Top-of-trunk clang from http://llvm.org/apt/ takes ~2.1 seconds on my machine to preprocess the file to /dev/null. warp (compiled with -O4 -frelease -fno-bounds-check) takes ~2.8 seconds.
So this test case is faster with clang even without precompiled headers. It is hard to make a benchmark for clang's precompiled headers because the AST is lazy-loaded from the PCH. You would have to actually have code use values from the header.
EDIT: I forgot another advantage of clang: the preprocessing and compilation and assembly are all done within the same process, eliminating process creation overhead.
Top-of-trunk clang from http://llvm.org/apt/ takes ~2.1 seconds on my machine to preprocess the file to /dev/null. warp (compiled with -O4 -frelease -fno-bounds-check) takes ~2.8 seconds.
So this test case is faster with clang even without precompiled headers. It is hard to make a benchmark for clang's precompiled headers because the AST is lazy-loaded from the PCH. You would have to actually have code use values from the header.
EDIT: I forgot another advantage of clang: the preprocessing and compilation and assembly are all done within the same process, eliminating process creation overhead.