[TSan] Automatically pick up llvm-symbolizer from PATH, as we do in another sanitizers

llvm-svn: 191954

compiler-rt/lib/tsan/lit_tests/Unit/lit.cfg

@@ -21,11 +21,3 @@ config.test_exec_root = os.path.join(llvm_obj_root, "projects",
                                      "compiler-rt", "lib",
                                      "tsan", "tests")
 config.test_source_root = config.test_exec_root
-
-# Get path to external LLVM symbolizer to run ThreadSanitizer unit tests.
-llvm_tools_dir = getattr(config, 'llvm_tools_dir', None)
-if llvm_tools_dir:
-  llvm_symbolizer_path = os.path.join(llvm_tools_dir, "llvm-symbolizer")
-  config.environment['TSAN_OPTIONS'] = ("external_symbolizer_path=" +
-                                        llvm_symbolizer_path)
-

compiler-rt/lib/tsan/lit_tests/lit.cfg

@@ -53,8 +53,6 @@ if llvm_src_root is None:
 
 # Setup environment variables for running ThreadSanitizer.
 tsan_options = "atexit_sleep_ms=0"
-# Set path to external LLVM symbolizer to run ThreadSanitizer output tests.
-tsan_options += " " + "external_symbolizer_path=" + config.llvm_symbolizer_path
 
 config.environment['TSAN_OPTIONS'] = tsan_options
 

compiler-rt/lib/tsan/rtl/tsan_rtl.cc

@@ -238,12 +238,13 @@ void Initialize(ThreadState *thr) {
   InitializeLibIgnore();
   // Initialize external symbolizer before internal threads are started.
   const char *external_symbolizer = flags()->external_symbolizer_path;
-  if (external_symbolizer != 0 && external_symbolizer[0] != '\0') {
-    if (!getSymbolizer()->InitializeExternal(external_symbolizer)) {
-      Printf("Failed to start external symbolizer: '%s'\n",
-             external_symbolizer);
-      Die();
-    }
+  bool symbolizer_started =
+      getSymbolizer()->InitializeExternal(external_symbolizer);
+  if (external_symbolizer != 0 && external_symbolizer[0] != '\0' &&
+      !symbolizer_started) {
+    Printf("Failed to start external symbolizer: '%s'\n",
+           external_symbolizer);
+    Die();
   }
 #endif
   internal_start_thread(&BackgroundThread, 0);