diff --git a/llvm/utils/gn/secondary/llvm/tools/llvm-reduce/BUILD.gn b/llvm/utils/gn/secondary/llvm/tools/llvm-reduce/BUILD.gn
index 1a730763ec254..793ca8372f91d 100644
--- a/llvm/utils/gn/secondary/llvm/tools/llvm-reduce/BUILD.gn
+++ b/llvm/utils/gn/secondary/llvm/tools/llvm-reduce/BUILD.gn
@@ -25,6 +25,7 @@ executable("llvm-reduce") {
     "deltas/ReduceGlobalVarInitializers.cpp",
     "deltas/ReduceGlobalVars.cpp",
     "deltas/ReduceIRReferences.cpp",
+    "deltas/ReduceInstructionFlagsMIR.cpp",
     "deltas/ReduceInstructions.cpp",
     "deltas/ReduceInstructionsMIR.cpp",
     "deltas/ReduceMetadata.cpp",