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Non-API entry points ‘Rf_acopy_string’ and ‘Rf_lazy_duplicate’ have been added to those reported by ‘R CMD check’.
When ‘"POSIXlt"’ date-time objects are ‘NA’-padded from subsetting or increasing ‘length’ in the ‘`[`’ or ‘`length<-`’ methods, the ‘"balanced"’ attribute is set to ‘NA’, now; noted in PR#18681, thanks to Mikael Jagan.