Allow Java's ELF symtab reader to use separate debuginfo files

[Andrew Haley]

Andrew John Hughes wrote:
> 2009/12/9 Andrew Haley <aph at redhat.com>:
>> This is https://bugzilla.redhat.com/show_bug.cgi?id=541548
>> The symptom is that jmap doesn't work because target libraries are stripped.
>> The fix is to allow the symtab reader to use the separate debuginfo files
>> that are available for all (AFAIK) GNU/Linux distributions.
>>
>> I'll commit this to the IcedTea repo, with a view to pushing it upstream
>> to OpenJDK if it works on all distros.
> 
> It would be good to see this upstream.  The obvious compatibility
> issue I can see is hardcoding /usr/lib/debug.  Passing that in from
> the Makefile, thus allowing to be overridden if necessary, might be
> better.
> i.e.
> 
> static const char debug_file_directory[] = "/usr/lib/debug";
> 
> becomes
> 
> #ifndef DEBUG_FILE_DIRECTORY
> #define DEBUG_FILE_DIRECTORY "/usr/lib/debug"
> #endif
> 
> with apppropriate logic in the OpenJDK makefile(s).

I think this directory is generally assumed to be hard-coded everywhere.  I
will make such a change if this patch won't be committed otherwise, but I do
not believe that it will ever be used.

> Only other comment is that your ChangeLog should refer to openjdk, not
> openjdk-ecj as we want this for all builds. The patch itself is
> correct, it's just the ChangeLog.

Yeah, I noticed this already.

Thanks,
Andrew.