08768: sf2049 sf2049se nbagold: CHD ERROR: Decompression error

ID	Category [?]	Severity [?]	Reproducibility	Date Submitted	Last Update
08768	Crash/Freeze	Major	Always	Sep 23, 2023, 09:22	Sep 27, 2023, 09:13

Tester	Kaylee	View Status	Public	Platform	MAME (Self-compiled)
Assigned To	AJR	Resolution	Fixed	OS	Linux (64-bit)
Status [?]	Resolved			Driver	midway/vegas.cpp
Version	N/A	Fixed in Version	N/A	Build	64-bit
		Fixed in Git Commit	0c9d465	Github Pull Request #

Summary	08768: sf2049 sf2049se nbagold: CHD ERROR: Decompression error
Description	When I ran sf2049se this morning it came up with the error: "sf2049se.chd CHD ERROR: Decompression error" happens with a self-build mame0258-254-g9ea90a73297. Also happens with sf2049 and nbagold if I use a previous build (mame0258-40-g8fbfd4936c5) it works
Steps To Reproduce
Additional Information
Github Commit

Flags
Regression Version
Affected Sets / Systems	sf2049 sf2049se nbagold

Attached Files

No.21766 Tafoid Administrator Sep 23, 2023, 09:35	Have you tried deleting the "diff/sf2049.dif" file and trying again? Same with any other CHD game having issues?
No.21767 Robbbert Senior Tester Sep 23, 2023, 10:09	Tried sf2049 and sf2049se - no problem with latest git. However nbagold exhibited the problem nbabfl3.chd CHD ERROR: Decompression error Fatal error: Required files are missing, the machine cannot be run. I deleted all config/ini files for this game and there's no diff file, but no difference.
No.21768 Tafoid Administrator Sep 23, 2023, 10:09 edited on: Sep 23, 2023, 10:18	Some research seems to suggest something was changed with regards to CHD which makes certain .dif files no longer work correctly. Traced to September 17/18 and, quite possibly, this commit: https://github.com/mamedev/mame/commit/94ff3857e275aa3d6181d643986f0df813d00c63 This may or may not be unavoidable where new .dif files need to be made because of the changes. EDIT: I can confirm that NBAGOLD does show that error for me as well without producing a .dif
No.21769 Robbbert Senior Tester Sep 23, 2023, 10:20	Tested a few more games and the problem is widespread. For example step3, neomania and carnevil.
No.21770 Kaylee Tester Sep 23, 2023, 10:28	I've deleted the whole .mame folder and gives the same error.
No.21777 PepsiBoy428 Tester Sep 24, 2023, 01:09	I wonder, does this problem happen with Rush The Rock? (sfrushrk)
No.21778 Robbbert Senior Tester Sep 24, 2023, 02:14	Yes, it does. I'm guessing about half of CHD-based games have regressed,
No.21781 Tafoid Administrator Sep 27, 2023, 09:12	This bug does not fit into MT's scheme of version to version bug reporting. I've taken out the versions and it still references the original breaking/bugfix commits should it be needed.