I got a failure on CI with tst_slotslayout:
Executing dbus-test-runner --task gdb -p --quiet -n tst_slotslayout.qml -m 500 -p --batch -p -ex -p 'set print thread-events off' -p -ex -p run -p -ex -p bt -p --return-child-result -p --args -p /tmp/buildd/ubuntu-ui-toolkit-gles-1.3.1872+16.04.20160308/tests/unit_x11/tst_components/tst_components -p -input -p tst_slotslayout.qml -p -maxwarnings -p 100 -p -o -p /tmp/buildd/ubuntu-ui-toolkit-gles-1.3.1872+16.04.20160308/tests/test_tst_slotslayout.qml.xml,xunitxml -p -o -p -,txt
Working directory: /tmp/buildd/ubuntu-ui-toolkit-gles-1.3.1872+16.04.20160308/tests/unit_x11/tst_components
DBus daemon: unix:abstract=/tmp/dbus-EJFObKuEFm,guid=d5fc837e49f55972e9b2c748571133ef
tst_slotslayout.qml: Started with PID: 28926
Undefined command: "". Try "help".
tst_slotslayout.qml: [Thread debugging using libthread_db enabled]
tst_slotslayout.qml: Using host libthread_db library "/lib/i386-linux-gnu/libthread_db.so.1".
tst_slotslayout.qml: [New Thread 0xee5f3b40 (LWP 28938)]
tst_slotslayout.qml: [New Thread 0xecd9eb40 (LWP 28939)]
tst_slotslayout.qml: ********* Start testing of components *********
tst_slotslayout.qml: Config: Using QtTest library 5.4.1, Qt 5.4.1 (i386-little_endian-ilp32 shared (dynamic) release build; by GCC 4.9.2)
tst_slotslayout.qml: PASS : components::SlotsLayout::initTestCase()
tst_slotslayout.qml: PASS : components::SlotsLayout::test_changeAttachedPropertiesInMainSlot()
tst_slotslayout.qml: PASS : components::SlotsLayout::test_changeSlotPosition()
tst_slotslayout.qml: PASS : components::SlotsLayout::test_contentPadding(Empty)
tst_slotslayout.qml: PASS : components::SlotsLayout::test_contentPadding(Labels)
tst_slotslayout.qml: PASS : components::SlotsLayout::test_contentPadding(One leading slot)
tst_slotslayout.qml: PASS : components::SlotsLayout::test_contentPadding(One trailing slot)
tst_slotslayout.qml: PASS : components::SlotsLayout::test_contentPadding(One leading, one trailing slots)
tst_slotslayout.qml: PASS : components::SlotsLayout::test_contentPadding(Two trailing)
tst_slotslayout.qml: PASS : components::SlotsLayout::test_contentPadding(One leading, two trailing slots)
tst_slotslayout.qml: PASS : components::SlotsLayout::test_contentPadding(One leading, two trailing slots with custom paddings)
tst_slotslayout.qml: PASS : components::SlotsLayout::test_customPadding(Custom padding)
tst_slotslayout.qml: INFO : components::SlotsLayout::test_defaultLabelsQmlContext() Did not receive message: "file:///tmp/buildd/ubuntu-ui-toolkit-gles-1.3.1872+16.04.20160308/tests/unit_x11/tst_components/tst_slotslayout.qml: QML Label: Cannot open: file:///test.png"
tst_slotslayout.qml: FAIL! : components::SlotsLayout::test_defaultLabelsQmlContext() Not all expected messages were received
tst_slotslayout.qml: QWARN : components::SlotsLayout::test_defaultLabelsQmlContext() file:///tmp/buildd/ubuntu-ui-toolkit-gles-1.3.1872+16.04.20160308/tests/unit_x11/tst_components/tst_slotslayout.qml: QML Label: Cannot open: file:///test.png
tst_slotslayout.qml: PASS : components::SlotsLayout::test_defaultLabelsWrappingAndElide()
tst_slotslayout.qml: PASS : components::SlotsLayout::test_defaultMainSlotHeight()
tst_slotslayout.qml: PASS : components::SlotsLayout::test_defaultSlotsAttachedProps()
