[PATCH v3 00/16] stop using variadic argument pack extension

[David Marchand]

On Tue, Feb 27, 2024 at 7:15 PM Tyler Retzlaff
<roretzla at linux.microsoft.com> wrote:
>
> On Mon, Feb 26, 2024 at 12:54:36PM -0800, Stephen Hemminger wrote:
> > On Mon, 26 Feb 2024 12:19:30 -0800
> > Tyler Retzlaff <roretzla at linux.microsoft.com> wrote:
> >
> > > RTE_LOG_LINE cannot be augmented with a prefix format and arguments
> > > without the user of RTE_LOG_LINE using the args... and ## args compiler
> > > extension to conditionally remove trailing comma when the macro receives
> > > only a single argument.
> > >
> > > Provide a new/similar macro RTE_LOG_LINE_PREFIX that accepts the prefix
> > > format and arguments as separate parameters allowing them to be expanded
> > > at the correct locations inside of RTE_FMT() allowing the rest of the
> > > non-prefix format string and arguments to be collapsed to the argument
> > > pack which can be directly forwarded with __VA_ARGS__ avoiding the need
> > > for conditional comma removal.
> > >
> > > I've done my best to manually check expansions (preprocessed) and compiled
> > > printf of the logs to validate correct output.
> > >
> > > note: due to drastic change in series i have not carried any series acks
> > >       forward.
> >
> > The changes look good, you might want to add release note, update coding
> > style doc, and/or update checkpatch to discourage re-introduction.
>
> re-introduction should be protected by the CI. i know checkpatch would
> be better but i couldn't think of a good way to match an arbitrarily
> named pack ... reliably where it could potentially cause noise.

What about a simple:

+       # forbid use of variadic argument pack extension in macros
+       awk -v FOLDERS="lib drivers app examples" \
+               -v
EXPRESSIONS='#[[:space:]]*define.*[^(,[:space:]]\\.\\.\\.[[:space:]]*)'
\
+               -v RET_ON_FAIL=1 \
+               -v MESSAGE='Do not use variadic argument pack in macros' \
+               -f $(dirname $(readlink -f $0))/check-forbidden-tokens.awk \
+               "$1" || res=1
+


-- 
David Marchand