Concept-check bug ?

[Jonathan Wakely]

Hi y'all,

    #define _GLIBCXX_CONCEPT_CHECKS
    #include <vector>

    struct A {
        std::vector<A> v;
    };

This produces concept-check errors because A is incomplete at the point
of declaring v.

Is this code really illegal, or just a flaw in the concept-checks ?

This causes failures in Boost if concept-checks are enabled, because of
a similar construct.

jon