re PR c++/25294 (Bogus "unterminated comment" error from #pragma comment)

	PR c++/25294
	* directives.c (do_pragma): If pragma line ends with multi-line
	block comment, end the saved deferred pragma string before that
	comment.  Handle embedded '\0' chars on the pragma line.

	* gcc.dg/pragma-pack-3.c: New test.
	* g++.dg/parse/pragma3.C: New test.

From-SVN: r109201