On Mon, Jan 19, 2026 at 03:57:08PM +0100, Josef Melcr wrote: > +<!-- introduced in 0eac9cfee8cb0b21de866a04d5d59685ab35208f --> > + > +<p> > +Since GCC 16, <code>-Wunused-but-set-*</code> warning options no longer > +consider preincrements and postincrements as uses, which may lead to > +compilation failures when using <code>-Werror</code>. > +</p>
That IMHO doesn't describe the change correctly (the change wasn't by -Wall/-W default only about pre/post increments but also about var @= expr) and more importantly, doesn't tell users what they should do. The PR44677 change simply changed the -Wunused-but-set-* warnings to have multiple levels and the old options as well as defaults implied by -Wall or -W default to the =3 level, while the GCC 15 and earlier provided level was equivalent to the =1 level. Usually porting_to.html shows some code snippet, describes what changed and suggests what to do. I think this porting_to.html entry should refer to https://gcc.gnu.org/onlinedocs/gcc/Warning-Options.html#index-Wunused-but-set-variable_003d and maybe https://gcc.gnu.org/PR44677 , show the code example mentioned in the documentation and suggest users that they can either remove the unused but set variables/parameters to fix the warnings, or make them used e.g. through (void) casts, or if some project generally likes the previous behavior, lower the level to -Wunused-but-set-variable=1 or similar. Jakub
