diff --git a/llvm/utils/gn/secondary/llvm/lib/Support/BUILD.gn b/llvm/utils/gn/secondary/llvm/lib/Support/BUILD.gn
index df9ddf91f2c49..bc4047cb3be52 100644
--- a/llvm/utils/gn/secondary/llvm/lib/Support/BUILD.gn
+++ b/llvm/utils/gn/secondary/llvm/lib/Support/BUILD.gn
@@ -190,6 +190,7 @@ static_library("Support") {
     "regfree.c",
     "regstrlcpy.c",
     "xxhash.cpp",
+    "zOSLibFunctions.cpp",
 
     # System
     "Atomic.cpp",