Display pop-up message when fatal error occured on windows.

The reason to do it is that in release mode we don't receive any message in console. This causes that the game sometimes doesn't start and you have no idea why (for example missing supertuxkart.git file etc.).

src/utils/log.cpp

@@ -197,7 +197,7 @@ void Log::printMessage(int level, const char *component, const char *format,
     OutputDebugString(szBuff);
     OutputDebugString("\r\n");
 #endif
-    
+
 
     if(m_file_stdout)
     {
@@ -207,6 +207,25 @@ void Log::printMessage(int level, const char *component, const char *format,
         va_end(copy);
     }
 
+#ifdef WIN32
+    if (level >= LL_FATAL)
+    {
+        std::string message;
+
+        char tmp[2048];
+        sprintf(tmp, "[%s] %s: ", names[level], component);
+        message += tmp;
+
+        VALIST out;
+        va_copy(out, args);
+        vsprintf(tmp, format, out);
+        message += tmp;
+        va_end(out);
+
+        MessageBoxA(NULL, message.c_str(), "SuperTuxKart - Fatal error", MB_OK);
+    }
+#endif
+
 #endif
 }   // printMessage