TR29124 C++ Special Maths - Make <math.h> pull functions into global namespace.

[Jonathan Wakely]

On 20/01/16 20:30 -0500, Ed Smith-Rowland wrote:
>Now that libstdc++ installs a proper math.h we can piggyback on that 
>to put in the last bit of TR29124.
>
>This patch adds the math special functions to c_compatibility/math.h 
>in the global namespace.
>I remove the XFAILs from the compile_2.cc tests.
>
>This converts 21 XFAILs into 21 PASSes.
>
>Tested on x86_64-linux.
>
>I understand if this is too late.
>I'll put it up on trunk and backport after stage 1 reopens.
>
>Meanwhile I'll commit this to the tr29124 branch.

I'm inclined to say the change is OK for trunk now. We've added math.h
and we've added the special functions, it would be good if the two new
things work together.

However ...

>Index: include/c_compatibility/math.h
>===================================================================
>--- include/c_compatibility/math.h	(revision 232610)
>+++ include/c_compatibility/math.h	(working copy)
>@@ -75,70 +75,71 @@
> #endif
>
> #if __STDCPP_WANT_MATH_SPEC_FUNCS__ == 1
>-using std::assoc_laguerref

This doesn't look like the right patch, because these lines aren't in
the version on trunk.