Just to make sure again, is the debug build better than the release build in terms of correctness? How about speed? I know that the former takes more size than the latter.
If the speed is concern, the debug is slower than release build.
What do you mean by correctness?
Gives expected/correct results out of the implemented algorithm.
They're both correct in that sense. Debug has runtime checks and no optimisation so is slower.
Some programs will work in debug mode but fail in release mode. If that is the case the program is not implemented correctly.