Index: lib/asan/asan_thread.h
===================================================================
--- lib/asan/asan_thread.h
+++ lib/asan/asan_thread.h
@@ -117,6 +117,8 @@
       return nullptr;
     if (atomic_load(&stack_switching_, memory_order_relaxed))
       return nullptr;
+    if (!has_fake_stack())
+      return AsyncSignalSafeLazyInitFakeStack();
     return fake_stack_;
   }