Fix test failure when using clang++ and release mode
Fix test failure when using clang++ and release mode

Signed-off-by: Leonardo de Moura <7610bae85f2b530654cc716772f1fe653373e892@microsoft.com>

dselsam/lean,fpvandoorn/lean,Kha/lean,johoelzl/lean,leanprover/lean,sp3ctum/lean,levnach/lean,UlrikBuchholtz/lean,levnach/lean,c-cube/lean,leanprover-community/lean,fpvandoorn/lean2,johoelzl/lean,johoelzl/lean,levnach/lean,htzh/lean,Kha/lean,sp3ctum/lean,dselsam/lean,Kha/lean,UlrikBuchholtz/lean,soonhokong/lean-osx,johoelzl/lean,leodemoura/lean,soonhokong/lean-windows,eigengrau/lean,javra/lean,digama0/lean,fpvandoorn/lean,leodemoura/lean,avigad/lean,fgdorais/lean,rlewis1988/lean,eigengrau/lean,rlewis1988/lean,leanprover/lean,leodemoura/lean,levnach/lean,htzh/lean,leanprover-community/lean,leodemoura/lean,dselsam/lean,Kha/lean,htzh/lean,codyroux/lean0.1,leanprover-community/lean,dselsam/lean,leanprover/lean,fgdorais/lean,soonhokong/travis_test,fpvandoorn/lean2,soonhokong/lean-windows,soonhokong/lean,UlrikBuchholtz/lean,leodemoura/lean,fgdorais/lean,htzh/lean,javra/lean,eigengrau/lean,c-cube/lean,soonhokong/travis_test,sp3ctum/lean,fgdorais/lean,johoelzl/lean,soonhokong/travis_test,dselsam/lean,rlewis1988/lean,soonhokong/lean-osx,c-cube/lean,eigengrau/lean,soonhokong/lean-windows,digama0/lean,c-cube/lean,htzh/lean,soonhokong/lean,sp3ctum/lean,digama0/lean,digama0/lean,rlewis1988/lean,soonhokong/lean-windows,sp3ctum/lean,dselsam/lean,soonhokong/lean-osx,soonhokong/lean-windows,levnach/lean,leanprover-community/lean,soonhokong/lean,fpvandoorn/lean,johoelzl/lean,Kha/lean,fpvandoorn/lean,soonhokong/lean-osx,javra/lean,leanprover-community/lean,codyroux/lean0.1,codyroux/lean0.1,digama0/lean,avigad/lean,leanprover/lean,rlewis1988/lean,fpvandoorn/lean2,avigad/lean,codyroux/lean0.1,fgdorais/lean,leodemoura/lean,avigad/lean,javra/lean,leanprover-community/lean,rlewis1988/lean,fpvandoorn/lean2,fgdorais/lean,digama0/lean,UlrikBuchholtz/lean,fpvandoorn/lean,eigengrau/lean,c-cube/lean,leanprover/lean,avigad/lean,soonhokong/lean,fpvandoorn/lean,javra/lean,avigad/lean,soonhokong/lean-osx,soonhokong/travis_test,soonhokong/lean,leanprover/lean,Kha/lean,UlrikBuchholtz/lean,fpvandoorn/lean2