Re: [patch 2/2] Implement multi-component --with-auto-load-dir

[Jan Kratochvil <jan dot kratochvil at redhat dot com>]

Hi Joel,

On Wed, 09 May 2012 22:17:43 +0200, Joel Brobecker wrote:
> I really do not understand what this new setting is about.  Can you
> just give me a quick concrete example of what wouldn't work with
> the current code, and how this gets solved by the new setting?

With Fedora scl-utils ("alternative packaging") you have both regular
	/usr/share/gdb/auto-load/
and also the "alternative"
	/opt/rh/upgradeset/root/usr/share/gdb/auto-load/

as there is both regular GDB and the "upgradeset" (=newer) GDB.
While for example libstdc++ Pretty Printers is located in both
(coincidentally, because it is bundled with GDB in some versions):
	/usr/share/gdb/auto-load/usr/lib64/libstdc++.so.6.0.16-gdb.py
	/opt/rh/upgradeset/root/usr/share/gdb/auto-load/usr/lib64/libstdc++.so.6.0.16-gdb.py

with the latter variant having more recent GDB macros and therefore preferred
by newer GDB located in
	/opt/rh/upgradeset/root/usr/bin/gdb
which is using its default configured
	/opt/rh/upgradeset/root/usr/share/gdb/auto-load/

it will be a problem that
	/usr/share/gdb/auto-load/lib64/libglib-2.0.so.0.3000.3-gdb.py

is not loaded at all because it does not have any "upgradeset" variant in
	/opt/rh/upgradeset/root/usr/share/gdb/auto-load/
.

This means we need multiple auto-load/ directories (unless we want to
introduce some shell scripting symlinks magic etc.).


> I was hoping at some point that this would allow us to have auto-loaded
> scripts without having to have the same path structure in the auto-load
> directory as in the executable (by that, I mean that if you are
> debugging /work/build/gcc-feature-a/gcc/cc1, you don't need to have
> cc1-gdb.gdb defined in your auto-load directory as
> auto-load/work/build/gcc-feature-a/gcc/cc1-gdb.gdb. It'd just be
> sufficient to have cc1-gdb.gdb defined in your scripts-directory.
> But looking at the code, I don't think that this is what we are
> talking about.

I do not think these two features are related.  I can think about some ideas
but I do not see a super-elegant one for it now.


Thanks,
Jan