Automated software bug localization enabled by meta-heuristic-based convolutional neural network and improved deep neural network

•A new bug localization approach with CDNN using the HGW-SFO algorithm.•Improved deep learning architecture to the bug localization strategy.•Hybrid Grey Wolf-Sun Flower Optimization (HGW-SFO).•The CDNN-based model is superior to the other conventional methods in locating.•HGW-SFO with developed CDNN has done significantly better than others.