The code relies on the alloc feature of the ciborium-io crate, but
does not activate it directly. Instead, the feature gets activate by
the dependence on ciborium, which does explictly rely on the alloc
feature.
The additive nature of features in Cargo means that the alloc feature
is therefore always enabled, but it's better to be clear/explicit about
what is needed from dependencies.
The code relies on the
allocfeature of theciborium-iocrate, but does not activate it directly. Instead, the feature gets activate by the dependence onciborium, which does explictly rely on theallocfeature.The additive nature of features in Cargo means that the
allocfeature is therefore always enabled, but it's better to be clear/explicit about what is needed from dependencies.