Update Sanitizer tests for Android R.

[hctim]

Summary

Sanitizer tests don't entirely pass on an R device. Fix up all the
incompatibilities with the new system.

[hctim]

compiler-rt/test/asan/TestCases/Posix/no-fd.cpp

7

"As a general principle, no portable program, whether privileged or not, can assume that these three file descriptors will remain closed across an execve()."

• http://man7.org/linux/man-pages/man2/execve.2.html

[eugenis]

LGTM

compiler-rt/test/asan/TestCases/Posix/no-fd.cpp

 // RUN: %clangxx_asan -std=c++11 -O0 %s -o %t
 // RUN: %run %t 2>&1 | FileCheck %s
 // RUN: %env_asan_opts=debug=1,verbosity=2 %run %t 2>&1 | FileCheck %s
 
 // Test ASan initialization
 
+// This test closes the 0, 1, and 2 file descriptors before an exec() and relies
+// on them remaining closed across an execve(). This is not the case on newer
+// versions of Android.
+// UNSUPPORTED: android
+
 #include <assert.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <unistd.h>
 
 extern "C" const char *__asan_default_options() {
   return "test_only_emulate_no_memorymap=1";
 }

compiler-rt/test/asan/TestCases/strstr_strict.c

 // Test strict_string_checks option in strstr function
 // RUN: %clang_asan %s -o %t && %run %t 2>&1
+
+// Newer versions of Android's strstr() uses memchr() internally, which actually
+// does trigger a heap-buffer-overflow (as it tries to find the
+// null-terminator).
+// UNSUPPORTED: android
 // RUN: %env_asan_opts=strict_string_checks=false %run %t 2>&1
+
 // RUN: %env_asan_opts=strict_string_checks=true not %run %t 2>&1 | FileCheck %s
 
 #include <assert.h>
 #include <stdlib.h>
 #include <string.h>
 
 int main(int argc, char **argv) {
   size_t size = 100;

compiler-rt/test/sanitizer_common/TestCases/Posix/feof_fileno_ferror.cpp

 // RUN: %clangxx -g %s -o %t && %run %t
 
+// Newer versions of Android have FDSan, and will fail this test as FDSan will
+// catch the error instead.
+// UNSUPPORTED: android
+
 #include <assert.h>
 #include <stdio.h>
 #include <unistd.h>
 
 int main(int argc, char **argv) {
   FILE *fp = fopen(argv[0], "r");
   assert(fp);