Please have a look at the crash that I reported there:
It has a back-trace pointing to _mesa_DeleteTextures, and inside of it, in _mesa_HashLookup_unlocked.
It is looking like a linked list is expected to be null-terminated, and it crashes when some bogus node pointer is 0x100000001.
I tried calling glIsTexture before, just to check, and as a result, got exactly the same crash in glIsTexture.
From the other bug report, it looks like this was a bug in the app code. I'm closing this bug.