https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77696
--- Comment #11 from David Malcolm <dmalcolm at gcc dot gnu.org> --- (In reply to David Malcolm from comment #5) > I brainstormed some ideas on making these kinds of warning easier for > the user to understand. A simple example where the overflowing write is to the start of the buffer: sprintf of an unbounded string to a fixed-size buf[100]: demo.c:6:3: note: buffer overflow... snprintf of "%s" from: |+------+|+--------------++-------+| ||0...99|||100...strlen-1|| strlen|| || ||| || NUL || |+------+|+--------------++-------+| vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv |<--ok-->|<-- overflow -->| | | | to 'buf': | | |+------+| ||0...99|| |+------+|