Hi. I may have discovered a bug in the PharoVM (stable and latest), which may have been around for at least two years (I had a very similiar situation about two years ago with Fuel). I have a test that fails when a particular method contains â3 timesRepeat: [ Smalltalk garbageCollect ]â. In order to be sure that itâ not the #timesRepeat message thatâs causing the crash, I replaced that with multiple âSmalltalk garbageCollectâ sends. The test Iâm talking about ObsoleteTest>>testFixObsoleteSharedPools. To make the test crash the VM, simply add a couple of garbageCollects at the end of SmalltalkImage>>fixObsoleteSharedPools. I tried to come up with a little script to demonstrate the issue but I can only reproduce the problem with Nautilus (which makes me suspect that the problem is related to Nautilus). Steps to reproduce: 1. get a fresh image and the latest vm: curl get.pharo.org/40+vmLastest <http://get.pharo.org/40+vmLastest> | bash && ./pharo-ui Pharo.image 2. open the class browser and navigate to SmalltalkImage>>fixObsoleteSharedPools 3. Append ten âself garbageCollectâ statements to the method. 4. navigate to ObsoleteTest>>testFixObsoleteSharedPools and click on the test runner icon to the left of the method name. I can reproduce this with the Mac VM (OS X 10.10) as well as with the linux VM (Ubuntu 12.04.1). Iâve opened an issue for this: https://pharo.fogbugz.com/f/cases/14478/Reproducible-VM-crash-with-excessive... <https://pharo.fogbugz.com/f/cases/14478/Reproducible-VM-crash-with-excessive...> Cheers, Max