[Diagnostics] Restore -Wdeprecated warning when user-declared copy assignment operator is defined as deleted (PR45634)

Solves https://bugs.llvm.org/show_bug.cgi?id=45634
Be more agressive than GCC with -Wdeprecated-copy. Also provide -W(no-)deprecated-copy-user-provided-copy/dtor options to on/off this behaviour.

Reviewed By: Quuxplusone

Differential Revision: https://reviews.llvm.org/D79714

clang/include/clang/Basic/DiagnosticGroups.td

@@ -162,8 +162,12 @@ def CXX11CompatDeprecatedWritableStr :
 def DeprecatedArrayCompare : DiagGroup<"deprecated-array-compare">;
 def DeprecatedAttributes : DiagGroup<"deprecated-attributes">;
 def DeprecatedCommaSubscript : DiagGroup<"deprecated-comma-subscript">;
-def DeprecatedCopy : DiagGroup<"deprecated-copy">;
-def DeprecatedCopyDtor : DiagGroup<"deprecated-copy-dtor">;
+def DeprecatedCopyWithUserProvidedCopy : DiagGroup<"deprecated-copy-with-user-provided-copy">;
+def DeprecatedCopyWithUserProvidedDtor : DiagGroup<"deprecated-copy-with-user-provided-dtor">;
+def DeprecatedCopy : DiagGroup<"deprecated-copy", [DeprecatedCopyWithUserProvidedCopy]>;
+def DeprecatedCopyWithDtor : DiagGroup<"deprecated-copy-with-dtor", [DeprecatedCopyWithUserProvidedDtor]>;
+// For compatibility with GCC.
+def : DiagGroup<"deprecated-copy-dtor", [DeprecatedCopyWithDtor]>;
 def DeprecatedDeclarations : DiagGroup<"deprecated-declarations">;
 def UnavailableDeclarations : DiagGroup<"unavailable-declarations">;
 def UnguardedAvailabilityNew : DiagGroup<"unguarded-availability-new">;
@@ -186,7 +190,7 @@ def Deprecated : DiagGroup<"deprecated", [DeprecatedAnonEnumEnumConversion,
                                           DeprecatedAttributes,
                                           DeprecatedCommaSubscript,
                                           DeprecatedCopy,
-                                          DeprecatedCopyDtor,
+                                          DeprecatedCopyWithDtor,
                                           DeprecatedDeclarations,
                                           DeprecatedDynamicExceptionSpec,
                                           DeprecatedEnumCompare,

clang/include/clang/Basic/DiagnosticSemaKinds.td

@@ -567,15 +567,24 @@ def warn_access_decl_deprecated : Warning<
 def err_access_decl : Error<
   "ISO C++11 does not allow access declarations; "
   "use using declarations instead">;
-def warn_deprecated_copy_operation : Warning<
+def warn_deprecated_copy : Warning<
   "definition of implicit copy %select{constructor|assignment operator}1 "
   "for %0 is deprecated because it has a user-declared copy "
   "%select{assignment operator|constructor}1">,
   InGroup<DeprecatedCopy>, DefaultIgnore;
-def warn_deprecated_copy_dtor_operation : Warning<
+def warn_deprecated_copy_with_dtor : Warning<
   "definition of implicit copy %select{constructor|assignment operator}1 "
   "for %0 is deprecated because it has a user-declared destructor">,
-  InGroup<DeprecatedCopyDtor>, DefaultIgnore;
+  InGroup<DeprecatedCopyWithDtor>, DefaultIgnore;
+def warn_deprecated_copy_with_user_provided_copy: Warning<
+  "definition of implicit copy %select{constructor|assignment operator}1 "
+  "for %0 is deprecated because it has a user-provided copy "
+  "%select{assignment operator|constructor}1">,
+  InGroup<DeprecatedCopyWithUserProvidedCopy>, DefaultIgnore;
+def warn_deprecated_copy_with_user_provided_dtor : Warning<
+  "definition of implicit copy %select{constructor|assignment operator}1 "
+  "for %0 is deprecated because it has a user-provided destructor">,
+  InGroup<DeprecatedCopyWithUserProvidedDtor>, DefaultIgnore;
 def warn_cxx17_compat_exception_spec_in_signature : Warning<
   "mangled name of %0 will change in C++17 due to non-throwing exception "
   "specification in function signature">, InGroup<CXX17CompatMangling>;

clang/lib/Sema/SemaDeclCXX.cpp

@@ -14027,12 +14027,20 @@ static void diagnoseDeprecatedCopyOperation(Sema &S, CXXMethodDecl *CopyOp) {
     assert(UserDeclaredOperation);
   }
 
