[opensource-dev] Building viewer-release on OS X.

[Ash Qin]

> Did you install Command Line Tools with Xcode and CMake?

Yes.

> (from your logs)
> -- The C compiler identification is unknown
> -- The CXX compiler identification is unknown

That's only because I defined the CC and CXX environment variables to
use LLVM-GCC through ccache using:

export CXX=/usr/local/opt/ccache/libexec/llvm-g++-4.2
export CC=/usr/local/opt/ccache/libexec/llvm-gcc-4.2

This is because I am aware that viewer-release will not build under
Clang. If you look in the build log, it uses those compilers fine.
Also, no difference when not using ccache.

> That's not good. :O

I don't know why it states unknown.

Ash