FTBFS on amd64 due to uninitialized values in unit-tests

The unity-voice fails in the wily test-rebuild [1] due to the unit tests failing:

1/1 Test #1: unit-tests .......................***Failed 1.74 sec
[==========] Running 4 tests from 1 test case.
[----------] Global test environment set-up.
[----------] 4 tests from TestPronounceDict
[ RUN ] TestPronounceDict.HashesInDictionary
==6554== Conditional jump or move depends on uninitialised value(s)
==6554== at 0x516ADDC: qDetectCpuFeatures() (in /usr/lib/x86_64-linux-gnu/libQt5Core.so.5.4.2)
==6554== by 0x514487C: qHash(QString const&, unsigned int) (in /usr/lib/x86_64-linux-gnu/libQt5Core.so.5.4.2)
==6554== by 0x40D302: QHash<QString, QList<QString> >::findNode(QString const&, unsigned int*) const (qhash.h:912)
==6554== by 0x40CBB5: insert (qhash.h:768)
==6554== by 0x40CBB5: PronounceDict::loadDictionary(QString const&) (PronounceDict.cpp:96)
==6554== by 0x40A0E6: (anonymous namespace)::TestPronounceDict_HashesInDictionary_Test::TestBody() (TestPronounceDict.cpp:34)
==6554== by 0x42E182: HandleSehExceptionsInMethodIfSupported<testing::Test, void> (gtest.cc:2078)
==6554== by 0x42E182: void testing::internal::HandleExceptionsInMethodIfSupported<testing::Test, void>(testing::Test*, void (testing::Test::*)(), char const*) (gtest.cc:2114)
==6554== by 0x4260EB: testing::Test::Run() [clone .part.373] (gtest.cc:2151)
==6554== by 0x4262C4: Run (gtest.cc:2142)
==6554== by 0x4262C4: testing::TestInfo::Run() [clone .part.374] (gtest.cc:2326)
==6554== by 0x426434: Run (gtest.cc:2301)
==6554== by 0x426434: testing::TestCase::Run() [clone .part.375] (gtest.cc:2444)
==6554== by 0x4268BC: Run (gtest.cc:4353)
==6554== by 0x4268BC: testing::internal::UnitTestImpl::RunAllTests() (gtest.cc:4315)
==6554== by 0x42E662: HandleSehExceptionsInMethodIfSupported<testing::internal::UnitTestImpl, bool> (gtest.cc:2078)
==6554== by 0x42E662: bool testing::internal::HandleExceptionsInMethodIfSupported<testing::internal::UnitTestImpl, bool>(testing::internal::UnitTestImpl*, bool (testing::internal::UnitTestImpl::*)(), char const*) (gtest.cc:2114)
==6554== by 0x426BD4: testing::UnitTest::Run() (gtest.cc:3926)
(...)

[1] http://people.ubuntuwire.org/~wgrant/rebuild-ftbfs-test/test-rebuild-20151001-wily.html