diff --git a/webrtc/base/BUILD.gn b/webrtc/base/BUILD.gn
index 5cb428727e..d1ff2fb91f 100644
--- a/webrtc/base/BUILD.gn
+++ b/webrtc/base/BUILD.gn
@@ -521,6 +521,8 @@ static_library("rtc_base") {
     all_dependent_configs = [ ":ios_config" ]
 
     sources += [
+      "maccocoathreadhelper.h",
+      "maccocoathreadhelper.mm",
       "macconversion.cc",
       "macconversion.h",
     ]