And there is a build error on jenkins:

https://ci.inria.fr/pharo/view/4.0-Analysis/job/Pharo-4.0-Issue-Tracker-Image/lastFailedBuild/console

...

==== Startup Error: MessageNotUnderstood: receiver of "-" is nil
UndefinedObject(Object)>>doesNotUnderstand: #-
DelayMicrosecondScheduler>>adjust:resumptionTimeOldBase:newBase:
DelayMicrosecondScheduler>>saveResumptionTimes
DelayMicrosecondScheduler(DelayScheduler)>>shutDown
Delay class>>shutDown
Delay class(Behavior)>>shutDown:

...

Maybe this failing build helps finding the cause.

2015-03-11 16:58 GMT+01:00 Sven Van Caekenberghe <sven@stfx.eu>:

Ouch, that would be bad.

I just saw it too on the image that I saved yesterday.

Now I retried with a fresh image and it works.

Maybe the image needs to have a certain 'age' ?

> On 11 Mar 2015, at 16:47, Christophe Demarey <christophe.demarey@inria.fr> wrote:
>
> I think there is a problem with this update.
> After saving and exiting the image, I was not able to reuse it. I got this error: Startup Error: Error: Trying to activate Delay twice
>
> See attached log for more details.

> <PharoDebug.log>
>
> Le 10 mars 2015 �� 16:31, GitHub a ��crit :

