Andreas Raab uploaded a new version of System to project The Trunk:
http://source.squeak.org/trunk/System-cbc.146.mcz

==================== Summary ====================

Name: System-cbc.146
Author: cbc
Time: 9 September 2009, 11:14:36 am
UUID: 34e15b6a-dd90-f446-8142-a1cc416881a5
Ancestors: System-ar.145

Fixed MessageTally>>spyEvery:on: to work with BlockClosure and BlockContext (by removing hard reference to BlockClosure).

=============== Diff against System-ar.145 ===============

Item was changed:
  ----- Method: MessageTally>>spyEvery:on: (in category 'initialize-release') -----
  spyEvery: millisecs on: aBlock 
  	"Create a spy and spy on the given block at the specified rate."
  	"Spy only on the active process (in which aBlock is run)"
  
  	| myDelay startTime time0 observedProcess |
+ 	aBlock isBlock
- 	(aBlock isMemberOf: BlockContext)
  		ifFalse: [self error: 'spy needs a block here'].
  	self class: aBlock receiver class method: aBlock method.
  		"set up the probe"
  	observedProcess _ Processor activeProcess.
  	myDelay := Delay forMilliseconds: millisecs.
  	time0 := Time millisecondClockValue.
  	gcStats := SmalltalkImage current getVMParameters.
  	Timer := [
  		[true] whileTrue: [
  			startTime := Time millisecondClockValue.
  			myDelay wait.
  			self tally: Processor preemptedProcess suspendedContext
  				in: (ShowProcesses ifTrue: [
  					observedProcess == Processor preemptedProcess ifTrue: [observedProcess] ifFalse: [nil]])
  				"tally can be > 1 if ran a long primitive"
  				by: (Time millisecondClockValue - startTime) // millisecs].
  		nil] newProcess.
  	Timer priority: Processor timingPriority-1.
  		"activate the probe and evaluate the block"
  	Timer resume.
  	^ aBlock ensure: [
  		"Collect gc statistics"
  		SmalltalkImage current getVMParameters keysAndValuesDo: [ :idx :gcVal | 
  			gcStats at: idx put: (gcVal - (gcStats at: idx))].
  		"cancel the probe and return the value"
  		Timer terminate.
  		time := Time millisecondClockValue - time0]!