zwaldowski/BlocksKit — pull request #58 by cysp (2012-01-11 11:48:28+00:00)
Title: Copy-autorelease block IMPs

In some circumstances imp_implementationWithBlock deadlocks without doing this.

I found a reference to this workaround online, it's pretty cargo-culty but it solved the problem for me.

Interestingly, the potential for deadlocking is mentioned in [a testcase in the runtime](http://www.opensource.apple.com/source/objc4/objc4-493.9/test/blocksAsImps.m) so it seems that the bug has been fixed.