diff --git a/include/toml11/fwd/source_location_fwd.hpp b/include/toml11/fwd/source_location_fwd.hpp
index 73e107e..77c7579 100644
--- a/include/toml11/fwd/source_location_fwd.hpp
+++ b/include/toml11/fwd/source_location_fwd.hpp
@@ -107,10 +107,8 @@ std::string format_location(
 {
     const auto lnw = detail::line_width(loc, msg, tail...);
 
-    std::ostringstream oss;
-    detail::format_filename(oss, loc);
-
-    return oss.str() + detail::format_location_rec(lnw, loc.file_name(), loc, msg, tail...);
+    const std::string f(""); // at the 1st iteration, no prev_filename is given
+    return detail::format_location_rec(lnw, f, loc, msg, tail...);
 }
 
 } // toml