re PR go/49889 (Calling a function whose name is obscured by a local variable does not produce an error)

	PR middle-end/49889
gcc	* varasm.c (merge_weak): Generate an error if an attempt is made
	to convert a non-weak static function into a weak, public function.

testsuite	* gcc.dg/pr49889.c: New test.

From-SVN: r235484