[Bug c++/59246] GCC should issue runtime error for calling pure virtual function with definition

[Bug c++/59246] GCC should issue runtime error for calling pure virtual function with definition

[boostcpp at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59246

--- Comment #1 from Ryou Ezoe <boostcpp at gmail dot com> ---
According to the de facto standard C++ ABI:
http://mentorembedded.github.io/cxx-abi/abi.html#pure-virtual

__cxa_pure_virtual will be called:
> if the user calls a non-overridden pure virtual function, which has undefined
> behavior according to the C++ Standard. 

When this abstract class Base's destructor was called,
class objects derived from Base are already destructed.

So it is non-overridden and it is also undefined behavior.

[Bug c++/59246] GCC should issue runtime error for calling pure virtual function with definition

[redi at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59246

Jonathan Wakely <redi at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2013-11-22
     Ever confirmed|0                           |1

--- Comment #2 from Jonathan Wakely <redi at gcc dot gnu.org> ---
(In reply to Ryou Ezoe from comment #0)
> // call by unqualified name is virtual function call.
> // virtual function call during destruction is undefined.

N.B. it's only undefined if the function is a pure virtual, not in general, and
you do get a warning:

pv.cc: In destructor ‘virtual Base::~Base()’:
pv.cc:14:7: warning: pure virtual ‘virtual void Base::f()’ called from
destructor [enabled by default]
     f() ;
       ^

Here's a complete testcase (you can't get a runtime error if your program can't
be run!)


struct Base
{
    virtual void f() = 0 ;
    virtual ~Base() ;
} ;

// pure virtual function with definition
void Base::f() { }

Base::~Base()
{
// call by unqualified name is virtual function call.
// virtual function call during destruction is undefined.
    f() ;
}

struct Derived : Base
{
  void f() { }
};

int main()
{
  Derived d;
}
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Subject: [Bug middle-end/57748] [4.7/4.8/4.9 Regression] ICE when expanding assignment to unaligned zero-sized array
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http://gcc.gnu.org/bugzilla/show_bug.cgi?idW748

--- Comment #48 from Paulo J. Matos <paulo@matos-sorge.com> ---
(In reply to Paulo J. Matos from comment #47)
> Would like to add that I backported the patch locally and all the testsuite
> is passing until now. The ICE I initially got is not gone as well. So I can
> confirm that as far as I know, the patch is indeed fine in 4.8.

s/not/now/.

Obviously I meant that the patch applies cleanly and works for me in 4.8.

[Bug c++/59246] GCC should issue runtime error for calling pure virtual function with definition

[boostcpp at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59246

--- Comment #3 from Ryou Ezoe <boostcpp at gmail dot com> ---
Sorry.
I should have provide a complete source code.
I thought it's more helpful to issue runtime abort even though the standard
doesn't requires it.

[Bug c++/59246] GCC should issue runtime error for calling pure virtual function with definition

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=59246

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Severity|normal                      |enhancement
   Last reconfirmed|2013-11-22 00:00:00         |2021-11-10