[Bug c++/84158] [6/7/8 Regression] missing -Wreturn-type due to incorrect handling of attributes for template specializations

[msebor at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84158
Bug 84158 depends on bug 83871, which changed state.

Bug 83871 Summary: wrong code for attribute const and pure on distinct template specializations
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83871

           What    |Removed                     |Added
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             Status|ASSIGNED                    |RESOLVED
         Resolution|---                         |FIXED