Table 9 ("simple-type-specifiers and the types they specify") describes how simple-type-specifiers are mapped into types, but it is missing an entry for decltype(auto). Presumably this should say something like "placeholder for the type of the initializer (7.1.6.4)".

We also have a conflict between 7.1.6.2/2 and 7.1.6.4/1. The former says that only auto is "a placeholder for a type to be deduced", whereas the latter says that both "are used to designate a placeholder type that will be replaced later by deduction from an initializer". decltype(auto) does not perform deduction, so this seems wrong.

One possible, but broader, change:

1. Change 7.1.6.2/4 to define "the declared type of an expression e" instead of "the type denoted by decltype(e)".
2. Change Table 9 to specify that decltype(e) gives "the declared type of e".
3. Extend Table 9 to specify that decltype(auto) gives "the declared type of the initializer, as described in 7.1.6.4".
4. Fix up 7.1.6.4 to match.