[Bug c++/106051] -Wmismatched-tags gives false positive warning when "class C" is "using namespace"d into a namespace with another "class C" declaration

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106051

Jonathan Wakely <redi at gcc dot gnu.org> changed:

           What    |Removed                     |Added
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           Keywords|                            |rejects-valid
                 CC|                            |msebor at gcc dot gnu.org

--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Confirmed. The -Wmismatched-tags warnings has always caused this incorrect
error since it was added in r279480

I don't think it qualifies as a regression, because using -Wmismatched-tags was
an error before that commit anyway, because the warning didn't exist at all.