- GDB 4.0 -- what has changed since 3.5?
+ What has changed since GDB-3.5?
+ (Organized release by release)
+
+*** Changes in GDB-4.6:
+
+ * Better support for C++ function names
+
+GDB now accepts as input the "demangled form" of C++ overloaded function
+names and member function names, and can do command completion on such names
+(using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
+single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
+Make use of command completion, it is your friend.
+
+GDB also now accepts a variety of C++ mangled symbol formats. They are
+the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
+You can tell GDB which format to use by doing a 'set demangle-style {gnu,
+lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
+for the list of formats.
+
+ * G++ symbol mangling problem
+
+Recent versions of gcc have a bug in how they emit debugging information for
+C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
+directory) can be applied to gcc to fix the problem. Alternatively, if you
+can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
+usual symptom is difficulty with setting breakpoints on methods. GDB complains
+about the method being non-existent. (We believe that version 2.2.2 of GCC has
+this problem.)
+
+ * New 'maintenance' command
+
+All of the commands related to hacking GDB internals have been moved out of
+the main command set, and now live behind the 'maintenance' command. This
+can also be abbreviated as 'mt'. The following changes were made:
+
+ dump-me -> maintenance dump-me
+ info all-breakpoints -> maintenance info breakpoints
+ printmsyms -> maintenance print msyms
+ printobjfiles -> maintenance print objfiles
+ printpsyms -> maintenance print psymbols
+ printsyms -> maintenance print symbols
+
+The following commands are new:
+
+ maintenance demangle Call internal GDB demangler routine to
+ demangle a C++ link name and prints the result.
+ maintenance print type Print a type chain for a given symbol
+
+ * Change to .gdbinit file processing
+
+We now read the $HOME/.gdbinit file before processing the argv arguments
+(e.g. reading symbol files or core files). This allows global parameters to
+be set, which will apply during the symbol reading. The ./.gdbinit is still
+read after argv processing.
+
+ * New hosts supported
+
+Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
+
+Linux support i386-unknown-linux or linux
+
+We are also including code to support the HP/PA running BSD and HPUX. This
+is almost guaranteed not to work, as we didn't have time to test or build it
+for this release. We are including it so that the more adventurous (or
+masochistic) of you can play with it. We also had major problems with the
+fact that the compiler that we got from HP doesn't support the -g option.
+It costs extra.
+
+ * New targets supported
+
+Hitachi H8/300 h8300-hitachi-hms or h8300hms
+
+ * More smarts about finding #include files
+
+GDB now remembers the compilation directory for all include files, and for
+all files from which C is generated (like yacc and lex sources). This
+greatly improves GDB's ability to find yacc/lex sources, and include files,
+especially if you are debugging your program from a directory different from
+the one that contains your sources.
+
+We also fixed a bug which caused difficulty with listing and setting
+breakpoints in include files which contain C code. (In the past, you had to
+try twice in order to list an include file that you hadn't looked at before.)
+
+ * Interesting infernals change
+
+GDB now deals with arbitrary numbers of sections, where the symbols for each
+section must be relocated relative to that section's landing place in the
+target's address space. This work was needed to support ELF with embedded
+stabs used by Solaris-2.0.
+
+ * Bug fixes (of course!)
+
+There have been loads of fixes for the following things:
+ mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
+ i960, stabs, DOS(GO32), procfs, etc...
+
+See the ChangeLog for details.
+
+*** Changes in GDB-4.5:
+
+ * New machines supported (host and target)
+
+IBM RS6000 running AIX rs6000-ibm-aix or rs6000
+
+SGI Irix-4.x mips-sgi-irix4 or iris4
+
+ * New malloc package
+
+GDB now uses a new memory manager called mmalloc, based on gmalloc.
+Mmalloc is capable of handling mutiple heaps of memory. It is also
+capable of saving a heap to a file, and then mapping it back in later.
+This can be used to greatly speedup the startup of GDB by using a
+pre-parsed symbol table which lives in a mmalloc managed heap. For
+more details, please read mmalloc/mmalloc.texi.
