[Xcb] Question about XML spec, and QueryExtension

Barton C Massey bart at cs.pdx.edu
Tue Aug 26 23:04:32 PDT 2008

In message <48B2BC85.50304 at hummingbird.com> you wrote:
> Antoine Latter wrote:
> > The XCB xproto.h doesn't include the padding either - and it's used
> > extensively in xcb_ext.c, which makes me think that if QueryExtension
> > were broken extensions in general would be broken.
> > 
> > Am I missing something here?  Presumably extensions work in XCB.
> There is a bug in the XML (missing padding), but the C compiler
> fortuitously papers-over the bug by automatically aligning the
> structure. Not all C compilers do this, so the bug needs to be fixed
> regardless.

I thought it might be something like that.  THanks for the diagnosis!

I agree that the patch should be inserted here. I'd do it right now, but I'm 
on an eeePC on a weak link in a foreign country. Anyone?

> It would be interesting to compile all of XCB with -Wpadded to see what 
> other bugs there are in the XML definitions.  

Indeed.  Someone want to try this?  I suppose I'll get to it eventually
if no one else does, but it may be a long while.  I think it just amounts
to some kind of compile with and without followed by a diff?

> (See also:
> http://lists.freedesktop.org/archives/xcb/2008-January/003186.html -
> which hasn't been applied yet).

Sigh.  Our apologies.

Peter, we would love it if you would please apply for commit privileges
so you can apply this patch yourself. :-)  Also make sure it's in
Bugzilla, if you would be so kind, even if you fix it right away.

And again, thanks hugely for your attention to this stuff.


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