diff --git a/compiler-rt/lib/hwasan/hwasan_linux.cpp b/compiler-rt/lib/hwasan/hwasan_linux.cpp
--- a/compiler-rt/lib/hwasan/hwasan_linux.cpp
+++ b/compiler-rt/lib/hwasan/hwasan_linux.cpp
@@ -427,7 +427,7 @@
   HandleDeadlySignal(info, context, GetTid(), &OnStackUnwind, nullptr);
 }
 
-void Thread::InitStackAndTls() {
+void Thread::InitStackAndTls(const InitState *state) {
   uptr tls_size;
   uptr stack_size;
   GetThreadStackAndTls(IsMainThread(), &stack_bottom_, &stack_size, &tls_begin_,
diff --git a/compiler-rt/lib/hwasan/hwasan_thread.h b/compiler-rt/lib/hwasan/hwasan_thread.h
--- a/compiler-rt/lib/hwasan/hwasan_thread.h
+++ b/compiler-rt/lib/hwasan/hwasan_thread.h
@@ -23,9 +23,13 @@
 
 class Thread {
  public:
-  void Init(uptr stack_buffer_start, uptr stack_buffer_size);
+  // These are optional parameters that can be passed to Init.
+  struct InitState;
+
+  void Init(uptr stack_buffer_start, uptr stack_buffer_size,
+            const InitState *state = nullptr);
   void InitRandomState();
-  void InitStackAndTls();
+  void InitStackAndTls(const InitState *state = nullptr);
 
   // Must be called from the thread itself.
   void InitStackRingBuffer(uptr stack_buffer_start, uptr stack_buffer_size);
diff --git a/compiler-rt/lib/hwasan/hwasan_thread.cpp b/compiler-rt/lib/hwasan/hwasan_thread.cpp
--- a/compiler-rt/lib/hwasan/hwasan_thread.cpp
+++ b/compiler-rt/lib/hwasan/hwasan_thread.cpp
@@ -34,7 +34,8 @@
     stack_allocations_->push(0);
 }
 
-void Thread::Init(uptr stack_buffer_start, uptr stack_buffer_size) {
+void Thread::Init(uptr stack_buffer_start, uptr stack_buffer_size,
+                  const InitState *state) {
   CHECK_EQ(0, unique_id_);  // try to catch bad stack reuse
   CHECK_EQ(0, stack_top_);
   CHECK_EQ(0, stack_bottom_);
@@ -44,7 +45,7 @@
   if (auto sz = flags()->heap_history_size)
     heap_allocations_ = HeapAllocationsRingBuffer::New(sz);
 
-  InitStackAndTls();
+  InitStackAndTls(state);
   InitStackRingBuffer(stack_buffer_start, stack_buffer_size);
 }
 
diff --git a/compiler-rt/lib/hwasan/hwasan_thread_list.h b/compiler-rt/lib/hwasan/hwasan_thread_list.h
--- a/compiler-rt/lib/hwasan/hwasan_thread_list.h
+++ b/compiler-rt/lib/hwasan/hwasan_thread_list.h
@@ -85,7 +85,7 @@
         RoundUpTo(ring_buffer_size_ + sizeof(Thread), ring_buffer_size_ * 2);
   }
 
-  Thread *CreateCurrentThread() {
+  Thread *CreateCurrentThread(const Thread::InitState *state = nullptr) {
     Thread *t = nullptr;
     {
       SpinMutexLock l(&free_list_mutex_);
@@ -104,7 +104,7 @@
       SpinMutexLock l(&live_list_mutex_);
       live_list_.push_back(t);
     }
-    t->Init((uptr)t - ring_buffer_size_, ring_buffer_size_);
+    t->Init((uptr)t - ring_buffer_size_, ring_buffer_size_, state);
     AddThreadStats(t);
     return t;
   }