Question

In C if you have the following code:

for (size_t x, y = someValue; y > 0; y -= x, ptr1 += x, ptr2 += x) 
{
        // do stuff
} 

Will the variable y also be of the type size_t or would it be an int?

Answer 1

a declaration of

int a,b,c;
size_t x,y,z;

means that all of a,b,c are same type (int) as are x,y,z (size_t)

The declaration inside a for-loop is no different — and in your example both x and y are of type size_t

however in your example x is not initialized (only y is set to somevalue) — and unless the body of the loops set it to something you will find that y -= x is going to give you random undefined results.