enable MRBC_REQUIRE_64BIT_ALIGNMENT by default.
If 32bit and/or 64bit alignment is required, enable the following line.
*/
// #define MRBC_REQUIRE_32BIT_ALIGNMENT
-// #define MRBC_REQUIRE_64BIT_ALIGNMENT
+#define MRBC_REQUIRE_64BIT_ALIGNMENT
// Debug code.
#if !defined(NDEBUG)
