nodemcu-firmware/app/lua/legc.c

// Lua EGC (Emergeny Garbage Collector) interface

#include "legc.h"
#include "lstate.h"
#include "c_types.h"

void legc_set_mode(lua_State *L, int mode, unsigned limit) {
   global_State *g = G(L); 
   
   g->egcmode = mode;
   g->memlimit = limit;
}