Verify that __BYTE_ORDER__ is defined before testing it

Author: kriszyp

src/env.cpp

@@ -14,7 +14,7 @@ using namespace Napi;
 
 #if defined (__linux)
 #include <endian.h> // For __BYTE_ORDER, __BIG_ENDIAN
-#if __BYTE_ORDER == __BIG_ENDIAN
+#if defined(__BYTE_ORDER__)&&(__BYTE_ORDER__ == __ORDER_BIG_ENDIAN__)
 #define BE64_TO_HOST(x) (x)
 #else
 #define BE64_TO_HOST(x) bswap_64((x))

src/ordered-binary.cpp

@@ -34,7 +34,7 @@ int compareFast(const MDB_val *a, const MDB_val *b) {
             bVal = *((uint8_t*) dataB);
         } else {
             aVal = ntohl(*dataA);
-            #if __BYTE_ORDER == __BIG_ENDIAN
+            #if defined(__BYTE_ORDER__)&&(__BYTE_ORDER__ == __ORDER_BIG_ENDIAN__)
             bVal = remaining == 2 ? *dataB & 0xffff0000 : *dataB & 0xffffff00;
             #else
             bVal = remaining == 2 ? (*((uint8_t*) dataB) << 24) + (*((uint8_t*) dataB + 1) << 16) :