diff --git a/libc/arch-x86/bionic/__bionic_clone.S b/libc/arch-x86/bionic/__bionic_clone.S
index b682b48..f0c58a0 100644
--- a/libc/arch-x86/bionic/__bionic_clone.S
+++ b/libc/arch-x86/bionic/__bionic_clone.S
@@ -45,6 +45,7 @@
 .L_bc_child:
         # We don't want anyone to unwind past this point.
         .cfi_undefined %eip
+        .cfi_undefined %ebp
         call    __start_thread
         hlt