mangling of member template constructors

[Alex Samuel]

Folks,

Here's a mangling corner case that needs special treatment and should
be added to the spec.  If you have a member template constructor,
currently we mangle its return type (since return types of all
template functions are mangled).  Since it's a constructor, it should
have a special exemption, and not have a return type encoded.

For instance

    class K {
    public:
	template<typename T> K (T* p) {}
    };

    template K::K<int> (int* p);

should be mangled _ZN1KC2IiEEPT_ rather than _ZN1KC2IiEEvPT_ (or
something else, depending on what you consider its `return type' to
be).

Regards
Alex Samuel