06361: Cartrdige memory accessed directly with cheats will crash MAME

ID	Category [?]	Severity [?]	Reproducibility	Date Submitted	Last Update
06361	Cheat System	Critical (emulator)	Always	Sep 2, 2016, 05:31	Mar 2, 2017, 12:38

Tester	msutton	View Status	Public	Platform	MESS (Official Binary)
Assigned To	Pugsy	Resolution	Fixed	OS	Windows 10 (64-bit)
Status [?]	Resolved			Driver
Version	0.177	Fixed in Version	0.184	Build	64-bit
		Fixed in Git Commit		Github Pull Request #

Summary	06361: Cartrdige memory accessed directly with cheats will crash MAME
Description	When running a NES game with cheats enabled mame crashes with no errors. I am using the latest Pugsy's Cheats. Looking at the cheat files, the cheats want to modify nes_slot:cart:prg_rom It looks like this region is not loaded before the cheat file is loaded. I know this is not a solution but points to possibly where the error is occurring. This affects not only NES, but all cheat that reference cart memory directly.
Steps To Reproduce	mame64 nes -cart1 smb1 -cheat -v
Additional Information
Github Commit

Flags
Regression Version
Affected Sets / Systems

Attached Files	output-crash.txt (3,278 bytes) Sep 2, 2016, 05:31 Uploaded by msutton Output when crashes [Show Content]
Attached Files	output-working.txt (5,441 bytes) Sep 2, 2016, 05:32 Uploaded by msutton output after modifying the source code [Show Content]

No.13096 Tafoid Administrator Sep 2, 2016, 11:35	For now, you can use the built in cheat plugin -plugins -plugin cheat to avoid this issue.
No.13099 msutton Tester Sep 2, 2016, 18:41	I tried the suggestion to use the cheat plugin. When I use the cheat plugin I do not get a list of cheats in game to chose from under the plugin menu. I get a message that says,"This non-arcade system has been added during the amalgamation of MESS into MAME. If there is a softwarelist with games in, then cheats may well appear when you load the game." I am getting console output that it is finding the cheat.7z file and sending it to cache. Maybe I do not have something configured correctly.
No.13101 Tafoid Administrator Sep 2, 2016, 19:29	It loads NES cheats for me in my testing with latest official 0.177 as well as current GIT sources + cheat.7z from Pugsy's mame nes smb1 -plugins -plugin cheat You mentioned you modified your source locally? Perhaps you are using that?
No.13102 msutton Tester Sep 2, 2016, 20:51 edited on: Sep 2, 2016, 20:52	I see I was using mame64 nes -cart1 smb1 -plugins -plugin cheat to make it work I needed to add the software title by itself, software title as parameter of -cart1 is not enough mame64 nes smb1 -cart1 smb1 -plugins -plugin cheat now it is working as expected, thanks for your help.
No.13676 Tafoid Administrator Mar 2, 2017, 12:35	Crashes were fixed with 06477 The nes (and other cheats which adjusted cart memory directly) were still showing up invalid memory name. This was fixed with this pull request/commit in which the startup order of initialization was adjusted so that memory names were not 'forgotten' https://github.com/mamedev/mame/pull/2088