Issue #8345 has been updated by charliesome (Charlie Somerville). The same happens with Proc#curry too: =begin def proc end ->{}.curry =end ---------------------------------------- Bug #8345: Method#to_proc assumes lambda returns a Proc https://bugs.ruby-lang.org/issues/8345#change-39035 Author: charliesome (Charlie Somerville) Status: Open Priority: Normal Assignee: charliesome (Charlie Somerville) Category: Target version: ruby -v: ruby 2.1.0dev (2013-04-29 trunk 40512) [x86_64-darwin11.4.0] Backport: 1.9.3: UNKNOWN, 2.0.0: UNKNOWN =begin Method#to_proc calls #lambda and assumes the return value is a Proc by passing it to GetProcPtr. If #lambda is overridden this can cause segfaults: def lambda end method(:puts).to_proc # segfault =end -- http://bugs.ruby-lang.org/