I don't know, those warnings look pretty pedantic. In projects I help maintain, we've found the gnulib manywarnings module to be more useful.
- Turn on compiler warnings by default for AC_PROG_CC, AC_PROG_... Dale Visser
- Re: Turn on compiler warnings by default for AC_PROG_CC,... Paul Eggert
- Re: Turn on compiler warnings by default for AC_PROG_CC,... Visser, Dale