gcc has a function attribute [[gnu::warn_unused_result]] that is "stronger" than [[nodiscard]] in that it cannot be suppressed by cast to void (unfortunately, clang claims to support it but didn't get that part of the memo, causing confusion and frustration); that attribute has been used for some time on the interface of the GNU libc. GNU continue to use it in preference to [[nodiscard]] precisely because (when using the GNU C and C++ compilers) it cannot be suppressed by cast to void.

Do you have an opinion on whether that implementation-specific attribute's warning should also be suppressed by [[discard]]?

Thanks, Ed