diff --git a/builtins/read.def b/builtins/read.def
index c4a668a..1b87faa 100644
--- a/builtins/read.def
+++ b/builtins/read.def
@@ -642,6 +642,12 @@ assign_vars:
 	  xfree (input_string);
 	  return EXECUTION_FAILURE;	/* readonly or noassign */
 	}
+      if (assoc_p (var))
+	{
+          builtin_error (_("%s: cannot convert associative to indexed array"), arrayname);
+	  xfree (input_string);
+	  return EXECUTION_FAILURE;	/* existing associative array */
+	}
       array_flush (array_cell (var));
 
       alist = list_string (input_string, ifs_chars, 0);
diff --git a/patchlevel.h b/patchlevel.h
index dd41e76..5de379f 100644
--- a/patchlevel.h
+++ b/patchlevel.h
@@ -25,6 +25,6 @@
    regexp `^#define[ 	]*PATCHLEVEL', since that's what support/mkversion.sh
    looks for to find the patch level (for the sccs version string). */
 
-#define PATCHLEVEL 16
+#define PATCHLEVEL 17
 
 #endif /* _PATCHLEVEL_H_ */