IIUC [C23](https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3096.pdf#subsection.6.9.1) [does](https://www.open-std.org/jtc1/sc22/wg14/www/docs/n2510.pdf) have that C++ feature (thanks [Wikipedia](https://en.wikipedia.org/wiki/C23_(C_standard_revision)#Syntax) for the links)
Ok, finally!! But then why add the attribute for function parameters ... oh maybe a macro expansion might make it unused "eeeeek macro!!" /me jumps on chair.