06464: Every system with softlists using the "requirement" sharedfeat: Software list items with the "requirement" sharedfeat don't work

ID	Category [?]	Severity [?]	Reproducibility	Date Submitted	Last Update
06464	Interface	Minor	Always	Jan 1, 2017, 14:13	Feb 19, 2017, 00:54

Tester	r09	View Status	Public	Platform	MAME (Official Binary)
Assigned To	Bletch	Resolution	Fixed	OS	Windows 10 (64-bit)
Status [?]	Resolved			Driver
Version	0.181	Fixed in Version	0.184	Build	64-bit
		Fixed in Git Commit		Github Pull Request #

Summary	06464: Every system with softlists using the " requirement" sharedfeat: Software list items with the "requirement" sharedfeat don't work
Description	Running MAME with a software list item that includes the "requirement" sharedfeat can fail in two different ways: - The required additional SL item specified in the sharedfeat tag isn't automatically mounted. This differs from older versions of MAME where it was auto-mounted. - MAME crashes with the following error: "Fatal error: Illegal operation on unmounted image".
Steps To Reproduce	For the first case: run "mame c64 cmk49" and the Music 64 cartridge won't be automatically mounted along with the cassette. For the second case: run "mame x1 pinball" and MAME will crash. These are just two examples, this behavior can be reproduced with any SL item that includes an additional requirement.
Additional Information	0.176 seems to be the last version where auto-mounting of requirements worked.
Github Commit

Flags
Regression Version	0.177
Affected Sets / Systems	Every system with softlists using the "requirement" sharedfeat

Attached Files

No.13535 AJR Developer Jan 11, 2017, 18:36	An important point here that many image devices are also slot devices, and the frontend has to repeatedly jump through hoops to make sure both get loaded when softlists are used. The problem was likely aggravated in the case of "mame x1 pinball" because that finds the cassette version, and the X1 cassette tape is not a slot device, whereas the floppy disk that it requires has to have a slot of its own. The same situation happens with PCE/TG16 CD-ROMs, which I could verify didn't work because the frontend wasn't even looking at the CD-ROM softlist to see if the software required a card that required a slot, and it was too late to slot the card by the time it was actually loaded. I've opened a pull request that fixes at least this case.
No.13538 AJR Developer Jan 15, 2017, 03:51	r09, can you confirm that commit 17af0f9c661e0855607703faf66c1e807e888d82 has fixed this problem for you?
No.13543 r09 Tester Jan 19, 2017, 17:43	Confirmed, it works perfectly now. :)
No.13651 cuavas Administrator Feb 19, 2017, 00:54	The "fix" was just too nasty.