[PATCH] detect incompatible aliases (PR c/81854)

[Martin Sebor]

On 09/18/2017 03:44 PM, Joseph Myers wrote:
> 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.

Done in r252976.

Thanks
Martin