Use 2 digits exponent format for `printf` family on old MSVC
For conforming C standard.
MODIFY
src/state.c
src/state.c
@@ -41,6 +41,10 @@ mrb_open_core(mrb_allocf f, void *ud)
mrb_init_core(mrb);
+#if !defined(MRB_DISABLE_STDIO) && defined(_MSC_VER) && _MSC_VER < 1900
+ _set_output_format(_TWO_DIGIT_EXPONENT);
+#endif
+
return mrb;
}

Use 2 digits exponent format for `printf` family on old MSVC

For conforming C standard.