Core dump analysis using gdb

I have a couple of questions regarding core dumps. I have gdb on Windows, using Cygwin.

1. What is the location of core dump file? Is it a.exe.stackdump file? (This is the only file that generated after crash) I read on other forums that the core dump file is named "core". But I don't see any file with name "core".

2. What is the command for opening and understand开发者_开发百科ing core dump file?

1. You need to configure Cygwin to produce core dumps by including

   error_start=x:\path\to\dumper.exe
   
   in your CYGWIN environment variable (see here in section "dumper" for more information). If you didn't do this, you will only get a stacktrace -- which may also help you in diagnosing the problem, though.

2. Start gdb as follows to attach it to a core dump file:

   gdb myexecutable --core=mycorefile
   
   You can now use the usual gdb commands to print a stacktrace, examine the values of variables, and so on.

1. Yes, cygwin creates a.exe.stackdump files by default. You need to configure it to create cores as well (Martin's answer covers that).
2. A simple tutorial on core dump debugging can be found here