On Tue, 29 Nov 2016, Ralph Giles wrote: > On 2016-11-29 1:17 AM, Santiago Vila wrote: > > > I wonder, however, why two lines like this in /etc/hosts > > > > 127.0.0.1 localhost > > 127.0.0.1 localhost ip6-localhost ip6-loopback > > > > should make rustc build to fail at all. > > The test was added in https://github.com/rust-lang/rust/pull/34700 to > guard against regression of a bug where std::net::lookup_host() > incorrectly returned multiple copies of each address. > > The /etc/hosts database format certainly allows duplicate entries. It > seems that glibc, at least, does not merge those, but instead returns > the listed n-to-m mappings directly through the `struct hostent` > returned by both gethostbyaddr() and gethostbyname(). > > Even if it doesn't violate any spec, I agree with Luca that this is a > misconfiguration. The normal application of multiple address entries > is for service failover. Any client connecting to localhost with your > configuration will immediately retry connection failures, which is a > waste of resources. [...]
Ok, but the duplicate localhost entry, as I explained, is not something which I deliberately chose, it's the result of using schroot on a machine not having IPv6 enabled. Unless IPv6 has become mandatory for autobuilders (I hope not), this is still a bug (i.e. definitely *not* wishlist) in schroot, for converting ::1 into 127.0.0.1 and causing the FTBFS problem. I'll reassign it. Thanks.
