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unlink() is now able to remove broken symbolic links on Unix-alikes.
R CMD SHLIB now calls the makefiles with target 'all' on all platforms, not just on Windows: this is only relevant when a Makevars[.win] is used that contains targets (not in general recommended): for backwards compatibility the first target should be named 'all'.
The compiled loess() code hads been updated to the current version of dloess from Netlib. This includes patches from Ben Tyner which correct some errors when degree = 0 and hence solve PR#13570.