diff --git a/netlist.cc b/netlist.cc
index 51cf898f6..72b5b8e99 100644
--- a/netlist.cc
+++ b/netlist.cc
@@ -2649,6 +2649,7 @@ DelayType NetRepeat::delay_type() const
 
 DelayType NetTaskDef::delay_type() const
 {
+      if (proc_ == 0) return NO_DELAY;
       return proc_->delay_type();
 }