On 12.05.2025 14:09, Andrew Cooper wrote: > On 12/05/2025 12:59 pm, Jan Beulich wrote: >> On 05.05.2025 21:44, Stefano Stabellini wrote: >>> On Mon, 5 May 2025, Andrew Cooper wrote: >>>> In macros it is common to declare local variables using typeof(param) in >>>> order >>>> to ensure that side effects are only evaluated once. A consequence of >>>> this is >>>> double textural expansion of the parameter, which can get out of hand very >>>> quickly with nested macros. >>>> >>>> A GCC extension, __auto_type, is now avaialble in the new toolchain >>>> baseline >>>> and avoids the double textural expansion. >>> I think this is a good change >> +1 > > That looks like agreement. > > Now for the (new) controversial part. Since sending this, Linux has > decided to just #define auto __auto_type for C < 23, in order to start > writing C23 compatible code from now. It's more succinct, and has > better longevity. > > We might want to consider the same, although it will introduce a new > example of defining a keyword, which we'd have to call out in the > MISRA/Eclair config.
I'm not outright opposed, as I don't think we use "auto" with its original semantics, but it feels somewhat odd. Jan
