[Bug tree-optimization/64277] [4.9/5.0 Regression] Incorrect warning "array subscript is above array bounds"

[izamyatin at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64277

--- Comment #5 from Igor Zamyatin <izamyatin at gmail dot com> ---
BTW, making nc and m to be int instead short eliminates the warning