-  if (UserDeclaredOperation && UserDeclaredOperation->isUserProvided()) {
-    S.Diag(UserDeclaredOperation->getLocation(),
-           isa<CXXDestructorDecl>(UserDeclaredOperation)
-               ? diag::warn_deprecated_copy_dtor_operation
-               : diag::warn_deprecated_copy_operation)
-        << RD << /*copy assignment*/ !isa<CXXConstructorDecl>(CopyOp);
+  if (UserDeclaredOperation) {
+    bool UDOIsUserProvided = UserDeclaredOperation->isUserProvided();
+    bool UDOIsDestructor = isa<CXXDestructorDecl>(UserDeclaredOperation);
+    bool IsCopyAssignment = !isa<CXXConstructorDecl>(CopyOp);
+    unsigned DiagID =
+        (UDOIsUserProvided && UDOIsDestructor)
+            ? diag::warn_deprecated_copy_with_user_provided_dtor
+        : (UDOIsUserProvided && !UDOIsDestructor)
+            ? diag::warn_deprecated_copy_with_user_provided_copy
+        : (!UDOIsUserProvided && UDOIsDestructor)
+            ? diag::warn_deprecated_copy_with_dtor
+            : diag::warn_deprecated_copy;
+    S.Diag(UserDeclaredOperation->getLocation(), DiagID)
+        << RD << IsCopyAssignment;
   }
 }
 

clang/test/SemaCXX/deprecated-copy-with-dtor.cpp

@@ -0,0 +1,13 @@
+// RUN: %clang_cc1 -std=c++11 %s -Wdeprecated -verify
+// RUN: %clang_cc1 -std=c++11 %s -Wdeprecated-copy-dtor -verify
+// RUN: %clang_cc1 -std=c++11 %s -Wdeprecated-copy-with-dtor -verify
+
+class A {
+public:
+   ~A() = default; // expected-warning {{definition of implicit copy constructor for 'A' is deprecated because it has a user-declared destructor}}
+};
+
+void test() {
+  A a1;
+  A a2 = a1; // expected-note {{in implicit copy constructor for 'A' first required here}}
+}

clang/test/SemaCXX/deprecated-copy-with-user-provided-copy.cpp

@@ -0,0 +1,11 @@
+// RUN: %clang_cc1 -std=c++11 %s -Wdeprecated -verify
+// RUN: %clang_cc1 -std=c++11 %s -Wdeprecated-copy-with-user-provided-copy -verify
+
+struct A {
+  A &operator=(const A &); // expected-warning {{definition of implicit copy constructor for 'A' is deprecated because it has a user-provided copy assignment operator}}
+};
+
+void foo() {
+  A a1;
+  A a2(a1); // expected-note {{implicit copy constructor for 'A' first required here}}
+}

clang/test/SemaCXX/deprecated-copy-with-user-provided-dtor.cpp

@@ -0,0 +1,11 @@
+// RUN: %clang_cc1 -std=c++11 %s -Wdeprecated -verify
+// RUN: %clang_cc1 -std=c++11 %s -Wdeprecated-copy-with-user-provided-dtor -verify
+
+struct A {
+  ~A(); // expected-warning {{definition of implicit copy constructor for 'A' is deprecated because it has a user-provided destructor}}
+};
+
+void test() {
+  A a1;
+  A a2(a1); // expected-note {{implicit copy constructor for 'A' first required here}}
+}

clang/test/SemaCXX/deprecated-copy.cpp

@@ -1,23 +1,26 @@
+// RUN: %clang_cc1 -std=c++11 %s -Wdeprecated -verify
 // RUN: %clang_cc1 -std=c++11 %s -Wdeprecated-copy -verify
-// RUN: %clang_cc1 -std=c++11 %s -Wdeprecated-copy-dtor -DDEPRECATED_COPY_DTOR -verify
-// RUN: %clang_cc1 -std=c++11 %s -Wextra -verify
 
