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

[jmh530]

On Tuesday, 6 March 2018 at 17:51:54 UTC, H. S. Teoh wrote:
> [snip]
>
> I'm not advocating for getting *rid* of 80-bit float support, 
> but only to make it *optional* rather than the default, as 
> currently done in std.math.
>
>
> T

Aren't there two issues: 1) std.math functions that cast to real 
to perform calculations, 2) the compiler sometimes converts 
things to real in the background when people don't want it to.

Number 1 seems straightforward to fix. Introduce new versions of 
the std.math functions for float/double and the user can cast to 
real if the additional accuracy is necessary.

Number 2 would require a compiler switch, I imagine.