--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/testsuite/g++.dg/warn/Wmismatched-tags.C	Thu Feb 13 11:34:05 2020 +0900
@@ -0,0 +1,278 @@
+/* PR c++/61339 - add mismatch between struct and class
+   Test to verify that -Wmismatched-tags is issued for declarations
+   of the same class using different class-ids.
+   { dg-do compile }
+   { dg-options "-Wmismatched-tags" } */
+
+namespace Classes
+{
+class A;
+class A;
+
+struct B;
+struct B;
+
+union C;
+union C;
+
+struct D;                   // { dg-warning "Classes::D' declared with a mismatched class-key 'struct'" }
+class D { };                // { dg-message "Classes::D' defined as 'class' here" }
+
+class E;                    // { dg-warning "Classes::E' declared with a mismatched class-key 'class'" }
+struct E { };               // { dg-message "Classes::E' defined as 'struct' here" }
+
+class D;
+struct E;
+
+class D;
+struct E;
+
+struct D;                   // { dg-warning "Classes::D' declared with a mismatched class-key" }
+
+class E;                    // { dg-warning "Classes::E' declared with a mismatched class-key" }
+
+class F;                    // { dg-message "Classes::F' first declared as 'class' here" }
+class F;
+
+struct G { };               // { dg-message "Classes::G' defined as 'struct' here" }
+}   // namespace Classes
+
+
+namespace Classes
+{
+class A;
+struct B;
+union C;
+class D;
+struct E;
+
+struct F;                   // { dg-warning "Classes::F' declared with a mismatched class-key" }
+
+struct G;
+}
+
+// Verify that the correct hint is provided, one to remove the class-key
+// when it's redundant, and one to (only) replace it with the correct one
+// when it's needed to disambiguate the reference to the class type.
+namespace RemoveOrReplace
+{
+struct Func;
+class Func;                 // { dg-warning "RemoveOrReplace::Func' declared with a mismatched class-key 'class'" }
+                            // { dg-message "replace the class-key with 'struct'" "hint to remove" { target *-*-* } .-1 }
+
+void Func ();
+
+class Func;                 // { dg-warning "RemoveOrReplace::Func' declared with a mismatched class-key 'class'" }
+                            // { dg-message "replace the class-key with 'struct'" "hint to replace" { target *-*-* } .-1 }
+
+class Var;
+struct Var;                  // { dg-warning "RemoveOrReplace::Var' declared with a mismatched class-key 'struct'" }
+                            // { dg-message "replace the class-key with 'class'" "hint to remove" { target *-*-* } .-1 }
+void f (struct Var*);       // { dg-warning "RemoveOrReplace::Var' declared with a mismatched class-key 'struct'" }
+                            // { dg-message "remove the class-key or replace it with 'class'" "hint to remove" { target *-*-* } .-1 }
+
+int Var;
+
+struct Var;                  // { dg-warning "RemoveOrReplace::Var' declared with a mismatched class-key 'struct'" }
+                            // { dg-message "replace the class-key with 'class'" "hint to replace" { target *-*-* } .-1 }
+}
+
+namespace GlobalObjects
+{
+class A;                    // { dg-message "'GlobalObjects::A' first declared as 'class' here" }
+struct B;                   // { dg-message "'GlobalObjects::B' first declared as 'struct' here" }
+class C { };                // { dg-message "'GlobalObjects::C' defined as 'class' here" }
+
+extern A a0;
+extern class A a1;
+extern class A a2;
+
+extern B b0;
+extern struct B b1;
+extern struct B b2;
+
+extern struct A a3;         // { dg-warning "GlobalObjects::A' declared with a mismatched class-key" }
+extern class A a4;
+
+extern class B b3;          // { dg-warning "GlobalObjects::B' declared with a mismatched class-key" }
+extern struct B b4;
+
+extern struct C c[];        // { dg-warning "GlobalObjects::C' declared with a mismatched class-key" }
+                            // { dg-message "remove the class-key or replace it with 'class'" "hint to remove" { target *-*-* } .-1 }
+
+extern char
+arr[sizeof (struct C)];     // { dg-warning "GlobalObjects::C' declared with a mismatched class-key" }
+                            // { dg-message "remove the class-key or replace it with 'class'" "hint to remove" { target *-*-* } .-1 }
+}   // namespace GlobalObjects
+
+
+namespace LocalObjects
+{
+class A;                    // { dg-message "LocalObjects::A' first declared as 'class' here" }
+struct B;                   // { dg-message "LocalObjects::B' first declared as 'struct' here" }
+
+void f (A*, B&)
+{
+  class A *a1;
+  class A *a2;
+
+  struct B *b1;
+  struct B *b2;
+
+  struct A *a3;             // { dg-warning "LocalObjects::A' declared with a mismatched class-key" }
+  class A *a4;
+
+  class B *b3;              // { dg-warning "LocalObjects::B' declared with a mismatched class-key" }
+  struct B *b4;
+}
+
+void g (struct A*);         // { dg-warning "LocalObjects::A' declared with a mismatched class-key" }
+
+}   // namespace LocalObjects
+
+
+namespace MemberClasses
+{
+struct A { struct B; };
+struct C { struct D; struct D; struct D { }; };
