Davis Vaughan and I were looking into the `-Wstrict-prototypes` warnings for C code that were recently added to the R-devel checks. We did a little research and found that these warnings are intended to catch old-style definitions and declarations that were deprecated a long time ago. This includes:
1. Unspecified types like `void fn(x, y);` 2. Unspecified parameter lists like `void fn();`. We also found: - That only unspecified types (case 1) will become defunct. For unspecified parameter lists (case 2), it was announced recently that the C standard committee has decided to simply change the meaning to "no arguments" in C23. This aligns with what most people think it means, and is what C++ does. See item 13 of page 130 in the C23 working draft at https://open-std.org/JTC1/SC22/WG14/www/docs/n3054.pdf. - The new `-Wdeprecated-non-prototype` option for clang-15 does not warn for empty parameter lists, allowing for a smooth transition that allows this widespread usage. Since the no arguments case is both incredibly common and will become fully legal C syntax in a close future, it seems it might not be worth it to require all packages to update their code to an intermediary form that reads less well, is not as intuitive to most people (and so might crop up back in further updates), and will become standard in the future anyway. Perhaps a good course of action would be: - Using `-Wno-strict-prototypes` to disable the stringent checks. - Enabling the new `-Wdeprecated-non-prototype` in clang to catch old-style definitions and declarations. This way CRAN would be able to catch deprecated syntax while allowing the soon-to-be-legal syntax of empty parameter lists. We hope that this would mean less code churn on CRAN, which means less work for the CRAN maintainers as well as for the maintainers of CRAN packages. Best, Lionel & Davis ______________________________________________ R-package-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-package-devel
