[PATCH] Preserve ::is{inf,nan}{f,l} prototypes even for C++11 and later

[Carlos O'Donell]

On 02/23/2016 10:23 AM, Andreas Schwab wrote:
> That doesn't compile on platforms where long == long double, since they
> do not declare any *l functions (arm, hppa, mips/o32).
> 
> test-math-isinff.cc: In function 'int do_test()':
> test-math-isinff.cc:33:22: error: 'isinfl' was not declared in this scope
>        || isinfl (1.0L)
>                       ^
> test-math-isinff.cc:37:22: error: 'isnanl' was not declared in this scope
>        || isnanl (2.0L)
>                       ^

I'll fix this shortly and backport to 2.23 branch.

Any suggestions for how you want to fix it are welcome.

Cheers,
Carlos.