diff --git a/borg/_hashindex.c b/borg/_hashindex.c
index e3a4641da..e9f231903 100644
--- a/borg/_hashindex.c
+++ b/borg/_hashindex.c
@@ -12,10 +12,12 @@
 #include <sys/isa_defs.h>
 #endif
 
-#if (defined(BYTE_ORDER)&&(BYTE_ORDER == BIG_ENDIAN)) || defined(_BIG_ENDIAN)
+#if (defined(BYTE_ORDER)&&(BYTE_ORDER == BIG_ENDIAN)) ||  \
+    (defined(_BIG_ENDIAN)&&defined(__SVR4)&&defined(__sun))
 #define _le32toh(x) __builtin_bswap32(x)
 #define _htole32(x) __builtin_bswap32(x)
-#elif (defined(BYTE_ORDER)&&(BYTE_ORDER == LITTLE_ENDIAN)) || defined(_LITTLE_ENDIAN)
+#elif (defined(BYTE_ORDER)&&(BYTE_ORDER == LITTLE_ENDIAN)) || \
+      (defined(_LITTLE_ENDIAN)&&defined(__SVR4)&&defined(__sun))
 #define _le32toh(x) (x)
 #define _htole32(x) (x)
 #else