If you add '-ffast-math' to the compiler parameters in his godbolt link you get the 'right' answer. Doing that means the division is done with the 'divsd' instruction, which clang uses even without the 'fast-math' flag.
That doesn't mean it's necessarily the right thing to do though.
Clang can be made generate the same code as the 'broken' gcc output by declaring the variables as 'long double' instead of 'double'.
So I think this is where the issue lies?
That doesn't mean it's necessarily the right thing to do though.
Clang can be made generate the same code as the 'broken' gcc output by declaring the variables as 'long double' instead of 'double'. So I think this is where the issue lies?
Edit: godbolt link requiring large monitor: https://godbolt.org/z/tFiZwW