Re: Emacs core dump

[Eli Zaretskii]

On 12 Jun 2001, Cyprian Adam Laskowski wrote:

> The cores have this in common: first, they were all accompanied by either a
> "Segmentation Fault" or an "Abort"; secondly, about 1% into the core files, 
> they
> all seem to have the following:
> 
> --------------
> ^@^@Can't fstat (%s): errno %d
> ^@Can't mmap (%s): errno %d
> ^@.bss^@Can't find .bss in %s.
> ^@.bss shrank when undumping???
> ^@Can't creat (%s): errno %d
> ^@Can't ftruncate (%s): errno %d

It is normally not useful to look at the core file's contents except
through a debugger.  A core file is in a nutshell a snapshot of the
program's address space at the time of a crash.  So it is full of
binary garbage not easily understood by humans.

The first step to debug a crash given a core file is to type this at
your shell's prompt:

     gdb emacs core

(assuming the core file's name is `core').

Then, when GDB starts and prints its prompt "(gdb)" type "bt RET"
(without the quotes).  This will print the backtrace of function calls
which led to the crash.  Try to see if that backtrace is the same for
all the core files you have.