diff --git a/llvm/utils/gn/secondary/llvm/lib/Support/BUILD.gn b/llvm/utils/gn/secondary/llvm/lib/Support/BUILD.gn
index 258e513b7c376..fab37e8ecc1eb 100644
--- a/llvm/utils/gn/secondary/llvm/lib/Support/BUILD.gn
+++ b/llvm/utils/gn/secondary/llvm/lib/Support/BUILD.gn
@@ -135,6 +135,7 @@ static_library("Support") {
     "TrigramIndex.cpp",
     "Triple.cpp",
     "Twine.cpp",
+    "TypeSize.cpp",
     "Unicode.cpp",
     "UnicodeCaseFold.cpp",
     "VersionTuple.cpp",