http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47709
Summary: is_heap(standard iterator) becomes ambiguous in C++0x mode Product: gcc Version: 4.6.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: libstdc++ AssignedTo: unassig...@gcc.gnu.org ReportedBy: jyass...@gcc.gnu.org $ cat test.cc #include <ext/algorithm> #include <vector> void foo() { std::vector<int> v; is_heap(v.begin(), v.end()); } $ g++-4.6svn -c test.cc $ g++-4.6svn -c test.cc -std=c++0x test.cc: In function ‘void foo()’: test.cc:6:29: error: call of overloaded ‘is_heap(std::vector<int>::iterator, std::vector<int>::iterator)’ is ambiguous test.cc:6:29: note: candidates are: include/c++/4.6.0/ext/algorithm:436:5: note: bool __gnu_cxx::is_heap(_RandomAccessIterator, _RandomAccessIterator) [with _RandomAccessIterator = __gnu_cxx::__normal_iterator<int*, std::vector<int> >] include/c++/4.6.0/bits/stl_heap.h:560:72: note: bool std::is_heap(_RAIter, _RAIter) [with _RAIter = __gnu_cxx::__normal_iterator<int*, std::vector<int> >] I believe the fix is to "using std::is_heap" into __gnu_cxx in C++0x mode rather than redefining it there. Another possible fix would be to move __normal_iterator out of __gnu_cxx to avoid ADL finding that is_heap, but that wouldn't help people who have already "using __gnu_cxx::is_heap" into their global namespaces.