>> A quick GCC test suggests this is how they do it ("#define __ARM_ARCH_PROFILE 65" for Cortex-A15, which is also dodgy in C++ mode, but less so). > I'd prefer a quoted char. Me too. From the ACLE wording, I'd expect sizeof(__ARM_ARCH_PROFILE) == 1 in C++ mode. Cheers. Tim. http://reviews.llvm.org/D4146