[v3, 4.9] Handle C++11 <math.h> overloads on Solaris 11, 12

[Jonathan Wakely]

On 22/02/16 16:38 +0100, Rainer Orth wrote:
>With the latest Solaris 11.3 SRU, the C++11 <math.h> overloads have been
>backported to Solaris 11.3.  While mainline and the gcc-5 branch already
>cope with this due to
>
>	https://gcc.gnu.org/ml/gcc-patches/2015-11/msg02075.html
>
>this broke Solaris 11 bootstrap on the 4.9 branch.  Therefore I'd like
>to backport the patch to the 4.9 branch, too.  The version applied to
>the gcc-5 branch required a minimal change to the testcase only.
>
>Bootstrapped on i386-pc-solaris2.11, ok for 4.9 branch?

I'm happy with this if the release managers are too.