Reinstating stdint.h in test/CodeGen/const-init.c

In October (in r84160) the #include<stdint.h> in
test/CodeGen/const-init.c was replaced with an explicit definition of
intptr_t. From what I gather, this was done to get the test to succeed
on Windows, where a host stdint.h is not implemented and clang, in
hosted mode, blindly attempts to include one anyways.

Explicitly defining intptr_t in the file has the problem of relying on
the built-in macro, __INTPTR_TYPE__, which I would consider an
implementation detail of stdint.h, one that I'd like to remove (but I'll
save that discussion for another thread).

I'd like to propose an alternate fix. See the attached patch. It runs
the test in freestanding mode, forcing the inclusion of clang's stdint.h
instead looking for a hosted one. And, more importantly, it doesn't rely
on any built-in macros.



const-init-intptr-def.r89241.patch (534 Bytes)

It works on Windows.

Alright. Committed as 89609, then.