diff --git a/src/borg/_endian.h b/src/borg/_endian.h
new file mode 100644
index 000000000..645e40784
--- /dev/null
+++ b/src/borg/_endian.h
@@ -0,0 +1,27 @@
+#include <unistd.h>
+#include <stdlib.h>
+#include <stdint.h>
+
+#if defined (__SVR4) && defined (__sun)
+#include <sys/isa_defs.h>
+#endif
+
+#if (defined(BYTE_ORDER) && defined(BIG_ENDIAN) && (BYTE_ORDER == BIG_ENDIAN)) ||  \
+    (defined(__BYTE_ORDER__) && defined(__ORDER_BIG_ENDIAN__) && (__BYTE_ORDER__ == __ORDER_BIG_ENDIAN__)) || \
+    (defined(_BIG_ENDIAN) && defined(__SVR4) && defined(__sun))
+#define BORG_BIG_ENDIAN 1
+#elif (defined(BYTE_ORDER) && defined(LITTLE_ENDIAN) && (BYTE_ORDER == LITTLE_ENDIAN)) || \
+      (defined(__BYTE_ORDER__) && defined(__ORDER_LITTLE_ENDIAN__) && (__BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__)) || \
+      (defined(_LITTLE_ENDIAN) && defined(__SVR4) && defined(__sun))
+#define BORG_BIG_ENDIAN 0
+#else
+#error Unknown byte order
+#endif
+
+#if BORG_BIG_ENDIAN
+#define _le32toh(x) __builtin_bswap32(x)
+#define _htole32(x) __builtin_bswap32(x)
+#else
+#define _le32toh(x) (x)
+#define _htole32(x) (x)
+#endif
diff --git a/src/borg/_hashindex.c b/src/borg/_hashindex.c
index 763d0a250..c6435d85b 100644
--- a/src/borg/_hashindex.c
+++ b/src/borg/_hashindex.c
@@ -10,29 +10,7 @@
 #include <fcntl.h>
 #include <unistd.h>
 
-#if defined (__SVR4) && defined (__sun)
-#include <sys/isa_defs.h>
-#endif
-
-#if (defined(BYTE_ORDER) && (BYTE_ORDER == BIG_ENDIAN)) ||  \
-    (defined(__BYTE_ORDER__) && (__BYTE_ORDER__ == __ORDER_BIG_ENDIAN__)) || \
-    (defined(_BIG_ENDIAN) && defined(__SVR4)&&defined(__sun))
-#define BORG_BIG_ENDIAN 1
-#elif (defined(BYTE_ORDER) && (BYTE_ORDER == LITTLE_ENDIAN)) || \
-      (defined(__BYTE_ORDER__) && (__BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__)) || \
-      (defined(_LITTLE_ENDIAN) && defined(__SVR4)&&defined(__sun))
-#define BORG_BIG_ENDIAN 0
-#else
-#error Unknown byte order
-#endif
-
-#if BORG_BIG_ENDIAN
-#define _le32toh(x) __builtin_bswap32(x)
-#define _htole32(x) __builtin_bswap32(x)
-#else
-#define _le32toh(x) (x)
-#define _htole32(x) (x)
-#endif
+#include "_endian.h"
 
 #define MAGIC "BORG_IDX"
 #define MAGIC_LEN 8
diff --git a/src/borg/algorithms/crc32_slice_by_8.c b/src/borg/algorithms/crc32_slice_by_8.c
index 2924285f6..dcfd8b8f9 100644
--- a/src/borg/algorithms/crc32_slice_by_8.c
+++ b/src/borg/algorithms/crc32_slice_by_8.c
@@ -9,6 +9,8 @@
 // size_t
 #include <stddef.h>
 
+#include "../_endian.h"
+
 /// compute CRC32 (Slicing-by-8 algorithm), unroll inner loop 4 times
 uint32_t crc32_4x8bytes(const void* data, size_t length, uint32_t previousCrc32);
 
@@ -23,23 +25,6 @@ uint32_t crc32_4x8bytes(const void* data, size_t length, uint32_t previousCrc32)
 /// zlib's CRC32 polynomial
 const uint32_t Polynomial = 0xEDB88320;
 
-/// swap endianness
-#if defined (__SVR4) && defined (__sun)
-#include <sys/isa_defs.h>
-#endif
-
-#if (defined(BYTE_ORDER)&&(BYTE_ORDER == BIG_ENDIAN)) ||  \
-    (defined(_BIG_ENDIAN)&&defined(__SVR4)&&defined(__sun))
-#define _le32toh(x) __builtin_bswap32(x)
-#define BORG_BIG_ENDIAN
-#elif (defined(BYTE_ORDER)&&(BYTE_ORDER == LITTLE_ENDIAN)) || \
-      (defined(_LITTLE_ENDIAN)&&defined(__SVR4)&&defined(__sun))
-#define _le32toh(x) (x)
-#define BORG_LITTLE_ENDIAN
-#else
-#error Unknown byte order
-#endif
-
 // //////////////////////////////////////////////////////////
 // constants
 
@@ -358,7 +343,7 @@ uint32_t crc32_slice_by_8(const void* data, size_t length, uint32_t previousCrc3
     size_t unrolling;
     for (unrolling = 0; unrolling < Unroll; unrolling++)
     {
-#ifdef BORG_BIG_ENDIAN
+#if BORG_BIG_ENDIAN
       uint32_t one = *current++ ^ _le32toh(crc);
       uint32_t two = *current++;
       crc = Crc32Lookup[0][ two      & 0xFF] ^