c++: Add testcase for already fixed PR [PR99209]

This was incidentally fixed by r13-806-g221acd67ca50f8.

	PR c++/99209

gcc/testsuite/ChangeLog:

	* g++.dg/cpp2a/lambda-uneval17.C: New test.

diff --git a/gcc/testsuite/g++.dg/cpp2a/lambda-uneval17.C b/gcc/testsuite/g++.dg/cpp2a/lambda-uneval17.C
new file mode 100644 (file)
index 0000000..74e0f87
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp2a/lambda-uneval17.C
@@ -0,0 +1,17 @@
+// PR c++/99209
+// { dg-do compile { target c++20 } }
+
+constexpr char f(...) = delete;
+constexpr decltype(auto) f_adl(auto a) { return f(a); }
+
+namespace A {
+    constexpr char f(auto) { return 'A'; }
+    template<char TemplateParam = f_adl([]{})> void g(char FunctionParam = f_adl([]{})) {
+        char Local = f_adl([]{});
+    }
+}
+
+namespace B {
+    constexpr char f(auto) = delete;
+    void call() { A::g(); }
+}