Unstable mesa buildings

[alexandre schenberg]

Hello. I have two different mesa versions (7.5.2 and 13.0.0) built by myself with the purpose of linking it against a few applications.
I built one of them (snes9x) and tested it. At first it seemed ok, but soon the problems became clear. When I send a character to move to a certain direction, it usually behaves as expected, but it suddenly can become "locked", like the character persistently ignoring my subsequent commands. After a decent amount of time, it start to behave as expected once more.

This is happening with both Mesas, that were built against a fairly different set of Xorg libraries (2-3 are the same).
I am fairly sure that Mesa is the culprit, because if I omit it of the list of libraries to link against, it will behave ok.

So my question is: How can I debug this kind of problem and figure out what is happening?