[CMake] Checking function or symbol in namespace

[Jed Brown]

On Thu, 21 Jan 2010 16:55:20 +0000, Mateusz Loskot <mateusz at loskot.net> wrote:
> Yes, though I'd annoyingly keep my side that CXX variants of the macros
> would be useful and make C vs C++ separation more clear to user.

The problem is that the interface for the C++ variant *cannot* look like
check_function_exists, because the C++ language doesn't enable it.  It's
better *not* to have a variant with a similar name and completely
different interface.  So use check_cxx_source_compiles for C++.

Jed