Injected class name compiler discrepancy

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It appears that clang is wrong in this case. The relevant exception I was looking for is in [class.qual]/2:

2 In a lookup in which function names are not ignored and the nested-name-specifier nominates a class C:

  • (2.1)
    if the name specified after the nested-name-specifier, when looked up in C, is the injected-class-name of C, or

  • […]

the name is instead considered to name the constructor of class C.

The standard has a near-equivalent (non-normative, obviously) example:

struct A { A(); };
struct B: public A { B(); };

A::A() { }
B::B() { }

B::A ba;// object of type A
A::A a;// error, A::A is not a type name
struct A::A a2;// object of type A

However, clang actually issues a correct diagnostic in this case:

error: qualified reference to 'A' is a constructor name rather than a type wherever a constructor can be declared

Perhaps clang interprets the line In a lookup in which function names are not ignored as In a lookup in which a constructor declaration is valid, but that doesn’t seem to be a correct interpretation.

There is an existing bug for this in the clang bugzilla.

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