[Bug c++/81597] returns link to temporary value

[glisse at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81597

--- Comment #3 from Marc Glisse <glisse at gcc dot gnu.org> ---
-Werror=return-local-addr
(we cannot reject those programs by default, if the caller ignores what the
function returns, the program may be valid)