Re: CURRENT: CLANG 3.3 and -stad=c++11 and -stdlib=libc++: isnan()/isninf() oddity

On 13.7.2013 13:12, David Chisnall wrote:
> On 12 Jul 2013, at 22:47, "O. Hartmann" <ohartman_at_zedat.fu-berlin.de> wrote:
>
>> Obviously not really fixed, but even worse:
>>
>> if I use in C code (C99, using clang 3.3 on FreeBSD 10.0-CURRENT/amd64
>> revision 253287) isnan(x) where x is a "const double", I receive now
>> the following error (which doesn't appear on previous versions):
>
> Thanks.  This is now fixed, however the _Generic() usage that we had there is also present in tgmath.h, and so this file will also need to be fixed in the same way.
>
> I've now tested the macros with clang/c99, clang/c11, clang/c++98 and clang/c++11, and gcc/c89 and they all seem to work for unqualified, const, volatile, and const-volatile qualified types.
>
> I've added Ed to the cc: list, as he wrote this code in tgmath.h.
>
> David
>

Instead of listing all possible type qualifier combinations (like in 
r253319), how about using a comma operator to strip away type 
qualifiers? Since only the result type of the expression matters and it 
isn't evaluated at all.

like:

#define __fp_type_select(x, f, d, ld) _Generic((0,(x)),

Pasi