re #8418 cppcheck prefomance&style
re #8418 cppcheck style
re #8418 resolve a couple of errors
re #8418 resolve warnings by fixing qtiplot code that never worked
re #8418 resolve warnings by fixing qtiplot code that never worked
re #8418 merge confilcts
Merge remote-tracking branch 'origin/feature/8418_cppcheck_performance'