>
>>�� Branch: refs/heads/4.0
>>�� Home:�� https://github.com/pharo-project/pharo-core
>>�� Commit: bea5e5edece36093f82ab3a8854b61377dfbd0a1
>>�� https://github.com/pharo-project/pharo-core/commit/bea5e5edece36093f82ab3a8854b61377dfbd0a1
>>�� Author: Jenkins Build Server <board@pharo-project.org>
>>�� Date:�� 2015-03-10 (Tue, 10 Mar 2015)
>>
>>�� Changed paths:
>>�� M Kernel.package/Delay.class/README.md
>>�� R Kernel.package/Delay.class/class/enable new code/newCodeEnabled.st
>>�� A Kernel.package/Delay.class/class/settings/delaySchedulerClass.st
>>�� A Kernel.package/Delay.class/class/settings/delaySchedulerClass_.st
>>�� A Kernel.package/Delay.class/class/settings/systemSettingOn_.st
>>�� M Kernel.package/Delay.class/definition.st
>>�� R Kernel.package/Delay.class/instance/enable new code/newCodeEnabled.st
>>�� A Kernel.package/Delay.class/instance/printing/millisecondsToGo.st
>>�� M Kernel.package/Delay.class/instance/printing/printOn_.st
>>�� A Kernel.package/Delay.class/instance/private - scheduler/schedulerBeingWaitedOn.st
>>�� A Kernel.package/Delay.class/instance/private - scheduler/schedulerBeingWaitedOn_.st
>>�� A Kernel.package/Delay.class/instance/private - scheduler/schedulerResumptionTime.st
>>�� A Kernel.package/Delay.class/instance/private - scheduler/schedulerResumptionTime_.st
>>�� A Kernel.package/Delay.class/instance/private - scheduler/schedulerSignalWaitingProcess.st
>>�� A Kernel.package/Delay.class/instance/private - scheduler/scheduler_resumptionTime_.st
>>�� M Kernel.package/Delay.class/instance/private/setDelay_.st
>>�� M Kernel.package/Delay.class/instance/private/setDelay_forSemaphore_.st
>>�� M Kernel.package/Delay.class/instance/public/delayDuration.st
>>�� A Kernel.package/Delay.class/instance/public/millisecondDelayDuration.st
>>�� A Kernel.package/DelayMicrosecondScheduler.class/README.md
>>�� A Kernel.package/DelayMicrosecondScheduler.class/definition.st
>>�� A Kernel.package/DelayMicrosecondScheduler.class/instance/low priority processes/schedule_.st
>>�� A Kernel.package/DelayMicrosecondScheduler.class/instance/primitives/primSignal_atUTCMicroseconds_.st
>>�� A Kernel.package/DelayMicrosecondScheduler.class/instance/printing/millisecondsUntilResumptionTime_.st
>>�� A Kernel.package/DelayMicrosecondScheduler.class/instance/snapshotting/adjust_resumptionTimeOldBase_newBase_.st
>>�� A Kernel.package/DelayMicrosecondScheduler.class/instance/snapshotting/restoreResumptionTimes.st
>>�� A Kernel.package/DelayMicrosecondScheduler.class/instance/snapshotting/saveResumptionTimes.st
>>�� A Kernel.package/DelayMicrosecondScheduler.class/instance/snapshotting/startUp.st
>>�� A Kernel.package/DelayMicrosecondScheduler.class/instance/timer process/handleTimerEvent_.st
>>�� A Kernel.package/DelayMicrosecondScheduler.class/instance/timer process/runTimerEventLoop.st
>>�� A Kernel.package/DelayMicrosecondScheduler.class/instance/timer process/scheduleDelay_.st
>>�� A Kernel.package/DelayMicrosecondScheduler.class/instance/timer process/startTimerEventLoop.st
>>�� A Kernel.package/DelayMicrosecondScheduler.class/instance/timer process/stopTimerEventLoop.st
>>�� A Kernel.package/DelayMicrosecondScheduler.class/instance/timer process/unscheduleDelay_.st
>>�� A Kernel.package/DelayMillisecondScheduler.class/README.md
>>�� A Kernel.package/DelayMillisecondScheduler.class/definition.st
>>�� A Kernel.package/DelayMillisecondScheduler.class/instance/low priority processes/schedule_.st
>>�� A Kernel.package/DelayMillisecondScheduler.class/instance/primitives/primSignal_atMilliseconds_.st
>>�� A Kernel.package/DelayMillisecondScheduler.class/instance/printing/millisecondsUntilResumptionTime_.st
>>�� A Kernel.package/DelayMillisecondScheduler.class/instance/snapshotting/adjust_resumptionTimeOldBase_newBase_.st
>>�� A Kernel.package/DelayMillisecondScheduler.class/instance/snapshotting/restoreResumptionTimes.st
>>�� A Kernel.package/DelayMillisecondScheduler.class/instance/snapshotting/saveResumptionTimes.st
>>�� A Kernel.package/DelayMillisecondScheduler.class/instance/timer process/handleTimerEvent_.st
>>�� A Kernel.package/DelayMillisecondScheduler.class/instance/timer process/runTimerEventLoop.st
