7.1.1/5 "The extern specifier can be applied only to the names of
objects and functions"

8.5.3/3 Mentions "where the extern specifier is explicitly used" in
normative text, and gives non-normative example "extern int& r2; //OK".

I have always thought a reference isn't an object: an object is a region
of storage, and a reference need not occupy any storage.

On the other hand an 'extern' reference seems to be able to solve real
problems, e.g. it seems it can solve a problem with the badly designed
WTL library from Microsoft where a global variable to be declared by the
client code is referred to by name from the WTL template code, and one
wants to use a derived type not yet known when including those headers.

Comeau Online 4.3.3, Visual C++ 7.1 and MinGW g++ 3.4.4 all accept
'extern' references:

  extern int& r;
  int x;
  int& r = x;
  int main() {}

I suggest fixing the immediate problem by changing the wording of
7.1.1/5 to

  7.1.1/5 proposed resolution:
  "The extern specifier can be applied only to the names of objects,
  functions and references"

Then there's possibly also a need for clarifying whether a reference is
an object (as I see it, that it isn't).

--
A: Because it messes up the order in which people normally read text.
Q: Why is it such a bad thing?
A: Top-posting.
Q: What is the most annoying thing on usenet and in e-mail?

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Alf P. Steinbach wrote:
> 7.1.1/5 "The extern specifier can be applied only to the names of
> objects and functions"

Humoristically, in 8.3.2/1, a non-normative note states "a reference can
be thought of as a name of an object."

> 8.5.3/3 Mentions "where the extern specifier is explicitly used" in
> normative text, and gives non-normative example "extern int& r2; //OK".

8.3.2/4 explictly mentions the possibility that a reference declaration
can contain an extern specifier.

> I have always thought a reference isn't an object: an object is a region
> of storage, and a reference need not occupy any storage.

To be precise "It is unspecified whether or not a reference requires
storage" (8.3.2/3). That means a reference can require storage in some
cases and not require it in other cases.

> Then there's possibly also a need for clarifying whether a reference is
> an object (as I see it, that it isn't).

According to 1.8/1 "an object is a region of storage." So, as soon as a
reference is used in a way that requires storage to be allocated, it
*is* an object. Declaring the reference as extern is just one such use.

Just my opinion,

Ganesh

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