Re: [Qemu-devel] [PATCH RESEND 1/3] usb-ccid: make ccid_write_data_block() cope with null buffers

[Gerd Hoffmann]

On Do, 2017-03-23 at 13:41 +0100, Markus Armbruster wrote:
> Gerd Hoffmann <address@hidden> writes:
> 
> >   Hi,
> >
> >>  oops, there are hard-coded calls with NULL/0. I suppose to fix clang
> >> warning, it would need to check if data != null for memcpy.
> >
> > I'd check for len > 0, and in that if branch we can also assert on data
> > == NULL and thereby check that len and data are consistent.
> 
> If len is non-zero but data is null, memcpy() will crash just fine by
> itself, so why bother asserting.

To make clang happy?  But maybe clang is clever enough to figure data
can't be null at that point in case we call memcpy with len != 0
only ...

cheers,
  Gerd