Index: lib/tsan/CMakeLists.txt
===================================================================
--- lib/tsan/CMakeLists.txt
+++ lib/tsan/CMakeLists.txt
@@ -39,7 +39,6 @@
   rtl/tsan_mman.cc
   rtl/tsan_mutex.cc
   rtl/tsan_mutexset.cc
-  rtl/tsan_preinit.cc
   rtl/tsan_report.cc
   rtl/tsan_rtl.cc
   rtl/tsan_rtl_mutex.cc
Index: lib/tsan/rtl/tsan_preinit.cc
===================================================================
--- lib/tsan/rtl/tsan_preinit.cc
+++ /dev/null
@@ -1,27 +0,0 @@
-//===-- tsan_preinit.cc ---------------------------------------------------===//
-//
-//                     The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-//
-// This file is a part of ThreadSanitizer.
-//
-// Call __tsan_init at the very early stage of process startup.
-//===----------------------------------------------------------------------===//
-
-#include "sanitizer_common/sanitizer_internal_defs.h"
-#include "tsan_interface.h"
-
-#if SANITIZER_CAN_USE_PREINIT_ARRAY
-
-// The symbol is called __local_tsan_preinit, because it's not intended to be
-// exported.
-// This code linked into the main executable when -fsanitize=thread is in
-// the link flags. It can only use exported interface functions.
-__attribute__((section(".preinit_array"), used))
-void (*__local_tsan_preinit)(void) = __tsan_init;
-
-#endif
Index: lib/tsan/rtl/tsan_rtl.cc
===================================================================
--- lib/tsan/rtl/tsan_rtl.cc
+++ lib/tsan/rtl/tsan_rtl.cc
@@ -66,6 +66,8 @@
 
 static char thread_registry_placeholder[sizeof(ThreadRegistry)];
 
+static bool is_initialized = false;
+
 static ThreadContextBase *CreateThreadContext(u32 tid) {
   // Map thread trace when context is created.
   char name[50];
@@ -324,7 +326,6 @@
 
 void Initialize(ThreadState *thr) {
   // Thread safe because done before all threads exist.
-  static bool is_initialized = false;
   if (is_initialized)
     return;
   is_initialized = true;
@@ -944,6 +945,8 @@
 
 ALWAYS_INLINE USED
 void FuncEntry(ThreadState *thr, uptr pc) {
+  if (!is_initialized)
+    Initialize(thr);
   StatInc(thr, StatFuncEnter);
   DPrintf2("#%d: FuncEntry %p\n", (int)thr->fast_state.tid(), (void*)pc);
   if (kCollectHistory) {
Index: test/tsan/Linux/check_preinit.cc
===================================================================
--- test/tsan/Linux/check_preinit.cc
+++ test/tsan/Linux/check_preinit.cc
@@ -1,16 +1,12 @@
 // RUN: %clang_tsan -fno-sanitize=thread -shared -fPIC -O1 -DBUILD_SO=1 %s -o \
 // RUN:  %t.so && \
 // RUN:   %clang_tsan -O1 %s %t.so -o %t && %run %t 2>&1 | FileCheck %s
-// RUN: llvm-objdump -t %t | FileCheck %s --check-prefix=CHECK-DUMP
-// CHECK-DUMP:  {{[.]preinit_array.*__local_tsan_preinit}}
 
 // SANITIZER_CAN_USE_PREINIT_ARRAY is undefined on android.
 // UNSUPPORTED: android
 
-// Test checks if __tsan_init is called from .preinit_array.
-// Without initialization from .preinit_array, __tsan_init will be called from
-// constructors of the binary which are called after constructors of shared
-// library.
+// Test checks that instrumented code triggers __tsan_init even if it's called
+// as early as from .preinit_array.
 
 #include <stdio.h>
 
@@ -20,6 +16,7 @@
 volatile int counter = 0;
 volatile int lib_constructor_call = 0;
 volatile int tsan_init_call = 0;
+volatile int preinit_array_call = 0;
 
 __attribute__ ((constructor))
 void LibConstructor() {
@@ -31,6 +28,7 @@
 extern int counter;
 extern int lib_constructor_call;
 extern int tsan_init_call;
+extern int preinit_array_call;
 
 volatile int bin_constructor_call = 0;
 
@@ -47,11 +45,20 @@
 
 }
 
+void PreinitArray() {
+  preinit_array_call = ++counter;
+};
+
+__attribute__((section(".preinit_array"), used))
+void (*__preinit_test)(void) = PreinitArray;
+
 int main() {
   // CHECK: TSAN_INIT 1
-  // CHECK: LIB_CONSTRUCTOR 2
-  // CHECK: BIN_CONSTRUCTOR 3
+  // CHECK: PREINIT_ARRAY 2
+  // CHECK: LIB_CONSTRUCTOR 3
+  // CHECK: BIN_CONSTRUCTOR 4
   printf("TSAN_INIT %d\n", tsan_init_call);
+  printf("PREINIT_ARRAY %d\n", preinit_array_call);
   printf("LIB_CONSTRUCTOR %d\n", lib_constructor_call);
   printf("BIN_CONSTRUCTOR %d\n", bin_constructor_call);
   return 0;