[Bug other/86153] [9 regression] test case g++.dg/pr83239.C fails starting with r261585

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86153

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

           What    |Removed                     |Added
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                 CC|                            |msebor at gcc dot gnu.org

--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> ---
It seems unfortunate that _M_default_append is no longer inlined, but the
function was incorrect and had to be changed.

I don't know enough about the failing test to know what can or should be done
to fix it.