These tests were added in:
1daa48f005bd477ba8711ecdf91a1f1515f01383
59e422c90bf4796fc73237e838d8954b4e2099b1
malloc_zero.c and realloc_too_big.c fail when only
leak sanitizer is enabled.
http://lab.llvm.org:8011/#/builders/59/builds/1635
(also in an armv8 32 bit build)
(I would XFAIL them but the same test is run with
address and leak sanitizer enabled and that one does
pass)