Comment 4 for bug 1308200

Fixed in the Git repository. This will be part of 1.6~alpha6 very shortly

You can see the commit message below, and you can check the diff of the fix at:

    https://anonscm.debian.org/cgit/apt/apt.git/diff/?id=3bbd328
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commit 3bbd328396745d0dd6c5585935040082a2c41e3e
Author: Julian Andres Klode <email address hidden>
Date: Tue Jan 2 22:15:50 2018 +0100

    Add rapid "happy eyeballs" connection fallback (RFC 8305)

    Try establishing connections in alternating address families in
    rapid intervals of 250 ms, adding more connections to the wait
    list until one succeeds (RFC 8305, happy eyeballs 2).

    It is important that WaitAndCheckErrors() waits until it has
    a successful connection, a time out, or all connections failed
    - otherwise the timing between tries might be wrong, and the
    final long wait might exit early because one connection failed
    without trying the others. Timing wise, this only works correctly
    on Linux, as select() counts down there. But we rely on that in
    some other places too, so this is not the time to fix that.

    Timeouts are only reported in the final long wait - the short
    inner waits are expected to time out more often, and multiple
    times, we do not want to report them.

    Closes: #668948
    LP: #1308200
    Gbp-Dch: paragraph