--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/testsuite/g++.dg/cpp1z/constexpr-if33.C	Thu Feb 13 11:34:05 2020 +0900
@@ -0,0 +1,16 @@
+// PR c++/93324 - ICE with -Wall on constexpr if.
+// { dg-do compile { target c++17 } }
+// { dg-options "-Wall" }
+
+struct {
+  template <int>
+  static constexpr bool a() { return 0; }
+} e;
+
+template <typename>
+void d()
+{
+  auto c(e);
+  using b = decltype(c);
+  if constexpr (b::a<2>());
+}