<div dir="ltr">When <font face="monospace">-Wused-but-marked-unused</font> was added 10 (!) years ago, <a href="http://lists.llvm.org/pipermail/cfe-commits/Week-of-Mon-20101018/035732.html">John pointed out</a> that this breaks idiomatic usage of <font face="monospace">__attribute__((unused))</font>. It did then, and it still does today; searching for <a href="https://github.com/inviwo/inviwo/blob/master/ext/warn/include/warn/ignore/used-but-marked-unused">mentions</a> <a href="https://github.com/ruslo/leathers/blob/master/Source/leathers/used-but-marked-unused">of</a> <a href="https://lists.gnu.org/archive/html/bug-gnulib/2019-08/msg00083.html">this</a> <a href="https://chromium.googlesource.com/infra/goma/client/+/master/build/generate_known_warnings_list.go#371">flag</a> <a href="https://gitlab.freedesktop.org/xrdesktop/gulkan/commit/2bdb5bab7c9a33a77eb3b7f7ac94772ef91ffcfa">reveals</a> <a href="https://opensource.apple.com/source/xnu/xnu-4570.41.2/makedefs/MakeInc.def.auto.html">that</a> by and large the only time people mention it is to turn it off or complain about it.<div><br></div><div>At the time it was added, John also <a href="http://lists.llvm.org/pipermail/cfe-commits/Week-of-Mon-20101018/035742.html">implicitly asked</a> why anyone would ever want this warning, and that question went unanswered at the time. So I'm going to ask it again: does anyone want this warning (even though it breaks the <a href="https://gcc.gnu.org/onlinedocs/gcc/Common-Function-Attributes.html#index-unused-function-attribute">documented intent</a> (note: "<i>possibly</i> unused") of <font face="monospace">__attribute__((unused))</font> for <font face="monospace">-Werror</font> builds) -- and if so, why?</div><div><br></div><div><div>If we can't establish a rationale for this warning existing, I suggest we remove it.</div></div><div><br></div><div>Thoughts?</div></div>