Re: d3dx9_36: Silence an uninitialized compiler warning (GCC 8).

[Paul Gofman]

There is actually no usage of uninitialized variable there, though 
it is probably not exactly straightforward for compiler to guess. Why it 
does not complain that 'cdesc[index]' may be used uninitialized while it 
is handled the same way? AFAIK GCC 8 is not released yet, maybe this 
will change before final release?

If still to change that, does the attached patch fixes the warning 
as well (sorry, I don't have gcc 8 in hands to test)? If yes, I would 
suggest that would be a tiny bit nicer way to silence the warning.

On 11/07/2017 01:22 AM, Gerald Pfeifer wrote:
> There are more of this in d3dx9_36, but at least this is one down.
>
> Gerald
> Signed-off-by: Gerald Pfeifer
>
> dlls/d3dx9_36/preshader.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/dlls/d3dx9_36/preshader.c b/dlls/d3dx9_36/preshader.c
> index e3e91c643b..ed22dc4045 100644
> --- a/dlls/d3dx9_36/preshader.c
> +++ b/dlls/d3dx9_36/preshader.c
> @@ -888,7 +888,7 @@ static HRESULT get_constants_desc(unsigned int *byte_code, struct d3dx_const_tab
>       for (i = 0; i < desc.Constants; ++i)
>       {
>           unsigned int index = out->input_count;
> -
>    WORD constantinfo_reserved;
> -
>    WORD constantinfo_reserved = 0;
>
>     hc = ID3DXConstantTable_GetConstant(ctab, NULL, i);
>     if (!hc)

d3dx9_36: Silence an uninitialized compiler warning (GCC 8).

[Matteo Bruni]

2017-11-08 10:33 GMT+01:00 Paul Gofman :
> There is actually no usage of uninitialized variable there, though it is
>
> probably not exactly straightforward for compiler to guess. Why it does not
> complain that 'cdesc[index]' may be used uninitialized while it is handled
> the same way? AFAIK GCC 8 is not released yet, maybe this will change before
> final release?
> If still to change that, does the attached patch fixes the warning as
>
> well (sorry, I don't have gcc 8 in hands to test)? If yes, I would suggest
> that would be a tiny bit nicer way to silence the warning.

If that works it would be preferable to me too.

d3dx9_36: Silence an uninitialized compiler warning (GCC 8).

[Gerald Pfeifer]

On Wed, 8 Nov 2017, Paul Gofman wrote:
> There is actually no usage of uninitialized variable there, though it is 
> probably not exactly straightforward for compiler to guess. Why it does 
> not complain that 'cdesc[index]' may be used uninitialized while it is 
> handled the same way?

Yes, I did not find this really being used uninitialized (and, yes,
you're right, it actually does complain about cdesc[index] as well
-- those were the other warnings I referred to, where I did not have
a fix/workaround yet).
> If still to change that, does the attached patch fixes the warning as well
> (sorry, I don't have gcc 8 in hands to test)? If yes, I would suggest that
> would be a tiny bit nicer way to silence the warning.

Yes, it does, plus -- unlike my patch -- it also addresses the other
warnings, so indeed it's also more effective.

On Wed, 8 Nov 2017, Matteo Bruni wrote:
> If that works it would be preferable to me too.

Same here. :-)  Can we go with your patch, Paul?

Thanks,
Gerald

d3dx9_36: Silence an uninitialized compiler warning (GCC 8).

[Paul Gofman]

On 11/09/2017 11:39 PM, Gerald Pfeifer wrote:
> If that works it would be preferable to me too.
> Same here. :-)  Can we go with your patch, Paul?
>
> Thanks,
> Gerald

Yes, sure, you can use it any way you like.

d3dx9_36: Silence an uninitialized compiler warning (GCC 8).

[Paul Gofman]

On 11/09/2017 11:39 PM, Gerald Pfeifer wrote:
> On Wed, 8 Nov 2017, Paul Gofman wrote:
> > There is actually no usage of uninitialized variable there, though it is
> > probably not exactly straightforward for compiler to guess. Why it does
> > not complain that 'cdesc[index]' may be used uninitialized while it is
> > handled the same way?
>
> Yes, I did not find this really being used uninitialized (and, yes,
> you're right, it actually does complain about cdesc[index] as well
> -- those were the other warnings I referred to, where I did not have
> a fix/workaround yet).

I suppose cdesc[index] can be zeroed on error in the same function which 
fills it, but in my understanding the wined3d style did not approve 
redundant zero initializations (unless I missed anything here), 
including auto variables and redundant HEAP_ZERO_MEMORY flag to 
HeapAlloc(). So what should happen now to the code already there and new 
patches if gcc 8 starts issuing this warning false positive? Could it be 
just a bug which will be fixed in gcc maybe?

d3dx9_36: Silence an uninitialized compiler warning (GCC 8).

[Matteo Bruni]

2017-11-09 23:12 GMT+01:00 Paul Gofman :
> On 11/09/2017 11:39 PM, Gerald Pfeifer wrote:
> > On Wed, 8 Nov 2017, Paul Gofman wrote:
> > > There is actually no usage of uninitialized variable there, though it is
> > > probably not exactly straightforward for compiler to guess. Why it does
> > > not complain that 'cdesc[index]' may be used uninitialized while it is
> > > handled the same way?
> >
> > Yes, I did not find this really being used uninitialized (and, yes,
> > you're right, it actually does complain about cdesc[index] as well
> > -- those were the other warnings I referred to, where I did not have
> > a fix/workaround yet).
>
> I suppose cdesc[index] can be zeroed on error in the same function which
> fills it, but in my understanding the wined3d style did not approve
> redundant zero initializations (unless I missed anything here), including
> auto variables and redundant HEAP_ZERO_MEMORY flag to HeapAlloc(). So what
> should happen now to the code already there and new patches if gcc 8 starts
> issuing this warning false positive? Could it be just a bug which will be
> fixed in gcc maybe?

If I understood Gerald's email correctly, those other warnings are
also fixed by your patch. BTW, could you please send it as a proper
patch to wine-patches? It would be helpful :)