data.table fails to load on R-4.6-x86_64

On Mon, 16 Mar 2026 13:23:59 +0100

unable to load shared object
'/Library/Frameworks/R.framework/Versions/4.6-x86_64/Resources/library/data.table/libs/data_table.so':
dlopen(/Library/Frameworks/R.framework/Versions/4.6-x86_64/Resources/library/data.table/libs/data_table.so,
0x0006): Symbol not found: _IS_GROWABLE

That's strange, data.table is supposed to use IS_GROWABLE only on old
enough R where it needs the new APIs backported (testing both
R_Version() and the SVN revision). 'llvm-otool-14 -Vt data_table.so'
shows calls to IS_GROWABLE() & TRUELENGTH(), and also data.table's own
backports of R_resizeVector() & R_maxLength() & friends being present
inside the package dynamic library.

I would expect something like this to happen only if
data.table_1.18.2.1.tgz (January 2026) was built using R-devel prior to
r89077 (November 2025). Are the build logs of 4.6 binaries for
big-sur-x86_64 available anywhere?

Best regards,
Ivan