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> ICC has been found to be very lacking compared to both gcc and clang Who found that? For processing intensive tasks, I routinely get a 30% reduction in run

> ICC has been found to be very lacking compared to both gcc and clang Who found that? For processing intensive tasks, I routinely get a 30% reduction in run time using ICC - mainly owing to ICC's aggressive vectorization. Rarely, I'll have to do some shenanigans to force it to work correctly. Very rarely. I use clang when developing because the error messages are miles ahead of anybody else, then produce a 'stable' GCC version and an ICC version. If the ICC version produces the same results as the GCC version for the test suite, I exclusively use the ICC version.

Joky 12y ago
"processing intensive tasks" may not be the one to expose all the corner cases of C and C++?
gh02t 12y ago
In my experience, `icc/pc` and `ifort` give a significant speed boost for numerical code (on Intel hardware at least), but for more general purpose code it's not really very impressive. However, the related products like `ipp` and `mkl` are where Intel has a real advantage. My experience has been that `mkl` in particular is dramatically faster than vanilla LAPACK and friends and still quite a bit faster than more optimized variants like ATLAS. But, you don't need to use the Intel compilers to use those libraries, you can use them with gcc as well.