Random crashes in Windows upon use of (:~) with Event

[sukhmel]

1. When (:~) is used with set ... [on command ...], program crashes, and prints Segmentation fault/access violation in generated code message;
2. Crashes occur frequently, but not always;
3. In case when tested with only one object, crash never happens immediately after start;
4. Upon use of (:=), everything works fine;
5. Sample code is provided.

This issue was fully decribed in HeinrichApfelmus/reactive-banana#62.

• when line with (:=), marked with a comment, is used, everything is perfectly fine
• when (:~) is used, random crashes occur frequently.

> import Control.Monad (replicateM, mapM_)
> import Graphics.UI.WX

> main = start $ do
>        pad     <- frame [ ]                     
>        buttons <- replicateM 2
>                 $ button pad  []

>        mapM_ (flip set [on command := return ()]) buttons -- OK
>        mapM_ (flip set [on command :~ const (return ())]) buttons

[swamp-agr]

Cannot reproduce bug with this environment:

• wxWidgets: 2.9.5
• ghc: 7.6.3
• MinGW (for wxWidgets build): 5.1.16
• MinGW (for wx build) - default for Haskell Platform.
• MSYS: 1.0
• wx: 0.90.1.1