GFortran 44 optimizations and Intel SSE4

[Jacob Anderson]

Sure enough, when I added "-O3" to the options, I got the reference errors:

undefined reference to `std::basic_ostream<char, std::char_traits<char> >&
std::__ostream_insert<char, std::char_traits<char>
>(std::basic_ostream<char, std::char_traits<char> >&, char const*, long)'

undefined reference to `std::ctype<char>::_M_widen_init() const'

etc ...

Is there a special library that I need to use when compiling with -O3 and
gfortran44/gcc44?


> -----Original Message-----
> From: fortran-owner@gcc.gnu.org [mailto:fortran-owner@gcc.gnu.org] On
> Behalf Of Jacob Anderson
> Sent: Tuesday, November 01, 2011 1:55 PM
> To: fortran@gcc.gnu.org
> Subject: RE: GFortran 44 optimizations and Intel SSE4
> 
> I was able to build the mvapich2 library using my optimizations. When I
> tried to build an executable with said optimizations, I got:
> 
> undefined reference to `std::ctype<char>::_M_widen_init() const
> 
> If I remove the optimization options:
> 
>   -march=native -msse4.2 -maes -O3 -funroll-loops --param max-unroll-
> times=4
> 
> Then it links the executable just fine.
> 
> It would see, without any credible evidence though, that using the
> native architecture optimizations causes some incompatibilities....
> 
> I am experimenting with the different options to find out which one
> causes the link error.
> 
> -- Jake
> 
> 
> > -----Original Message-----
> > From: fortran-owner@gcc.gnu.org [mailto:fortran-owner@gcc.gnu.org] On
> > Behalf Of Tim Prince
> > Sent: Tuesday, November 01, 2011 11:05 AM
> > To: fortran@gcc.gnu.org
> > Subject: Re: GFortran 44 optimizations and Intel SSE4
> >
> > On 11/1/2011 12:42 PM, Jacob Anderson wrote:
> > > Hi,
> > >
> > > Thanks for the responses! Yes, I did mean the "-Ox" generic options.
> > >
> > > We are compiling against Intel X5670 and X5620, so no desktop
> > architectures.  The "SSE4.2" extensions are of interest for their
> > vector capabilities. Is there any online documentation on the
> > optimization algorithms used when the SSE4 optimizations are enabled?
> > >
> > > We are using gfortran44 version 4.4.4 20100726:
> > >
> > > GNU Fortran (GCC) 4.4.4 20100726 (Red Hat 4.4.4-13) Copyright (C)
> > > 2010 Free Software Foundation, Inc.
> > >
> > > Thanks
> > >
> > > -- jake
> > >
> > >
> > >
> > >> -----Original Message-----
> > >> From: fortran-owner@gcc.gnu.org [mailto:fortran-owner@gcc.gnu.org]
> > >> On Behalf Of Tim Prince
> > >> Sent: Tuesday, November 01, 2011 9:28 AM
> > >> To: fortran@gcc.gnu.org
> > >> Subject: Re: GFortran 44 optimizations and Intel SSE4
> > >>
> > >> On 11/1/2011 11:42 AM, Jacob Anderson wrote:
> > >>
> > >>>
> > >>> Does the general optimization option to gfortran44 include Intel
> > >>> SSE4
> > >> optimizations (4.1 AND 4.2)?
> > >>>
> > >>
> > >> Perhaps that's not what you meant to ask? By general, do you mean
> > >> generic (definitely not including -msse4)?
> > >>
> > >> http://gcc.gnu.org/onlinedocs/gcc-4.4.6/gcc/i386-and-x86_002d64-
> > >> Options.html#i386-and-x86_002d64-Options
> > >>
> > >> -msse4.1 and -msse4.2 are listed there.
> > >>
> > >>    -mtune=barcelona , which you might use for Core I7 (with or
> > >> without -msse4), if you don't want to use a current gfortran, is
> > listed there.
> > >>
> > >> --
> >
> > Oh, just in case, auto-vectorization is enabled either by setting -O3
> > or by adding -ftree-vectorize to the options list at -O2 or -O1.  For
> > myself, I've got improved results on the Xeon 5500 and 5600 series by
> > adding -funroll-loops --param max-unroll-times=4
> >
> >
> > --
> > Tim Prince
>