+
+ * info proc
+
+The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
+'help info proc' for details.
+
+ * MIPS ecoff symbol table format
+
+The code that reads MIPS symbol table format is now supported on all hosts.
+Thanks to MIPS for releasing the sym.h and symconst.h files to make this
+possible.
+
+ * File name changes for MS-DOS
+
+Many files in the config directories have been renamed to make it easier to
+support GDB on MS-DOSe systems (which have very restrictive file name
+conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
+environment) is close to working but has some remaining problems. Note
+that debugging of DOS programs is not supported, due to limitations
+in the ``operating system'', but it can be used to host cross-debugging.
+
+ * Cross byte order fixes
+
+Many fixes have been made to support cross debugging of Sparc and MIPS
+targets from hosts whose byte order differs.
+
+ * New -mapped and -readnow options
+
+If memory-mapped files are available on your system through the 'mmap'
+system call, you can use the -mapped option on the `file' or
+`symbol-file' commands to cause GDB to write the symbols from your
+program into a reusable file. If the program you are debugging is
+called `/path/fred', the mapped symbol file will be `./fred.syms'.
+Future GDB debugging sessions will notice the presence of this file,
+and will quickly map in symbol information from it, rather than reading
+the symbol table from the executable program. Using the '-mapped'
+option in a GDB `file' or `symbol-file' command has the same effect as
+starting GDB with the '-mapped' command-line option.
+
+You can cause GDB to read the entire symbol table immediately by using
+the '-readnow' option with any of the commands that load symbol table
+information (or on the GDB command line). This makes the command
+slower, but makes future operations faster.
+
+The -mapped and -readnow options are typically combined in order to
+build a `fred.syms' file that contains complete symbol information.
+A simple GDB invocation to do nothing but build a `.syms' file for future
+use is:
+
+ gdb -batch -nx -mapped -readnow programname
+
+The `.syms' file is specific to the host machine on which GDB is run.
+It holds an exact image of GDB's internal symbol table. It cannot be
+shared across multiple host platforms.
+
+ * longjmp() handling
+
+GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
+siglongjmp() without losing control. This feature has not yet been ported to
+all systems. It currently works on many 386 platforms, all MIPS-based
+platforms (SGI, DECstation, etc), and Sun3/4.
+
+ * Solaris 2.0
+
+Preliminary work has been put in to support the new Solaris OS from Sun. At
+this time, it can control and debug processes, but it is not capable of
+reading symbols.
+
+ * Bug fixes
+
+As always, many many bug fixes. The major areas were with g++, and mipsread.
+People using the MIPS-based platforms should experience fewer mysterious
+crashes and trashed symbol tables.
+
+*** Changes in GDB-4.4:
+
+ * New machines supported (host and target)
+
+SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
+ (except core files)
+BSD Reno on Vax vax-dec-bsd
+Ultrix on Vax vax-dec-ultrix
+
+ * New machines supported (target)
+
+AMD 29000 embedded, using EBMON a29k-none-none
+
+ * C++ support
+
+GDB continues to improve its handling of C++. `References' work better.
+The demangler has also been improved, and now deals with symbols mangled as
+per the Annotated C++ Reference Guide.
+
+GDB also now handles `stabs' symbol information embedded in MIPS
+`ecoff' symbol tables. Since the ecoff format was not easily
+extensible to handle new languages such as C++, this appeared to be a
+good way to put C++ debugging info into MIPS binaries. This option
+will be supported in the GNU C compiler, version 2, when it is
+released.
+
+ * New features for SVR4
+
+GDB now handles SVR4 shared libraries, in the same fashion as SunOS
+shared libraries. Debugging dynamically linked programs should present
+only minor differences from debugging statically linked programs.
+
+The `info proc' command will print out information about any process
+on an SVR4 system (including the one you are debugging). At the moment,
+it prints the address mappings of the process.
