Problem:
Build is not reproducible, because generated source files (.c/.h/) are not
deterministic, mostly because Lua pairs() is unordered by design (for security).
https://github.com/LuaJIT/LuaJIT/issues/626#issuecomment-707005671https://www.lua.org/manual/5.1/manual.html#pdf-next
> The order in which the indices are enumerated is not specified [...]
>
>> The hardening of the VM deliberately randomizes string hashes. This in
>> turn randomizes the iteration order of tables with string keys.
Solution:
- Update the code generation scripts to be deterministic.
- That is only a partial solution: the exported function
(funcs_metadata.generated.h) and ui event
(ui_events_metadata.generated.h) metadata have some mpack'ed
tables, which are not serialized deterministically.
- As a workaround, introduce `PRG_GEN_LUA` cmake setting, so you can
inject a modified build of luajit (with LUAJIT_SECURITY_PRN=0)
that preserves table order.
- Longer-term we should change the mpack'ed data structure so it no
longer uses tables keyed by strings.
Closes#20124
Co-Authored-By: dundargoc <gocdundar@gmail.com>
Co-Authored-By: Arnout Engelen <arnout@bzzt.net>
cb757f2663