re PR middle-end/36282 (Spurious warning "asm declaration ignored due to conflict with previous rename")

	PR middle-end/36282
	* c-pragma.c (apply_pragma_weak): Only look at
	TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl)) if
	DECL_ASSEMBLER_NAME_SET_P (decl).
	(maybe_apply_pending_pragma_weaks): Exit early if
	vec_safe_is_empty (pending_weaks) rather than only when
	!pending_weaks.
	(maybe_apply_pragma_weak): Likewise.  If !DECL_ASSEMBLER_NAME_SET_P,
	set assembler name back to NULL afterwards.

	* c-c++-common/pr36282-1.c: New test.
	* c-c++-common/pr36282-2.c: New test.
	* c-c++-common/pr36282-3.c: New test.
	* c-c++-common/pr36282-4.c: New test.

From-SVN: r208557