Speed of math function atan: comparison D and C++

[jmh530]

On Tuesday, 6 March 2018 at 18:41:15 UTC, H. S. Teoh wrote:
>
> The fix itself may be straightforward, but how to do it without 
> breaking tons of existing code and provoking user backlash is 
> the tricky part.
> [snip]

Ah, I see what you're saying. People may be depending on the 
extra accuracy for these functions.

Would just require something like

double sin(double x) @safe pure nothrow @nogc
{
     version (FP_Math) {
         ///double sin implementation
     } else {
         return sin(cast(real) x);
     }
}