diff --git a/gn/gpu.gni b/gn/gpu.gni
index aa84069..5c6b238 100644
--- a/gn/gpu.gni
+++ b/gn/gpu.gni
@@ -8,6 +8,7 @@
 _include = get_path_info("../include", "abspath")
 
 skia_gpu_sources = [
+  "$_include/gpu/GrBackendSemaphore.h",
   "$_include/gpu/GrBackendSurface.h",
   "$_include/gpu/GrBlend.h",
   "$_include/gpu/GrCaps.h",