Future support of constexpr math functions

[Timothy Wrona]

I assume with a "pragma" you'd be able to specify different rounding modes
for different sections of the program at compile time?

Either way compile-time math is so useful it seems ridiculous for the
standard to explicitly state it is not allowed at all.

On Fri, Feb 14, 2020 at 11:06 AM Marc Glisse <marc.glisse@inria.fr> wrote:

> On Fri, 14 Feb 2020, Timothy Wrona wrote:
>
> > Just curious, but why couldn't you decide the rounding mode at compile
> time
> > and pass the desired rounding mode as an argument to the compiler?
>
> Usually we need several different rounding modes in the same program.
>
> The draft of the future C standard does have some pragma that might help,
> but seeing how hard it is to find implementations of pragma fenv, that may
> be optimistic.
>
> --
> Marc Glisse
>