diff --git a/utils/gn/secondary/llvm/tools/llvm-reduce/BUILD.gn b/utils/gn/secondary/llvm/tools/llvm-reduce/BUILD.gn
index a689ccc21e7..6702a79eed6 100644
--- a/utils/gn/secondary/llvm/tools/llvm-reduce/BUILD.gn
+++ b/utils/gn/secondary/llvm/tools/llvm-reduce/BUILD.gn
@@ -12,6 +12,7 @@ executable("llvm-reduce") {
     "TestRunner.cpp",
     "deltas/Delta.cpp",
     "deltas/ReduceArguments.cpp",
+    "deltas/ReduceBasicBlocks.cpp",
     "deltas/ReduceFunctions.cpp",
     "deltas/ReduceGlobalVars.cpp",
     "deltas/ReduceMetadata.cpp",