Clang's MemorySanitizer in userland?

Has anybody successfully used Clang's MemorySanitizer in userland?

I'm trying to search for uinitialized memory usage in ZFS.  Rather
than use KMSan in the kernel, I would prefer to use ztest in userland.
But I'm having trouble getting it to work.  The main limitation is
that every single shared library needs to be rebuilt with
MemorySanitizer enabled.  Another limitation is that I haven't figured
out how to properly link shared libraries that are using
MemorySanitizer.  And a third limitation is that MemorySanitizer will
alert for false positives for syscalls that it doesn't know about.
sysctl seems to be one of those.

So if anybody has yet used it successfully, I'd love to see your work
as an example.