Add test case

Author: dmpolukhin

clang/test/Headers/crash-instantiated-in-scope-cxx-modules4.cpp

@@ -0,0 +1,110 @@
+// RUN: rm -fR %t
+// RUN: split-file %s %t
+// RUN: cd %t
+// RUN: %clang_cc1 -verify -std=c++20 -x c++ -fmodule-map-file=modules.map -fmodule-name=foo1 -emit-module modules.map -o foo1.pcm
+// RUN: %clang_cc1 -verify -std=c++20 -x c++ -fmodule-map-file=modules.map -fmodule-name=foo2 -emit-module modules.map -o foo2.pcm
+// RUN: %clang_cc1 -verify -std=c++20 -x c++ -fmodule-map-file=modules.map -fmodule-file=foo1.pcm -fmodule-file=foo2.pcm server.cc
+
+//--- functional
+#pragma once
+
+namespace std {
+template <class> class function {};
+} // namespace std
+
+//--- foo.h
+#pragma once
+
+class MethodHandler {
+ public:
+  virtual ~MethodHandler() {}
+  struct HandlerParameter {
+    HandlerParameter();
+  };
+  virtual void RunHandler(const HandlerParameter &param);
+};
+
+template <class RequestType, class ResponseType>
+class CallbackUnaryHandler : public MethodHandler {
+ public:
+  explicit CallbackUnaryHandler();
+
+  void RunHandler(const HandlerParameter &param) final {
+    void *call = nullptr;
+    (void)[call](bool){};
+  }
+};
+
+//--- foo1.h
+// expected-no-diagnostics
+#pragma once
+
+#include "functional"
+
+#include "foo.h"
+
+class A;
+
+class ClientAsyncResponseReaderHelper {
+   public:
+      using t = std::function<void(A)>;
+        static void SetupRequest(t finish);
+};
+
+//--- foo2.h
+// expected-no-diagnostics
+#pragma once
+
+#include "foo.h"
+
+template <class BaseClass>
+class a : public BaseClass {
+ public:
+  a() { [[maybe_unused]] CallbackUnaryHandler<int, int> a; }
+};
+
+//--- modules.map
+module "foo" {
+  export *
+  module "foo.h" {
+    export *
+    textual header "foo.h"
+  }
+}
+
+module "foo1" {
+  export *
+  module "foo1.h" {
+    export *
+    header "foo1.h"
+  }
+
+  use "foo"
+}
+
+module "foo2" {
+  export *
+  module "foo2.h" {
+    export *
+    header "foo2.h"
+  }
+
+  use "foo"
+}
+
+//--- server.cc
+// expected-no-diagnostics
+#include "functional"
+
+#include "foo1.h"
+#include "foo2.h"
+
+std::function<void()> on_emit;
+
+template <class RequestType, class ResponseType>
+class CallbackUnaryHandler;
+
+class s {};
+class hs final : public a<s> {
+  explicit hs() {}
+};