Clang vs GCC - which produces better binaries? [cl

Question

I'm currently using GCC, but I discovered Clang recently and I'm pondering switching. There is one deciding factor though - quality (speed, memory footprint, reliability) of binaries it produces - if gcc -O3can produce a binary that runs 1% faster or takes 1% less memory, it's a deal-breaker.

Clang boasts better compile speeds and lower compile-time memory footprint than GCC, but I'm really interested in benchmarks/comparisons of resulting compiled software - could you point me to some or describe your experiences?

Answer 1

Phoronix did some benchmarks about this, but it is about a snapshot version of Clang/LLVM from a few months back. The results being that things were more-or-less a push; neither GCC nor Clang is definitively better in all cases.

Since you'd use the latest Clang, it's maybe a little less relevant. Then again, GCC 4.6 is slated to have some major optimizations for Core 2 and i7, apparently.

I figure Clang's faster compilation speed will be nicer for original developers, and then when you push the code out into the world, Linux distro/BSD/etc. end-users will use GCC for the faster binaries.