Announcement: R-devel "sonoma-arm64" Mac builds

On 14/12/2025, at 12:03 PM, Jeroen Ooms <jeroenooms at gmail.com> wrote:

On Sat, Dec 13, 2025 at 10:39?PM Simon Urbanek
<simon.urbanek at r-project.org> wrote:

On 14/12/2025, at 11:24 AM, Jeroen Ooms <jeroenooms at gmail.com> wrote:

On Fri, Dec 12, 2025 at 3:20?AM Simon Urbanek
<simon.urbanek at r-project.org> wrote:

The goal is to remove the existing big-sur-arm64 R-devel binaries in favor of the sonoma-arm64 R-devel build. Since we are still far away from the R-devel release, all this is considered experimental and may change in the future (possibly Fortran upgrade is in the cards), but given that this is not a minor change, I want to give others the opportunity to test the new setup and comment as appropriate.

Thanks. Some quick observations:

The x86_64 build of r-devel on https://mac.r-project.org/ is almost 2 months old?

Should be fixed now.

On arm64, using the latest R-devel-arm64.pkg on a machine with macOS 15 and Xcode_16.2, I get the following error for all packages with compiled C code:

error: invalid value 'gnu23' in '-std=gnu23'
note: use 'c2x' for 'Working Draft for ISO C2x' standard
note: use 'gnu2x' for 'Working Draft for ISO C2x with GNU extensions' standard

That is expected, you'll need at least Xcode 16.3 since 16.2 is LLVM 17 while 16.3 is LLVM 19 which, as has been discussed at length, was a big breaking jump. As noted, what is actually used is Xcode 26.x so that would be recommended (albeit not required).

The reason we were using 16.2 is that newer xcode versions still do
not seem to work with the libomp.dylib included with base R. Has
libomp.dylib been updated yet?

Yes, it matches the Xcode - as noted:

On 12/12/2025, at 4:25 PM, Simon Urbanek <simon.urbanek at R-project.org> wrote:

On 12 Dec 2025, at 08:26, Jeroen Ooms <jeroenooms at gmail.com> wrote:
[...]
Also It would be interesting to know which version of libomp.dylib will be included with R-macos 4.6 :)

LLVM 19.1.5 to match current Xcode 26.x, i.e. https://mac.r-project.org/openmp/openmp-19.1.5-darwin20-Release.tar.gz

Again, that was the point of the tool upgrade :).

According to otool it is the same version as before?

otool shows the API version as declared by Intel OpenMP, but the LLVM team has never updated it despite breaking changes, unfortunately :/. It's really annoying since it means it is very hard to determine which LLVM it came from - even internally all of the them declare the same version 5.0.20140926 and API version 5.0.201611 - both being almost 10 years out of date.