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+This is GDB, the GNU source-level debugger, presently running under un*x.
+Before compiling GDB, you must tell GDB what kind of machine you are
+running on. To do this, type `config.gdb machine', where machine is
+something like `vax' or `sun2'. For a list of valid machine types,
+type `config.gdb'.
+Normally config.gdb edits the makefile as necessary. If you have to
+edit the makefile on a standard machine listed in config.gdb this
+should be considered a bug and reported as such.
+Once these files are set up, just `make' will do everything,
+producing an executable `gdb' in this directory.
+If you want a new (current to this release) version of the manual, you
+will have to use the gdb.texinfo file provided with this distribution.
+The gdb.texinfo file requires the texinfo-format-buffer command from
+emacs 18.55 or later.
+About languages other than C...
+C++ support has been integrated into gdb. GDB should work with
+FORTRAN programs (if you have problem, please send a bug report), but
+I am not aware of anyone who is working on getting it to use the
+syntax of any language other than C or C++. Pascal programs which use
+sets, subranges, file variables, or nested functions will not
+currently work.
+About -gg format...
+Currently GDB version 3.x does *not* support GCC's -gg format. This
+is because it (in theory) has fast enough startup on dbx debugging
+format object files that -gg format is unnecessary (and hence
+undesirable, since it wastes space and processing power in gcc). I
+would like to hear people's opinions on the amount of time currently
+spent in startup; is it fast enough?
+About remote debugging...
+The two files remote-multi.shar and remote-sa.m68k.shar contain two
+examples of a remote stub to be used with remote.c. The the -multi
+file is a general stub that can probably be running on various
+different flavors of unix to allow debugging over a serial line from
+one machine to another. The remote-sa.m68k.shar is designed to run
+standalone on a 68k type cpu and communicate properley with the
+remote.c stub over a serial line.
+About reporting bugs...
+The correct address for reporting bugs found with gdb is
+"bug-gdb@prep.ai.mit.edu". Please send all bugs to that address.
+About xgdb...
+xgdb.c was provided to us by the user community; it is not an integral
+part of the gdb distribution. The problem of providing visual
+debugging support on top of gdb is peripheral to the GNU project and
+(at least right now) we can't afford to put time into it. So while we
+will be happy to incorporate user fixes to xgdb.c, we do not guarantee
+that it will work and we will not fix bugs reported in it. Someone is
+working on writing a new XGDB, so improving (e.g. by fixing it so that
+it will work, if it doesn't currently) the current one is not worth it.
+For those intersted in auto display of source and the availability of
+an editor while debugging I suggest trying gdb-mode in gnu-emacs.
+Comments on this mode are welcome.
+About the machine-dependent files...
+m-<machine>.h (param.h is a link to this file).
+This file contains macro definitions that express information
+about the machine's registers, stack frame format and instructions.
+<machine>-opcode.h (opcode.h is a link to this file).
+<machine>-pinsn.c (pinsn.c is a link to this file).
+These files contain the information necessary to print instructions
+for your cpu type.
+<machine>-dep.c (dep.c is a link to this file).
+Those routines which provide a low level interface to ptrace and which
+tend to be machine-dependent. (The machine-independent routines are in
+`infrun.c' and `inflow.c')
+About writing code for GDB...
+We appreciate having users contribute code that is of general use, but
+for it to be included in future GDB releases it must be cleanly
+written. We do not want to include changes that will needlessly make future
+maintainance difficult. It is not much harder to do things right, and
+in the long term it is worth it to the GNU project, and probably to
+you individually as well.
+Please code according to the GNU coding standards. If you do not have
+a copy, you can request one by sending mail to gnu@prep.ai.mit.edu.
+Please try to avoid making machine-specific changes to
+machine-independent files (i.e. all files except "param.h" and
+"dep.c". "pinsn.c" and "opcode.h" are processor-specific but not
+operating system-dependent). If this is unavoidable, put a hook in
+the machine-independent file which calls a (possibly)
+machine-dependent macro (for example, the IGNORE_SYMBOL macro can be
+used for any symbols which need to be ignored on a specific machine.
+Calling IGNORE_SYMBOL in dbxread.c is a lot cleaner than a maze of #if
+defined's). The machine-independent code should do whatever "most"
+machines want if the macro is not defined in param.h. Using #if
+defined can sometimes be OK (e.g. SET_STACK_LIMIT_HUGE) but should be
+conditionalized on a specific feature of an operating system (set in
+param.h) rather than something like #if defined(vax) or #if
+It is better to replace entire routines which may be system-specific,
+rather than put in a whole bunch of hooks which are probably not going
+to be helpful for any purpose other than your changes. For example,
+if you want to modify dbxread.c to deal with DBX debugging symbols
+which are in COFF files rather than BSD a.out files, do something
+along the lines of a macro GET_NEXT_SYMBOL, which could have
+different definitions for COFF and a.out, rather than trying to put
+the necessary changes throughout all the code in dbxread.c that
+currently assumes BSD format.
+Please avoid duplicating code. For example, if something needs to be
+changed in read_inferior_memory, it is very painful because there is a
+copy in every dep.c file. The correct way to do this is to put (in
+this case) the standard ptrace interfaces in a separate file ptrace.c,
+which is used by all systems which have ptrace. ptrace.c would deal
+with variations between systems the same way any system-independent
+file would (hooks, #if defined, etc.).
+About debugging gdb with itself...
+You probably want to do a "make TAGS" after you configure your
+distribution; this will put the machine dependent routines for your
+local machine where they will be accessed first by a M-period .
+Also, make sure that you've compiled gdb with your local cc or taken
+appropriate precautions regarding ansification of include files. See
+the Makefile for more information.
+The "info" command, when executed without a subcommand in a gdb being
+debugged by gdb, will pop you back up to the top level gdb. See
+.gdbinit for more details.