diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 504961bdc9..8080c47932 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,8 @@
+2020-02-04  Andrew Burgess  <andrew.burgess@embecosm.com>
+
+	* remote-sim.c (sim_inferior_data::sim_inferior_data): Assert that
+	we don't set the fake simulator ptid to the null_ptid.
+
 2020-02-03  Simon Marchi  <simon.marchi@efficios.com>
 
 	* fork-child.c (gdb_startup_inferior): Use bool instead of int.
diff --git a/gdb/remote-sim.c b/gdb/remote-sim.c
index 281232cc4e..b7ce4672a1 100644
--- a/gdb/remote-sim.c
+++ b/gdb/remote-sim.c
@@ -86,6 +86,7 @@ struct sim_inferior_data {
     : gdbsim_desc (desc),
       remote_sim_ptid (next_pid, 0, next_pid)
   {
+    gdb_assert (remote_sim_ptid != null_ptid);
     ++next_pid;
   }