From: merch-redmine@...
Date: 2019-08-14T05:51:14+00:00
Subject: [ruby-core:94338] [Ruby master Bug#11718] Constant access on `nil`

Issue #11718 has been updated by jeremyevans0 (Jeremy Evans).

File nil-const-access-11718.patch added

This bug is still present in the master branch.  Attached is a patch that fixes it.  It adds a second argument to the getconstant instruction.  It would probably be better for performance to add a separate instruction for the case where this is needed, but I'm not sure it is worth it.  With the patch:

```ruby
nil::Object
# TypeError (nil is not a class/module)
```


----------------------------------------
Bug #11718: Constant access on `nil`
https://bugs.ruby-lang.org/issues/11718#change-80737

* Author: vais (Vais Salikhov)
* Status: Open
* Priority: Normal
* Assignee: ko1 (Koichi Sasada)
* Target version: 
* ruby -v: ruby 2.2.3p173 (2015-08-18 revision 51636) [x86_64-linux]
* Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN, 2.2: UNKNOWN
----------------------------------------
It is possible to access top-level constants by doing `nil::CONSTANT`, which looks like a bug [according to Matz](https://github.com/opal/opal/issues/1197#issuecomment-158078778). Here are a couple of examples:

```
$ ruby -ve "Foo = 123; p nil::Foo"
ruby 2.2.3p173 (2015-08-18 revision 51636) [x86_64-linux]
123
```

```
$ ruby -ve "class A; Foo = 456; end; p nil::A::Foo"
ruby 2.2.3p173 (2015-08-18 revision 51636) [x86_64-linux]
456
```

Thanks!

---Files--------------------------------
nil-const-access-11718.patch (5.32 KB)


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