+
+If you bring up GDB on another SVR4 system, please send mail to
+bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
+
+ * Better dynamic linking support in SunOS
+
+Reading symbols from shared libraries which contain debugging symbols
+now works properly. However, there remain issues such as automatic
+skipping of `transfer vector' code during function calls, which
+make it harder to debug code in a shared library, than to debug the
+same code linked statically.
+
+ * New Getopt
+
+GDB is now using the latest `getopt' routines from the FSF. This
+version accepts the -- prefix for options with long names. GDB will
+continue to accept the old forms (-option and +option) as well.
+Various single letter abbreviations for options have been explicity
+added to the option table so that they won't get overshadowed in the
+future by other options that begin with the same letter.
+
+ * Bugs fixed
+
+The `cleanup_undefined_types' bug that many of you noticed has been squashed.
+Many assorted bugs have been handled. Many more remain to be handled.
+See the various ChangeLog files (primarily in gdb and bfd) for details.
+
+
+*** Changes in GDB-4.3:
+
+ * New machines supported (host and target)
+
+Amiga 3000 running Amix m68k-cbm-svr4 or amix
+NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
+Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
+
+ * Almost SCO Unix support
+
+We had hoped to support:
+SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
+(except for core file support), but we discovered very late in the release
+that it has problems with process groups that render gdb unusable. Sorry
+about that. I encourage people to fix it and post the fixes.
+
+ * Preliminary ELF and DWARF support
+
+GDB can read ELF object files on System V Release 4, and can handle
+debugging records for C, in DWARF format, in ELF files. This support
+is preliminary. If you bring up GDB on another SVR4 system, please
+send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
+reqired (if any).
+
+ * New Readline
+
+GDB now uses the latest `readline' library. One user-visible change
+is that two tabs will list possible command completions, which previously
+required typing M-? (meta-question mark, or ESC ?).
+
+ * Bugs fixed
+
+The `stepi' bug that many of you noticed has been squashed.
+Many bugs in C++ have been handled. Many more remain to be handled.
+See the various ChangeLog files (primarily in gdb and bfd) for details.
+
+ * State of the MIPS world (in case you wondered):
+
+GDB can understand the symbol tables emitted by the compilers
+supplied by most vendors of MIPS-based machines, including DEC. These
+symbol tables are in a format that essentially nobody else uses.
+
+Some versions of gcc come with an assembler post-processor called
+mips-tfile. This program is required if you want to do source-level
+debugging of gcc-compiled programs. I believe FSF does not ship
+mips-tfile with gcc version 1, but it will eventually come with gcc
+version 2.
+
+Debugging of g++ output remains a problem. g++ version 1.xx does not
+really support it at all. (If you're lucky, you should be able to get
+line numbers and stack traces to work, but no parameters or local
+variables.) With some work it should be possible to improve the
+situation somewhat.
+
+When gcc version 2 is released, you will have somewhat better luck.
+However, even then you will get confusing results for inheritance and
+methods.
+
+We will eventually provide full debugging of g++ output on
+DECstations. This will probably involve some kind of stabs-in-ecoff
+encapulation, but the details have not been worked out yet.
+
+
+*** Changes in GDB-4.2:
+
+ * Improved configuration
+
+Only one copy of `configure' exists now, and it is not self-modifying.
+Porting BFD is simpler.
+
+ * Stepping improved
+
+The `step' and `next' commands now only stop at the first instruction
+of a source line. This prevents the multiple stops that used to occur
+in switch statements, for-loops, etc. `Step' continues to stop if a
+function that has debugging information is called within the line.
+
+ * Bug fixing
+
+Lots of small bugs fixed. More remain.
+
+ * New host supported (not target)
+
+Intel 386 PC clone running Mach i386-none-mach
+
+
+*** Changes in GDB-4.1:
+
+ * Multiple source language support
+
+GDB now has internal scaffolding to handle several source languages.
+It determines the type of each source file from its filename extension,
+and will switch expression parsing and number formatting to match the
+language of the function in the currently selected stack frame.
+You can also specifically set the language to be used, with
+`set language c' or `set language modula-2'.
