Andrew Morton wrote:

hm.  So if I have

	struct bar {
		unsigned long b;
	} __attribute__((packed));

	struct foo {
		unsigned long u;
		struct bar b;
	};

then the compiler can see that foo.b.b is well-aligned, regardless of the
packedness.

In Ralf's code, the structure is anonymous, and is used to declare a
pointer type, which is initialized from a void *.  So I think the
compiler isn't allowed to assume anything about its alignment.

    J