App: workaround for boost's file_lock with version < 1.76 on Windows

src/App/Application.cpp

@@ -3069,6 +3069,15 @@ std::tuple<QString, QString, QString, QString> getStandardPaths()
 #if defined(FC_OS_WIN32)
     configHome = getOldGenericDataLocation(QString());
     dataHome = configHome;
+
+    // On systems with non-7-bit-ASCII application data directories
+    // GetTempPathW will return a path in DOS format. This path will be
+    // accepted by boost's file_lock class.
+    // Since boost 1.76 there is now a version that accepts a wide string.
+#if (BOOST_VERSION < 107600)
+    tempPath = QString::fromStdString(Base::FileInfo::getTempPath());
+    cacheHome = tempPath;
+#endif
 #endif
 
     return std::make_tuple(configHome, dataHome, cacheHome, tempPath);