If you run into troubles, it is always a good habit to report the following information:

• the way build.mrcc was invoked
• the output of build.mrcc
• compiler version (for example: ifort -V, gfortran -v)
• blas/lapack versions
• as well as gcc and glibc versions

as well as the value of the relevant environmental variables, such OMP_NUM_THREADS, etc.

This information helps us a lot when figuring out what is going on with your compilation :)