[Solved] GCC/G++ different attitudes for: void* to int [closed]

Question

int k = (int *)arg;
this statement can not compaile with G++,But GCC only Warning,why?

It doesn’t compile in C++ because int* is not implicitly convertible to int and therefore the statement is ill-formed.

// int k=*(int *)arg;
why this statement not right?

That statement is syntactically well-formed in C++. But arg doesn’t point to an int object (or object of compatible type), so the behaviour of indirecting through the pointer is undefined.

Accepted Answer

int k = (int *)arg;
this statement can not compaile with G++,But GCC only Warning,why?

It doesn’t compile in C++ because int* is not implicitly convertible to int and therefore the statement is ill-formed.

// int k=*(int *)arg;
why this statement not right?

That statement is syntactically well-formed in C++. But arg doesn’t point to an int object (or object of compatible type), so the behaviour of indirecting through the pointer is undefined.