Implement DR7

Disallowing deriving from classes that have private virtual base classes
except in instances where the deriving class would be able to cast
itself to the private virtual base via a different derivation.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@183462 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/include/clang/Basic/DiagnosticSemaKinds.td b/include/clang/Basic/DiagnosticSemaKinds.td
index c328e71057e90c4c9bee429e176f1c1394a8e90d..40ef1ac75aef9ef102e7ca927c17f3946ae7d328 100644 (file)
--- a/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/include/clang/Basic/DiagnosticSemaKinds.td
@@ -1011,8 +1011,8 @@ def err_access_dtor_base :
     Error<"base class %0 has %select{private|protected}1 destructor">,
     AccessControl;
 def err_access_dtor_vbase :
-    Error<"inherited virtual base class %0 has "
-    "%select{private|protected}1 destructor">,
+    Error<"inherited virtual base class %1 has "
+    "%select{private|protected}2 destructor">,
     AccessControl;
 def err_access_dtor_temp :
     Error<"temporary of type %0 has %select{private|protected}1 destructor">,

diff --git a/lib/Sema/SemaDeclCXX.cpp b/lib/Sema/SemaDeclCXX.cpp
index 573738cedb9ebeb9187a850f7c92185ac1c2c784..059c3720d67ba427ae52435e070e36f8aca52c79 100644 (file)
--- a/lib/Sema/SemaDeclCXX.cpp
+++ b/lib/Sema/SemaDeclCXX.cpp
@@ -1311,7 +1311,7 @@ Sema::CheckBaseSpecifier(CXXRecordDecl *Class,
   assert(BaseDecl && "Record type has no declaration");
   BaseDecl = BaseDecl->getDefinition();
   assert(BaseDecl && "Base type is not incomplete, but has no definition");
-  CXXRecordDecl * CXXBaseDecl = cast<CXXRecordDecl>(BaseDecl);
+  CXXRecordDecl *CXXBaseDecl = cast<CXXRecordDecl>(BaseDecl);
   assert(CXXBaseDecl && "Base type is not a C++ type");
 
   // C++ [class]p3:
@@ -3806,10 +3806,17 @@ Sema::MarkBaseAndMemberDestructorsReferenced(SourceLocation Location,
 
     CXXDestructorDecl *Dtor = LookupDestructor(BaseClassDecl);
     assert(Dtor && "No dtor found for BaseClassDecl!");
-    CheckDestructorAccess(ClassDecl->getLocation(), Dtor,
-                          PDiag(diag::err_access_dtor_vbase)
-                            << VBase->getType(),
-                          Context.getTypeDeclType(ClassDecl));
+    if (CheckDestructorAccess(
+            ClassDecl->getLocation(), Dtor,
+            PDiag(diag::err_access_dtor_vbase)
+                << Context.getTypeDeclType(ClassDecl) << VBase->getType(),
+            Context.getTypeDeclType(ClassDecl)) ==
+        AR_accessible) {
+      CheckDerivedToBaseConversion(
+          Context.getTypeDeclType(ClassDecl), VBase->getType(),
+          diag::err_access_dtor_vbase, 0, ClassDecl->getLocation(),
+          SourceRange(), DeclarationName(), 0);
+    }
 
     MarkFunctionReferenced(Location, const_cast<CXXDestructorDecl*>(Dtor));
     DiagnoseUseOfDecl(Dtor, Location);

diff --git a/test/CXX/drs/dr0xx.cpp b/test/CXX/drs/dr0xx.cpp
index 4298960426dc593db2c09dc98c7388f70fa72950..7ff199d0b1f362820ae42a86dbafd90475714393 100644 (file)
--- a/test/CXX/drs/dr0xx.cpp
+++ b/test/CXX/drs/dr0xx.cpp
@@ -59,10 +59,13 @@ namespace dr5 { // dr5: yes
   const C c = e;
 }
 
-namespace dr7 { // dr7: no
+namespace dr7 { // dr7: yes
   class A { public: ~A(); };
-  class B : virtual private A {};
-  class C : public B {} c; // FIXME: should be rejected, ~A is inaccessible
+  class B : virtual private A {}; // expected-note 2 {{declared private here}}
+  class C : public B {} c; // expected-error 2 {{inherited virtual base class 'dr7::A' has private destructor}} \
+                           // expected-note {{implicit default constructor for 'dr7::C' first required here}} \
+                           // expected-note {{implicit default destructor for 'dr7::C' first required here}}
+  class VeryDerivedC : public B, virtual public A {} vdc;
 
   class X { ~X(); }; // expected-note {{here}}
   class Y : X { ~Y() {} }; // expected-error {{private destructor}}