diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index a63582a3865..1fe42c6eeef 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,7 @@
+2009-11-09  Tom Tromey  <tromey@redhat.com>
+
+	* python/python.c (execute_gdb_command): Copy the argument text.
+
 2009-11-06  Vladimir Prus  <vladimir@codesourcery.com>
 
 	* m68k-tdep.c (m68k_convert_register_p): Correct
diff --git a/gdb/python/python.c b/gdb/python/python.c
index 254bd280a16..77a00693ea3 100644
--- a/gdb/python/python.c
+++ b/gdb/python/python.c
@@ -309,7 +309,11 @@ execute_gdb_command (PyObject *self, PyObject *args)
 
   TRY_CATCH (except, RETURN_MASK_ALL)
     {
-      execute_command (arg, from_tty);
+      /* Copy the argument text in case the command modifies it.  */
+      char *copy = xstrdup (arg);
+      struct cleanup *cleanup = make_cleanup (xfree, copy);
+      execute_command (copy, from_tty);
+      do_cleanups (cleanup);
     }
   GDB_PY_HANDLE_EXCEPTION (except);