Re: [PATCH v2] gdb/configure.ac: Add option --with-additional-debug-dirs

[Eli Zaretskii <eliz@gnu.org>]

> Cc: Tom Tromey <tom@tromey.com>
> Date: Wed,  4 Oct 2023 15:31:02 -0300
> From: Thiago Jung Bauermann via Gdb-patches <gdb-patches@sourceware.org>
> 
> If you want to install GDB in a custom prefix, have it look for debug info
> in that prefix but also in the distro's default location (typically,
> /usr/lib/debug) and run the GDB testsuite before doing "make install", you
> have a bit of a problem:
> 
> Configuring GDB with '--prefix=$PREFIX' sets the GDB 'debug-file-directory'
> parameter to $PREFIX/lib/debug.  Unfortunately this precludes GDB from
> looking for distro-installed debug info in /usr/lib/debug.  For regular GDB
> use you could set debug-file-directory to $PREFIX:/usr/lib/debug in
> $PREFIX/etc/gdbinit so that GDB will look in both places, but if you want
> to run the testsuite then that doesn't help because in that case GDB runs
> with the '-nx' option.
> 
> There's the configure option '--with-separate-debug-dir' to set the default
> value for 'debug-file-directory', but it accepts only one directory and not
> a list.  I considered modifying it to accept a list, but it's not obvious
> how to do that because its value is also used by BFD, as well as processed
> for "relocatability".
> 
> I thought it was simpler to add a new option to specify a list of
> additional directories that will be appended to the debug-file-directory
> setting.

Thanks, the documentation parts are okay.

However, I wonder: on MS-Windows, the "colon-separated list" becomes
"semi-colon separated list", and I have an old and annoying problem
with 2 similar configure-time options, --with-auto-load-safe-path= and
--with-auto-load-dir=, which fail to communicate semi-colon separated
lists to gdb/configure, and require me to manually edit gdb/config.h
and rebuild.  So I wonder whether this new option will have the same
problem, and whether we could perhaps take this opportunity for fixing
this?

This is https://sourceware.org/bugzilla/show_bug.cgi?id=18898, btw.

Reviewed-By: Eli Zaretskii <eliz@gnu.org>