warning: comparison of unsigned expression >= 0 is always true

Question

I have the following error when compiling a C file:

t_memmove.c: In function ‘ft_memmove’:
ft_memmove.c:19: warning: comparison of unsigned expression >=          


        

Answer 1

If you subtract two unsigned integers in C, the result will be interpreted as unsigned. It doesn't automatically treat it as signed just because you subtracted. One way to fix that is use n >= i instead of n - i >= 0.