Re: strange error while debugging

[roberto@... (Roberto Ierusalimschy)]

> I assume the real cause is an error in the use of lua in the luatex
> program, but I do not have the faintest clue what is going on here,
> so I hope someone can explain to me in what direction to look. Under
> what conditions would this 'ci->savedpc' possibly be NULL?

savedpc is always NULL for C functions. But the previous check
(if (!isLua(ci))...) should return in that case. Otherwise it is NULL
just when the function in being called. But it is initialized before
'ci' is incremented to point to it (see luaD_precall).

Did you use valgrind or something similar (mainly to check whether
savedpc is actually NULL or an uninitialized value that happens to
be NULL)?

-- Roberto