On Wed, 6 Mar 2013, Michele Martone wrote: > . CFLAGS for gcc: > "-O3 -pipe -march=native -mtune=native -mavx -std=c99 -fno-unroll-loops" > . CFLAGS for icc: "-O3 -xAVX -restrict -unroll=0" This makes a comparison "unfair" since the two compilers use different optimization restrictions for floating-point operations by default (GCC is conservative, and thus more restricted in optimizations). See the documentation for -ffast-math GCC option, and floating-point flags in the ICC help (e.g. options -fp-model and -mp). Alexander
