--- a/src/portable.cpp
+++ b/src/portable.cpp
@@ -667,7 +667,7 @@
   std::ios_base::openmode mode = std::ofstream::out | std::ofstream::binary;
   if (append) mode |= std::ofstream::app;
 #if defined(__clang__) && defined(__MINGW32__)
-  return std::ofstream(fs::path(fileName.str()).wstring(), mode);
+  return std::ofstream(fs::path(fileName.str()).string(), mode);
 #else
   return std::ofstream(fs::path(fileName.str()), mode);
 #endif
@@ -679,7 +679,7 @@
   if (binary)     mode |= std::ios::binary;
   if (openAtEnd)  mode |= std::ios::ate;
 #if defined(__clang__) && defined(__MINGW32__)
-  return std::ifstream(fs::path(fileName.str()).wstring(), mode);
+  return std::ifstream(fs::path(fileName.str()).string(), mode);
 #else
   return std::ifstream(fs::path(fileName.str()), mode);
 #endif
