diff --git a/llvm/utils/gn/secondary/llvm/lib/Support/BUILD.gn b/llvm/utils/gn/secondary/llvm/lib/Support/BUILD.gn
index 150847aa9b05..3ef6a1f12031 100644
--- a/llvm/utils/gn/secondary/llvm/lib/Support/BUILD.gn
+++ b/llvm/utils/gn/secondary/llvm/lib/Support/BUILD.gn
@@ -96,6 +96,7 @@ static_library("Support") {
     "MathExtras.cpp",
     "MemAlloc.cpp",
     "MemoryBuffer.cpp",
+    "MemoryBufferRef.cpp",
     "NativeFormatting.cpp",
     "OptimizedStructLayout.cpp",
     "Optional.cpp",
diff --git a/llvm/utils/gn/secondary/llvm/unittests/Support/BUILD.gn b/llvm/utils/gn/secondary/llvm/unittests/Support/BUILD.gn
index 2aee1db5086e..890f8a46e383 100644
--- a/llvm/utils/gn/secondary/llvm/unittests/Support/BUILD.gn
+++ b/llvm/utils/gn/secondary/llvm/unittests/Support/BUILD.gn
@@ -53,6 +53,7 @@ unittest("SupportTests") {
     "ManagedStatic.cpp",
     "MatchersTest.cpp",
     "MathExtrasTest.cpp",
+    "MemoryBufferRefTest.cpp",
     "MemoryBufferTest.cpp",
     "MemoryTest.cpp",
     "NativeFormatTests.cpp",