Core bug report

[Legend]

In Mario Party 2, when you unlock and try to start "Dungeun Duos", it shuts off the video plugin with a gfx exception. This is what Gonetz had to say:

"This crash in dangeon dash minigame is caused by a bug in emulator's core. Jabo's plugin also crashes at this place."

 

[Gonetz]

Technical details:
The crash is caused by following sequence of commands:

0017dee8 (c0:db060004, c1:ffffffff): uc2:moveword SEGMENT ffffffff -> seg1
......
......
......
0029b118 (c0:01004008, c1:01000000): uc2:vertex n: 4, v0: 0, from: 007fffff

As you can see, moveword command set wrong value for SEGMENT 1
Previous value for this segment was
0017dea0 (c0:db060004, c1:0029af70): uc2:moveword SEGMENT 0029af70 -> seg1

BTW, Project64 generates the same dlist, so it's not 1964 specific bug.

 

[Rice]

As I remember, this game is not the only one to set segment to 0xFFFFFFFF. A plugin probably need to check the value before assigning it to segment register.