[Bug c++/64596] Friendship not recognized and template param deduction error

[daniel.kruegler at googlemail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64596

Daniel Krügler <daniel.kruegler at googlemail dot com> changed:

           What    |Removed                     |Added
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--- Comment #2 from Daniel Krügler <daniel.kruegler at googlemail dot com> ---
1) Your friend declaration in line 15 is invalid, because you cannot declare an
alias template as friend. I suggest to change that to

    template<typename, bool>
    friend class Txn;

instead.

2) The compiler is right: The language says that the partial specialization in
line 80 can never be deduced. Your code is equivalent to attempting to
specialize:

template<typename E, bool R>
struct Glue<typename StrB<E>::template Txn<R>, int>

where this becomes more obvious.