// We exclude the trivial case where a sliding piece does in two moves what
// it could do in one move: eg. Ra1a2, Ra2a3.
if ( m2to == m1from
- || (m1to == m2from && !squares_aligned(m1from, m2from, m2to)))
+ || (m1to == m2from && !aligned(m1from, m2from, m2to)))
return true;
// Second one moves through the square vacated by first one