How to disable OpenMP directives in a nice way?

Question

I have C++ code with OpenMP pragmas inside. I want to test this code both for multithread mode (with OpenMP) and in single thread mode (no OpenMP).

For now, to swit

Answer 1

The way such things are usually handled (the general case) is with #defines and #ifdef:

In your header file:

#ifndef SINGLETHREADED
#pragma omp
#endif

When you compile, add -DSINGLETHREADED to disable OpenMP:

cc  -DSINGLETHREADED  code.c