--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/testsuite/g++.dg/cpp2a/concepts-nonbool1.C	Mon May 25 07:50:57 2020 +0900
@@ -0,0 +1,20 @@
+// PR c++/94186
+// { dg-do compile { target concepts } }
+
+template <typename T>
+struct is_small
+{
+  enum { value = sizeof(T) <= 4 };
+};
+
+template <typename T>
+  requires is_small<T>::value	// { dg-error "bool" }
+void fun(T) {}
+
+template <typename T>
+void fun(T) {}
+
+int main()
+{
+  fun(1);  // { dg-message "" }
+}