Matthew Knepley emailed the following on 14/02/12 00:34:

As a first step - can we add OpenMP support to PETSc conf? Lawrence made a first pass at this: https://bitbucket.org/wence/petsc-dev-omp/src/52afd5fd2c25/config/PETSc/pack... It does need extending because it will fail in it is current state for a number of compilers. I am guessing we would have to reimplement something like ax_openmp or similar...what is the right thing to do here?

Can you explain the right test?

The definitive test would be to try to compile a test code: eg int main(){ #ifndef _OPENMP choke me #endif return 0; } The OpenMP standard specifies that the preprocessor macro name _OPENMP should be set. As for the actual compile flag ... reading FindOpenMP.cmake you can see that they take the test compile approach as above, and they have a list of candidates (OpenMP_C_FLAG_CANDIDATES) which are tested. Another option would be to allow --with-openmp[=magic_flag] for the odd compiler not recognised. For example I notice that the Fujitsu compiler is not listed in FindOpenMP.cmake. Cheers Gerard