Failure of implicit real*8

[Steve Kargl]

On Sun, Feb 20, 2011 at 02:13:35AM +0000, Michael D. Berger wrote:
> Using:
>    gfortran44 -fdefault-real-8
> 
> where:
>    [~]$ gfortran44 --version
>    GNU Fortran (GCC) 4.4.0 20090514 (Red Hat 4.4.0-6)
> 
> I have two nearly identical subroutines very similar to:
> 
>    subroutine orderRows(mx, idxSort, nrows, ncols)
>    dimension idxSort(nrows),mx(nrows,ncols),tmp(nrows,ncols)
>    ...
> 
> where mx is expected to be real, in particular, real*8 because
> of the compile option.
> 
> But one of the two interprets mx as an integer, giving
> radically wrong results.
> 
> Using, instead:
> 
>    subroutine orderRows(mx, idxSort, nrows, ncols)
>    dimension idxSort(nrows)
>    real mx(nrows,ncols),tmp(nrows,ncols)
>    ...
> 
> produces correct results.
> 
> I compiler bug?
> 

Are you serious?  There is too little information here
to even guess at an answer.  Show us the actual code.

Well, I do have guess, but you won't care for it.
Don't use -fdefault-real-8, because this option 
may not do what you think it does.

-- 
Steve