[android] Fix some tests for AOSP-master devices.

Some tests are broken at API level 30 on AOSP-master devices. When we
change the buildbuit to API level 30, the following tests get enabled.
They're currently broken due to various issues, and so fix up those
issues.

Reviewed By: oontvoo, eugenis

Differential Revision: https://reviews.llvm.org/D94100

compiler-rt/test/cfi/cross-dso/target_out_of_bounds.cpp

@@ -10,6 +10,12 @@
 
 // REQUIRES: cxxabi
 
+// These checks are unsupported on newer versions of Android due to the
+// following patch that makes it harder to defeat ASLR by not mapping unused
+// shadow regions:
+// https://android-review.googlesource.com/c/platform/bionic/+/1333960
+// UNSUPPORTED: android
+
 #include <stdio.h>
 #include <stdint.h>
 #include <stdlib.h>

compiler-rt/test/lsan/TestCases/Linux/use_tls_dynamic.cpp

@@ -23,6 +23,11 @@
 int main(int argc, char *argv[]) {
   std::string path = std::string(argv[0]) + "-so.so";
 
+  // Clear any previous errors. On Android, the dynamic loader can have some
+  // left over dlerror() messages due to a missing symbol resolution for a
+  // deprecated malloc function.
+  dlerror();
+
   void *handle = dlopen(path.c_str(), RTLD_LAZY);
   assert(handle != 0);
   typedef void **(* store_t)(void *p);
@@ -31,10 +36,10 @@ int main(int argc, char *argv[]) {
   // Sometimes dlerror() occurs when we broke the interceptors.
   // Add the message here to make the error more obvious.
   const char *dlerror_msg = dlerror();
-  assert(dlerror_msg == nullptr);
   if (dlerror_msg != nullptr) {
     fprintf(stderr, "DLERROR: %s\n", dlerror_msg);
     fflush(stderr);
+    abort();
   }
   void *p = malloc(1337);
   // If we don't  know about dynamic TLS, we will return a false leak above.

compiler-rt/test/lsan/TestCases/stale_stack_leak.cpp

@@ -1,6 +1,15 @@
 // Test that out-of-scope local variables are ignored by LSan.
 // RUN: LSAN_BASE="report_objects=1:use_registers=0:use_stacks=1"
-// RUN: %clangxx_lsan %s -o %t
+
+// LSan-in-ASan fails at -O0 on aarch64, because the stack use-after-return
+// instrumentation stashes the argument to `PutPointerOnStaleStack` on the stack
+// in order to conditionally call __asan_stack_malloc. This subverts our
+// expectations for this test, where we assume the pointer is never stashed
+// except at the bottom of the dead frame. Building at -O1 or greater solves
+// this problem, because the compiler is smart enough to stash the argument in a
+// callee-saved register for rematerialization instead.
+// RUN: %clangxx_lsan -O1 %s -o %t
+
 // RUN: %env_lsan_opts=$LSAN_BASE not %run %t 2>&1 | FileCheck %s
 // RUN: %env_lsan_opts=$LSAN_BASE":exitcode=0" %run %t 2>&1 | FileCheck --check-prefix=CHECK-sanity %s
 //