Index: tests/concurrent/.expect/ctor-check.txt
===================================================================
--- tests/concurrent/.expect/ctor-check.txt	(revision a83012bff7941cf76bd77512855de9fa1007f46d)
+++ tests/concurrent/.expect/ctor-check.txt	(revision a83012bff7941cf76bd77512855de9fa1007f46d)
@@ -0,0 +1,8 @@
+concurrent/ctor-check.cfa:11:1 error: constructors cannot have mutex parameters
+?{}: function
+... with parameters
+  lvalue reference to instance of struct Empty with body
+... returning nothing
+ with body
+  Compound Statement:
+
Index: tests/concurrent/ctor-check.cfa
===================================================================
--- tests/concurrent/ctor-check.cfa	(revision a83012bff7941cf76bd77512855de9fa1007f46d)
+++ tests/concurrent/ctor-check.cfa	(revision a83012bff7941cf76bd77512855de9fa1007f46d)
@@ -0,0 +1,15 @@
+#include <monitor.hfa>
+
+monitor Empty {};
+
+struct Test {};
+
+// Should work:
+void ?{}(Test & this, Empty & mutex mon) {}
+
+// Should not work:
+void ?{}(Empty & mutex this) {}
+
+int main(void) {
+	printf("done\n");
+}