[ruby-core:66429] [ruby-trunk - Bug #10537] Repeated creation and garbage collection of WeakRef instances against a single object leaks memory

Issue #10537 has been updated by Alex Boyd.


Data point: tacking a `printf` onto the end of `define_final0` in `gc.c` reveals that a new finalizer is being added to `a` for each WeakRef. I expect those are what's hogging memory.

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Bug #10537: Repeated creation and garbage collection of WeakRef instances against a single object leaks memory
https://bugs.ruby-lang.org/issues/10537#change-50061

* Author: Alex Boyd
* Status: Open
* Priority: Normal
* Assignee: 
* Category: lib
* Target version: 
* ruby -v: ruby 2.2.0dev (2014-11-24 trunk 48552) [x86_64-darwin14]
* Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN
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~~~
require 'weakref'
a = Object.new
1_000_000.times do
  WeakRef.new a
end
GC.start
~~~

The above results in Ruby consuming ~150 MB of RAM, all of which can only be freed by dropping `a`. This should not be the case - an object being weakly referenced should not itself hold a reference to the WeakRef (or any associated data) pointing at it.



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