Does anyone else see this? It's a weird problem since the update in 
question only removes code and as a consequence there shouldn't be any 
attempt to create new compiled method trailers during installation. Have 
you by any chance some other package installed that hooks into 
SystemChangeNotifier and does strange things upon method removal?


Cheers,
   - Andreas

Randal L. Schwartz wrote:
> MessageNotUnderstood: CompiledMethodTrailer class>>trailerClass
> 22 December 2009 8:09:25.698 am
> 
> VM: Mac OS - a SmalltalkImage
> Image: Squeak3.10.2 [latest update: #8507]
> 
> SecurityManager state:
> Restricted: false
> FileAccess: true
> SocketAccess: true
> Working Dir /Users/merlyn/Smalltalk/Squeak3.0/Squeak3.10.2-Trunk-090912
> Trusted Dir /foobar/tooBar/forSqueak/bogus
> Untrusted Dir /Users/merlyn/Library/Preferences/Squeak/Internet/My Squeak
> 
> CompiledMethodTrailer class(Object)>>doesNotUnderstand: #trailerClass
>                       Receiver: CompiledMethodTrailer
>                       Arguments and temporary variables: 
> <<error during printing>
>         Receiver's instance variables: 
>                    superclass:         Object
>                                        methodDict:      a MethodDictionary(#clear->(CompiledMethodTrailer>>#clear "a Compil...etc...
>                                                         format:                                                   140
>                                                                                                                   instanceVariables:  #('data' 'encodedData' 'kind' 'size' 'method')
>                                                                                                                                       organization:          ('initialize-release' clear initialize method:)
> ('creating a meth...etc...
>              subclasses:        nil
>                                 name:   #CompiledMethodTrailer
>                                         classPool:      a Dictionary()
>                                                         sharedPools:    nil
>                                                                         environment:    Smalltalk "a SystemDictionary with lots of globals"
>                                                                                         category:    #'Kernel-Methods'
>                                                                                                      traitComposition:  nil
>                                                                                                                         localSelectors:  nil
> 
> CompiledMethodTrailer class>>new
>                       Receiver: CompiledMethodTrailer
>                       Arguments and temporary variables: 
> <<error during printing>
>         Receiver's instance variables: 
>                    superclass:         Object
>                                        methodDict:      a MethodDictionary(#clear->(CompiledMethodTrailer>>#clear "a Compil...etc...
>                                                         format:                                                   140
>                                                                                                                   instanceVariables:  #('data' 'encodedData' 'kind' 'size' 'method')
>                                                                                                                                       organization:          ('initialize-release' clear initialize method:)
> ('creating a meth...etc...
>              subclasses:        nil
>                                 name:   #CompiledMethodTrailer
>                                         classPool:      a Dictionary()
>                                                         sharedPools:    nil
>                                                                         environment:    Smalltalk "a SystemDictionary with lots of globals"
>                                                                                         category:    #'Kernel-Methods'
>                                                                                                      traitComposition:  nil
>                                                                                                                         localSelectors:  nil
> 
> CompiledMethod>>trailer
>         Receiver: (CompiledMethodTrailer class>>#trailerClass "a CompiledMethod(3360)")
>         Arguments and temporary variables: 
> <<error during printing>
>         Receiver's instance variables: 
> (CompiledMethodTrailer class>>#trailerClass "a CompiledMethod(3360)")
> CompiledMethod>>sourcePointer
>         Receiver: (CompiledMethodTrailer class>>#trailerClass "a CompiledMethod(3360)")
>         Arguments and temporary variables: 
> <<error during printing>
>         Receiver's instance variables: 
> (CompiledMethodTrailer class>>#trailerClass "a CompiledMethod(3360)")
> 
>