[PATCH] ubsan: Do not run the testsuite if ubsan does not work at all

[Eric Botcazou]

> What errors do you get?  Just curious.

Something along of "cannot load libtsan.so.0" and this comes from PR 58867.

> That said, I think your patch is fine.

Thanks, installed after testing on x86-64/Linux.

-- 
Eric Botcazou