diff --git a/llvm/utils/gn/secondary/clang/lib/CodeGen/BUILD.gn b/llvm/utils/gn/secondary/clang/lib/CodeGen/BUILD.gn
--- a/llvm/utils/gn/secondary/clang/lib/CodeGen/BUILD.gn
+++ b/llvm/utils/gn/secondary/clang/lib/CodeGen/BUILD.gn
@@ -80,6 +80,7 @@
     "MicrosoftCXXABI.cpp",
     "ModuleBuilder.cpp",
     "ObjectFilePCHContainerOperations.cpp",
+    "PatternInit.cpp",
     "SanitizerMetadata.cpp",
     "SwiftCallingConv.cpp",
     "TargetInfo.cpp",