Just assume Windows is little-endian.

Author: elprans

asyncpg/protocol/hton.h

@@ -12,10 +12,11 @@
 #define __BIG_ENDIAN BIG_ENDIAN
 #define __LITTLE_ENDIAN LITTLE_ENDIAN
 #elif defined(_WIN32) || defined(_WIN64) || defined(__WINDOWS__)
-#include <sys/param.h>
-#define __BYTE_ORDER BYTE_ORDER
-#define __BIG_ENDIAN BIG_ENDIAN
-#define __LITTLE_ENDIAN LITTLE_ENDIAN
+/* Assume Windows is always LE.  There seems to be no reliable way
+   to detect endianness there */
+#define __LITTLE_ENDIAN 1234
+#define __BIG_ENDIAN 4321
+#define __BYTE_ORDER __LITTLE_ENDIAN
 #else
 #error Cannot determine platform byte order.
 #endif