This is an unofficial snapshot of the ISO/IEC JTC1 SC22 WG21 Core Issues List revision 118e. See http://www.open-std.org/jtc1/sc22/wg21/ for the official list.

2025-11-05

85. Redeclaration of member class

In 6.5.6 [basic.lookup.elab] paragraph 3, there is the example

    struct Base {
        // ...
        struct Data { /* ... */ };  // Defines nested Data
        struct Data;                // OK: Redeclares nested Data
    };

Proposed resolution (10/00): Remove the line

        struct Data;                // OK: Redeclares nested Data

See also Core issue 36 and Core issue 56.