Here is patch that allows valgrind to run Guile under Linux non-IA64 architectures. It also fixes a potential leak in threads.c where a pthread attribute was not destroyed.
Note that libgc still generates lots of warnings. For now, I've just been suppressing all warnings from libgc, and I'm happy to report that Guile doesn't seem to cause any issues on my system (Linux/AMD64). But it's certainly possible that the suppressions could mask a legitimate issue. Attached are the patch and suppressions file (which also suppresses a false positive in libunistring).
guile.supp
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valgrind.patch
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