Rollup merge of #36754 - tmiasko:getaddrinfo-errors, r=alexcrichton

When getaddrinfo returns EAI_SYSTEM retrieve actual error from errno.

Fixes issue #36546. This change also updates libc to earliest version
that includes EAI_SYSTEM constant.

Previously, in cases where `EAI_SYSTEM` has been returned from getaddrinfo, the
resulting `io::Error` would be broadly described as "System error":

    Error { repr: Custom(Custom { kind: Other, error: StringError("failed to lookup address information: System error") }) }

After change a more detailed error is crated based on particular value of
errno, for example:

    Error { repr: Os { code: 64, message: "Machine is not on the network" } }

The only downside is that the prefix "failed to lookup address information" is
no longer included in the error message.

0 files changed, 0 insertions, 0 deletions