diff -ur gcc-9.3.0.orig/gcc/builtins.c gcc-9.3.0/gcc/builtins.c
--- gcc-9.3.0.orig/gcc/builtins.c	2020-03-12 11:07:21.000000000 +0000
+++ gcc-9.3.0/gcc/builtins.c	2020-09-23 22:16:54.815251679 +0000
@@ -4658,6 +4658,7 @@
 static rtx
 expand_builtin_memcmp (tree exp, rtx target, bool result_eq)
 {
+  return NULL_RTX;
   if (!validate_arglist (exp,
  			 POINTER_TYPE, POINTER_TYPE, INTEGER_TYPE, VOID_TYPE))
     return NULL_RTX;