scoping issue in @sync

[amitmurthy]

The below scoping behavior seems a little confusing:

addprocs(1)

function foo()
    a = 3
    @sync begin 
        @spawn println(a)
    end
end

foo()

works as expected, but

@sync begin
    b = 2
    @spawn println(b)
end

fails with a exception on 2: ERROR: b not defined .

Was triggered by https://groups.google.com/d/msg/julia-users/RsX64KwJUBU/iZAwcNB_c5kJ

Maybe related: #3713

[amitmurthy]

Closed by #19594

[tkelman]

tested?