#include <boost/config.hpp> #if defined(BOOST_MSVC) && defined(NDEBUG) # define BOOST_ASSUME(e) { BOOST_ASSERT(e); if (e); else __assume(0); }
There's a real problem with your solution, however: you evaluate the expression twice. Won't the simpler, more direct form work?
Of course, that was a silly mistake. It should be: #include <boost/config.hpp> #undef BOOST_ASSUME #if defined(BOOST_MSVC) && defined(NDEBUG) # define BOOST_ASSUME(e) { BOOST_ASSERT(e); __assume(e); } #else # define BOOST_ASSUME(e) BOOST_ASSERT(e) #endif I hope that is fine now.
Interesting. I'd have thought that calling __assume(0) was useless, but it tells the optimizer that the else clause won't occur. I wonder if that will work at all or as well as BOOST_ASSERT(e); __assume(e);
It's not useless, see my previous posts in the thread for examples of code generated with and without __assume(0). cheers, Marcin