Re: Upgrading Lua 5.4.2 to 5.4.3+ in a C++ project leads to PANIC

[Aleksandr Zenkov <webmaster@...>]

Thank you for your reply!

You are right about this, I did a proper research and found alot of 
interesting bugs in this code. To begin with, _TRACEBACK on top stuff 
was dropped already in early Lua 5.0. Few wrong calls to multiple API 
functions which completely broke the Lua stack. I wonder how this code 
could actually work all this time until Lua 5.4.3. With other words 
there were made changes to Lua to protect itself even better, which is 
just great! However, I corrected all the errors and made a proper 
cleanup in my code, everything seems to work smooth now. Thank you 
everyone for great help!

Regards.

On 2022-12-06 00:07, Patrick Kurth wrote:
> This function is a bit weird. You emtpy the stack and then get the
> number of stack items (line 262, into 'base'), which will always be 0.
> Then you push "_TRACEBACK" and the global table, only to (I guess
> that's what you want to do) reverse the order of those two.
> First of all you call lua_insert with index 0, which is not valid.
> Secondly, why use lua_insert at all when you can just push the stuff
> you need in the right order?
> Anyway, I'd start with checking the indices, maybe I'm missing
> something here, but this caught my attention.
>
> Kind regards,
> Patrick