[Bug fortran/29975] [meta-bugs] ICEs with CP2K

["jv244 at cam dot ac dot uk" <gcc-bugzilla at gcc dot gnu dot org>]

------- Comment #114 from jv244 at cam dot ac dot uk  2007-06-21 03:41 -------
(In reply to comment #113)
> Great. I hope we can get it working with MPI (should probably already work) 

I suspect that will be no real problem, but I do not have an MPI/gfortran setup
to check.

> > this seems quite good (despite being 10-15% slower)
> 
> Indeed, this is not so bad. Do you use external libraries?

yes, linked against lapack/blas (gotoblas and mkl respectively), but the input
is tuned so that this is a negligable fraction of the total time.

> 
> > For the first benchmark
> > most of the slowdown seems to be in one part of the code (core_hamiltonian),
> > for which gfortran is about 35% slower (I suspect the difference comes from one
> > subroutine ai_overlap_new).
> 
> Is that related to PR31021 or PR31079?
> 

No, I haven't made a testcase for this, this takes a lot of time.

> > with an out of memory error at '-O1 -fbounds-check'.
> 
> Yup, -fbounds-check for code with lots of array access has a high cost, 

single file package, but see PR 32439 for details.


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29975