@krlmlr This 9375cfa is not really portable, from what it looks:
---> Building R-duckdb
xinstall: mkdir /opt/local/var/macports/build/_opt_PPCSnowLeopardPorts_R_R-duckdb/R-duckdb/work/build
Executing: cd "/opt/local/var/macports/build/_opt_PPCSnowLeopardPorts_R_R-duckdb/R-duckdb/work/duckdb" && /opt/local/bin/R CMD INSTALL . --library=/opt/local/var/macports/build/_opt_PPCSnowLeopardPorts_R_R-duckdb/R-duckdb/work/build --install-tests
* installing *source* package ‘duckdb’ ...
file ‘src/Makevars’ has the wrong MD5 checksum
** using staged installation
++ dirname ./configure
+ cd ./src
+ '[' -f '' ']'
+ cp include/to-tar.mk Makevars.duckdb
+ '[' -f duckdb.tar.xz ']'
+ tar xJf duckdb.tar.xz
tar: invalid option -- J
Try `tar --help' or `tar --usage' for more information.
ERROR: configuration failed for package ‘duckdb’
This is not a big deal, since patching this to use specifically gnutar fixes the issue, but perhaps worth at least either having a check or a note in README?