diff --git a/lib/alloca86_64.S b/lib/alloca86_64.S
index ae3c97de..2a70c26e 100644
--- a/lib/alloca86_64.S
+++ b/lib/alloca86_64.S
@@ -27,6 +27,7 @@ p2:
 
     sub     %rax,%rsp
     mov     %rsp,%rax
+    add     $32,%rax
 p3:
     push    %rdx
     ret