Kevin Ryde wrote:
> Claes Wallin <clawa570+gmane@student.liu.se> writes:
>>           Demand C99 for math functions.
> 
> Which ones are missed otherwise?

From /usr/include/iso/math_c99.h:

#if defined(_STDC_C99) ...
...
#define isinf(x) ...

> 
>> +AC_PROG_CC_C99
> 
> I'm worried that will turn off good things in gcc.  I'd much rather
> leave the compiler in the default mode, or whatever mode the user has
> asked for with CFLAGS.

It seems that isinf is c99, and that earlier gcc:s supported it in isoc
as a GNU extension. If we're using c99, why not specify it? What good
things will be turned off?

   /c