1 files changed, 2 insertions, 0 deletions
diff --git a/absl/synchronization/internal/kernel_timeout.h b/absl/synchronization/internal/kernel_timeout.h
index a83c427b..0d132d98 100644
--- a/absl/synchronization/internal/kernel_timeout.h
+++ b/absl/synchronization/internal/kernel_timeout.h
@@ -39,6 +39,7 @@
 namespace absl {
 namespace synchronization_internal {
 
+class Futex;
 class Waiter;
 
 class KernelTimeout {
@@ -139,6 +140,7 @@ class KernelTimeout {
   }
 #endif
 
+  friend class Futex;
   friend class Waiter;
 };