Here's an example failure on the buildbot: --- /Users/buildbot/Desktop/BuildData/WebKit-BuildSlave/post-commit-powerpc-mac-os-x/build/LayoutTests/fast/leaks/003-expected.txt 2007-02-27 16:44:27.000000000 -0800 +++ layout-test-results/fast/leaks/003-actual.txt 2007-02-28 08:13:55.000000000 -0800 @@ -1,4 +1,4 @@ This test verifies that garbage collection successfully cleans up after the destruction of a frame containing a JavaScript interpreter. If the test passes, you'll see a PASS message below. -PASS: 20 garbage JS objects or fewer left uncollected after destroying a frame. +FAIL: 94 garbage JS objects left uncollected. I can't reproduce this failure on my Intel or PPC machine. I'm disabling this test for now. Hopefully we can return to it when we have some free time.