[Bug libstdc++/96063] mismatched-tags warnings in stdlib headers

[ian.s.mcinerney at ieee dot org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96063

--- Comment #6 from Ian McInerney <ian.s.mcinerney at ieee dot org> ---
They are showing up when I don't have -Wsystem-headers passed in on the command
line. Compiling the attached test program with `g++ -Wmismatched-tags main.cpp`
shows the warnings. All that is doing is including basically all public library
headers.