[Bug tree-optimization/78969] bogus snprintf truncation warning due to missing range info

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78969

--- Comment #8 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
idx_10 addition is a consequence of TODO_update_ssa in vrp1's todo_flags,
triggered by jump threading creating the bb6.