Understanding Strict Aliasing - CellPerformance

One pointer is said to alias another pointer when both refer to the same location or object. In this example, 0uint32_t 1swap_words( uint32_t arg ) 2{ 3 uint16_t* const sp = (uint16_t*)&arg; 4 uint16_t hi = sp[0]; 5 uint16_t lo = sp[1]; 6 7 sp[1] = hi; 8 sp[0] = lo; 9 10 return (arg); 11} The memory referred to by sp is an alias of arg because they refer to the same address in memory. In C99, it i