T2: fine in 32-bit, Lua error in 64-bit

[Therem Harth]

I've noticed that (in ToME 2.3.5) hitting escape in the Geomancy spell menu produces a Lua error on 64-bit Linux. The error indicates that the game attempted to index a nil variable in the function get_affect() in lib/core/s_aux.lua. It's not fatal, but it is quite unsightly.

What's weird is that the 32-bit Linux version is perfectly okay.

(2.3.9-ah also doesn't have this issue.)

Anyone know why an error like this might occur only in 64-bit mode?

[AnonymousHero]

It may be that a function prototype/declaration in the *.pkg file differs from the declaration in the *.h file.

[Therem Harth]

Thanks...

Looking at the stack traceback, BTW, it looks to me like cast_school_spell() is being invoked even when you hit the escape key - and thus invoked on a spell that doesn't exist, producing the error. Not sure why; escape is supposed to produce a value of -1, which should be caught by an if statement and cause cast_school_spell not to be invoked:

		s = get_school_spell("cast", "is_ok_spell", 63)
		if (s ~= -1) then
			cast_school_spell(s, spell(s))
		end

Maybe there is some kind of type mismatch on 64-bit, that's preventing the value from being properly recognized?

[AnonymousHero]

It's probably a declaration mismatch on the return of the function then. -1 in two-completement in 32-bit has a tendency to not stay -1 when "converted" (without sign extension, or a random adjacent garbage)

[Therem Harth]

Looks like you're right, it's a u32b getting converted to an int. Thank you.

Edit: wait, u32b? How are we supposed to get -1 with an unsigned integer?

Edit 2: yes, making get_school_spell return an int instead of a u32b worked. Hurray.