[R-pkg-devel] Best practices for R package requiring Fortran 2003

[Avraham Adler]

Following the news, I've been trying to clean up my package which uses
Fortran in preparation for the changes that appear to be coming in
R-devel. The package has implicitly been relying on Fortran 2003,
since it uses iso_c_binding. In practice, is it proper that
"-std=f2003" be explicitly added to PKG_FCFLAGS (or possibPKG_FFLAGS
in 3.6.0)? Should "Fortran 2003" be listed in SystemRequirements? It
currently passes CRAN checks, but that's because all the Fortran
compilers in use have the iso_c_bindings implemented (GCC 4.5 already
had it, and it's clearly in Oracle Developer Studio 12.5).

Thank you,

Avi