diff --git a/llvm/utils/gn/secondary/libcxx/include/BUILD.gn b/llvm/utils/gn/secondary/libcxx/include/BUILD.gn
index afc417234ebd7..b05f67e530c9e 100644
--- a/llvm/utils/gn/secondary/libcxx/include/BUILD.gn
+++ b/llvm/utils/gn/secondary/libcxx/include/BUILD.gn
@@ -265,6 +265,7 @@ if (current_toolchain == default_toolchain) {
       "__filesystem/space_info.h",
       "__filesystem/u8path.h",
       "__format/buffer.h",
+      "__format/concepts.h",
       "__format/enable_insertable.h",
       "__format/format_arg.h",
       "__format/format_args.h",