re PR tree-optimization/26854 (Inordinate compile times on large routines)

re PR tree-optimization/26854 (Inordinate compile times on large routines)

	PR tree-optimization/26854
	* c-decl.c (struct c_scope): Add field has_jump_unsafe_decl.
	(decl_jump_unsafe): Move higher in file, with no other change.
	(bind): Set has_jump_unsafe_decl if appropriate.
	(update_label_decls): Test has_jump_unsafe_decl to avoid loop.
	(check_earlier_gotos): Likewise.
	(c_check_switch_jump_warnings): Likewise.

From-SVN: r169267