The last release of proc-macro-error was 3.5 years ago. It appears that the author of proc-macro-error has been AFK from their GitLab for around 2.5 years, which in particular means that proc-macro-error is not being updated to use syn 2 (see e.g. https://gitlab.com/CreepySkeleton/proc-macro-error/-/merge_requests/35).
From the discussions around proc-macro-error there appear to be two maintained alternatives:
The last release of
proc-macro-error
was 3.5 years ago. It appears that the author ofproc-macro-error
has been AFK from their GitLab for around 2.5 years, which in particular means thatproc-macro-error
is not being updated to usesyn 2
(see e.g. https://gitlab.com/CreepySkeleton/proc-macro-error/-/merge_requests/35).From the discussions around
proc-macro-error
there appear to be two maintained alternatives:proc-macro2-diagnostics
manyhow