[Bug middle-end/101134] Bogus -Wstringop-overflow warning about non-existent overflow

["dangelog at gmail dot com" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101134

--- Comment #13 from Giuseppe D'Angelo <dangelog at gmail dot com> ---
Hi,

(In reply to Martin Sebor from comment #12)
> So in general, the distinction between the two cases can only be made when
> it can be discerned from the IL, and the IL doesn't always preserve the
> conditional nature of the problem statement.  So every warning must always
> be viewed as a "maybe" kind of a warning.  It will never be a sure a thing,
> either at the scope of individual functions, and certainly not with inlining
> or function cloning.

I think there's been a misunderstanding. Apologies if I created confusion, let
me try and reset the conversation:

I perfectly understand if, in the context of this particular warning (or any
other similar middle-end warning), it is very hard, or currently impossible, or
even always impossible to distinguish between the "maybe" case and the
"certain" case. 

Without such a distinction available or possible, I'm also OK with raising 
false positives. Therefore, in relation to this aspect of the original
submission (the code raising a false positive warning), I'm perfectly fine at
marking the request of not triggering the warning altogether as out of scope /
won't fix / etc.


On other hand, I was not OK with the idea that the *warning message* should
keep saying that "there *is* an overflow", in a positive indicative mood. All
I'd really ask there would be to reword the message in order to say something
like "there *may be* an overflow" instead. It might seem like a trivial/useless
change for someone who knows how the middle-end works and where such warnings
come from, but it would bring a lot of clarity to end-users (to me, at least)
if any warning message would clearly indicate whether it may be a false
positive. And that could be achieved by simply adding "may" to the warning
messages in question.

Does this make sense?

Thanks,