[Fixed] mysterious "Invalid statement" Zscript errors

[JPL]

A mod I released last year has started failing on startup in recent-ish versions of GZDoom. 4 errors that all say "Invalid statement", two of them on the same line. A couple of the lines in question are simple function overrides, eg

Code: Select all • Expand view

override void PostBeginPlay()

, and no further information is given so it's pretty unclear what the real problem is or how to fix it.

You can download the latest released version of the mod here: https://jp.itch.io/mr-friendly

[_mental_]

It's caused by no-op expressions, like

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if (const_evaluated_to_false) // ...

I think this should be fixed like this.

[Graf Zahl]

Wouldn't it be better to give FxNop a non-error type instead?

[_mental_]

Probably, yes. Actually, I thought TypeError was used to catch errors like this.

[Graf Zahl]

Errors, yes, but this should at most be a warning.

[_mental_]

It's a code generation error because construct with a constant condition is valid.

TypeVoid for FxNop fixes the issue as well. Should we prefer this solution over my PR?

[Graf Zahl]

It's a code generation error because construct with a constant condition is valid.

Yes, but that means that FxNop may not have an error type. FxNop is meant as a valid stand-in for an empty statement where null is not viable.

[_mental_]

Fixed in 78c0b7f.