PR target/28648 c:

	* tree.c (handle_dll_attribute): Return early if not a
   	var or function decl.

testsuite
	* gcc.dg/attr-invalid.c: Add tests for invalid dllimport.



git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@116270 138bc75d-0d04-0410-961f-82ee72b054a4