From c4683aa4a188d500dfdf026d7373e175500ebc22 Mon Sep 17 00:00:00 2001
From: Oz <rik20@live.it>
Date: Tue, 5 Sep 2023 09:00:51 +0200
Subject: [PATCH] Allow wchar_t constructors of iostreams on Windows when using
 libstdc++

---
 include/ghc/filesystem.hpp | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/include/ghc/filesystem.hpp b/include/ghc/filesystem.hpp
index c7e9f54..86a6392 100644
--- a/include/ghc/filesystem.hpp
+++ b/include/ghc/filesystem.hpp
@@ -1142,6 +1142,10 @@ GHC_FS_API void create_hard_link(const path& to, const path& new_hard_link, std:
 GHC_FS_API uintmax_t hard_link_count(const path& p, std::error_code& ec) noexcept;
 #endif
 
+#if defined(GHC_OS_WINDOWS) && (!defined(__GLIBCXX__) || (defined(_GLIBCXX_HAVE__WFOPEN) && defined(_GLIBCXX_USE_WCHAR_T)))
+#define GHC_HAS_FSTREAM_OPEN_WITH_WCHAR
+#endif
+
 // Non-C++17 add-on std::fstream wrappers with path
 template <class charT, class traits = std::char_traits<charT>>
 class basic_filebuf : public std::basic_filebuf<charT, traits>
@@ -1153,7 +1157,7 @@ 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(__GLIBCXX__)
+#ifdef GHC_HAS_FSTREAM_OPEN_WITH_WCHAR
         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;
@@ -1166,7 +1170,7 @@ class basic_ifstream : public std::basic_ifstream<charT, traits>
 {
 public:
     basic_ifstream() {}
-#if defined(GHC_OS_WINDOWS) && !defined(__GLIBCXX__)
+#ifdef GHC_HAS_FSTREAM_OPEN_WITH_WCHAR
     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)
     {
@@ -1189,7 +1193,7 @@ class basic_ofstream : public std::basic_ofstream<charT, traits>
 {
 public:
     basic_ofstream() {}
-#if defined(GHC_OS_WINDOWS) && !defined(__GLIBCXX__)
+#ifdef GHC_HAS_FSTREAM_OPEN_WITH_WCHAR
     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)
     {
@@ -1212,7 +1216,7 @@ class basic_fstream : public std::basic_fstream<charT, traits>
 {
 public:
     basic_fstream() {}
-#if defined(GHC_OS_WINDOWS) && !defined(__GLIBCXX__)
+#ifdef GHC_HAS_FSTREAM_OPEN_WITH_WCHAR
     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)
     {