libsanitizer mege from upstream r171973

From-SVN: r195083

1 files changed, 8 insertions, 0 deletions

diff --git a/libsanitizer/tsan/tsan_flags.cc b/libsanitizer/tsan/tsan_flags.cc
index 1b726e6..630bd75 100644
--- a/libsanitizer/tsan/tsan_flags.cc
+++ b/libsanitizer/tsan/tsan_flags.cc
@@ -56,6 +56,7 @@ void InitializeFlags(Flags *f, const char *env) {
   f->running_on_valgrind = false;
   f->external_symbolizer_path = "";
   f->history_size = kGoMode ? 1 : 2;  // There are a lot of goroutines in Go.
+  f->io_sync = 1;
 
   // Let a frontend override.
   OverrideFlags(f);
@@ -81,6 +82,7 @@ void InitializeFlags(Flags *f, const char *env) {
   ParseFlag(env, &f->stop_on_start, "stop_on_start");
   ParseFlag(env, &f->external_symbolizer_path, "external_symbolizer_path");
   ParseFlag(env, &f->history_size, "history_size");
+  ParseFlag(env, &f->io_sync, "io_sync");
 
   if (!f->report_bugs) {
     f->report_thread_leaks = false;
@@ -93,6 +95,12 @@ void InitializeFlags(Flags *f, const char *env) {
            " (must be [0..7])\n");
     Die();
   }
+
+  if (f->io_sync < 0 || f->io_sync > 2) {
+    Printf("ThreadSanitizer: incorrect value for io_sync"
+           " (must be [0..2])\n");
+    Die();
+  }
 }
 
 }  // namespace __tsan