tst_slotslayout.qml: PASS : components::SlotsLayout::test_fontsizeChange()
tst_slotslayout.qml: PASS : components::SlotsLayout::test_ignoreSomeChangesOnMainSlot()
tst_slotslayout.qml: PASS : components::SlotsLayout::test_implicitSize(Empty)
tst_slotslayout.qml: PASS : components::SlotsLayout::test_implicitSize(Labels)
tst_slotslayout.qml: PASS : components::SlotsLayout::test_implicitSize(One leading slot)
tst_slotslayout.qml: PASS : components::SlotsLayout::test_implicitSize(One trailing slot)
tst_slotslayout.qml: PASS : components::SlotsLayout::test_implicitSize(One leading, one trailing slots)
tst_slotslayout.qml: PASS : components::SlotsLayout::test_implicitSize(Two trailing)
tst_slotslayout.qml: PASS : components::SlotsLayout::test_implicitSize(One leading, two trailing slots)
tst_slotslayout.qml: PASS : components::SlotsLayout::test_implicitSize(One leading, two trailing slots with custom paddings)
tst_slotslayout.qml: PASS : components::SlotsLayout::test_layout(Empty)
tst_slotslayout.qml: PASS : components::SlotsLayout::test_layout(Labels)
tst_slotslayout.qml: PASS : components::SlotsLayout::test_layout(One leading slot)
tst_slotslayout.qml: PASS : components::SlotsLayout::test_layout(One trailing slot)
tst_slotslayout.qml: PASS : components::SlotsLayout::test_layout(One leading, one trailing slots)
tst_slotslayout.qml: PASS : components::SlotsLayout::test_layout(Two trailing)
tst_slotslayout.qml: PASS : components::SlotsLayout::test_layout(One leading, two trailing slots)
tst_slotslayout.qml: PASS : components::SlotsLayout::test_layout(One leading, two trailing slots with custom paddings)
tst_slotslayout.qml: PASS : components::SlotsLayout::test_mainSlotSize()
tst_slotslayout.qml: PASS : components::SlotsLayout::test_multilineLabelsPositioning()
tst_slotslayout.qml: PASS : components::SlotsLayout::test_nullSizeSlots()
tst_slotslayout.qml: PASS : components::SlotsLayout::test_overrideVerticalPositioning()
tst_slotslayout.qml: PASS : components::SlotsLayout::test_relativePositioning(Relative positioning 1)
tst_slotslayout.qml: PASS : components::SlotsLayout::test_relativePositioning(Relative positioning 2)
tst_slotslayout.qml: PASS : components::SlotsLayout::test_relayoutAfterChangingSlotsSize()
tst_slotslayout.qml: PASS : components::SlotsLayout::test_slotVisibilityChange()
tst_slotslayout.qml: PASS : components::SlotsLayout::test_warningOnAttemptToChangeListItemLayoutMainSlot()
tst_slotslayout.qml: PASS : components::SlotsLayout::cleanupTestCase()
tst_slotslayout.qml: Totals: 43 passed, 1 failed, 0 skipped, 0 blacklisted
tst_slotslayout.qml: ********* Finished testing of components *********
tst_slotslayout.qml: [Thread 0xecd9eb40 (LWP 28939) exited]
tst_slotslayout.qml: [Thread 0xee5f3b40 (LWP 28938) exited]
tst_slotslayout.qml: [Inferior 1 (process 28929) exited with code 01]
No stack.
tst_slotslayout.qml: Exited with status 256
tst_slotslayout.qml: Shutting down
DBus daemon: Shutdown
tst_slotslayout.qml exited with 0
I did not see it before, so I assume the test is flaky. The full CI run where it failed is here https://jenkins.ubuntu.com/ubuntu-sdk/job/ubuntu-ui-toolkit-ci-i386-gles-stable/457/console
Status changed to 'Confirmed' because the bug affects multiple users.