Re: [Qemu-devel] [PATCH v2 0/3] Fix strncpy() warnings for GCC8 new -Wstringop-truncation

[Michael S. Tsirkin]

On Tue, Dec 18, 2018 at 05:38:17PM +0100, Paolo Bonzini wrote:
> On 18/12/18 15:54, Michael S. Tsirkin wrote:
> > On Tue, Dec 18, 2018 at 03:45:08PM +0100, Paolo Bonzini wrote:
> >> On 18/12/18 15:31, Michael S. Tsirkin wrote:
> >>> Do you happen to know why does it build fine with
> >>> Gcc 8.2.1?
> >>>
> >>> Reading the GCC manual it seems that
> >>> there is a "nostring" attribute that means
> >>> "might not be 0 terminated".
> >>> I think we should switch to that which fixes the warning
> >>> but also warns if someone tries to misuse these
> >>> as C-strings.
> >>>
> >>> Seems to be a better option, does it not?
> >>>
> >>>
> >>
> >> Using strpadcpy is clever and self-documenting, though.  We have it
> >> already, so why not use it.
> >>
> >> Paolo
> > 
> > The advantage of nonstring is that it will catch attempts to
> > use these fields with functions that expect a 0 terminated string.
> > 
> > strpadcpy will instead just silence the warning.
> 
> Ah, I see.  We could also do both, that's a matter of taste.
> 
> Paolo

Do you happen to know how to make gcc check the buffer size
for strpadcpy? Is the name strncpy just hard-coded?

-- 
MST