[libsanitizer] Use internal_fork() to spawn the symbolizer process.

This should fix https://code.google.com/p/thread-sanitizer/issues/detail?id=61


git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@208707 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 31 insertions, 0 deletions

diff --git a/test/tsan/pthread_atfork_deadlock.c b/test/tsan/pthread_atfork_deadlock.c
new file mode 100644
index 000000000..27dff46b9
--- /dev/null
+++ b/test/tsan/pthread_atfork_deadlock.c
@@ -0,0 +1,31 @@
+// RUN: %clang_tsan -O1 %s -o %t && not %run %t 2>&1 | FileCheck %s
+// Regression test for
+// https://code.google.com/p/thread-sanitizer/issues/detail?id=61
+// When the data race was reported, pthread_atfork() handler used to be
+// executed which caused another race report in the same thread, which resulted
+// in a deadlock.
+#include <pthread.h>
+#include <stdio.h>
+
+int glob = 0;
+
+void *worker(void *unused) {
+  glob++;
+  return NULL;
+}
+
+void atfork() {
+  fprintf(stderr, "ATFORK\n");
+  glob++;
+}
+
+int main() {
+  pthread_atfork(atfork, NULL, NULL);
+  pthread_t t;
+  pthread_create(&t, NULL, worker, NULL);
+  glob++;
+  pthread_join(t, NULL);
+  // CHECK: ThreadSanitizer: data race
+  // CHECK-NOT: ATFORK
+  return 0;
+}