Re: c/8395: gcc 2.95.4 and 3.2 generate wrong code for double onintel

[Bruce Allen <ballen at gravity dot phys dot uwm dot edu>]

Marco, Tim is also completely correct.

Bruce

On Sat, 2 Nov 2002, Tim Prince wrote:

> On Saturday 02 November 2002 07:42, Marco Bernardo wrote:
> 
> > Let me conclude by saying that my intention is not to be polemic.
> > My point of view is that of a university professor who wants to teach
> > to his students that there is a great alternative to Microsoft,
> > which is Linux and the free software world.
> > You would then understand that it is very difficult for me to support gcc
> > and to teach my students how to use gcc in the presence of such a strange
> > behavior, which is not justifiable at all on a scientific basis.
> >
> >
> From a professorial point of view, you should be encouraging your students to 
> consult expert references on floating point numerics, even if you don't care 
> to do so yourself.  Before you start arguing about IEEE standards and 
> scientific bases, you should be reading up on them, and the technical reasons 
> for including the extended precision option.
> If you are teaching at this level of detail, you could show your students how 
> to set 53-bit rounding mode in order to duplicate the fpu settings of 
> Microsoft compilers, how to use fpu mode settings to test code reliability, 
> and how to break the Microsoft compiler by putting the fpu in standard 
> default mode.  As standard C does not define a function for this purpose, the 
> C committee must not have considered it to be as large an issue as you.
> -- 
> Tim Prince
>