Why 0.1 + 0.2 == 0.3 in D?

Question

assert(0.1 + 0.2 != 0.3); // shall be true

is my favorite check that a language uses native floating point arithmetic.

C++

Answer 1

It's probably being optimized to (0.3 != 0.3). Which is obviously false. Check optimization settings, make sure they're switched off, and try again.