Right now, labels are emitted as part of a @footnote directive.
That results in e.g.

Note1: (@footnote{@w{(1)}
Future versions of GCC may zero-extend...
})

which is incorrect and should be rather:

Note1: (@footnote{Future versions of GCC may zero-extend...})

The CR character was added for readability of output.  But it makes the
texinfo writer a bit complicated.  This removes it from output to keep
our code simple (reducing conditions).