[R-SIG-Mac] Please test R 4.0.0 pre-releases!

[Simon Urbanek]

Dear Mac users,

R 4.0.0 will be using an entirely new toolchain, entirely new build system on entirely new macOS version and hardware. Therefore I would like to ask you kindly to test the binaries from

https://mac.R-project.org

before the release as much as you can. Raising any issues after the release is too late! So please, please, test the pre-releases. Report any issues either directly to me or this mailing list.

The nightly builds are signed, but not necessarily notarized. However, the build fulfils Apple's conditions and is known to pass notarization (in fact the the package available for download today is actually notarized) so it should be a good test for the release which will be notarized and should work on Catalina.

For those that want to replicate our setup - technical details: we are now building with macOS 10.13 (High Sierra) as target (i.e. the oldest supported system), regular Apple Xcode/command line tools and GNU Fortran 8.2. R builds are running on macOS 10.15 (Catalina) with Xcode 11.4 using macOS 10.13 target. Packages are built on macOS 10.13 VMs with just Apple command line tools (this should make it easy to replicate the setup using Travis, for example). All 3rd party libraries that CRAN uses are available in http://mac.r-project.org/libs-4/

The new R build system is in
https://svn.r-project.org/R-dev-web/trunk/QA/Simon/R4
Packages build system has not changed and is in
https://svn.r-project.org/R-dev-web/trunk/QA/Simon/packages

We also plan to have a mac-builder available with similar function as the win-builder where pre-submission tests can be performed and potentially a Travis template.

Please test R pre-releases and provide feedback!

Thanks,
Simon