--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/testsuite/g++.dg/lookup/pr87904.C	Thu Feb 13 11:34:05 2020 +0900
@@ -0,0 +1,21 @@
+// PR c++ 87904 ICE failing to initiate deduping
+
+namespace X {
+  void Foo (char);
+}
+
+struct B {
+  friend void Foo (int);
+};
+
+using X::Foo;
+
+void Foo (float);
+void Foo(int);
+
+void frob ()
+{
+  using namespace X;
+
+  Foo (1);
+}