Luac 5.4.0 beta (oct 2019) crashes when using vararg unpacking in luac -p -l -l

[Bas Groothedde <lua@...>]

Hi there!

I'm creating a godbolt.org like service for Lua, and during my development I noticed that Luac 5.4.0 Beta (Oct 2019) does not 
like the vararg operator enclosed in a new table. 

I'm not sure if this is changed behaviour in 5.4 or if it has already been reported, however it causes a segmentation fault when 
listing the instructions of a previously dumped chunk and that didn't seem like desired.

code:

local function lua540_beta_oct_2019_vararg(...)
  local asTable = {...}; -- causes luac -p -l -l to crash
  return asTable;
end

reproduce:

1. Dump this code using luac; luac -o crash.luac crash.lua
2. List the instructions using luac; luac -p -l -l crash.luac

OS:

• Windows 10 Professional, Lua 5.4 x64 bit build MSVC
• Ubuntu 18.04 LTS, gcc 8 x64 and x86 builds

Thank you.

---

Bas Groothedde
Imagine Programming