The patch tests that the C and C++ compilers actually exist
and work. autoconf seems to default to 'g++' when C++ compiler is not
found, which causes the following error (when the compiler isn't
there):

checking for uuid_generate in -luuid... no
configure: error: cannot link with -luuid, install uuid-dev.

The config.log contains the real error message "g++ command not found"
but the error message shown to the user is misleading.
Signed-off-by: Mikko Koppanen <mkoppanen@php.net>