http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52952
--- Comment #9 from dodji at seketeli dot org <dodji at seketeli dot org> 2012-05-24 18:38:40 UTC --- "manu at gcc dot gnu.org" <gcc-bugzi...@gcc.gnu.org> a écrit: > So either one keeps track of all source locations of all "interesting" > characters within strings, which sounds infeasible. Or one needs to > re-preprocess the format string, creating new locations on-the-fly. Dodji, is > this possible? With the current infrastructure, I fear we cannot re-process the format string *after* the initial pre-processing phase is done, to create new locations that we'd a in the line maps. However, briefly looking at the source code, we might be able to pull this whole shebang off, in a way. I am thinking that in gcc/c-family/c-format.c:check_format_info_main, we can arrange for the instance of format_kind_info (that is the result of parsing the format string) to carry the virtual location of the beginning of the format string *and* the offset of the relevant character we might want to warn about. Then, later the routines that trigger the warning by analyzing the instance of format_kind_info could be passed the relevant location for the beginning of the of the format string as well as the byte offset of the relevant character I talked about above. At warning type, it could re-construct the exact column where of that relevant character, with its byte offset and the virtual location of the beginning of the format string. Does that make sense?
