https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88814
--- Comment #3 from Martin Sebor <msebor at gcc dot gnu.org> --- (In reply to Dávid Bolvanský from comment #2) The n in the assignment in 'd[n - 1] = 0;' should be the result of snprintf for constant arguments. In GCC, it's computed by the sprintf pass which then performs other substitutions based on it.