+
+ * GDB and Modula-2
+
+GDB now has preliminary support for the GNU Modula-2 compiler,
+currently under development at the State University of New York at
+Buffalo. Development of both GDB and the GNU Modula-2 compiler will
+continue through the fall of 1991 and into 1992.
+
+Other Modula-2 compilers are currently not supported, and attempting to
+debug programs compiled with them will likely result in an error as the
+symbol table is read. Feel free to work on it, though!
+
+There are hooks in GDB for strict type checking and range checking,
+in the `Modula-2 philosophy', but they do not currently work.
+
+ * set write on/off
+
+GDB can now write to executable and core files (e.g. patch
+a variable's value). You must turn this switch on, specify
+the file ("exec foo" or "core foo"), *then* modify it, e.g.
+by assigning a new value to a variable. Modifications take
+effect immediately.
+
+ * Automatic SunOS shared library reading
+
+When you run your program, GDB automatically determines where its
+shared libraries (if any) have been loaded, and reads their symbols.
+The `share' command is no longer needed. This also works when
+examining core files.
+
+ * set listsize
+
+You can specify the number of lines that the `list' command shows.
+The default is 10.
+
+ * New machines supported (host and target)
+
+SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
+Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
+Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
+
+ * New hosts supported (not targets)
+
+IBM RT/PC: romp-ibm-aix or rtpc
+
+ * New targets supported (not hosts)
+
+AMD 29000 embedded with COFF a29k-none-coff
+AMD 29000 embedded with a.out a29k-none-aout
+Ultracomputer remote kernel debug a29k-nyu-kern
+
+ * New remote interfaces
+
+AMD 29000 Adapt
+AMD 29000 Minimon
+
+
+*** Changes in GDB-4.0:
* New Facilities
-Gdb now paginates its output, with a ``more''-like interface. You can
-set the screen width and screen height with new ``set'' commands; they
-default to your terminal settings. Wide output is wrapped at good
-places to make the output more readable.
-
-Gdb now reads its input via the ``readline'' interface. This provides
-inline editing of commands, using familiar Emacs or VI commands (like
-``tcsh'' or the korn shell); history substitutions a la the C shell;
-and storage and recall of your command history across debugging
-sessions. The default is Emacs mode; to switch temporarily to vi mode,
-use control-meta-J or ESC control-j. You can switch permanently to vi
-mode by putting the line ``set editing-mode vi'' in the file .inputrc
-in your home directory. For full details, see the description in
-readline/inc-readline.texinfo and readline/inc-history.texinfo.
+Wide output is wrapped at good places to make the output more readable.
Gdb now supports cross-debugging from a host machine of one type to a
target machine of another type. Communication with the target system
is over serial lines. The ``target'' command handles connecting to the
remote system; the ``load'' command will download a program into the
-remote system. It also supports debugging of realtime processes
-running under VxWorks, using SunRPC Remote Procedure Calls over TCP/IP
-to talk to a debugger stub on the target system.
+remote system. Serial stubs for the m68k and i386 are provided. Gdb
+also supports debugging of realtime processes running under VxWorks,
+using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
+stub on the target system.
New CPUs supported include the AMD 29000 and Intel 960.
library, which allows a single copy of GDB to debug programs of multiple
object file types such as a.out and coff.
-There is now a GDB reference card in "gdbrc.tex".
+There is now a GDB reference card in "doc/refcard.tex". (Make targets
+refcard.dvi and refcard.ps are available to format it).
* Control-Variable user interface simplified
What follows are the NEW set commands. The command ``help set'' will
print a complete list of old and new set commands. ``help set FOO''
-will give a longer description of the variable FOO.
+will give a longer description of the variable FOO. ``show'' will show
+all of the variable descriptions and their current settings.
-caution on/off: Enables warning questions for operations that are
+confirm on/off: Enables warning questions for operations that are
hard to recover from, e.g. rerunning the program while
it is already running. Default is ON.
default is 256, or the value of the environment variable
HISTSIZE.