-#ifdef DEPRECATED_COPY_DTOR
 struct A {
-  int *ptr;
-  ~A() { delete ptr; } // expected-warning {{definition of implicit copy constructor for 'A' is deprecated because it has a user-declared destructor}}
+    A& operator=(const A&) = default; // expected-warning {{definition of implicit copy constructor for 'A' is deprecated because it has a user-declared copy assignment operator}}
 };
 
-void foo() {
-  A a{};
-  A b = a; // expected-note {{implicit copy constructor for 'A' first required here}}
-}
-#else
 struct B {
-  B &operator=(const B &); // expected-warning {{definition of implicit copy constructor for 'B' is deprecated because it has a user-declared copy assignment operator}}
+    B& operator=(const B&) = delete; // expected-warning {{definition of implicit copy constructor for 'B' is deprecated because it has a user-declared copy assignment operator}}
 };
 
-void bar() {
-  B b1, b2(b1); // expected-note {{implicit copy constructor for 'B' first required here}}
+void test() {
+  A a1;
+  A a2(a1); // expected-note {{implicit copy constructor for 'A' first required here}}
+
+  B b1;
+  B b2(b1); // expected-note {{implicit copy constructor for 'B' first required here}}
 }
-#endif
+
+// PR45634
+struct S {
+    int i;
+    S& operator=(const S&) = delete; // expected-warning {{definition of implicit copy constructor for 'S' is deprecated because it has a user-declared copy assignment operator}}
+};
+
+S test(const S &s) { return S(s); } // expected-note {{implicit copy constructor for 'S' first required here}}

clang/test/SemaCXX/deprecated.cpp

@@ -83,30 +83,31 @@ struct T : private S {
 #if __cplusplus >= 201103L
 namespace DeprecatedCopy {
   struct Assign {
-    Assign &operator=(const Assign&); // expected-warning {{definition of implicit copy constructor for 'Assign' is deprecated because it has a user-declared copy assignment operator}}
+    Assign &operator=(const Assign&); // expected-warning {{definition of implicit copy constructor for 'Assign' is deprecated because it has a user-provided copy assignment operator}}
   };
   Assign a1, a2(a1); // expected-note {{implicit copy constructor for 'DeprecatedCopy::Assign' first required here}}
 
   struct Ctor {
     Ctor();
-    Ctor(const Ctor&); // expected-warning {{definition of implicit copy assignment operator for 'Ctor' is deprecated because it has a user-declared copy constructor}}
+    Ctor(const Ctor&); // expected-warning {{definition of implicit copy assignment operator for 'Ctor' is deprecated because it has a user-provided copy constructor}}
   };
   Ctor b1, b2;
   void f() { b1 = b2; } // expected-note {{implicit copy assignment operator for 'DeprecatedCopy::Ctor' first required here}}
 
   struct Dtor {
     ~Dtor();
-    // expected-warning@-1 {{definition of implicit copy constructor for 'Dtor' is deprecated because it has a user-declared destructor}}
-    // expected-warning@-2 {{definition of implicit copy assignment operator for 'Dtor' is deprecated because it has a user-declared destructor}}
+    // expected-warning@-1 {{definition of implicit copy constructor for 'Dtor' is deprecated because it has a user-provided destructor}}
+    // expected-warning@-2 {{definition of implicit copy assignment operator for 'Dtor' is deprecated because it has a user-provided destructor}}
   };
   Dtor c1, c2(c1); // expected-note {{implicit copy constructor for 'DeprecatedCopy::Dtor' first required here}}
   void g() { c1 = c2; } // expected-note {{implicit copy assignment operator for 'DeprecatedCopy::Dtor' first required here}}
 
   struct DefaultedDtor {
-    ~DefaultedDtor() = default;
-  };
-  DefaultedDtor d1, d2(d1);
-  void h() { d1 = d2; }
+    ~DefaultedDtor() = default; // expected-warning {{definition of implicit copy constructor for 'DefaultedDtor' is deprecated because it has a user-declared destructor}}
+  };                            // expected-warning@-1 {{definition of implicit copy assignment operator for 'DefaultedDtor' is deprecated because it has a user-declared destructor}}
+  DefaultedDtor d1;
+  DefaultedDtor d2(d1);         // expected-note {{in implicit copy constructor for 'DeprecatedCopy::DefaultedDtor' first required here}}
+  void h() { d1 = d2; }         // expected-note {{in implicit copy assignment operator for 'DeprecatedCopy::DefaultedDtor' first required here}}
 }
 #endif