Hi,
I am trying the 64-bit VM from http://squeak.hpl.hp.com/squeak64/dist3.
Tried to file some old app and the VM crashed.  On a closer look, it
appears that every time I try to add a new class instance variable to
a class, e.g. in a regular browser, the following crash will occur:

Segmentation fault
182935061880 Object>becomeForward:
182935055456 [] in ClassBuilder>update:to:
182935054536 BlockContext>ensure:
182935054352 BlockContext>valueUnpreemptively
182935054168 ClassBuilder>update:to:
182935053800 ClassBuilder>mutate:to:
182935051744 [] in ClassBuilder>recompile:from:to:mutate:
182935051928 [] in ClassBuilder>informUserDuring:
182935053616 MVCMenuMorph>informUserAt:during:
182935051560 Utilities class>informUserDuring:
182935051376 ClassBuilder>informUserDuring:
182935051192 ClassBuilder>recompile:from:to:mutate:
182935049544 ClassBuilder>class:instanceVariableNames:unsafe:
182935049360 ClassBuilder>class:instanceVariableNames:
182935049128 Metaclass>instanceVariableNames:
182935048944 UndefinedObject>DoIt
182935043736 Compiler>evaluate:in:to:notifying:ifFail:logged:
182935043552 Compiler class>evaluate:for:notifying:logged:
182935043368 Compiler class>evaluate:notifying:logged:
182935042976 Browser>defineClass:notifying:
182935042392 Browser>contents:notifying:
182935042144 PluggableTextMorph>acceptTextInModel
182935041960 PluggableTextMorph>accept
182935041296 TextMorphForEditView>acceptContents
182935041112 TextMorphEditor>accept
182935041664 [] in ParagraphEditor>save:
182935040928 Controller>terminateAndInitializeAround:
182935040744 ParagraphEditor>save:
182935040560 ParagraphEditor>dispatchOnCharacter:with:
182935040328 TextMorphEditor>dispatchOnCharacter:with:
182935040008 ParagraphEditor>readKeyboard
182935039824 TextMorphEditor>readKeyboard
182935039416 [] in TextMorph>keyStroke:
182935039232 TextMorph>handleInteraction:fromEvent:
182935038944 TextMorphForEditView>handleInteraction:fromEvent:
182935038760 TextMorph>keyStroke:
182935038576 TextMorphForEditView>keyStroke:
182935037840 TextMorph>handleKeystroke:
182935037656 KeyboardEvent>sentTo:
182935037472 Morph>handleEvent:
182935037288 Morph>handleFocusEvent:
182935038024 [] in HandMorph>sendFocusEvent:to:clear:
182935038208 [] in PasteUpMorph>becomeActiveDuring:
182935037104 BlockContext>on:do:
182935036920 PasteUpMorph>becomeActiveDuring:
182935036472 HandMorph>sendFocusEvent:to:clear:
182935036288 HandMorph>sendEvent:focus:clear:
182935036104 HandMorph>sendKeyboardEvent:
182935035920 HandMorph>handleEvent:
182935035480 HandMorph>processEvents
182935035664 [] in WorldState>doOneCycleNowFor:
182935035296 SequenceableCollection>do:
182935035112 WorldState>handsDo:
182935034928 WorldState>doOneCycleNowFor:
182935034744 WorldState>doOneCycleFor:
182935034560 PasteUpMorph>doOneCycle
182931951848 [] in Project class>spawnNewProcess
182931952216 [] in BlockContext>newProcess

Steps to reproduce: (1) in a browser, create a new class, TEST;
(2) switch to the class side and try adding a new class instance
variable, X.  Squeak will segfault.
This is on Ubntu Linux running on an AMD64.