[commit] Fix "show prompt"

[commit] Fix "show prompt"

[Daniel Jacobowitz]

One of the gcc4 warnings patches incorrectly converted the var_string
case; it's a char **, not a char *.  Committed as obvious, fixes two
testcases on i686-pc-linux-gnu.

-- 
Daniel Jacobowitz
CodeSourcery, LLC

2005-05-28  Daniel Jacobowitz  <dan@codesourcery.com>

	* cli/cli-setshow.c (do_setshow_command): Partially revert previous
	change.  Cast to "char **" for var_string.

Index: cli/cli-setshow.c
===================================================================
RCS file: /cvs/src/src/gdb/cli/cli-setshow.c,v
retrieving revision 1.25
diff -u -p -r1.25 cli-setshow.c
--- cli/cli-setshow.c	26 May 2005 20:49:03 -0000	1.25
+++ cli/cli-setshow.c	28 May 2005 18:16:21 -0000
@@ -301,8 +301,8 @@ do_setshow_command (char *arg, int from_
       switch (c->var_type)
 	{
 	case var_string:
-	  if (((char *)c->var)[0] != '\0')
-	    fputstr_filtered ((char *)c->var, '"', stb->stream);
+	  if (*(char **) c->var)
+	    fputstr_filtered (*(char **) c->var, '"', stb->stream);
 	  break;
 	case var_string_noescape:
 	case var_optional_filename:

Re: [commit] Fix "show prompt"

[Eli Zaretskii]

> Date: Sat, 28 May 2005 14:28:26 -0400
> From: Daniel Jacobowitz <drow@false.org>
> 
> One of the gcc4 warnings patches incorrectly converted the var_string
> case; it's a char **, not a char *.

True.

>        switch (c->var_type)
>  	{
>  	case var_string:
> -	  if (((char *)c->var)[0] != '\0')
> -	    fputstr_filtered ((char *)c->var, '"', stb->stream);
> +	  if (*(char **) c->var)

Doesn't this work without a cast, like this:

	if (*c->var != NULL)

?  I think we should avoid unneeded type-casting.

Re: [commit] Fix "show prompt"

[Daniel Jacobowitz]

On Sun, May 29, 2005 at 09:13:06AM +0300, Eli Zaretskii wrote:
> >        switch (c->var_type)
> >  	{
> >  	case var_string:
> > -	  if (((char *)c->var)[0] != '\0')
> > -	    fputstr_filtered ((char *)c->var, '"', stb->stream);
> > +	  if (*(char **) c->var)
> 
> Doesn't this work without a cast, like this:
> 
> 	if (*c->var != NULL)
> 
> ?  I think we should avoid unneeded type-casting.

No:
    /* Pointer to variable affected by "set" and "show".  Doesn't matter
       if type is not_set.  */
    void *var;

Can't dereference that.  Really, this ought to be replaced with a
union, so that we could eliminate all the casts.

-- 
Daniel Jacobowitz
CodeSourcery, LLC