diff --git a/config.h.in b/config.h.in
index f9155955..b586808a 100644
--- a/config.h.in
+++ b/config.h.in
@@ -6,6 +6,18 @@
 /* Define to 1 if you have the <byteswap.h> header file. */
 #undef HAVE_BYTESWAP_H
 
+/* Define to 1 if you have the declaration of `__bswap_constant_16', and to 0
+   if you don't. */
+#undef HAVE_DECL___BSWAP_CONSTANT_16
+
+/* Define to 1 if you have the declaration of `__bswap_constant_32', and to 0
+   if you don't. */
+#undef HAVE_DECL___BSWAP_CONSTANT_32
+
+/* Define to 1 if you have the declaration of `__bswap_constant_64', and to 0
+   if you don't. */
+#undef HAVE_DECL___BSWAP_CONSTANT_64
+
 /* Define to 1 if you have the <dlfcn.h> header file. */
 #undef HAVE_DLFCN_H
 
diff --git a/include/ntfs/endians.h b/include/ntfs/endians.h
index e43e7cc6..bb8cf543 100644
--- a/include/ntfs/endians.h
+++ b/include/ntfs/endians.h
@@ -92,13 +92,13 @@
 #define __cpu_to_le64(x) bswap_64(x)
 
 /* For architectures that do not provide some/all of the constant versions. */
-#ifndef __bswap_constant_16
+#if defined HAVE_DECL___BSWAP_CONSTANT_16 && !HAVE_DECL___BSWAP_CONSTANT_16
 #define __bswap_constant_16(x) bswap_16(x)
 #endif
-#ifndef __bswap_constant_32
+#if defined HAVE_DECL___BSWAP_CONSTANT_32 && !HAVE_DECL___BSWAP_CONSTANT_32
 #define __bswap_constant_32(x) bswap_32(x)
 #endif
-#ifndef __bswap_constant_64
+#if defined HAVE_DECL___BSWAP_CONSTANT_64 && !HAVE_DECL___BSWAP_CONSTANT_64
 #define __bswap_constant_64(x) bswap_64(x)
 #endif