Grand Theft Aero partial skip explanation

Nov 10 12:44:38 <Powdinet>	Start Uzi Rider and drive to Grand Theft Aero, start GTA
Nov 10 12:44:47 <Powdinet>	after a few seconds the game says to go up the lift
Nov 10 12:44:52 <Powdinet>	this is a partial skip
Nov 10 12:45:04 <Powdinet>	however I looked at the code and I don't understand why it works
Nov 10 12:49:51 <Nick007J>	oh, this might be interesting
Nov 10 12:50:09 <Nick007J>	they actually used a while loop in a subroutine
Nov 10 12:51:47 <Nick007J>	however, the offset is ~5025, and it corresponds to a "Take the lift up the tower!" loop
Nov 10 12:53:40 <Nick007J>	does the mission even finish correctly?
Nov 10 12:53:52 <Powdinet>	the mission passes
Nov 10 12:53:58 <Powdinet>	and apparently another fails
Nov 10 12:54:09 <Powdinet>	but the game still crashes/softlocks upon starting another mission
Nov 10 12:54:42 <Nick007J>	most likely because it passed but didn't finish
Nov 10 12:54:52 <Nick007J>	I still would take a look on that
Nov 10 12:55:03 <Powdinet>	https://dl.dropboxusercontent.com/u/48219719/GTA3sf2.b
Nov 10 12:55:07 <Nick007J>	ty
Nov 10 12:55:49 <Powdinet>	How does it go to offset 5025~though? isn't it supposed to stay at the wait in YARD2_2577 until you go into Hepburn Heights?
Nov 10 12:56:07 <Powdinet>	ooh
Nov 10 12:56:15 <Powdinet>	00D6: if
Nov 10 12:56:15 <Powdinet>	80DC:   not is_player_in_car $PLAYER_CHAR car $GANG_CAR_YD2
Nov 10 12:56:22 <Powdinet>	it gosubs here
Nov 10 12:56:24 <Powdinet>	I see
Nov 10 12:56:50 <Powdinet>	okay that makes sense
Nov 10 13:04:20 <Nick007J>	well, mission finised alright
Nov 10 13:04:40 <Nick007J>	I was wrong since it forces script termination no matter if stack is not empty
Nov 10 13:06:39 <Nick007J>	but original GTA haven't finished for some reason
Nov 10 13:06:48 <Nick007J>	even though I've seen "plane was destroyed"
Nov 10 13:16:16 <Nick007J>	I understand why second GTA instance hasn't failed, it only creates a plane after player get to Shoreside
Nov 10 13:16:33 <Nick007J>	I just can't understand what caused "mission failed" and what even failed
Nov 10 13:18:02 <Nick007J>	ooh, I got it
Nov 10 13:18:41 <Nick007J>	the first instance has been passed and failed simultaneously becuase of the gosub from Uzi Rider
Nov 10 13:19:47 <Powdinet>	'wat'
Nov 10 13:19:52 <Nick007J>	it has been passed, it tried to return to try to get to cleanup, but instead of cleanup jumped into a middle of self
Nov 10 13:20:18 <Nick007J>	found out that plane doesn't exist, jumped to mission failed and only then return to a proper cleanup
Nov 10 13:20:52 <Nick007J>	meanwhile second copy is still running
Nov 10 13:24:46 <Nick007J>	I mean the call stack is: ~25, ~2500, ~5025, the last one is running, gets to "mission_passed", then executes return
Nov 10 13:25:02 <Nick007J>	it is supposed to go to ~25 to make cleanup, but gets to ~2500 instead
Nov 10 13:25:40 <Nick007J>	it finds out the plane was never created, which equals to being destroyed, jumps to "mission_failed" and it executes return
Nov 10 13:25:52 <Nick007J>	this time to a correct place and mission finishes
Nov 10 13:27:34 <Powdinet>	this would only leave the extra instance running normally then, right?
Nov 10 13:27:51 <Nick007J>	yes, unfortunately vigilante crashes it though
Nov 10 13:28:43 <Nick007J>	interestingly enough, if you returned to Donald after you entered Shoreside, and completed the mission normally, it would have completed mission 3 times