Making lua execution results reproducible across architectures

[hollyrosella@...]

I would like to make a version of lua with perfectly reproducible results on all machines which run it.  I think the main difficulty is reproducibility of floating-point calculations, but if there are other possible snags, I would be happy to learn of them.  My plan is to replace the arithmetic macros in luaconf.h and the function calls lmathlib.c with calls to the relevant functions in the MPFR library, which should make atomic floating-point operations reproducible.  I am also concerned about ensuring reproducible order of execution.  If I compile with gcc using -O0, will that suffice?

Holly