Bug Reports?

Discussion of developmental aspects of the MiSTer Project.
deepthaw
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Bug Reports?

Unread post by deepthaw »

Is GitHub the best place to submit bug reports we find with particular games with particular cores?

Also: Are there any given steps we should take to make sure it's not a weird bug on our end before reporting it?
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Chris23235
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Re: Bug Reports?

Unread post by Chris23235 »

Github is the best place, because it's easy to check for developers and it's easy for you to see, if an issue is already posted. You should write a detailed bug report and write what you encountered and what you have already tried to see if it is on your end. By writing it up you will most certainly see, if there are things you can try first. At least that's my experience. I often wrote bug reports that I didn't sent, because while writing I got an idea what to try.
dshadoff
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Re: Bug Reports?

Unread post by dshadoff »

If you do file a bug report in GitHub, please be sure that:

1) it does not exist on original hardware. YouTube videos don't count, as there are too many emulation videos which aren't accurate

2) you provide which version (release date) of the core that you saw it on. Ideally, try older versions of the core too, to identify when the behaviour first started.

3) It needs to be reproducible. A good description of what you notice is very important. If you can, record a video and identify the moment at which it occurs. If possible, A/B recordings between original hardware and MiSTer core for comparison. If it's difficult to get to the point where the issue happens, you'll need to help us out by supplying a way to get to that point of the game - savegames, level-select keypress sequences, etc.

4) Don't submit a report about a hack of a game, as too many of those were not playable on original hardware. Submit if it happens on the original (published version) of the same game.

5) Check to see whether it has been submitted already. No duplicates please. Also, GitHub issues are not a place to say "me too". However, adding more information to clarify specifics around the issues is welcome.

-> If you're not sure whether an issue exists on original hardware/software, discuss it in the forum first.
ExCyber
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Re: Bug Reports?

Unread post by ExCyber »

In addition to dshadoff's suggestions:
  • Post the MD5 or SHA-1 hash of the ROM/disk image after verifying it on the MiSTer platform to confirm that you're actually running a known image. Multiple people have reported strange behavior only to find that they'd somehow corrupted their files (e.g. by FTPing binary files in ASCII mode).
  • Make sure it's not a PAL/NTSC issue (e.g. running NTSC verison of a game on a PAL hardware configuration). This doesn't just affect frame rate; it can also cause strange bugs. On some systems, games can detect the video standard and arbitrarily alter their behavior as well.
  • Search to see if the bug has been found on emulators. MAME Testers is a great resource for arcade games. This is also useful for figuring out whether your bug is actually a bug in the game itself (the MAME jargon for this is "BTNAB"), but these discussions often get into what actually needs to be fixed, even when the conclusion is that it won't be fixed in the emulator.
  • If the game has or had an active competitive player base (e.g. fighting games, speedrunning, high score competitions), see if the bug is mentioned by players in forum posts or articles about the game. Players may have already determined whether the bug is e.g. in a specific revision of the game and whether it occurs on real hardware.
deepthaw
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Re: Bug Reports?

Unread post by deepthaw »

Thanks for all the tips - will do. (The games are Tengen's Gauntlet for NES and Super Turrican for NES. I'll dive into the ROM versions, and more testing before I submit them - they're basically "all messed up." but other ROMs from the same no-intro set all work fine.)
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