Re: [bug #57173] Feature request: zeta function for complex arguments

[Gerard Jungman]

On 11/5/19 11:26 AM, Mark Galassi wrote:
> > > > > > "Patrick" == Patrick Alken <address@hidden> writes:
>
>
>      Patrick> I don't think any progress was made on this
>
> One update to the discussion from back then is that C++11 has formalized
> data compatibilty between the C11 _Complex type and the C++ complex
> class.  This also raises the architectural question of whether GSL might
> want to use C's complex type.

Although, strangely enough, they made support for
complex types optional. Does anybody know the
rationale for this decision? This kind of
back-peddling seems very strange.

I have been using the new types myself in C code,
for several years. Of course, gcc and clang are not
going to drop support for the types. But I worry that
this "optionality" means they may not get the love
and attention they need. Or worse, that something
weird might happen leading to a divergence of
implementations.


It would be good to move to the standard, if we know
it is not going to deteriorate in some way, and that
there are no hidden issues with the implementations
as they exist now. There are some weird hidden
issues, like the meaning and consequences of
the CX_LIMITED_RANGE pragma.

At the very least, it would be good to read the normative
parts carefully. Annex G of either the c17 draft standard
(n2176) or the c11 draft standard (n1570). The two seem
to be identical, but I have not taken out a microscope.