Print warning when timings are run in non optimized executable
CMake automatically enables O3 optimization and adds the definition NDEBUG when executed with DCMAKE_BUILD_TYPE=Release. We can make use this to print warnings in timing codes when NDEBUG is not defined to signal the user that he can not rely on the timings (since missing defintion of NDEBUG is a hint that optimization is not enabled).
Related #94 (closed)
@lfilippo Do you know a convenient/fast way to obtain a list of all cpp files that do timings in some sense?