Extern ref from method defined outside its namespace

Clang Frontend
1

Here's a case where Clang and GCC both do the same thing but I don't see
why it is correct.

2

But, adding the "extern" declaration causes Clang to treat "k2" as
a reference to "aaa::k2" rather than "::k2". I think that's wrong.

There is no aaa:k2 in the above example, have you included an incomplete test?

Cheers,
Rafael

3

But, adding the "extern" declaration causes Clang to treat "k2" as
a reference to "aaa::k2" rather than "::k2". I think that's wrong.

There is no aaa:k2 in the above example, have you included an incomplete test?

Yes, that is the complete test. Clang generates an external reference to
"aaa::k2" which then causes the link to fail.
--paulr

4

Within an out-of-line declaration, the enclosing namespace is the
original namespace of the entity, not the lexical namespace.

C++11 [namespace.def]p6:
  The enclosing namespaces of a declaration are those namespaces in
  which the declaration lexically appears, except for a redeclaration of a
  namespace member outside its original namespace (e.g., a definition
  as specified in 7.3.1.2). Such a redeclaration has the same enclosing
  namespaces as the original declaration.

John.

5

Within an out-of-line declaration, the enclosing namespace is the
original namespace of the entity, not the lexical namespace.

C++11 [namespace.def]p6:
  The enclosing namespaces of a declaration are those namespaces in
  which the declaration lexically appears, except for a redeclaration of a
  namespace member outside its original namespace (e.g., a definition
  as specified in 7.3.1.2). Such a redeclaration has the same enclosing
  namespaces as the original declaration.

John.

Okay, so the method definition actually does implicitly reopen the
namespace scope. Thanks for pointing out where that's specified!
--paulr