| __builtin_return_address

| Getting the Return or Frame Address of a Function | Next

`void *__builtin_return_address (int level);`
This function returns the return address of the current function, or of one of its callers. The level argument is number of frames to scan up the call stack. A value of `0` yields the return address of the current function, a value of `1` yields the return address of the caller of the current function, and so forth. When inlining the expected behavior is that the function will return the address of the function that will be returned to. To work around this behavior use the `noinline` function attribute.
The level argument must be a constant integer.
Sometimes (especially without a frame pointer) it may be impossible to determine the return address of any function other than the current one; in such cases, or when the top of the stack has been reached, this function will return a random value. In addition, __builtin_frame_address may be used to determine if the top of the stack has been reached.
This function should be used with a nonzero argument only for debugging purposes.