Fixed "select" for "%%" stmt with emty stack

diff --git a/kernel/select.cc b/kernel/select.cc
index a6e675c88cfb533b2349ae4959882b5b9ffbd795..3a91c1e406908ce990608eea44dc538dbf71fea6 100644 (file)
--- a/kernel/select.cc
+++ b/kernel/select.cc
@@ -471,7 +471,8 @@ static void select_stmt(RTLIL::Design *design, std::string arg)
                        select_op_expand(design, arg, 'o');
                } else
                        log_cmd_error("Unknown selection operator '%s'.\n", arg.c_str());
-               select_filter_active_mod(design, work_stack.back());
+               if (work_stack.size() >= 1)
+                       select_filter_active_mod(design, work_stack.back());
                return;
        }