Bug 6966 - Repeatedly calling ShowDialog crashes Mono on OSX
Summary: Repeatedly calling ShowDialog crashes Mono on OSX
Status: NEW
Alias: None
Product: Class Libraries
Classification: Mono
Component: Windows.Forms ()
Version: unspecified
Hardware: Macintosh Mac OS
: Lowest normal
Target Milestone: Community
Assignee: Bugzilla
Depends on:
Reported: 2012-09-06 19:49 UTC by hsander
Modified: 2017-09-01 11:56 UTC (History)
3 users (show)

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

Screenshots and program illustrating bug (186.51 KB, application/pdf)
2012-09-06 19:49 UTC, hsander

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Description hsander 2012-09-06 19:49:32 UTC
Created attachment 2467 [details]
Screenshots and program illustrating bug

A very simple example (see code attached) where the default AboutBox is shown with “ShowDialog(this)” works without issues under Mono on Linux and Windows.  However, when run under OSX using “mono MonoDialogTest.exe”, artifacts start to appear when the ShowDialog function is called repeatedly (~5 times in 10 seconds).  After several more times the application crashes and Mono needs to be force quit.  Screenshots and program attached.  This bug affects other applications I've run under Mono on Mac.  Try running your favorite program under Mono on a Mac and click "File>Open" a dozen times relatively quickly.
Comment 1 Zoltan Varga 2012-09-07 14:50:07 UTC
-> winforms.
Comment 2 hsander 2012-09-23 23:33:10 UTC
This bug seems to affect EVERY application that uses winforms with mono on osx. 
I can't think of a workaround other than not to use any forms in the application.
Comment 3 me 2017-08-28 03:57:57 UTC
Bump (5 years later!).
This still seems to be a serious issue, especially when more than one modal dialog is active at the same time, or if a modal dialog is invoked from another modal dialog.