[PATCH] D45383: Limit types of builtins that can be redeclared.

[Erich Keane via Phabricator via cfe-commits]

erichkeane added a comment.

In https://reviews.llvm.org/D45383#1065999, @compnerd wrote:

> I know that the Windows SDK definitely declares the `__va_start` function.  Did you try building something like swift against the Windows SDK with this change?


Are we sure it declares it, and not just #define's it?  If it actually declares it, there is no way it can currently build in certain C modes due to the issue I'd mentioned previously.


https://reviews.llvm.org/D45383