diff --git a/utils/gn/secondary/llvm/unittests/Support/BUILD.gn b/utils/gn/secondary/llvm/unittests/Support/BUILD.gn
index 4400db8..00a5bfa 100644
--- a/utils/gn/secondary/llvm/unittests/Support/BUILD.gn
+++ b/utils/gn/secondary/llvm/unittests/Support/BUILD.gn
@@ -37,6 +37,7 @@
     "Host.cpp",
     "ItaniumManglingCanonicalizerTest.cpp",
     "JSONTest.cpp",
+    "KnownBitsTest.cpp",
     "LEB128Test.cpp",
     "LineIteratorTest.cpp",
     "LockFileManagerTest.cpp",