[R-pkg-devel] Status of -mmacosx-version-min

[Dirk Eddelbuettel]

Last month, I had asked about the setting '-mmacosx-version-min' here.  The
setting can be used to specify what macOS version one builds for. It is,
oddly enough, not mentioned in Writing R Extension but for both r-release and
r-devel the R Administration manual states

   • Current CRAN macOS distributions are targeted at Big Sur so it is
     wise to ensure that the compilers generate code that will run on
     Big Sur or later.  With the recommended compilers we can use
          CC="clang -mmacosx-version-min=11.0"
          CXX="clang++ -mmacosx-version-min=11.0"
          FC="/opt//gfortran/bin/gfortran -mmacosx-version-min=11.0"
     or set the environment variable
          export MACOSX_DEPLOYMENT_TARGET=11.0

which is clear enough. (There is also an example in the R Internals manual
still showing the old (and deprecated ?) value of 10.13.)  It is also stated
at the top of mac.r-project.org.  But it is still in a somewhat confusing
contradiction to the matrix of tests machines, described e.g. at

   https://cran.r-project.org/web/checks/check_flavors.html

which still has r-oldrel-macos-x86_64 with 10.13.

I found this confusing, and pressed the CRAN macOS maintainer to clarify but
apparently did so in an insuffciently convincing manner. (There was a word
about it being emailed to r-sig-mac which is a list I am not on as I don't
have a macOS machine.) So in case anybody else wonders, my hope is that the
above is of help. At my day job, we will now switch to 11.0 to take advantage
of some more recent C++ features.

Dirk

-- 
dirk.eddelbuettel.com | @eddelbuettel | edd using debian.org