurations in directories separate
- from the GDB 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.
-
- `--target=TARGET'
- Configure GDB for cross-debugging programs running on the specified
- TARGET. Without this option, GDB is configured to debug programs
- that run on the same machine (HOST) as GDB itself.
-
- There is no convenient way to generate a list of all available
- targets.
-
- `HOST ...'
- Configure GDB to run on the specified HOST.
-
- There is no convenient way to generate a list of all available
- hosts.
-
- `configure' accepts other options, for compatibility with configuring
- other GNU tools recursively; but these are the only options that affect
- GDB or its supporting libraries.
-
-
- Languages other than C
- =======================
-
- GDB provides some support for debugging C++ progams. Partial Modula-2
- and Chill support is now in GDB. GDB should work with FORTRAN programs.
- (If you have problems, please send a bug report; you may have to refer to
- some FORTRAN variables with a trailing underscore). Pascal programs which
- use sets, subranges, file variables, or nested functions will not
- currently work.
-
-
- Kernel debugging
- =================
-
- I have't done this myself so I can't really offer any advice.
- Remote debugging over serial lines works fine, but the kernel debugging
- code in here has not been tested in years. Van Jacobson has
- better kernel debugging, but the UC lawyers won't let FSF have it.
-
-
- Remote debugging
- =================
-
- The files m68k-stub.c, i386-stub.c, and sparc-stub.c are examples of
- remote stubs to be used with remote.c. They are designed to run
- standalone on an m68k, i386, or SPARC cpu and communicate properly with
- the remote.c stub over a serial line.
-
- The file rem-multi.shar contains a general stub that can probably
- run on various different flavors of unix to allow debugging over a
- serial line from one machine to another.
-
- Some working remote interfaces for talking to existing ROM monitors
- are:
- remote-adapt.c AMD 29000 "Adapt"
- remote-eb.c AMD 29000 "EBMON"
- remote-es1800.c Ericsson 1800 monitor
- remote-hms.c Hitachi Micro Systems H8/300 monitor
- remote-mips.c MIPS remote debugging protocol
- remote-mm.c AMD 29000 "minimon"
- remote-nindy.c Intel 960 "Nindy"
- remote-sim.c Generalized simulator protocol
- remote-st2000.c Tandem ST-2000 monitor
- remote-udi.c AMD 29000 using the AMD "Universal Debug Interface"
- remote-vx.c VxWorks realtime kernel
- remote-z8k.c Zilog Z8000 simulator
-
- Remote-vx.c and the vx-share subdirectory contain a remote interface for the
- VxWorks realtime kernel, which communicates over TCP using the Sun
- RPC library. This would be a useful starting point for other remote-
- via-ethernet back ends.
-
- Remote-udi.c and the 29k-share subdirectory contain a remote interface
- for AMD 29000 programs, which uses the AMD "Universal Debug Interface".
- This allows GDB to talk to software simulators, emulators, and/or bare
- hardware boards, via network or serial interfaces. Note that GDB only
- provides an interface that speaks UDI, not a complete solution. You
- will need something on the other end that also speaks UDI.
-
-
- Reporting Bugs
- ===============
-
- The correct address for reporting bugs found in gdb is
- "bug-gdb@prep.ai.mit.edu". Please email all bugs to that address.
- Please include the GDB version number (e.g. gdb-4.9), and how
- you configured it (e.g. "sun4" or "mach386 host, i586-intel-synopsys
- target").
-
- Known bugs:
-
- * Under Ultrix 4.2 (DECstation-3100), we have seen problems with backtraces
- after interrupting the inferior out of a read(). The problem is caused by
- ptrace() returning an incorrect value for register 30. As far as we can
- tell, this is a kernel problem. Any help with this would be greatly
- appreciated.
-
- * On the SPARC GDB reports incorrect values of struct arguments to
- functions, for the seventh and subsequent arguments. We have been looking
- at this but no fix is available yet.
-
- * On DECstations there are warnings about shift counts out of range in
- various BFD modules. None of them is a cause for alarm, they are actually
- a result of bugs in the DECstation compiler.
-
- * On Solaris using the "run" command when the program is already running
- restarts the program, but may leave a core dump from the previous
- execution in the current directory. Other SVR4 based systems don't seem
- to have this problem, using the same gdb source code.
-
- GDB can produce warnings about symbols that it does not understand. By
- default, these warnings are disabled. You can enable them by executing
- `set complaint 10' (which you can put in your ~/.gdbinit if you like).
- I recommend doing this if you are working on a compiler, assembler,
- linker, or gdb, since it will point out problems that you may be able
- to fix. Warnings produced during symbol reading indicate some mismatch
- between the object file and GDB's symbol reading code. In many cases,
- it's a mismatch between the specs for the object file format, and what
- the compiler actually outputs or the debugger actually understands.
-
-
- X Windows versus GDB
- =====================
-
- There is an "xxgdb", which seems to work for simple operations,
- which was posted to comp.sources.x.
-
- For those interested in auto display of source and the availability of
- an editor while debugging I suggest trying gdb-mode in gnu-emacs
- (Try typing M-x gdb RETURN). Comments on this mode are welcome.
-
-
- Writing Code for GDB
- =====================
-
- There is a lot of information about writing code for GDB in the
- internals manual, distributed with GDB in gdb/doc/gdbint.texinfo. You
- can read it by hand, print it by using TeX and texinfo, or process it
- into an `info' file for use with Emacs' info mode or the standalone
- `info' program. In particular, see the nodes Getting Started,
- Debugging GDB, New Architectures, Coding Style, Clean Design, and
- Submitting Patches.
-
- If you are pondering writing anything but a short patch, especially
- take note of the information about copyrights in the node Submitting
- Patches. It can take quite a while to get all the paperwork done, so
- we encourage you to start that process as soon as you decide you are
- planning to work on something, or at least well ahead of when you
- think you will be ready to submit the patches.
-
-
- GDB Testsuite
- =============
-
- There is a dejagnu based testsuite available for testing your newly
- built gdb, or for regression testing gdb's with local modifications.
- The testsuite is distributed separately from the base gdb distribution
- for the convenience of people that wish to get either gdb or the testsuite
- separately.
-
- The name of the testsuite is gdb-4.9-testsuite.tar.z. You unpack it in the
- same directory in which you unpacked the base gdb distribution, and it
- will create and populate the directory gdb-4.9/gdb/testsuite.
-
- Running the testsuite requires the prior installation of dejagnu, which
- should be available via ftp. Once dejagnu is installed, you can run
- the tests in one of two ways:
-
- (1) cd gdb-4.9/gdb (assuming you also unpacked gdb)
- make check
-
- or
-
- (2) cd gdb-4.9/gdb/testsuite
- make (builds the test executables)
- make site.exp (builds the site specific file)
- runtest -tool gdb GDB=../gdb (or GDB=<somepath> as appropriate)
-
- The second method gives you slightly more control in case of problems with
- building one or more test executables, in case you wish to remove some
- test executables before running the tests, or if you are using the testsuite
- 'standalone', without it being part of the gdb source tree.
-
- See the dejagnu documentation for further details.
-
-
- (this is for editing this file with GNU emacs)
- Local Variables:
- mode: text
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-