If the range expression in a range based for loop returns a temporary,
its lifetime is extended until the end of the loop. The same can't be said
about temporaries created within the range expression. In our case,
*t->get_sstables_including_compacted_undeleted() returns a reference to a
const sstable_list, but the t->get_sstables_including_compacted_undeleted()
is a temporary lw_shared_ptr, so its lifetime may not be prolonged until the
end of the loop, and it may be the sole owner of the referenced sstable_list,
so the referenced sstable_list may be already deleted inside the loop too.
Fix by creating a local copy of the lw_shared_ptr, and get reference from it
in the loop.
Fixes#7605
Signed-off-by: Wojciech Mitros <wojciech.mitros@scylladb.com>
48153a1e2c