Re: [Valgrind-users] No "Use of uninitialised value" warning

[André W. <Woe...@on...>]

On Wednesday 13 May 2009, Nicholas Nethercote wrote:
> On Wed, May 13, 2009 at 2:43 AM, Colin Miller 
<col...@pi...> wrote:
> > André Wöbbeking wrote:
> >
> > Valgrind only reports when an unused variable is used for
> > flow-control (or, hopefuly I/O).
> >
> > Swapping doesn't trigger the alert. This is because, in C,
> > structures can legitimately have
> > uninitialised areas due to nested unions or padding.
>
> There's more on this in the manual.  And this blog post discusses it
> in even more detail:
>
> http://blog.mozilla.com/nnethercote/2009/02/27/eliminating-undefined-
>values-with-valgrind-the-easy-way/

Thanks.

Now back to my problem. The original code has double instead of int (I 
just tried both types to be sure and forgot to change back) and on MSVC 
std::swap() of uninitialised doubles triggers a floating point exception 
(if enabled) as MSVC uses the FPU.

I was really surprised that the code crashes on WIndows as it runs fine 
under valgrind on Linux.


Cheers,
André