On Mon, 18 Sep 2017, Martin Sebor wrote:
It's meant as an escape hatch. It allows declaring compatibility
symbols, for example by the libstdc++ _GLIBCXX_3_4_SYMVER macro
defined in libstdc++-v3/src/c++98/compatibility.cc. The macro is
used to declare compatibility functions of all sorts of incompatible
types. The originally posted patch had libstdc++ disable the warning
for the file with the symbols but Jonathan preferred this solution.
It could perhaps be tightened up to detect some of the cases on your
list but I'm not sure it's worth the effort and added complexity.
Let me know if you feel differently (or have a different suggestion),
otherwise I will go ahead and commit the patch as is.
Please add a comment explaining this reasoning and commit the patch.