Your bug report

#67477: Automake warns that $(?D) is a non-POSIX variable name

which was filed against the automake package, has been closed.

The explanation is attached below, along with your original report.
If you require more details, please reply to 67477@debbugs.gnu.org.

-- 
67477: https://debbugs.gnu.org/cgi/bugreport.cgi?bug=67477
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