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by liuliu 5951 days ago
I am currently switching between gcc and clang for my codebase. The performance is mixed. For some programs (2-level hashtable, for example), the clang version got about 50% speed up against gcc and icc. But other programs (sobel filter for example), clang version slows down about 25% (against gcc 4.4). The result certainly machine specific, but I think clang can do better in a long run.
1 comments

Although cryptic, I'd say that gcc's error messages are manageable. I'd hold other factors, such as performance of compiled code - across platforms - to be more important. Alternatively, they could improve on the C++ template error reporting (when they get around to taking C++ support beyond alpha) and that may be enough to sell me.

a quick search yields http://clang.llvm.org/performance.html (favourable, but somewhat skewed results). http://forums.cocoaforge.com/viewtopic.php?f=10&t=21016 indicates improved compile times, but it's purely anecdotal.

That said, does anyone else have any experience moving a performance-centric or cross platform project to clang?

If clang could come up with better C++ template error messages that would be really sweet. STL related error messages in g++ (and MSVC) are really hard to figure out, especially when C++ is not your main language; so you're not exposed to those problems on a daily basis.