Bug 6176 - Control.Dispose() Doesn't Protect Against Cycles
Summary: Control.Dispose() Doesn't Protect Against Cycles
Status: NEW
Alias: None
Product: Class Libraries
Classification: Mono
Component: Windows.Forms ()
Version: unspecified
Hardware: All All
: Lowest normal
Target Milestone: Community
Assignee: Bugzilla
Depends on:
Reported: 2012-07-18 10:10 UTC by Ryan Rastedt
Modified: 2017-09-01 11:56 UTC (History)
1 user (show)

Tags: mono-community
Is this bug a regression?: ---
Last known good build:

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Description Ryan Rastedt 2012-07-18 10:10:15 UTC
The mono implementation of Control.Dispose() sets the is_disposing flag to true but never references it in Dispose or turns it off.  Contrast this to the way the MS .NET Control.Dispose() is implemented, where the isdisposing state flag is checked at the start of the method and immediately returns out if it is disposing already, thus breaking any loop. 

This can result in endless cycles leading to a stack overflow in applications that do not experience such cycles on the MS CLR.

Mono's implementation also doesn't turn the flag off after disposal is complete, though that is unrelated to this issue.