[Bug c++/43135] New: Possible bug in name resolution during template instantiation

[uwe at netbsd dot org]

I'm reporting this against my system compiler (4.1.2 on NetBSD/macppc), but I
can reproduce it using all versions from 3.4 (when two-stage name lookup was
introduced) to 4.4 - which I was able to test on a linux/amd64 machine with a
large collection of compilers installed.

The following code (minimized test case) is rejected with

$ g++ -S bug_p.cpp
bug_p.cpp: In member function 'bool Node::FooOpNode<_Op>::f() [with _Op = X]':
bug_p.cpp:63:   instantiated from here
bug_p.cpp:54: error: cannot call member function 'bool Node::test(int)' without
object

If offending call to "test" is qualified as "Node::test", compiler accepts it
happily.

Yes, I read http://gcc.gnu.org/onlinedocs/gcc/Name-lookup.html#Name-lookup


----8<--------8<----
struct X {
    int i;
};


class Node {
public:
    template <typename _Op> class OpNode;
    template <typename _Op> class FooOpNode;
    class FooNode;

    Node() {}
    virtual ~Node() {}

    bool test(int i) { return true; }

    virtual bool f() { return true; }
};


template <typename _Op>
class Node::OpNode
  : public Node
{
  public:
    typedef OpNode<_Op> OpNodeBase;

    _Op &op;

    OpNode(_Op &op) : Node(), op(op) {}

    // "test" call ok here
    virtual bool f() { return !test(op.i); }
};


template <typename _Op>
class Node::FooOpNode
  : public OpNode<_Op>
{
  public:
    typedef OpNode<_Op> OpNodeBase;
    using OpNodeBase::op;

    typedef FooOpNode<_Op> FooOpNodeBase;

    FooOpNode(_Op &op) : OpNodeBase(op) {}

    // "test" call marked as error here
    // unless qualified as Node::test()
    virtual bool f() {
        return
            // Node::
            test(op.i);
    }
};


class Node::FooNode
  : public FooOpNode<X>
{
  public:
    FooNode(X &x) : FooOpNodeBase(x) {}
};
----8<--------8<----


-- 
           Summary: Possible bug in name resolution during template
                    instantiation
           Product: gcc
           Version: 4.1.2
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: uwe at netbsd dot org
 GCC build triplet: powerpc--netbsd
  GCC host triplet: powerpc--netbsd
GCC target triplet: powerpc--netbsd


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43135