[PATCH xserver 1/1] list: Use offsetof() to determine member offsets within a structure

Jeremy Huddleston Sequoia jeremyhu at apple.com
Wed Aug 29 14:09:32 PDT 2012

On Aug 29, 2012, at 2:00 PM, Jeremy Huddleston Sequoia <jeremyhu at apple.com> wrote:

> On Aug 29, 2012, at 12:28 PM, Mark Kettenis <mark.kettenis at xs4all.nl> wrote:
>> Jeremy, did clang actually complain about __container_of() as well, or
>> was the change to that function just an optimization?
> It doesn't complain (no warning, no error).  If run with -O1 or higher, it just produces code which results in a segfault when the server launches.  __container_of is the cause of the segfault because __container_of is used by xorg_list_for_each_entry.

Actually, I take that back.  It does print a -Wuninitialized warning, but it's not really clear the implications of that because I think anyone reasonable would look at that and say "well I don't care that it's uninitialized because we don't need the actual value, just the delta" …


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