diff --git a/include/ghc/filesystem.hpp b/include/ghc/filesystem.hpp
index 477447c..c901b03 100644
--- a/include/ghc/filesystem.hpp
+++ b/include/ghc/filesystem.hpp
@@ -1109,7 +1109,7 @@ class basic_filebuf : public std::basic_filebuf<charT, traits>
     const basic_filebuf& operator=(const basic_filebuf&) = delete;
     basic_filebuf<charT, traits>* open(const path& p, std::ios_base::openmode mode)
     {
-#if defined(GHC_OS_WINDOWS) && !defined(__GNUC__)
+#if defined(GHC_OS_WINDOWS) && !defined(__GLIBCXX__)
         return std::basic_filebuf<charT, traits>::open(p.wstring().c_str(), mode) ? this : 0;
 #else
         return std::basic_filebuf<charT, traits>::open(p.string().c_str(), mode) ? this : 0;
@@ -1122,7 +1122,7 @@ class basic_ifstream : public std::basic_ifstream<charT, traits>
 {
 public:
     basic_ifstream() {}
-#if defined(GHC_OS_WINDOWS) && !defined(__GNUC__)
+#if defined(GHC_OS_WINDOWS) && !defined(__GLIBCXX__)
     explicit basic_ifstream(const path& p, std::ios_base::openmode mode = std::ios_base::in)
         : std::basic_ifstream<charT, traits>(p.wstring().c_str(), mode)
     {
@@ -1145,7 +1145,7 @@ class basic_ofstream : public std::basic_ofstream<charT, traits>
 {
 public:
     basic_ofstream() {}
-#if defined(GHC_OS_WINDOWS) && !defined(__GNUC__)
+#if defined(GHC_OS_WINDOWS) && !defined(__GLIBCXX__)
     explicit basic_ofstream(const path& p, std::ios_base::openmode mode = std::ios_base::out)
         : std::basic_ofstream<charT, traits>(p.wstring().c_str(), mode)
     {
@@ -1168,7 +1168,7 @@ class basic_fstream : public std::basic_fstream<charT, traits>
 {
 public:
     basic_fstream() {}
-#if defined(GHC_OS_WINDOWS) && !defined(__GNUC__)
+#if defined(GHC_OS_WINDOWS) && !defined(__GLIBCXX__)
     explicit basic_fstream(const path& p, std::ios_base::openmode mode = std::ios_base::in | std::ios_base::out)
         : std::basic_fstream<charT, traits>(p.wstring().c_str(), mode)
     {