Re: pointer-to-pointer (invalid lvalue in unary `&)

From: Chris Fogelklou (chris.fogelklou_at_comhem.se)
Date: 04/04/04 

Date: Sun, 04 Apr 2004 17:04:08 GMT

> That doesn't seem very fruitful advice. He'd be better off trying to
> understand the type system than trying to learn how to circumvent it.
>
Yep.

>>changing your debugging process from finding a syntax
> > error to figuring out why your computer is crashing :)
>
> Finding the syntax error is much easier

Hence the smiley and the statement that he would have to figure out why the
computer is crashing (sarcasm... oops... my bad :)

> > pointer = (struct example_struct **pointer)&ex_ptr;
>
> That cast is badly-formed, and requires a diagnostic.

Hmm... It compiles on my system... but from the other posts/responses I've
been participating in, I think my system might be broken. Could you please
elaborate?

typedef struct ui_tag {
  uint16 i;
  uint16 j;
  uint16 k;
  uint16 l;
} ui_t, *pui_t;

void main(void)
{
  struct ui_tag * ptr_ui;
  struct ui_tag ** pptr_ui;
  struct ui_tag ui = {0,0,0,0};

  ptr_ui = &ui;
  pptr_ui = (struct ui_tag **)&ptr_ui;
  while(1);

}

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