https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105523
--- Comment #31 from LIU Hao <lh_mouse at 126 dot com> --- (In reply to Andrew Pinski from comment #24) > The warning is there for the above case really (and similar ones with struct > offsets). Where you originally have a null pointer and have an offset from > there; by the time the warning happens, the IR does not know if it was > originally from an offset of a null pointer or if the value was written in. I understand that completely, but it does not justify the confusion. Something like 'warning: array subscript 0 is outside array bounds of' says nothing about null pointers, and is thus misleading. It is addition of a non-zero offset to a null pointer that the warning really belongs to.
