[PATCH] clang-cl: Map /Zi[-] to -f[no-]builtin

[Reid Kleckner]

  /Zi and /ZI have to do with pdb debug info.  :)  /Oi does intrinsics.  I suppose we could map /Oi- to -fno-builtin.

  We could map /Zi to -g (and Zi- to g0), but I don't see much value in it.

http://llvm-reviews.chandlerc.com/D1328