https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113277
David Malcolm <dmalcolm at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Ever confirmed|0 |1 Status|UNCONFIRMED |NEW Last reconfirmed| |2024-01-08 --- Comment #1 from David Malcolm <dmalcolm at gcc dot gnu.org> --- Thanks for filing this report. As I understand it, snprintf can accept a NULL destination argument when the size is zero, but otherwise the destination argument must be non-NULL. Hence (as you note), we can't simply add the __nonnull__ attribute to the declaration. Currently the analyzer doesn't have any special-case knowledge of the behavior of sprintf. Looks like we should add it. In particular, looks like we should model the write to the destination buffer (and thus require the non-NULL-ness of the pointer for the known non-zero size case). See also RFE 105102.