c++: Add testcase for already fixed PR [PR94102]

We correctly accept this testcase since r11-1571.

gcc/testsuite/ChangeLog:

	PR c++/94102
	* g++.dg/cpp1z/class-deduction87.C: New test.

diff --git a/gcc/testsuite/g++.dg/cpp1z/class-deduction87.C b/gcc/testsuite/g++.dg/cpp1z/class-deduction87.C
new file mode 100644 (file)
index 0000000..37296a4
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp1z/class-deduction87.C
@@ -0,0 +1,15 @@
+// PR c++/94102
+// { dg-do compile { target c++17 } }
+
+namespace std {
+  template <typename _Tp> using decay_t = _Tp;
+}
+template <typename... B> struct Merged : B... {
+  template <typename... T> Merged(T... t) : B(t)... {}
+};
+template <typename... T> Merged(T...) -> Merged<std::decay_t<T>...>;
+int main() {
+  auto l1 = [] {};
+  auto l2 = [](int i) { return i; };
+  Merged(l1, l2);
+}