[cfe-dev] C++ objects sometimes initialized to zero before constructor is called?

[Ryan C. Gordon]

> Note that new B() triggers zero-initialization, because it calls a
> non-user-provided default constructor using empty parens. The other
> cases do not, either because they call a user-provided constructor or
> because they use default-initialization rather than value-initialization.

That was totally it! I removed a "()" from a macro, and now the whole 
game is running when built with clang.

Thanks so much for a fast and detailed response. After reading this, I 
was up and running within about 60 seconds.  :)

--ryan.