[Diagnostics] Put "deprecated copy" warnings into -Wdeprecated-copy

Summary:
GCC 9 added -Wdeprecated-copy (as part of -Wextra). This diagnostic is already implemented in Clang too, just hidden under -Wdeprecated (not on by default).
This patch adds -Wdeprecated-copy and makes it compatible with GCC 9+.
This diagnostic is heavily tested in deprecated.cpp, so I added simple tests just to check we warn when new flag/-Wextra is enabled.

Reviewers: rsmith, dblaikie

Reviewed By: dblaikie

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D70342

diff --git a/clang/include/clang/Basic/DiagnosticGroups.td b/clang/include/clang/Basic/DiagnosticGroups.td
index 6b83bf5..5bfb3de 100644 (file)
--- a/clang/include/clang/Basic/DiagnosticGroups.td
+++ b/clang/include/clang/Basic/DiagnosticGroups.td
@@ -128,6 +128,8 @@ def CXX11CompatDeprecatedWritableStr :
 
 def DeprecatedAttributes : DiagGroup<"deprecated-attributes">;
 def DeprecatedCommaSubscript : DiagGroup<"deprecated-comma-subscript">;
+def DeprecatedCopy : DiagGroup<"deprecated-copy">;
+def DeprecatedCopyDtor : DiagGroup<"deprecated-copy-dtor">;
 def DeprecatedDeclarations : DiagGroup<"deprecated-declarations">;
 def UnavailableDeclarations : DiagGroup<"unavailable-declarations">;
 def UnguardedAvailabilityNew : DiagGroup<"unguarded-availability-new">;
@@ -147,6 +149,8 @@ def DeprecatedWritableStr : DiagGroup<"deprecated-writable-strings",
 // FIXME: Why is DeprecatedImplementations not in this group?
 def Deprecated : DiagGroup<"deprecated", [DeprecatedAttributes,
                                           DeprecatedCommaSubscript,
+                                          DeprecatedCopy,
+                                          DeprecatedCopyDtor,
                                           DeprecatedDeclarations,
                                           DeprecatedDynamicExceptionSpec,
                                           DeprecatedIncrementBool,
@@ -812,6 +816,7 @@ def Move : DiagGroup<"move", [
   ]>;
 
 def Extra : DiagGroup<"extra", [
+    DeprecatedCopy,
     MissingFieldInitializers,
     IgnoredQualifiers,
     InitializerOverrides,

diff --git a/clang/include/clang/Basic/DiagnosticSemaKinds.td b/clang/include/clang/Basic/DiagnosticSemaKinds.td
index eb05a7e..6e4b601 100644 (file)
--- a/clang/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/clang/include/clang/Basic/DiagnosticSemaKinds.td
@@ -551,9 +551,13 @@ def err_access_decl : Error<
   "use using declarations instead">;
 def warn_deprecated_copy_operation : Warning<
   "definition of implicit copy %select{constructor|assignment operator}1 "
-  "for %0 is deprecated because it has a user-declared "
-  "%select{copy %select{assignment operator|constructor}1|destructor}2">,
-  InGroup<Deprecated>, DefaultIgnore;
+  "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<
+  "definition of implicit copy %select{constructor|assignment operator}1 "
+  "for %0 is deprecated because it has a user-declared destructor">,
+  InGroup<DeprecatedCopyDtor>, 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>;

diff --git a/clang/lib/Sema/SemaDeclCXX.cpp b/clang/lib/Sema/SemaDeclCXX.cpp
index 14989cd..d720018 100644 (file)
--- a/clang/lib/Sema/SemaDeclCXX.cpp
+++ b/clang/lib/Sema/SemaDeclCXX.cpp
@@ -12434,9 +12434,10 @@ static void diagnoseDeprecatedCopyOperation(Sema &S, CXXMethodDecl *CopyOp) {
 
   if (UserDeclaredOperation) {
     S.Diag(UserDeclaredOperation->getLocation(),
-         diag::warn_deprecated_copy_operation)
-      << RD << /*copy assignment*/!isa<CXXConstructorDecl>(CopyOp)
-      << /*destructor*/isa<CXXDestructorDecl>(UserDeclaredOperation);
+           isa<CXXDestructorDecl>(UserDeclaredOperation)
+               ? diag::warn_deprecated_copy_dtor_operation
+               : diag::warn_deprecated_copy_operation)
+        << RD << /*copy assignment*/ !isa<CXXConstructorDecl>(CopyOp);
   }
 }
 

diff --git a/clang/test/SemaCXX/deprecated-copy.cpp b/clang/test/SemaCXX/deprecated-copy.cpp
new file mode 100644 (file)
index 0000000..4d3e798
--- /dev/null
+++ b/clang/test/SemaCXX/deprecated-copy.cpp
@@ -0,0 +1,23 @@
+// 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}}
+};
+
+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}}
+};
+
+void bar() {
+  B b1, b2(b1); // expected-note {{implicit copy constructor for 'B' first required here}}
+}
+#endif