PR c/25559

	* c-common.c (handle_vector_size_attribute): Reject zero vector size
	as well as sizes not multiple of component size.

	* gcc.dg/pr25559.c: New test.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@109316 138bc75d-0d04-0410-961f-82ee72b054a4