Fix a crash in CUSTOM_TYPE Windows native file save dialogs

Fixed bugs:
  - https://bugs.launchpad.net/inkscape/+bug/1639701

1 files changed, 6 insertions, 6 deletions

diff --git a/src/ui/dialog/filedialogimpl-win32.cpp b/src/ui/dialog/filedialogimpl-win32.cpp
index 1efec7d52..6c8ce2620 100644
--- a/src/ui/dialog/filedialogimpl-win32.cpp
+++ b/src/ui/dialog/filedialogimpl-win32.cpp
@@ -1685,28 +1685,28 @@ void FileSaveDialogImplWin32::addFileType(Glib::ustring name, Glib::ustring patt
 
     knownExtensions.clear();
 
-    int extension_index = 0;
-    int filter_length = 1;
-
-    ustring all_exe_files_filter = pattern;
     Filter all_exe_files;
 
     const gchar *all_exe_files_filter_name = name.data();
+    const gchar *all_exe_files_filter = pattern.data();
 
     // Calculate the amount of memory required
     int filter_count = 1;
-
+    int filter_length = 1;
 
     // Filter Executable Files
     all_exe_files.name = g_utf8_to_utf16(all_exe_files_filter_name,
         -1, NULL, &all_exe_files.name_length, NULL);
-    all_exe_files.filter = g_utf8_to_utf16(all_exe_files_filter.data(),
+    all_exe_files.filter = g_utf8_to_utf16(all_exe_files_filter,
             -1, NULL, &all_exe_files.filter_length, NULL);
     all_exe_files.mod = NULL;
     filter_list.push_front(all_exe_files);
+    
+    filter_length = all_exe_files.name_length + all_exe_files.filter_length + 3; // Add 3 for two \0s and a *
 
     knownExtensions.insert( Glib::ustring(all_exe_files_filter).casefold() );
 
+    int extension_index = 0;
     _extension_map = new Inkscape::Extension::Extension*[filter_count];
 
     _filter = new wchar_t[filter_length];