It depends a lot on the use-case. For my hobby project (numerical stuff, C++) I got a speedup of more than 10% by moving to Clang. Huge stuff. I spend ~50% of my time in one hot function, though, and it's entirely possible that GCC generated better code for the rest of the project.
As usual, the only reliable way to know which compiler generates better code for your program is to run benchmarks.
For what it's worth, I wasn't blown away by the compile times or error messages when I moved to Clang. I think GCC is getting a lot better, but I'd also learned to live with its failings regardless.
As usual, the only reliable way to know which compiler generates better code for your program is to run benchmarks.
For what it's worth, I wasn't blown away by the compile times or error messages when I moved to Clang. I think GCC is getting a lot better, but I'd also learned to live with its failings regardless.