diff --git a/configure.ac b/configure.ac
index 4cb56bc..5e23c50 100644
--- a/configure.ac
+++ b/configure.ac
@@ -69,12 +69,17 @@ AC_FUNC_MALLOC
 AC_FUNC_REALLOC
 AC_FUNC_STRTOD
 AC_CHECK_FUNCS([memchr memmove memset strerror strtol])
-AC_CHECK_DECLS([htole64, le64toh],
-               [],
+AC_CHECK_HEADER([sys/endian.h],
                [
-                 AC_CHECK_DECLS([htole64, le64toh], [], [], [#include <endian.h>])
+                 AC_CHECK_DECLS([htole64, le64toh], [], [], [#define _GNU_SOURCE 1 #include <sys/endian.h>])
                ],
-               [#include <sys/endian.h>])
+               [], [])
+
+AC_CHECK_HEADER([endian.h],
+               [
+                 AC_CHECK_DECLS([htole64, le64toh], [], [], [#define _GNU_SOURCE 1 #include <endian.h>])
+               ],
+               [], [])
 
 AC_CONFIG_FILES([Makefile
                  src/Makefile