[R-SIG-Mac] Please test R 4.3.0 RC, more information below

[Simon Urbanek]

Dear Mac users,

the next major R release R 4.3.0 is coming very soon so I would like to ask you to, please, test the pre-releases from

https://mac.R-project.org

such that any possible new issues are detected *before* the release. The upcoming release will be for macOS 11 and higher only to leverage new compilers (important for modern C++ support) and libraries. As usual, there are two releases: one for the older Intel Macs (x86_64) and one for the new M1/M2 Macs (arm64) - please install the matching version.

R users can stop reading here, just test, please!

Package developers, please check the CRAN result pages for your package to make sure it passes checks. Also please note that we are now using a universal GNU Fortran compiler that works both on Intel and arm64 Macs - you can download an Apple Installer from
https://mac.r-project.org/tools/

There are two major changes for the Intel build relevant to advanced users:

a) .Platfrom$pkgType is "mac.binary.big-sur-x86_64" since we are targeting a new macOS version (this is to match arm64 which uses "mac.binary.big-sur-arm64"). It means that binaries for contributed packages in repositories live in bin/macosx/big-sur-x86_64/contrib/4.3.

b) the Intel build now matches the arm64 build such that dependent libraries are expected in /opt/R/x86_64 (to match arm64's /opt/R/arm64) to avoid conflicts with other tools. You can still add -I/usr/local/include to CPPFLAGS or -L/usr/local/lib to LDFLAGS if you want to use 3rd party libraries from /usr/local (refer to R and package documentation for details).

Finally, R will no longer sets the macos-version-min flag by default, which means R will build for the currently installed macOS version. This allows users to build packages that use the latest SDK and capabilities of the latest macOS without any changes. However, if you are distributing package binaries for use others, we strongly recommend that you set

export MACOSX_DEPLOYMENT_TARGET=11.0

when compiling binaries which will make sure that they will run on macOS 11 and higher, otherwise your binary may not be compatible.

CRAN also uses the macOS11 SDK via

export SDKROOT=/Library/Developer/CommandLineTools/SDKs/MacOSX11.sdk

However, depending on your Xcode version you may not have such SDK, so it is optional.

Cheers,
Simon