diff options
Diffstat (limited to 'gdb/README')
| -rw-r--r-- | gdb/README | 618 |
1 files changed, 618 insertions, 0 deletions
diff --git a/gdb/README b/gdb/README new file mode 100644 index 00000000000..fd791ced523 --- /dev/null +++ b/gdb/README @@ -0,0 +1,618 @@ + README for gdb-4.18 release + Updated 4 Apr 1999 by Jim Blandy + +This is GDB, the GNU source-level debugger. +A summary of new features is in the file `NEWS'. + +See the GDB home page at http://www.cygnus.com/gdb/ for up to date +release information, mailing list links and archives, etc. + + +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-4.18 directory. The idea is that a variety of GNU +tools can share a common copy of these things. Be aware of variation +over time--for example don't try to build gdb with a copy of bfd from +a release other than the gdb release (such as a binutils or gas +release), especially if the releases are more than a few weeks apart. +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-4.18.tar.gz file, you'll find a directory +called `gdb-4.18', which contains: + + COPYING config.sub* libiberty/ opcodes/ + COPYING.LIB configure* mmalloc/ readline/ + Makefile.in configure.in move-if-change* sim/ + README etc/ mpw-README texinfo/ + bfd/ gdb/ mpw-build.in utils/ + config/ include/ mpw-config.in + config.guess* install.sh* mpw-configure + +To build GDB, you can just do: + + cd gdb-4.18 + ./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 requires an ANSI C compiler. If you do not have an ANSI C +compiler for your system, you may be able to download and install the +GNU CC compiler. It is available via anonymous FTP from ftp.gnu.org, +in /pub/gnu/gcc (as a URL, that's ftp://ftp.gnu.org/pub/gnu/gcc). + +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 +****************** + + 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/doc' subdirectory. The main Info file is +`gdb-4.18/gdb/doc/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-4.18', in the case of version 4.18), you can make +the Info file by typing: + + cd gdb/doc + make 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. This file is included in the GDB +distribution, in the directory `gdb-4.18/texinfo'. + + 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-4.18/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-4.18/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 4.18 distribution is in the `gdb-4.18' +directory. That directory contains: + +`gdb-4.18/{COPYING,COPYING.LIB}' + Standard GNU license files. Please read them. + +`gdb-4.18/bfd' + source for the Binary File Descriptor library + +`gdb-4.18/config*' + script for configuring GDB, along with other support files + +`gdb-4.18/gdb' + the source specific to GDB itself + +`gdb-4.18/include' + GNU include files + +`gdb-4.18/libiberty' + source for the `-liberty' free software library + +`gdb-4.18/mmalloc' + source for the GNU memory-mapped malloc package + +`gdb-4.18/opcodes' + source for the library of opcode tables and disassemblers + +`gdb-4.18/readline' + source for the GNU command-line interface + +`gdb-4.18/sim' + source for some simulators (ARM, D10V, SPARC, M32R, MIPS, PPC, V850, etc) + +`gdb-4.18/intl' + source for the GNU gettext library, for internationalization. + This is slightly modified from the standalone gettext + distribution you can get from GNU. + +`gdb-4.18/texinfo' + The `texinfo.tex' file, which you need in order to make a printed + manual using TeX. + +`gdb-4.18/etc' + Coding standards, useful files for editing GDB, and other + miscellanea. + +`gdb-4.18/utils' + A grab bag of random utilities. + + + 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-4.18' directory. + + First switch to the `gdb-VERSION-NUMBER' source directory if you are +not already in it; then run `configure'. + + For example: + + cd gdb-4.18 + ./configure + make + + Running `configure' 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 + + If you run `configure' from a directory that contains source +directories for multiple libraries or programs, such as the `gdb-4.18' +source directory for version 4.18, `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 4.18, type the following to configure only +the `bfd' subdirectory: + + cd gdb-4.18/bfd + ../configure + + 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 4.18, you can build GDB in a separate +directory for a Sun 4 like this: + + cd gdb-4.18 + mkdir ../gdb-sun4 + cd ../gdb-sun4 + ../gdb-4.18/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-4.18' (or in a separate configured directory configured with +`--srcdir=PATH/gdb-4.18'), 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-sunos4.1.1 + % sh config.sub sun3 + m68k-sun-sunos4.1.1 + % sh config.sub decstation + mips-dec-ultrix4.2 + % sh config.sub hp300bsd + m68k-hp-bsd + % sh config.sub i386v + i386-pc-sysv + % sh config.sub i786v + Invalid configuration `i786v': machine `i786v' not recognized + +`config.sub' is also distributed in the GDB source directory +(`gdb-4.18', for version 4.18). + + +`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] + [--enable-build-warnings] + [--target=TARGET] + [--host=HOST] + [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. + +`--enable-build-warnings' + When building the GDB sources, ask the compiler to warn about any + code which looks even vaguely suspicious. You should only using + this feature if you're compiling with GNU CC. It passes the + following flags: + -Wall + -Wpointer-arith + -Wstrict-prototypes + -Wmissing-prototypes + -Wmissing-declarations + +`--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=HOST' + Configure GDB to run on the specified HOST. + + There is no convenient way to generate a list of all available + hosts. + +`HOST ...' + Same as `--host=HOST'. If you omit this, GDB will guess; it's + quite accurate. + +`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 +======================= + +See the GDB manual (gdb/doc/gdb.texinfo) for information on this. + + +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 directory gdb/gdbserver/ contains `gdbserver', a program that +allows remote debugging for Unix applications. gdbserver is only +supported for some native configurations, including Sun 3, Sun 4, +and Linux. + +There are a number of remote interfaces for talking to existing ROM +monitors and other hardware: + + remote-adapt.c AMD 29000 "Adapt" + remote-array.c Array Tech RAID controller + remote-bug.c Motorola BUG monitor + remote-d10v.c GDB protocol, talking to a d10v chip + remote-e7000.c Hitachi E7000 ICE + remote-eb.c AMD 29000 "EBMON" + remote-es.c Ericsson 1800 monitor + remote-est.c EST emulator + 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-nrom.c NetROM ROM emulator + remote-os9k.c PC running OS/9000 + remote-rdi.c ARM with Angel monitor + remote-rdp.c ARM with Demon monitor + remote-sds.c PowerPC SDS monitor + remote-sim.c Generalized simulator protocol + remote-st.c Tandem ST-2000 monitor + remote-udi.c AMD 29000 using the AMD "Universal Debug Interface" + remote-vx.c VxWorks realtime kernel + +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@gnu.org". Please email all bugs, and all requests for +help with GDB, to that address. Please include the GDB version number +(e.g., gdb-4.18), and how you configured it (e.g., "sun4" or "mach386 +host, i586-intel-synopsys target"). Since GDB now supports so many +different configurations, it is important that you be precise about this. +If at all possible, you should include the actual banner that GDB prints +when it starts up, or failing that, the actual configure command that +you used when configuring GDB. + +For more information on how/whether to report bugs, see the GDB Bugs +section of the GDB manual (gdb/doc/gdb.texinfo). + +Known bugs: + + * Under Ultrix 4.2 (DECstation-3100) or Alphas under OSF/1, 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 the frame pointer register (register 15 or + 30). As far as we can tell, this is a kernel problem. Any help + with this would be greatly appreciated. + + * Under Ultrix 4.4 (DECstation-3100), setting the TERMCAP environment + variable to a string without a trailing ':' can cause GDB to dump + core upon startup. Although the core file makes it look as though + GDB code failed, the crash actually occurs within a call to the + termcap library function tgetent(). The problem can be solved by + using the GNU Termcap library. + + Alphas running OSF/1 (versions 1.0 through 2.1) have the same buggy + termcap code, but GDB behaves strangely rather than crashing. + + * 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. + + * Notes for the DEC Alpha using OSF/1: + The debugging output of native cc has two known problems; we view these + as compiler bugs. + The linker miscompacts symbol tables, which causes gdb to confuse the + type of variables or results in `struct <illegal>' type outputs. + dbx has the same problems with those executables. A workaround is to + specify -Wl,-b when linking, but that will increase the executable size + considerably. + If a structure has incomplete type in one file (e.g., "struct foo *" + without a definition for "struct foo"), gdb will be unable to find the + structure definition from another file. + It has been reported that the Ultrix 4.3A compiler on decstations has the + same problems. + + * Notes for Solaris 2.x, using the SPARCworks cc compiler: + You have to compile your program with the -xs option of the SPARCworks + compiler to be able to debug your program with gdb. + Under Solaris 2.3 you also need patch 101409-03 (Jumbo linker patch). + Under Solaris 2.2, if you have patch 101052 installed, make sure + that it is at least at revision 101052-06. + + * Under Irix 5 for SGIs, you must have installed the `compiler_dev.hdr' + subsystem that is on the IDO CD, otherwise you will get complaints + that certain files such as `/usr/include/syms.h' cannot be found. + + * Notes for BSD/386: + To compile gdb-4.18 on BSD/386, you must run the configure script and + its subscripts with bash. Here is an easy way to do this: + + bash -c 'CONFIG_SHELL=/bin/bash ./configure' + + (configure will report i386-unknown-bsd). Then, compile with the + standard "make" command. + +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 +===================== + +You should check out DDD, the Data Display Debugger. Here's the blurb +from the DDD web site, http://www.cs.tu-bs.de/softech/ddd: + + The Data Display Debugger (DDD) is a popular graphical user + interface for command-line debuggers such as GDB, DBX, JDB, WDB, + XDB, the Perl debugger, and the Python debugger. Besides ``usual'' + front-end features such as viewing source texts, DDD has become + famous through its interactive graphical data display, where data + structures are displayed as graphs. A simple mouse click + dereferences pointers or views structure contents, updated each + time the program stops. Using DDD, you can reason about your + application by watching its data, not just by viewing it execute + lines of source code. + +Emacs users will very likely enjoy the Grand Unified Debugger mode; +try typing `M-x gdb RET'. + +Those interested in experimenting with a new kind of gdb-mode +should load gdb/gdba.el into GNU Emacs 19.25 or later. Comments +on this mode are also 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. + +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 GDBs with local modifications. + +Running the testsuite requires the prior installation of DejaGNU, +which is generally available via ftp; you'll need a pretty recent +release. Once DejaGNU is installed, you can run the tests in one of +two ways: + + (1) cd gdb-4.18/gdb (assuming you also unpacked gdb) + make check + +or + + (2) cd gdb-4.18/gdb/testsuite + 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 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 +End: |