[Bug c++/63657] [4.9/5 regression] -Wunused-variable: warning supressed by virtual dtor

[petschy at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63657

--- Comment #4 from petschy at gmail dot com ---
Sorry, but this is definitely not the same issue. Bug 38958 is about returning
by value and binding to a reference. This issue is about returning a REFERENCE
and binding it to a reference. No class ctor/dtor/copy is involved, references
are just syntactic sugar on pointers: a single pointer is returned and stored
locally. This is 100% sure, since in the production code the bug appeared with
a singleton which is not constructible/destructible/copyable to the outside
world.

Please reopen the issue.