--- /dev/null
+// UNSUPPORTED: ios
+// REQUIRES: shell
+// REQUIRES: darwin_log_cmd
+// RUN: %clangxx_asan -fsanitize-recover=address %s -o %t
+// RUN: { %env_asan_opts=halt_on_error=0,log_to_syslog=1 %run %t > %t.process_output.txt 2>&1 & } \
+// RUN: ; export TEST_PID=$! ; wait ${TEST_PID}
+
+// Check process output.
+// RUN: FileCheck %s --check-prefixes CHECK,CHECK-PROC -input-file=%t.process_output.txt
+
+// Check syslog output. We filter recent system logs based on PID to avoid
+// getting the logs of previous test runs.
+// RUN: log show --debug --last 2m --predicate "processID == ${TEST_PID}" --style syslog > %t.process_syslog_output.txt
+// RUN: FileCheck %s -input-file=%t.process_syslog_output.txt
+#include <cassert>
+#include <cstdio>
+#include <sanitizer/asan_interface.h>
+
+const int kBufferSize = 512;
+char *buffer;
+
+// `readZero` and `readOne` exist so that we can distinguish the two
+// error reports based on the symbolized stacktrace.
+void readZero() {
+ assert(__asan_address_is_poisoned(buffer));
+ char c = buffer[0];
+ printf("Read %c\n", c);
+}
+
+void readOne() {
+ assert(__asan_address_is_poisoned(buffer + 1));
+ char c = buffer[1];
+ printf("Read %c\n", c);
+}
+
+int main() {
+ buffer = static_cast<char *>(malloc(kBufferSize));
+ assert(buffer);
+ // Deliberately poison `buffer` so that we have a deterministic way
+ // triggering two ASan reports in a row in the no halt_on_error mode (e.g. Two
+ // heap-use-after free in a row might not be deterministic).
+ __asan_poison_memory_region(buffer, kBufferSize);
+
+ // This sequence of ASan reports are designed to catch an old bug in the way
+ // ASan's internal syslog buffer was handled after reporting an issue.
+ // Previously in the no halt_on_error mode the internal buffer wasn't cleared
+ // after reporting an issue. When another issue was encountered everything
+ // that was already in the buffer would be written to the syslog again
+ // leading to duplicate reports in the syslog.
+
+ // First bad access.
+ // CHECK: use-after-poison
+ // CHECK-NEXT: READ of size 1
+ // CHECK-NEXT: #0 0x{{[0-9a-f]+}} in readZero
+ // CHECK: SUMMARY: {{.*}} use-after-poison {{.*}} in readZero
+ readZero();
+
+ // Second bad access.
+ // CHECK: use-after-poison
+ // CHECK-NEXT: READ of size 1
+ // CHECK-NEXT: #0 0x{{[0-9a-f]+}} in readOne
+ // CHECK: SUMMARY: {{.*}} use-after-poison {{.*}} in readOne
+ readOne();
+
+ // CHECK-PROC: DONE
+ printf("DONE\n");
+ return 0;
+}