Issue #10623 has been updated by Nobuyoshi Nakada.


I think a function can tell no keys from deleting `nil` value, like `hash_delete` in your patch, is necessary.

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Bug #10623: rb_hash_delete() can return Qundef in 2.2-rc1
https://bugs.ruby-lang.org/issues/10623#change-50524

* Author: Aman Gupta
* Status: Open
* Priority: Normal
* Assignee: 
* Category: 
* Target version: current: 2.2.0
* ruby -v: ruby 2.2.0dev [x86_64-darwin14]
* Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN
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The behavior of rb_hash_delete() has changed from 2.1. Before, it would always return Qnil or VALUE. Now it can also return Qundef, which is breaking the posix-spawn gem's usage:

https://github.com/rtomayko/posix-spawn/blob/master/ext/posix-spawn.c#L242-L258

It also appears RTEST(Qundef) returns true, which causes a segfault in posix-spawn gem here:

https://github.com/rtomayko/posix-spawn/blob/master/ext/posix-spawn.c#L425

I think we should revert back to original behavior before 2.2.0 is released.



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