flatten: clarify confusing error message.

diff --git a/passes/techmap/flatten.cc b/passes/techmap/flatten.cc
index ec5f83fb03f72201a0bc90f3ad3257163890e6ec..f35b7ff60508011a3fb7f031dafbec0d0ef999ea 100644 (file)
--- a/passes/techmap/flatten.cc
+++ b/passes/techmap/flatten.cc
@@ -211,7 +211,7 @@ struct FlattenWorker
                        log_assert(new_conn.first.size() == new_conn.second.size());
 
                        if (sigmap(new_conn.first).has_const())
-                               log_error("Mismatch in directionality for cell port %s.%s.%s: %s <= %s\n",
+                               log_error("Cell port %s.%s.%s is driving constant bits: %s <= %s\n",
                                        log_id(module), log_id(cell), log_id(port_it.first), log_signal(new_conn.first), log_signal(new_conn.second));
 
                        module->connect(new_conn);