This variable is used by ASan (and other sanitizers in the future)
on s390x-linux to override a check for CVE-2016-2143 in the running
kernel (see revision 267747 on compiler-rt). Since the check simply
checks if the kernel version is in a whitelist of known-good versions,
it may miss distribution kernels, or manually-patched kernels - hence
the need for this variable. To enable running the ASan testsuite on
such kernels, this variable should be passed from the environment
down to the testcases.
Differential Revision: http://reviews.llvm.org/D19888
llvm-svn: 273825
6a9131b3fe