Auto merge of rust-lang#23267 - alexcrichton:issue-20012, r=aturon

This reverts commit aec67c2.

Closes rust-lang#20012

This is temporarily rebased on rust-lang#23245 as it would otherwise conflict, the last commit is the only one relevant to this PR though.

1.0.0-alpha.2 release

1.0.0-alpha release

0.12.0 release

0.11.0 release

0.10 release

0.9 release

0.8 release

0.7 release

0.6 release