[FFmpeg-devel] [PATCH] Fix MSVC warnings about possible value truncation.

[Reimar Döffinger]

On 03.09.2014, at 02:16, Peter Kasting <pkasting at google.com> wrote:
> On Tue, Sep 2, 2014 at 5:10 PM, wm4 <nfxjfg at googlemail.com> wrote:
> 
>>> In the end, if we do decide to enable this warning, we will have to
>> insert
>>> some casts that are clearly safe, e.g.
>>> 
>>>  if (x > INT_MAX)
>>>    return;
>>>  int y = (int)x;
>>> 
>>> Indeed, if all of the nontrivial issues are fixed, those sorts of casts
>> are
>>> presumably the majority of the trivial changes we'd have to introduce.
>> 
>> And here is exactly where we disagree.
> 
> 
> I'm not sure what you mean by "disagree".  I would assume you mean you
> don't think we should enable the warning if it would mean having to insert
> any casts like this, but that's not actually disagreeing with me, that's
> just a statement that the benefit isn't worth the costs.  Or do you mean
> you actually disagree that deciding to enable the warning would require
> inserting casts?  I'm confused.

I suspect similar to me he means that maybe we shouldn't enable warnings the compiler doesn't support well enough to manage to avoid trivial and obvious false positives...
In other words, there should maybe be some effort compiler-side first, or alternatively the check would better be provided by a more advanced tool.