diff --git a/include/string.h b/include/string.h
index 7fe76b1f38..509fce2df1 100644
--- a/include/string.h
+++ b/include/string.h
@@ -17,6 +17,8 @@ extern int __strncasecmp (__const char *__s1, __const char *__s2,
 			  size_t __n)
      __attribute_pure__;
 
+extern char *__strdup (__const char *__string)
+     __attribute_malloc__;
 extern char *__strndup (__const char *__string, size_t __n)
      __attribute_malloc__;