Libguestfs - Dec 2014 - index-parse.c:1256:6: error: assuming pointer wraparound does not occur when comparing P +- C1 with P +- C2 [-Werror=strict-overflow]

No idea why this happens:

index-parse.y: In function 'yyparse':
index-parse.c:1256:6: error: assuming pointer wraparound does not occur when
comparing P +- C1 with P +- C2 [-Werror=strict-overflow]
   if (yyss + yystacksize - 1 <= yyssp)
      ^

It only happens on one machine, and not on any others, even
though they have similar versions of gcc and bison installed.

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
virt-builder quickly builds VMs from scratch
http://libguestfs.org/virt-builder.1.html

On Mon, Dec 15, 2014 at 05:54:51PM +0000, Richard W.M. Jones
wrote:
> No idea why this happens:
> 
> index-parse.y: In function 'yyparse':
> index-parse.c:1256:6: error: assuming pointer wraparound does not occur
when comparing P +- C1 with P +- C2 [-Werror=strict-overflow]
>    if (yyss + yystacksize - 1 <= yyssp)
>       ^
> 
> It only happens on one machine, and not on any others, even
> though they have similar versions of gcc and bison installed.
I should clarify ..  Of course I understand what the error message
means and why it happens.  The mystery is that it only happens on a
single machine, and not on other nearly identical machines.

If someone else sees this, let me know ...

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
libguestfs lets you edit virtual machines.  Supports shell scripting,
bindings from many languages.  http://libguestfs.org

On Mon, Dec 15, 2014 at 06:42:08PM +0000, Richard W.M. Jones
wrote:
> On Mon, Dec 15, 2014 at 05:54:51PM +0000, Richard W.M. Jones wrote:
> > No idea why this happens:
> > 
> > index-parse.y: In function 'yyparse':
> > index-parse.c:1256:6: error: assuming pointer wraparound does not
occur when comparing P +- C1 with P +- C2 [-Werror=strict-overflow]
> >    if (yyss + yystacksize - 1 <= yyssp)
> >       ^
> > 
> > It only happens on one machine, and not on any others, even
> > though they have similar versions of gcc and bison installed.
> 
> I should clarify ..  Of course I understand what the error message
> means and why it happens.  The mystery is that it only happens on a
> single machine, and not on other nearly identical machines.
I've solved this now.  See 2162d09b2c9e138779d95f1fc7c3409765a5a40c.

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
virt-top is 'top' for virtual machines.  Tiny program with many
powerful monitoring features, net stats, disk stats, logging, etc.
http://people.redhat.com/~rjones/virt-top