[gn build] Port d65557d15d4
diff --git a/llvm/utils/gn/secondary/llvm/lib/MC/BUILD.gn b/llvm/utils/gn/secondary/llvm/lib/MC/BUILD.gn
index 902f9c0..e0c7701 100644
--- a/llvm/utils/gn/secondary/llvm/lib/MC/BUILD.gn
+++ b/llvm/utils/gn/secondary/llvm/lib/MC/BUILD.gn
@@ -55,6 +55,7 @@
     "MCSubtargetInfo.cpp",
     "MCSymbol.cpp",
     "MCSymbolELF.cpp",
+    "MCSymbolXCOFF.cpp",
     "MCTargetOptions.cpp",
     "MCTargetOptionsCommandFlags.cpp",
     "MCValue.cpp",