re PR c++/32121 (C++ front-end accepts invalid __label__ declarations)

re PR c++/32121 (C++ front-end accepts invalid __label__ declarations)

	PR c++/32121
	* parser.c (cp_parser_compound_statement): Handle label-declarations
	at the beginning of the compound statement.
	(cp_parser_block_declaration): Issue diagnostics about __label__
	not at the beginning of a block.

	* g++.dg/ext/label4.C: Adjust error regexp.
	* g++.dg/ext/label6.C: Adjust error regexp.
	* g++.dg/ext/label7.C: New test.
	* g++.dg/ext/label8.C: New test.
	* g++.dg/ext/label9.C: New test.

From-SVN: r129253