lua-users home
lua-l archive

[Date Prev][Date Next][Thread Prev][Thread Next] [Date Index] [Thread Index]

On Fri, Jun 12, 2020 at 11:20 Roberto Ierusalimschy <> wrote:
The compiler only detects this instance, but Lua has had lots of
instances like that for a long time. The problem is that we have a
tagged union, and some tags don't need the union, and therefore don't
use it. In 5.4 that includes booleans, but nil is like that since
the beginning.  Whenever we copy a nil TValue, we are accessing an
uninitialized value_ field.

I figured as much, but I did not want to assume my analysis was correct. I quoted 'bug' intentionally.
Thanks for the explanation.