This should fix the bad behavior we had where setGlobal would only get rewritten
by having its call to setattr() get inlined, and having setattr() then think it
was being called directly.  This was both brittle (only worked on release builds)
and incorrect (there were checks that happened before calling into setattr, which
needed to be emitted as guards).

I had hacked in an attribute((always_inline)) to at least deal with the brittleness,
but this should be a fix for real.  And let us reenable the gcc builds.