XFree86 seems to be setting the count member of expose events to zero, even when
more expose events follow. I am using the shared memory extension and multiple
threads in my application. XFree86 was installed on my system using the Ubuntu
Linux package 4.3.0.dfsg.1-6ubuntu25.
Same problem seems to apply to the Xorg tree... the question is who may be
familar enougth with the "Expose"-event generation to help (I would expect the
block handler would do some optimisation but it I don't see any code in that
path... ;-( ).
Sorry about the phenomenal bug spam, guys. Adding xorg-team@ to the QA contact so bugs don't get lost in future.
This really needs a testcase to be investigated further.