+struct E { class F; class F { }; class F; };
+
+struct G {
+  struct H;                 // { dg-message "MemberClasses::G::H' first declared as 'struct' here" }
+  class H;                  // { dg-warning "MemberClasses::G::H' declared with a mismatched class-key" }
+  class I { };              // { dg-message "MemberClasses::G::I' defined as 'class' here" }
+  struct I;                 // { dg-warning "MemberClasses::G::I' declared with a mismatched class-key" }
+};
+}   // namespace MemberClasses
+
+
+namespace DataMembers
+{
+struct A { struct B *p; };
+struct C { struct D *p; struct D *q; struct D { } d; };
+struct E { class F &r; class F { } f; class F *p; };
+
+class G;                    // { dg-message "DataMembers::G' first declared as 'class' here" }
+struct H;                   // { dg-message "DataMembers::H' first declared as 'struct' here" }
+
+struct I {
+  struct G *p0;             // { dg-warning "DataMembers::G' declared with a mismatched class-key" }
+  class G *p1;
+
+  struct H &r0;
+  class H &r1;              // { dg-warning "DataMembers::H' declared with a mismatched class-key" }
+
+  class J { };              // { dg-message "DataMembers::I::J' defined as 'class' here" }
+  struct K { };             // { dg-message "DataMembers::I::K' defined as 'struct' here" }
+
+  class J j0;
+  class K k0;               // { dg-warning "DataMembers::I::K' declared with a mismatched class-key" }
+
+  struct J j1;              // { dg-warning "DataMembers::I::J' declared with a mismatched class-key" }
+  struct K k1;
+};
+}   // namespace DataMembers
+
+
+namespace Templates
+{
+template <int> class A;
+template <int> class A;
+
+template <int> struct B;
+template <int> struct B;
+
+template <int> union C;
+template <int> union C;
+
+template <int> struct D;    // { dg-warning "Templates::D\[^\n\r]*' declared with a mismatched class-key" }
+template <int>
+class D                     // { dg-message "Templates::D\[^\n\r]*' defined as 'class' here" }
+{ public: D (); };
+
+template <int> class E;     // { dg-warning "Templates::E\[^\n\r]*' declared with a mismatched class-key" }
+template <int>
+struct E                    // { dg-message "Templates::E\[^\n\r]*' defined as 'struct' here" }
+{ int i; };
+
+template <int> class D;
+template <int> struct E;
+
+template <int>
+struct D;                   // { dg-warning "Templates::D\[^\n\r]*' declared with a mismatched class-key" }
+                            // { dg-message "replace the class-key with 'class'" "hint" { target *-*-* } .-1 }
+}   // namespace Templates
+
+
+namespace ExplicitSpecializations
+{
+template <int> class A;
+template <> class A<0>;
+template <> struct A<1>;
+template <> struct A<1> { };
+
+template <int> struct B;
+template <> struct B<0>;
+template <> class B<1>;
+template <> class B<2> { public: B (); };
+
+template <int> union C;
+template <> union C<0>;
+
+template <int> class D;
+template <> class D<0>;     // { dg-warning "ExplicitSpecializations::D\[^\n\r]*' declared with a mismatched class-key " }
+template <>
+struct D<0> { };            // { dg-message "ExplicitSpecializations::D\[^\n\r]*' defined as 'struct' here" }
+
+template <int> struct E;
+template <> struct E<0>;    // { dg-warning "ExplicitSpecializations::E\[^\n\r]*' declared with a mismatched class-key" }
+template <>
+class E<0> { };             // { dg-message "ExplicitSpecializations::E\[^\n\r]*' defined as 'class' here" }
+
+template <int> struct F;
+template <> class F<0> { }; // { dg-message "ExplicitSpecializations::F\[^\n\r]*' defined as 'class' here" }
+
+template <>
+struct F<0>;                // { dg-warning "ExplicitSpecializations::F\[^\n\r]*' declared with a mismatched class-key" }
+}   // namespace ExplicitSpecializations
+
+
+namespace PartialSpecializations
+{
+template <class> class A;
+template <class T> struct A<const T>;
+template <class T> struct A<volatile T>;
+
+template <class> struct B;
+template <class T> class B<const T>;
+template <class T> class B<volatile T>;
+
+template <class> class C { };
+template <class T> struct C<const T> { };
+template <class T> struct C<volatile T> { };
+
+template <class> struct D { };
+template <class T> class D<const T> { };
+template <class T> class D<volatile T> { };
+
+template <class> class E;
+template <class T>
+struct E<const T>;          // { dg-message "PartialSpecializations::E<const T>' first declared as 'struct' here" }
+
+template <class T>
+class E<const T>;           // { dg-warning "PartialSpecializations::E<const T>' declared with a mismatched class-key" }
+
+template <class> class F;
+template <class T>
+class F<const T>;           // { dg-message "PartialSpecializations::F<const T>' first declared as 'class' here" }
+template <class T>
+struct F<const T>;          // { dg-warning "PartialSpecializations::F<const T>' declared with a mismatched class-key" }
+}   // namespace PartialSpecializations
+
+
+namespace Classes
+{
+struct G;
+
+class G;                    // { dg-warning "Classes::G' declared with a mismatched class-key 'class'" }
+}