Thanks for the details. I noticed that gcc-toolchain and gfortran-toolchain are mismatched: the former is at version 12 while the latter is at version 10. (So

Thanks for the details. I noticed that gcc-toolchain and gfortran-toolchain are mismatched: the former is at version 12 while the latter is at version 10. (Someone must have forgotten to update gfortran when they updated gcc-toolchain.) I get no errors when using this environment: guix shell --container r-minimal r-tmb coreutils make gcc-toolchain@10 gfortran-toolchain@10 (Feel free to send future problem reports to bug-guix@gnu.org.)