Re: [AD] Type-pun warnings with GCC 4.1

[Peter Wang <tjaden@xxxxxxxxxx>]

On 2006-07-02, Chris <chris.kcat@xxxxxxxxxx> wrote:
> When building the latest SVN from SF using GCC 4.1.1, I get some type-pun 
> warnings when compiling dat.c and grabber.c (which would invariably cause 
> failure with --enable-strictwarn). The attached patch fixes dat.c,

You can commit those if they work.

> but 
> grabber.c may prove to be a little trickier. For reference, the lines are 
> 516, 1743, and 3271. The first of which is below:
> 
> static void get_selection_info(DATAFILE **dat, DATAFILE ***parent)
> {
>    if ((SELECTED_ITEM <= 0) || (SELECTED_ITEM >= data_count)) {
>       *dat = NULL;
>       *parent = &datafile;
>    }
>    else {
>       *dat = data[SELECTED_ITEM].dat;
>       if ((*dat)->type == DAT_FILE)
>      *parent = (DATAFILE **)&(*dat)->dat; // error here!
>       else
>      *parent = data[SELECTED_ITEM].parent;
>    }
> }

If a better way is not found, it appears squeezing in an intermediate
cast to (void *) disables the warnings, e.g.
     *parent = (DATAFILE **) (void *) &(*dat)->dat; // error here!

Peter