Re: 32-bit double and long double

[Rich Felker <dalias@libc.org>]

On Mon, Nov 26, 2018 at 06:25:04PM +0300, Eugene Sharygin wrote:
> Hi,
> 
> We're using Musl on a platform where both float, double, and long double
> are in IEEE-754 binary32 format, and I'm wondering if a patch that lifts
> some of the assumptions made regarding widths of floating-point types
> would be accepted.

No, musl only supports (roughly) Annex-F conforming environments, with
IEEE single and double and a long double type with IEEE-compatible
semantics. Such patches won't be accepted upstream.

Is there a reason your target is defining double in an unuseful and
incompatible way rather than doing hard-single and soft-double? If you
have any control over the choice of ABI, I think the latter makes a
lot more sense.

Rich


> Here is the relevant excerpt from the documentation:
> 
> > Floating-point formats are assumed to be IEEE-754 binary32 format for
> > float and IEEE-754 binary64 for double.
> >
> > Supported long double formats: IEEE-754 binary64 (ld64) and x86 80 bit
> > extended precision format (ld80) are fully supported and there is
> > partial support for IEEE-754 binary128 (ld128).
> 
> Eugene