diff --git a/stdlib/strtoull.c b/stdlib/strtoull.c
index ef808298d8..80ccf91c5e 100644
--- a/stdlib/strtoull.c
+++ b/stdlib/strtoull.c
@@ -21,5 +21,7 @@
 
 #include <strtoul.c>
 
+#ifdef _LIBC
 strong_alias (__strtoull_internal, __strtouq_internal)
 weak_alias (strtoull, strtouq)
+#endif