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Various macros can be set to override the default behaviour of ‘configure’ when detecting OpenMP: see file ‘config.site’.
When operating in a non-UTF-8 multibyte locale (e.g. an East Asian locale on Windows), ‘grep()’ and related functions did not handle UTF-8 strings properly. (PR#16264)
‘read.dcf()’ sometimes misread lines longer than 8191 characters. (Reported by Hervé Pagès with a patch.)