https://gcc.gnu.org/bugzilla/show_bug.cgi?id=90790
Bug ID: 90790
Summary: Using override on a private overridden destructor
shall produce an error
Product: gcc
Version: 10.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: zhonghao at pku dot org.cn
Target Milestone: ---
The code is as follows:
This code:
class Base
{
virtual ~Base() = default;
};
class Derived : public Base
{
~Derived() override = default;
};
My gcc is 10.0.0, and it accepts the code. clang++ rejects its with the
message:
<source>:8:2: error: deleted function '~Derived' cannot override a non-deleted
function
~Derived() override = default;
^
<source>:3:10: note: overridden virtual function is here
virtual ~Base() = default;
^
<source>:6:17: note: destructor of 'Derived' is implicitly deleted because base
class 'Base' has an inaccessible destructor
class Derived : public Base
^
<source>:8:2: warning: explicitly defaulted destructor is implicitly deleted
[-Wdefaulted-function-deleted]
~Derived() override = default;
^
<source>:6:17: note: destructor of 'Derived' is implicitly deleted because base
class 'Base' has an inaccessible destructor
class Derived : public Base
^
1 warning and 1 error generated.
Compiler returned: 1
msvc also rejects the code:
source>(9): warning C4624: 'Derived': destructor was implicitly defined as
deleted
<source>(8): error C2282: 'Derived::~Derived' cannot override 'Base::~Base'
<source>(3): note: 'Base::~Base' is not deleted
The code sample comes from https://bugs.llvm.org/show_bug.cgi?id=30844
David Blaikie makes a comments: Because the base class dtor is private, the
explicitly defaulted derived class dtor is defined as deleted (since it can't
be defined as anything else - because the base class dtor is inaccessible for
it to access, so the derived dtor can't be implemented).
His argument seems to be correct.
