[Bug c++/49813] [C++0x] sinh vs asinh vs constexpr

[paolo.carlini at oracle dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49813

--- Comment #16 from Paolo Carlini <paolo.carlini at oracle dot com> 2011-07-22 11:40:07 UTC ---
(In reply to comment #14)
> There is also a using ::asinhf but still std:: provides an overload.

So? This is what C++0x says we should have.

As regards a complete testcase, I gave two, one using <math.h>, one a *real
world* piece of C++0x code, compiled with -std=c++0x on Linux.

#include <cmath>

int main()
{
  constexpr double cds  = std::sinh(1.0);  // Ok
  constexpr double cdas = std::asinh(1.0); // Not Ok.
  double das = std::asinh(1.0);            // Ok.
}

we don't want those inconsistencies.

By the way, I find your:

constexpr double cdas = __builtin_asinh(1.0);

very interesting. Looks like really the front-end is doing something strange
wrt declarations of C99 functions: if <math.h> provided by glibc is include
then the declarations are definitely there, in strict c++0x mode too, but the
front-end is trying to invent something on its own, disregards those
declarations somehow, but *only* when dealing with constexpr data, not
otherwise.