Re: LSan curiosity in t1300

> And it is complaining that we've leaked "key". But as you can see, we
> always free it. The problem is that for this particular invocation we
> die("missing environment variable name"), so of course we don't make it
> to the free(). Normally this is OK, though. The "key" variable is still
> on the stack, so the leak-checker should realize that it's still
> reachable.
>
> But if you run this in a debugger, you'll find that under -O2 the "key"
> variable has been optimized out! So LSan is producing the wrong result
> due to the optimization. It doesn't know that "key" is conceptually
> still reachable.

> Maybe this is a known problem, but it was certainly surprising to me.
> I'm not sure if we should do anything about it or not. It doesn't seem
> to trigger in CI, even though I don't see us taking any steps there to
> use -O0 or similar. So we can perhaps ignore it for now, and this
> message can serve as a warning. But if we think LSan isn't reliable
> under higher optimizations, we could perhaps teach the Makefile to
> prefer -O0 when it sees SANITIZE=leak.