I am trying to run this cmake file on my system which has ubuntu 7.10 installed and has a dualcore. One complication is that I need to include -fopenmp flag to avoid the errorslike "undefined references to the OPENMP_THEREAD_START".
If it were a makefile I would simiply add the flag at the gcc command, it's a cmake with which I am not very familiar.

How can I add -fopenmp flag in cmaket?
Thanks in advance.