Re: Post mortem debugging for Windows CE

[Danny Backx <danny dot backx at scarlet dot be>]

After a good deal of actually using gdb to debug itself (as I did a lot
in these days), here is where I am at :

dannypc: {1013} gdb/gdb examples/callstack.exe examples/Ce042809-01.kdmp
GNU gdb 6.8
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This GDB was configured as "--host=i686-pc-linux-gnu
--target=arm-mingw32ce"...

warning: exec file is newer than core file.
Error while mapping shared library sections:
coredll.dll.0409.mui: No such file or directory.
Error while mapping shared library sections:
coredll.dll: No such file or directory.
Symbol file not found for coredll.dll.0409.mui
Symbol file not found for coredll.dll
Core was generated by `callstack'.
Program terminated with signal 11, Segmentation fault.
[New process 594225230]
#0  0x00011178 in fibo (n=2) at callstack.c:11
11                      return *i;
(gdb) info sharedlibrary 
>From        To          Syms Read   Shared Object Library
                        No          coredll.dll.0409.mui
                        No          coredll.dll
(gdb) 

It doesn't print from- and to-addresses in this example. I believe that
this is because solib_map_sections can't read the DLL files (they're
target DLLs from Windows CE, I don't have them on my host). So it fails
in :
  scratch_chan = solib_open (filename, &scratch_pathname);

  if (scratch_chan < 0)
    {
      perror_with_name (filename);
    }

Am I right in concluding that this is the way it should work ?

Does anyone have tricks to produce some fake DLL file for this type of
scenario ?

	Danny


On Tue, 2009-05-05 at 17:53 +0100, Pedro Alves wrote:
> On Tuesday 05 May 2009 14:30:51, Danny Backx wrote:
> 
> > It looks like I'm getting close to something that works. Small session
> > below. Cleanup and more testing are certainly required.
> 
> This is looking very good!
> 
> > I'm about to look into your suggestion about .module sections.
> > 
> > How can I observe the effect of that ? How can I test ?
> 
> The .modules sections would contain the list of loaded modules
> at the time of the crash.  So, 'info sharedlibrary' should list the same
> list of dlls as the live inferior had, and their load addresses should
> be the same.
> 
> You could tweak your test app to move the crashing code into a mini
> dll you'd write.  Use 'set sysroot' or 'set solib-search-path' command to
> point GDB at the host copy of the dll, and load the minidump
> into GDB.  GDB should be able to show you the crash site source code,
> backtracing from the function in  the dll should work, and
> 'info sharedlibrary' should report correct data, of course.
> 
-- 
Danny Backx ; danny.backx - at - scarlet.be ; http://danny.backx.info