When playing gradius rebirth with the "unlimited use of konami code" gecko cheat enabled will cause dolphin to crash when you die. I can post the full log if you want, but this is where the crash occurs:
56:09:314 PowerPC\PPCAnalyst.cpp:781 E[JIT]: Instruction hex was 0!
56:09:314 HW\MMIO.cpp:198 E[MI]: Trying to read32 from an invalid MMIO (addr=ffff8368)
56:09:314 PowerPC\PPCAnalyst.cpp:781 E[JIT]: Instruction hex was 0!
Unfortunately, that's what happens sometimes when using cheats. The cheats are designed to do things on real hardware that Dolphin doesn't do (or doesn't do quite accurately), so getting cheats to work is hit or miss in some cases.
If it worked before in a previous revision, then it's definitely a bug and you should report it as such. If it never worked in Dolphin though, there's not much you can do aside from trying to make your own Dolphin compatible cheats.
Well, this is the first time I've tried using the cheat system so I don't know if it worked in previous versions, however in the notes for the code it says "works for version 1.2" and right now I'm using the latest version that was uploaded today
Is this a code you found yourself or did you have Dolphin pull it (Download codes from WiiRD database)? It probably isn't a reference to Dolphin (might be talking about something on the Wii, Gekko OS maybe?). I don't think Dolphin ever had a 1.2 release.
If it worked in something like 4.0.2 but not in the latest revision, then it's a regression. Try 4.0.2 and see if that works. If not, again, it's because emulating cheats can be hit or miss.
1.2 refers to revision 3 of a game disc usually.
I had dolphin download the code from the wiird database. tried it with both the x86 and x64 versions of 4.0 and 4.0.2, same behaviour. The other 3 cheats that were downloaded from the database seem to work fine, it's just that one the makes it crash.
It's probably the case that it never worked in Dolphin then. There's not much you can do at this point.