IntelliSense completion fails to give results in many cases -- after return/public and before a comment (works in VS)

[sean-mcmanus]

Use code

class foo { public: int jjj;};
int main()
{
    auto iii = foo{};
    return
        // no completion on this line, e.g. no main or iii suggestions
        iii
        // no completion on this line, e.g. no main or iii suggestions
        .jjj;
}

Invoke completion via Ctrl+Space on the indicated lines. There are no results from cpptools, but there should be -- it works in VS. Reproed with 1.20.5/1.21.0.

[sean-mcmanus]

There are multiple cases:

1. After return in the original example.
2. After public.
3. Before the // comments in the original example.

I'm guessing there's some sort of shared root cause.