Finding and analyzing compiler warning defects

Good compiler diagnostic warnings facilitate software development as they indicate likely programming mistakes or code smells. However, due to compiler bugs, the warnings may be erroneous, superfluous or missing, even for mature production compilers like GCC and Clang. In this paper, we (1) propose the first randomized differential testing technique to detect compiler warning defects and (2) describe our extensive evaluation in finding warning defects in widely-used C compilers.