From: Erik Pilkington <erik.pilkington@gmail.com>
Date: Tue, 8 Jan 2019 00:21:05 +0000 (+0000)
Subject: Split -Wdelete-non-virtual-dtor into -Wdelete-abstract-non-virtual-dtor
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=2b01328de2b9738cf847a27b227eceac8ac5bcf6;p=clang

Split -Wdelete-non-virtual-dtor into -Wdelete-abstract-non-virtual-dtor

-Wdelete-non-virtual-dtor previously controlled two diagnostics: 1)
calling a non-virtual dtor from an abstract class, and 2) calling a
non-virtual dtor from a polymorphic class. 1) is a lot more severe
than 2), since 1) is a guaranteed crash, but 2) is just "code smell".
Previously, projects compiled with -Wall -Wno-delete-non-virtual-dtor,
which is somewhat reasonable, silently crashed on 1).

rdar://40380564

Differential revision: https://reviews.llvm.org/D56405

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@350585 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/include/clang/Basic/DiagnosticGroups.td b/include/clang/Basic/DiagnosticGroups.td
index 6ba6c19a28..52bd87d79a 100644
--- a/include/clang/Basic/DiagnosticGroups.td
+++ b/include/clang/Basic/DiagnosticGroups.td
@@ -105,6 +105,8 @@ def MissingNoEscape : DiagGroup<"missing-noescape">;
 
 def DeleteIncomplete : DiagGroup<"delete-incomplete">;
 def DeleteNonVirtualDtor : DiagGroup<"delete-non-virtual-dtor">;
+def DeleteAbstractNonVirtualDtor : DiagGroup<"delete-abstract-non-virtual-dtor",
+                                             [DeleteNonVirtualDtor]>;
 def AbstractFinalClass : DiagGroup<"abstract-final-class">;
 
 def CXX11CompatDeprecatedWritableStr :
diff --git a/include/clang/Basic/DiagnosticSemaKinds.td b/include/clang/Basic/DiagnosticSemaKinds.td
index c54fbc8b4c..d6c5ccffd8 100644
--- a/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/include/clang/Basic/DiagnosticSemaKinds.td
@@ -6460,7 +6460,7 @@ def note_delete_non_virtual : Note<
   "qualify call to silence this warning">;
 def warn_delete_abstract_non_virtual_dtor : Warning<
   "%select{delete|destructor}0 called on %1 that is abstract but has "
-  "non-virtual destructor">, InGroup<DeleteNonVirtualDtor>, ShowInSystemHeader;
+  "non-virtual destructor">, InGroup<DeleteAbstractNonVirtualDtor>, ShowInSystemHeader;
 def warn_overloaded_virtual : Warning<
   "%q0 hides overloaded virtual %select{function|functions}1">,
   InGroup<OverloadedVirtual>, DefaultIgnore;
diff --git a/test/SemaCXX/non-virtual-dtors.cpp b/test/SemaCXX/non-virtual-dtors.cpp
new file mode 100644
index 0000000000..230b899a7f
--- /dev/null
+++ b/test/SemaCXX/non-virtual-dtors.cpp
@@ -0,0 +1,32 @@
+// RUN: %clang_cc1 %s -verify -DDIAG1
+// RUN: %clang_cc1 %s -verify -DDIAG1 -DDIAG2 -Wdelete-non-virtual-dtor
+// RUN: %clang_cc1 %s -verify -DDIAG1         -Wmost -Wno-delete-non-virtual-dtor
+// RUN: %clang_cc1 %s -verify                 -Wmost -Wno-delete-abstract-non-virtual-dtor
+
+#ifndef DIAG1
+#ifndef DIAG2
+// expected-no-diagnostics
+#endif
+#endif
+
+struct S1 {
+  ~S1() {}
+  virtual void abs() = 0;
+};
+
+void f1(S1 *s1) { delete s1; }
+#ifdef DIAG1
+// expected-warning@-2 {{delete called on 'S1' that is abstract but has non-virtual destructor}}
+#endif
+
+struct Base {
+  virtual void abs() = 0;
+};
+struct S2 : Base {
+  ~S2() {}
+  void abs() {}
+};
+void f2(S2 *s2) { delete s2; }
+#ifdef DIAG2
+// expected-warning@-2 {{delete called on non-final 'S2' that has virtual functions but non-virtual destructor}}
+#endif