-history write on/off: If this value is set to ON, the history file will
+history save on/off: If this value is set to ON, the history file will
be saved after exiting gdb. If set to OFF, the
file will not be saved. The default is OFF.
to 8, 10, or 16. Note that the argument to "radix" is interpreted
in the current radix, so "set radix 10" is always a no-op.
-screen-height N: This integer value is the number of lines on a page. Default
- is 24, the current `stty rows'' setting, or the ``li#''
- setting from the termcap entry matching the environment
- variable TERM.
+height N: This integer value is the number of lines on a page. Default
+ is 24, the current `stty rows'' setting, or the ``li#''
+ setting from the termcap entry matching the environment
+ variable TERM.
-screen-width N: This integer value is the number of characters on a line.
- Default is 80, the current `stty cols'' setting, or the ``co#''
- setting from the termcap entry matching the environment
- variable TERM.
+width N: This integer value is the number of characters on a line.
+ Default is 80, the current `stty cols'' setting, or the ``co#''
+ setting from the termcap entry matching the environment
+ variable TERM.
-Note: ``set screensize'' is obsolete. Use ``set screen-height'' and
-``set screen-width'' instead.
+Note: ``set screensize'' is obsolete. Use ``set height'' and
+``set width'' instead.
-addressprint on/off: Print memory addresses in various command displays,
+print address on/off: Print memory addresses in various command displays,
such as stack traces and structure values. Gdb looks
more ``symbolic'' if you turn this off; it looks more
``machine level'' with it on. Default is ON.
-arrayprint on/off: Prettyprint arrays. New convenient format! Default
+print array on/off: Prettyprint arrays. New convenient format! Default
is OFF.
-demangle on/off: Print C++ symbols in "source" form if on, "raw" form if off.
+print demangle on/off: Print C++ symbols in "source" form if on,
+ "raw" form if off.
-asm-demangle on/off: Same, for assembler level printouts like instructions.
+print asm-demangle on/off: Same, for assembler level printouts
+ like instructions.
-vtblprint on/off: Prettyprint C++ virtual function tables. Default is OFF.
+print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
* Support for Epoch Environment.
'dir' now adds directories to the FRONT of the source search path.
The path starts off empty. Source files that contain debug information
about the directory in which they were compiled can be found even
-with an empty path; GCC includes this information. If GDB can't find
-your source file in the current directory, type "dir .".
-
- * Features removed in this release
-
-``info types'' has been removed, since it printed builtin types in a
-confusing fashion, and did not do useful things with typedefs. ``ptype''
-or ``whatis'' are more useful commands for dealing with types..
-
+with an empty path; Sun CC and GCC include this information. If GDB can't
+find your source file in the current directory, type "dir .".
* Configuring GDB for compilation
-For normal use, type ``config.gdb host''. Hosts now handled are:
-
-3b1 altos altosgas arm bigmips convex hp300bsd hp300hpux i386v i386v-g
-i386v32 i386v32-g isi littlemips m88k merlin news news1000 none np1 pn
-pyramid sun2os3 sun2os4 sun386 sun3os3 sun3os4 sun4os3 sun4os4 symmetry
-umax vax
-
-Type config.gdb +host to get a full description of each host.
-
-You can now build gdb conveniently for several architectures from the
-same sources. If config.gdb is run from a subdirectory, it configures
-the Makefile to use source files from '..'. Each subdirectory can be
-indpendently configured. An explicit source file directory can also
-be specified with the +srcdir=xxx option. Due to obscure search rules
-in the C preprocessor, if you have previously built gdb in the main
-directory, run 'make cleanconfig' in the top level directory before
-building it in a subdirectory.
+For normal use, type ``./configure host''. See README or gdb.texinfo
+for more details.
GDB now handles cross debugging. If you are remotely debugging between
-two different machines, type ``config.gdb host target''.
-Host is the machine where gdb will run; target is the machine
+two different machines, type ``./configure host -target=targ''.
+Host is the machine where GDB will run; targ is the machine
where the program that you are debugging will run.
-
-Type config.gdb +target to get a full description of each target.