diff --git a/src/Func.cc b/src/Func.cc
index 87783a30a9..85d184295d 100644
--- a/src/Func.cc
+++ b/src/Func.cc
@@ -434,7 +434,7 @@ ValPtr ScriptFunc::Invoke(zeek::Args* args, Frame* parent) const {
 
     // Warn if the function returns something, but we returned from
     // the function without an explicit return, or without a value.
-    else if ( GetType()->Yield() && GetType()->Yield()->Tag() != TYPE_VOID &&
+    else if ( GetType()->Yield() && GetType()->Yield()->Tag() != TYPE_VOID && ! GetType()->ExpressionlessReturnOkay() &&
               (flow != FLOW_RETURN /* we fell off the end */ || ! result /* explicit return with no result */) &&
               ! f->HasDelayed() )
         reporter->Warning("non-void function returning without a value: %s", Name());
diff --git a/testing/btest/language/when.zeek b/testing/btest/language/when.zeek
index d0d07b44fa..d8a447e8fd 100644
--- a/testing/btest/language/when.zeek
+++ b/testing/btest/language/when.zeek
@@ -26,6 +26,13 @@ event zeek_init()
 	when [h] ( local hname3 = lookup_addr(h) ) {}
 	timeout to + 2sec {}
 
+	# The following used to generate a spurious warning, so it's here
+	# as a regression test.
+	when ( local res = lookup_addr(127.0.0.1) )
+		{
+		return;
+		}
+
 	print "done";
 }