[ASan] Print a hint when the program crashes accessing the zero page.
This may help some users figure out that the error report is valid.


git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@218123 91177308-0d34-0410-b5e6-96231b3b80d8
[asan] asan_device_setup improvements.

* Allow user SEGV handler if Android-L-like setup is detected.
  Necessary for correctness.
* Change file context labels on the wrapper script to appease SELinux.


git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@218124 91177308-0d34-0410-b5e6-96231b3b80d8
[UBSan] Optionally report summary in UBSan error reports.

By default summary is not printed if UBSan is run in a standalone mode,
but is printed if it's combined with another sanitizer (like ASan).


git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@218135 91177308-0d34-0410-b5e6-96231b3b80d8
[UBSan] Introduce more flexible __ubsan_default_options function instead of UBSAN_DEFAULT_OPTIONS compile definition

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@218137 91177308-0d34-0410-b5e6-96231b3b80d8