Bug#634821: libgcc1: filename change breaks old gcc

[Jonathan Nieder <jrnieder@gmail.com>]

Package: libgcc1
Version: 4.6.0-12
Severity: important
Justification: breaks related software
X-Debbugs-Cc: Andrew Chittenden <andyc@bluearc.com>

Hi,

As Andy noticed[*], moving libgcc_s.so.1 from /lib to /lib/$arch
breaks versions of gcc from before that move.

 $ echo 'int main(void) { return 0; }' | gcc-4.3 -x c -
 /usr/bin/ld: error: cannot open /usr/lib/gcc/x86_64-linux-gnu/4.3.5/libgcc_s.so: No such file or directory
 /usr/bin/ld: error: cannot open /usr/lib/gcc/x86_64-linux-gnu/4.3.5/libgcc_s.so: No such file or directory
 collect2: ld returned 1 exit status

The cause: such gcc versions include a symlink with the path to
libgcc hardcoded.

 $ readlink /usr/lib/gcc/x86_64-linux-gnu/4.3.5/libgcc_s.so 
 /lib/libgcc_s.so.1

(The same considerations apply to libgomp.so.1, though that might
be less noticeable.)

Questions:

1. Is there any GCC command-line option that people can use to work
   around this kind of thing (e.g., to add a directory to the front of
   the search order)?

2. Would it make sense to introduce a new package libgcc1-multiarch
   and make libgcc1 into a compatibility package that ships a symlink

	/lib/libgcc_s.so.1 -> /lib/$arch/libgcc_s.so.1

   for the sake of smooth partial upgrades?

3. Any other thoughts?

Thanks and hope that helps,
Jonathan

[*] http://bugs.debian.org/629819