Re: [Qemu-devel] [PATCH v2] Fix compilation of check-qint.c by using a long long integer constant

[Pierre Riteau]

On 5 sept. 2009, at 10:07, Reimar Döffinger wrote:

> On Fri, Sep 04, 2009 at 03:25:20PM -0300, Luiz Capitulino wrote:
> > On Fri, 4 Sep 2009 19:56:30 +0200
> > Pierre Riteau <address@hidden> wrote:
> >
> > > On 4 sept. 09, at 19:29, Reimar Döffinger wrote:
> > >
> > > > On Fri, Sep 04, 2009 at 07:09:58PM +0200, Pierre Riteau wrote:
> > > > > Error was:
> > > > > check-qint.c:46: error: integer constant is too large for 'long'  
> > > > > type
> > > > > ---
> > > > > check-qint.c |    2 +-
> > > > > 1 files changed, 1 insertions(+), 1 deletions(-)
> > > > >
> > > > > diff --git a/check-qint.c b/check-qint.c
> > > > > index ae5d22f..f5c054e 100644
> > > > > --- a/check-qint.c
> > > > > +++ b/check-qint.c
> > > > > @@ -43,7 +43,7 @@ END_TEST
> > > > > START_TEST(qint_from_int64_test)
> > > > > {
> > > > >    QInt *qi;
> > > > > -    const int64_t value = 0xffffffffffffffff;
> > > > > +    const int64_t value = 0xffffffffffffffffLL;
> > > >
> > > > Hm, well it does not really fit in a signed long long either (so
> > > > from that
> > > > aspect it should be ULL).
> > > > Should it not be simply -1 (does qemu assume all architectures
> > > > use two's complement?)?
> > >
> > >
> > > How about INT64_MIN?
> >
> > The test is there to assure that QInt can handle
> > integers > 32-bits, so it's not an issue if we have
> > fewer bits.
>
> For that this value is nonsense, this test could succeed even with a  
> 32
> bit QInt and sign expansion.
> Not to mention that also a conversion to float and back would keep the
> value unchanged, although it would lose information in the general  
> case.
> If it's supposed to test that it will really store 64 bit it should be
> some random number with variation in both upper and lower bits.


Very good point.
I sent a new patch to the list.

--
Pierre Riteau -- http://perso.univ-rennes1.fr/pierre.riteau/