Prevent assert (and access violation) in wxWidgets.

(It directly dereferences the ArrayString with the
FilterIndex, without bounds checking it.)

gerbview/files.cpp

@@ -142,7 +142,12 @@ bool GERBVIEW_FRAME::LoadFileOrShowDialog( const wxString& aFileName,
 
         wxFileDialog dlg( this, dialogTitle, currentPath, filename.GetFullName(), dialogFiletypes,
                           wxFD_OPEN | wxFD_FILE_MUST_EXIST | wxFD_MULTIPLE | wxFD_CHANGE_DIR );
-        dlg.SetFilterIndex( lastGerberFileWildcard );
+
+        wxArrayString dummy1, dummy2;
+        const int nWildcards = wxParseCommonDialogsFilter( dialogFiletypes, dummy1, dummy2 );
+
+        if( lastGerberFileWildcard >= 0 && lastGerberFileWildcard < nWildcards )
+            dlg.SetFilterIndex( lastGerberFileWildcard );
 
         if( dlg.ShowModal() == wxID_CANCEL )
             return false;

pcbnew/footprint_libraries_utils.cpp

@@ -114,6 +114,7 @@ FOOTPRINT* FOOTPRINT_EDIT_FRAME::ImportFootprint( const wxString& aName )
         }
 
         wxString allWildcardsStr;
+
         for( const wxString& wildcard : allWildcardsSet )
             allWildcardsStr << wildcard;
 
@@ -123,7 +124,11 @@ FOOTPRINT* FOOTPRINT_EDIT_FRAME::ImportFootprint( const wxString& aName )
         wxFileDialog dlg( this, _( "Import Footprint" ), m_mruPath, wxEmptyString, fileFiltersStr,
                           wxFD_OPEN | wxFD_FILE_MUST_EXIST );
 
-        dlg.SetFilterIndex( lastFilterIndex );
+        wxArrayString dummy1, dummy2;
+        const int nWildcards = wxParseCommonDialogsFilter( fileFiltersStr, dummy1, dummy2 );
+
+        if( lastFilterIndex >= 0 && lastFilterIndex < nWildcards )
+            dlg.SetFilterIndex( lastFilterIndex );
 
         if( dlg.ShowModal() == wxID_CANCEL )
             return nullptr;