http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60997
--- Comment #3 from Mircea Namolaru <mircea.namolaru at inria dot fr> --- It is not that -floop-interchange is disabled, but the code received by graphite is different if the option -fopenmp is enabled. In this case the check for data dependencies required by loop-interchange fails. I wil check more in depth if the data dependencies are right in this case or there is a problem with them (but probably not). I guess that the problem is the same for vectorization (but there the data dependencies for vectorization are not checked by graphite).