[Bug target/47558] 163267 breaks exception traceback in xplor-nih

["iains at gcc dot gnu.org" <gcc-bugzilla at gcc dot gnu dot org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47558

--- Comment #14 from Iain Sandoe <iains at gcc dot gnu.org> 2011-02-01 14:37:39 UTC ---
the difference caused by including a reference to "/usr/libgcc_s.xxx" is to
allow a libgcc_s appearing in a DYLD_LIBRARY_PATH (or a fallback path in the
compiler's list) to over-ride ... 

have you (or does the build process) set a DYLD_LIBRARY_PATH ?

another possibility is a corrupted, stale or erroneous build of one of those
libraries that refers to _Unwind_xxxx in FSF libgcc_s.1.dylib (how it manages
that would bear some inspection).

I've checked recent trunk for 10.6 and
(a) libgcc_ext.dylib does NOT export _Unwind_xxxxx
(b) /usr/libgcc_s.10.5.dylib is just a stub pointing to libSystem.dylib.

so if you've manage to resolve _Unwind_xxxx from FSF libgcc_s then the two top
choices are:
either there is a dodgy -L in the build process 
or you've got a DYLD_LIBRARY_PATH somewhere ...