>>�� A Kernel.package/DelayMillisecondScheduler.class/instance/timer process/scheduleDelay_.st
>>�� A Kernel.package/DelayMillisecondScheduler.class/instance/timer process/startTimerEventLoop.st
>>�� A Kernel.package/DelayMillisecondScheduler.class/instance/timer process/stopTimerEventLoop.st
>>�� A Kernel.package/DelayMillisecondScheduler.class/instance/timer process/unscheduleDelay_.st
>>�� M Kernel.package/DelayScheduler.class/README.md
>>�� M Kernel.package/DelayScheduler.class/instance/class initialization/initialize.st
>>�� A Kernel.package/DelayScheduler.class/instance/printing/millisecondsUntilResumptionTime_.st
>>�� M Kernel.package/DelayScheduler.class/instance/testing/nextWakeUpTime.st
>>�� M Kernel.package/DelayScheduler.class/instance/timer process/stopTimerEventLoop.st
>>�� A Kernel.package/DelayWaitTimeout.class/instance/signaling/schedulerSignalWaitingProcess.st
>>�� A Kernel.package/Duration.class/instance/converting/asMicroseconds.st
>>�� A Kernel.package/MonitorDelay.class/instance/private/schedulerSignalWaitingProcess.st
>>�� A KernelTests.package/DelayMicrosecondSchedulerTest.class/README.md
>>�� A KernelTests.package/DelayMicrosecondSchedulerTest.class/definition.st
>>�� A KernelTests.package/DelayMicrosecondSchedulerTest.class/instance/running/tearDown.st
>>�� A KernelTests.package/DelayMicrosecondSchedulerTest.class/instance/support/busyWaitMilliseconds_.st
>>�� A KernelTests.package/DelayMicrosecondSchedulerTest.class/instance/tests/testDurationLessThanMaxTicks.st
>>�� A KernelTests.package/DelayMicrosecondSchedulerTest.class/instance/tests/testDurationMoreThanMaxTicks.st
>>�� A KernelTests.package/DelayMicrosecondSchedulerTest.class/instance/tests/testForMilliseconds.st
>>�� A KernelTests.package/DelayMicrosecondSchedulerTest.class/instance/tests/testForSeconds.st
>>�� A KernelTests.package/DelayMicrosecondSchedulerTest.class/instance/tests/testMillisecondsToGo.st
>>�� A KernelTests.package/DelayMicrosecondSchedulerTest.class/instance/tests/testTestInterferenceWithSystemTimingSemaphore.st
>>�� A KernelTests.package/DelayMillisecondSchedulerTest.class/README.md
>>�� A KernelTests.package/DelayMillisecondSchedulerTest.class/definition.st
>>�� A KernelTests.package/DelayMillisecondSchedulerTest.class/instance/running/tearDown.st
>>�� A KernelTests.package/DelayMillisecondSchedulerTest.class/instance/support/busyWaitMilliseconds_.st
>>�� A KernelTests.package/DelayMillisecondSchedulerTest.class/instance/tests/testDurationLessThanMaxTicks.st
>>�� A KernelTests.package/DelayMillisecondSchedulerTest.class/instance/tests/testDurationMoreThanMaxTicks.st
>>�� A KernelTests.package/DelayMillisecondSchedulerTest.class/instance/tests/testForMilliseconds.st
>>�� A KernelTests.package/DelayMillisecondSchedulerTest.class/instance/tests/testForSeconds.st
>>�� A KernelTests.package/DelayMillisecondSchedulerTest.class/instance/tests/testMillisecondsToGo.st
>>�� A KernelTests.package/DelayMillisecondSchedulerTest.class/instance/tests/testTestInterferenceWithSystemTimingSemaphore.st
>>�� R KernelTests.package/DelaySchedulerTest.class/README.md
>>�� R KernelTests.package/DelaySchedulerTest.class/definition.st
>>�� R KernelTests.package/DelaySchedulerTest.class/instance/running/tearDown.st
>>�� R KernelTests.package/DelaySchedulerTest.class/instance/tests/testMaxTickLessThanDuration.st
>>�� R KernelTests.package/DelaySchedulerTest.class/instance/tests/testMaxTickMoreThanDuration.st
>>�� R KernelTests.package/DelaySchedulerTest.class/instance/tests/testTestInterferenceWithSystemTimingSemaphore.st
>>�� R ScriptLoader40.package/ScriptLoader.class/instance/pharo - scripts/script547.st
>>�� A ScriptLoader40.package/ScriptLoader.class/instance/pharo - scripts/script548.st
>>�� R ScriptLoader40.package/ScriptLoader.class/instance/pharo - updates/update40547.st
>>�� A ScriptLoader40.package/ScriptLoader.class/instance/pharo - updates/update40548.st
>>�� M ScriptLoader40.package/ScriptLoader.class/instance/public/commentForCurrentUpdate.st
>>
>>�� Log Message:
>>�� -----------
>>�� 40548
>> 14353 Delay refactoring (part 2) - change from milliseconds to microseconds
>>�� https://pharo.fogbugz.com/f/cases/14353
>>
>> http://files.pharo.org/image/40/40548.zip
>>
>>
>