> With the switch to clang, binary size dropped about 8% while performance mostly stayed the same. Startup time improved a bit,
Also I can imagine it might be nice to use the same compiler on different OSes, and gcc is very much a 2nd class citizen on mac.
I think it's pretty acceptable, if you're writing C. As you can see, C++ support is only partially completed (no exceptions!). But you're right, Clang on Windows gets constantly improved.
The creation of good debugging information (MSVC's /Zi or even /ZI option) is also missing. For a first class citizen, support of the (undocumented) PDB format is a requirement in my opinion.
You can now build a fairly well-functioning chrome binary, from visual studio, with clang/llvm, without source code changes.