Updated mangling specs

[Martin von Loewis]

> Consider the following example:
> 
> 	// file 1:
> 	template<int I> int f(A<I+1>::X) { return 1; }
> 	template void f<1>(A<2>::X);
> 
> 	// file 2:
> 	template<int I> int f(A<2*I>::X) { return 2; }
> 	template void f<1>(A<2>::X);

Maybe I'm having problem with the English language here. The phrase is

# Two expressions involving template parameters that are not
# equivalent are functionally equivalent if, for any given set of
# template arguments, the evaluation of the expression results in the
# same value.

Does that mean: They are functionally equivalent if there exists a set
of arguments so they evaluate to the same value?

Or does that mean: They are functionally equivalent if they evaluate
to the same value for every set of template arguments?

I'd interpret that as meaning the former: I+1 and 2*I are functionally
eqivalent, because there is an I (I=1) for which the value is the
same.

As a result, your example would ill-formed: It defines two templates
which are functionally equivalent but not equivalent.

Of course, if it meant the latter, your example would be
well-formed. I'm not sure what kinds of heroic efforts the distinction
of functionally equivalent and equivalent would save you, though.

Regards,
Martin

P.S. Under my interpretation, the example in 14.5.5.1/5 (which you had
quoted) would be ill-formed, as the instantiations would be
indistinguishable for I=J=K=L=0. I'd claim this as a defect, though.