diff --git a/include/libiberty.h b/include/libiberty.h
index f2cf573..6aa1f20 100644
--- a/include/libiberty.h
+++ b/include/libiberty.h
@@ -613,8 +613,10 @@
 /* Like sprintf but provides a pointer to malloc'd storage, which must
    be freed by the caller.  */
 
+#ifndef asprintf
 extern int asprintf (char **, const char *, ...) ATTRIBUTE_PRINTF_2;
 #endif
+#endif
 
 #if !HAVE_DECL_VASPRINTF
 /* Like vsprintf but provides a pointer to malloc'd storage, which