The Intel compiler(s) -- I don't know whether ifort and icc are really distinct -- may produce better code than GCC, and vice versa. The bottom line I got for

The Intel compiler(s) -- I don't know whether ifort and icc are really distinct -- may produce better code than GCC, and vice versa. The bottom line I got for a set of Fortran benchmarks on SKX was essentially a tie with options as similar as I could make them. (It's a set that seemed to be used for marketing proprietary compilers.) If icc is as reliable as ifort, I wouldn't want to build my OS with it.