R for Windows 3.6.2

What's new in this version:

New features:
- runmed(x, *) gains a new option na.action determining _how_ to handle NaN or NA in x
- dotchart() gains new options ann, xaxt, frame.plot and log

Installation on a unix-alike:
- Detection of the C stack direction has been moved from run-time to configure: this is safer with LTO builds and allows the detection to be overridden - see file config.site
- Source-code changes enable installation on platforms using gcc-fno-common (the expected default for gcc 10.x)

C-level facilities:
- installTrChar (which is nowadays is wrapped by installChar) is defined in Rinternals.h. (Neither are part of the API.)

Package installation:
- Header Rconfig.h contains the value of FC_LEN_T deduced at installation which is used by the prototypes in headers R_ext/BLAS.h and R_ext/Lapack.h but to avoid extensive breakage this is only exposed when USE_FC_LEN_T is defined
- If a package's C/C++ calls to BLAS/LAPACK allow for the 'hidden' arguments used by most Fortran compilers to pass the lengths of Fortran character arguments, define USE_FC_LEN_T and include Rconfig.h (possibly _via_ R.h) before including R_ext/BLAS.h or R_ext/Lapack.h
- A package with Fortran source code and perhaps C (but not C++) sources can request for its shared object/DLL to be linked by the Fortran compiler by including a line USE_FC_TO_LINK= in src/Makevars[.win] and using $(SHLIB_OPENMP_FFLAGS) as part of PKG_LIBS
- The known reason for doing so is a package which uses Fortran (only) OpenMP on a platform where the Fortran OpenMP runtime is incompatible with the C one (e.g. gfortran 9.x with clang)

Utilities:
- R CMD check has a new option to mitigate checks leaving files/directories in /tmp. See the 'R Internals' manual - this is part of --as-cran

Windows:
- The default standard for C++ in package installation is C++11 (as it has been on other platforms where available since R 3.6.0: the default toolchain on Windows was defaulting to C++98)

Deprecated and defunct:
- Support for specifying C++98 in package installation is deprecated
- Support in R CMD config for F77, FCPIFCPLAGS, CPP, CXXCPP and CXX98 and similar is deprecated. (CPP is found from the system make and may well not be set)
- Use $CC -E and $CXX -E instead of CPP and CXXCPP

Bug fixes:
- runmed(x, *) when x contains missing values now works consistently for both algorithm="Stuetzle" and "Turlach", and no longer segfaults for "Turlach", as reported by Hilmar Berger
- apply(diag(3), 2:3, mean) now gives a helpful error message
- dgamma(x, shape, log=TRUE) now longer overflows to Inf for shape < 1 and very small x, fixing PR#17577, reported by Jonathan Rougier
- Buffer overflow in building error messages fixed. Reported by Benjamin Tremblay
- options(str = .) is correctly initialized at package utils load time, now. A consequence is that str() in scripts now is more consistent to interactive use, e.g., when displaying function(**) argument lists
- as.numeric() now gives correct error message
- Printing ls.str() no longer wrongly shows "" in rare cases
- Auto-printing S4 objects no longer duplicates the object, for faster speed and reduced memory consumption. Reported by Aaron Lun
- pchisq(, , ncp=100) no longer takes practically forever in some cases. Hence ditto for corresponding qchisq() calls
- x %% L for finite x no longer returns NaN when L is infinite, nor suffers from cancellation for large finite L, thanks to Long Qu's
Analogously, x %/% L and L %/% x suffer less from cancellation and return values corresponding to limits for large L
- grepl(NA, *) now returns logical as documented
- options(warn=1e11) is an error now, instead of later leading to C stack overflow because of infinite recursion
- R_tryCatch no longer transfers control for all conditions. Reported and patch provided by Lionel Henry in PR#17617
- format(object.size(.), digits=NULL) now works, fixing PR#17628 reported by Jonathan Carroll
- get_all_vars(f, d) now also works for cases, e.g. where d contains a matrix. Reported by Simon Wood in 2009 and patch provided by Ben Bolker in PR#13624
- Additionally, it now also works when some variables are data frames, fixing PR#14905, reported by Patrick Breheny
- barplot() could get spacings wrong if there were exactly two bars PR#15522. Patch by Michael Chirico
- power.t.test() works in more cases when returning values of n smaller than 2
- dotchart(*, pch=., groups=.) now works better. Reported by Robert and confirmed by Nic Rochette in PR#16953
- canCoerce(obj, cl) no longer assumes length(class(obj)) == 1
- plot.formula(*, subset = *) now also works in a boundary case reported by Robert Schlicht (TU Dresden)
- readBin() and writeBin() of a rawConnection() now also work inlarge cases