On 2018-10-27 14:06, Miguel Ojeda wrote: > Hi Rasmus, > > On Sat, Oct 27, 2018 at 1:24 AM Rasmus Villemoes > <li...@rasmusvillemoes.dk> wrote: >> >> +/* >> + * Optional > > I did quick check and gcc >= 4.1, clang >= 3.0, icc >= 13 compilers > seem to support it (or at least recognize it, even if they just ignore > it), so we do not need to make it optional, no? Did I miss some case?
No idea. I think I didn't really know what was meant by required/optional. E.g. something like __aligned must be supported and honoured for correctness, while format_arg is just about getting some diagnostics, and assume_aligned just allows for certain optimizations, so it doesn't really matter whether every single compiler understands them. It does seem that both icc and clang understand format_arg and issues warnings when the template doesn't match the varargs, so in that sense we can make it "required", though it seems a little backwards to define required in terms of what the current range of compilers support. Rasmus