z/OS and libc

I'm working on continuing to port perl5 to z/OS.  One test that is 
failing is beyond my knowledge level.  The Dynaloader module has a 
function dl_findfile() which looks for libraries in the path.  It is 
expecting to find libc at least, but is finding nothing.

This test does not work on several platforms, even some Unix-like ones, 
and my guess is it doesn't work on z/OS either.  But I am hoping someone 
can give me more information.

One of the comments in the perl source says:
     # On OS/390, libc.a doesn't really hold anything at all,
	
And that makes me think that looking for it (and perhaps any Unix-y 
library) is futile.