How do I report bugs on snapshots from the CVS?
X.Org appreciates that you are testing snapshots from CVS. The more testing the snapshots get the more stable the final release will be. When you are using snapshots you have probably compiled them yourself.
If you know that the problem did not appear in the last release or an earlier snapshot you should try to find out in which snapshot version the problem was introduced. To do so try to estimate where the problem may occur and check the CHANGELOG at
/xc/ChangeLog
for a change in that area. If this appears to be too difficult you may go back thru the tagged CVS versions until you find one that works. You don't have to revert the entire build tree to an older version. In most cases it is sufficient to revert everything below xc/programs/Xserver.
In case the Xserver segfaults the log file is not very helpful to obtain information where the segfault happened. You should use a debugger to produce a backtrace. Also you should build the code with debugging symbols enabled. Helpful hints on debugging can be found at DebuggingTheXserver.