diff --git a/llvm/utils/gn/secondary/libcxx/include/BUILD.gn b/llvm/utils/gn/secondary/libcxx/include/BUILD.gn
index 4d12cf7cbff73..2eae476bc5ee4 100644
--- a/llvm/utils/gn/secondary/libcxx/include/BUILD.gn
+++ b/llvm/utils/gn/secondary/libcxx/include/BUILD.gn
@@ -86,6 +86,7 @@ if (current_toolchain == default_toolchain) {
       "__algorithm/generate.h",
       "__algorithm/generate_n.h",
       "__algorithm/half_positive.h",
+      "__algorithm/in_in_result.h",
       "__algorithm/in_out_result.h",
       "__algorithm/includes.h",
       "__algorithm/inplace_merge.h",