net: builtin DNS stub resolver behaves case sensitive and gives "no such host"

[gopherbot]

by russmackdev:

What does 'go version' print?
go version go1.4rc2 linux/amd64

What steps reproduce the problem?
If possible, include a link to a program on play.golang.org.

1. http://play.golang.org/p/0kQQT1Qz40

What happened?
Some DNS responses are capitalised eg:
&{{www4.L.GOOGLE.com. 1 1 153 4} 2915202115}
The comparison with lowercase name fails resulting in "no such host".

What should have happened instead?
The comparison should not fail, and the host should be acknowledged as found.

Please provide any additional information below.
Patch attached.

Attachments:

1. dnsclient.go.patch (166 bytes)

[ianlancetaylor]

For the record, the string comparison in question is in net/dnsclient.go in the function answer.

[mikioh]

fyi: http://tools.ietf.org/html/rfc4343