Fix `mrb_pool_value` to keep `int64` on 32 bit platforms; fix
MODIFY
include/mruby/irep.h
include/mruby/irep.h
@@ -31,9 +31,7 @@ typedef struct mrb_pool_value {
union {
const char *str;
int32_t i32;
-#if defined(MRB_64BIT) || defined(MRB_INT64)
int64_t i64;
-#endif
#ifndef MRB_NO_FLOAT
mrb_float f;
#endif

Fix `mrb_pool_value` to keep `int64` on 32 bit platforms; fix #5366