The following built-in functions allow performing simple arithmetic operations together with checking whether the operations overflowed.
These built-in functions promote the first two operands into infinite precision signed type and perform addition on those promoted operands. The result is then cast to the type the third pointer argument points to and stored there. If the stored result is equal to the infinite precision result, the built-in functions return false, otherwise they return true. As the addition is performed in infinite signed precision, these built-in functions have fully defined behavior for all argument values.
The first built-in function allows arbitrary integral types for operands and the result type must be pointer to some integer type, the rest of the built-in functions have explicit integer types.
The compiler will attempt to use hardware instructions to implement these built-in functions where possible, like conditional jump on overflow after addition, conditional jump on carry etc.
These built-in functions are similar to the add overflow checking built-in functions above, except they perform subtraction, subtract the second argument from the first one, instead of addition.
These built-in functions are similar to the add overflow checking built-in functions above, except they perform multiplication, instead of addition.