You are right. This code runs just fine on both of these online Lua websites.
local tab = {}
tab[938388893] = "hi"
tab[987383332] = "Hello"
for k,v in pairs(tab) do print(k) print (v) end
https://www.lua.org/cgi-bin/demo https://luajit.me/
But when I try it using the Sol library (embedded in C++) it eats all my memory. Is it a Sol issue or a C Lua binding issue? Anybody know?