restrict

In the C programming language, restrict is a type qualifier that can be applied to a pointer to hint to the compiler that for the lifetime of that pointer, no other pointer will be used to access the same pointed-to object. This limits the effects of pointer aliasing, which can allow the compiler to make optimizations (such as vectorization) that would not otherwise be possible. Undefined behaviour results if the declaration of intent is not followed and the object is accessed by an independent pointer.