http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60775
Bug ID: 60775
Summary: Instantiates unused class template member function and
therefor reports error
Product: gcc
Version: 4.8.2
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: gunther.laure at gmail dot com
g++ 4.8.2 reports following error when compiling the example code:
abstract_class.cpp:11:13: error: cannot allocate an object of abstract type
‘IfSomethingIterator’
Derived operator--(int)
^
abstract_class.cpp:17:7: note: because the following virtual functions are
pure within ‘IfSomethingIterator’:
class IfSomethingIterator : public iterator_facade<IfSomethingIterator>
^
abstract_class.cpp:24:18: note: virtual void
IfSomethingIterator::DoIncrement()
virtual void DoIncrement() = 0;
The code successfully compiles with:
g++4.6.3
g++4.7.3
clang++ 3.3
/// example start
template <class Derived>
class iterator_facade
{
public:
Derived& operator++()
{
}
Derived operator--(int)
{
}
};
class IfSomethingIterator : public iterator_facade<IfSomethingIterator>
{
public:
virtual ~IfSomethingIterator()
{}
protected:
virtual void DoIncrement() = 0;
};
/// example end
