GZDoom 3.6.0 fatal crash ()

[Dinosaur_Nerd]

When creating a ZScript monster, setting a frame like this

Code: Select all

Pain:
        FATT J 4 ();                                // This frame causes GZDoom to crash
        FATT J 4 A_Pain();
        Goto See;

Causes GZDoom to crash with a very fatal error code : C0000005

I had to track down the problem manually and correct it.
I understand that this is a newbie mistake, however, I wasn't expecting GZDoom to crash to an error code and not give me a hint about what went wrong.

A test wad is available here: Broken Fatty

[Player701]

Well, GZDoom does give an error message just before crashing, at least in the latest devbuild git version (g3.7pre-771-g4a83f4d25): "Invalid function identifier".

The problem is that the FxNop object that is created when this error message is produced doesn't have a ValueType set, and the code generator then tries to get an integer constant from it. The code in FxIntCast::Resolve is not prepared to handle situations when ValueType of the base expression is null, so it makes GZDoom crash. FxNop should probably have its ValueType set to something meaningful, shouldn't it?