Title
Lookup of mem-initializer-ids
Status
cd6
Section
11.9.3 [class.base.init]
Submitter
Richard Corden

Created on 2006-12-05.00:00:00 last changed 20 months ago

Messages

Date: 2009-10-15.00:00:00

Notes from the October, 2009 meeting:

The eventual resolution of this issue should take into account the template parameter scope introduced by the resolution of issue 481.

Date: 2020-11-15.00:00:00

[Accepted at the November, 2020 meeting as part of paper P1787R6 and moved to DR at the February, 2021 meeting.]

In an example like,

    struct Y {};

    template <typename T>
    struct X : public virtual Y { };

    template <typename T>
    class A : public X<T> {
      template <typename S>
      A (S)
        : S ()
      {
      }
    };

    template A<int>::A (Y);

Should S be found? (S is a dependent name, so if it resolves to a base class type in the instantiated template, it should satisfy the requirements.) All the compilers I tried allowed this example, but 11.9.3 [class.base.init] paragraph 2 says,

Names in a mem-initializer-id are looked up in the scope of the constructor's class and, if not found in that scope, are looked up in the scope containing the constructor's definition.

The name S is not declared in those scopes.

Mike Miller: Here's another example that is accepted by most/all compilers but not by the current wording:

    namespace N {
      struct B { B(int); };
      typedef B typedef_B;
      struct D: B {
        D();
      };
    }

    N::D::D(): typedef_B(0) { }

Except for the fact that the constructor function parameter names are ignored (see paragraph 7), what the compilers seem to be doing is essentially ordinary unqualified name lookup.

History
Date User Action Args
2022-08-19 07:54:33adminsetstatus: drwp -> cd6
2021-02-24 00:00:00adminsetstatus: accepted -> drwp
2020-12-15 00:00:00adminsetstatus: open -> accepted
2009-11-08 00:00:00adminsetmessages: + msg2407
2006-12-05 00:00:00admincreate