qmltest::transparentForPositioner() failed on OS X 10.11

~/qt/qt5-build/qtdeclarative/tests/auto/qmltest$ make check
/Users/liangqi/qt/qt5-build/qtdeclarative/tests/auto/qmltest/target_wrapper.sh  ./tst_qmltest 
********* Start testing of qmltest *********
Config: Using QtTest library 5.6.1, Qt 5.6.1 (x86_64-little_endian-lp64 shared (dynamic) debug build; by Clang 7.3.0 (clang-703.0.31) (Apple))
...
PASS   : qmltest::transparentForPositioner::initTestCase()
FAIL!  : qmltest::transparentForPositioner::test_endresult() 'verify()' returned FALSE. ()
   Loc: [/Users/liangqi/qt/qt5/qtdeclarative/tests/auto/qmltest/item/tst_layerInPositioner.qml(51)]
PASS   : qmltest::transparentForPositioner::cleanupTestCase()
...
********* Finished testing of qmltest *********