long double and GLIBCPP_CHECK_MATH_SUPPORT

[Benjamin Kosnik]

you are welcome! that was done for powerpc specifically, but i think it 
works on alpha too. 

although that's definitely the direction i want to go, i'm not quite sure 
it's the most elegant. In particular, I don't really want to use the 
mangled macros for each of the long double functions in particular, 
because it will be a mess. (ie, sinl -> _GLIBCPP_HAVE_SINL in std_cmath.h). 

if everybody else is in agreement, please post your patch.

thanks
benjamin


> 	Thanks for the GLIBCPP_ENABLE_LONG_DOUBLE test.
> 
> 	May I create a patch to acinclude.m4 moving the
> GLIBCPP_CHECK_MATH_SUPPORT tests after the GLIBCPP_ENABLE_LONG_DOUBLE test
> and avoid the basic C math functions long double tests if
> GLIBCPP_ENABLE_LONG_DOUBLE already failed?

 yes