diff --git a/contrib/sdk/sources/newlib/include/kos32sys.h b/contrib/sdk/sources/newlib/include/kos32sys.h
index 2d7c740d59..5dbddd901e 100644
--- a/contrib/sdk/sources/newlib/include/kos32sys.h
+++ b/contrib/sdk/sources/newlib/include/kos32sys.h
@@ -291,7 +291,7 @@ int user_free(void *mem)
     __asm__ __volatile__(
     "int $0x40"
     :"=a"(val)
-    :"a"(68),"b"(12),"c"(mem));
+    :"a"(68),"b"(13),"c"(mem));
     return val;
 }