Use explicit locations for some warnings in c-pragma.c.

Use explicit locations for some warnings in c-pragma.c.

gcc/cp/ChangeLog:

2015-09-18  Manuel López-Ibáñez  <manu@gcc.gnu.org>

	* parser.c (pragma_lex): Add loc argument. Rearrange the code to
	make it more similar to the C version.

gcc/c-family/ChangeLog:

2015-09-18  Manuel López-Ibáñez  <manu@gcc.gnu.org>

	* c-pragma.c (handle_pragma_diagnostic): Use explicit location
	when warning.
	* c-pragma.h (pragma_lex): Add optional loc argument.

gcc/c/ChangeLog:

2015-09-18  Manuel López-Ibáñez  <manu@gcc.gnu.org>

	* c-parser.c (pragma_lex): Add loc argument.

gcc/testsuite/ChangeLog:

2015-09-18  Manuel López-Ibáñez  <manu@gcc.gnu.org>

	* gcc.dg/pragma-diag-5.c: New test.

From-SVN: r227923