Re: [Lapackpp-devel] Error configuring with externally compiled Blas & Lapack

[Christian S. <sti...@tu...>]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

(copying to list as well)

Sonia Singhal schrieb:
> Ya I just saw that. HEre is what it reads.
> ----------------------------------------------------------------------
> configure:22164: checking for sgemm_ in
> /scratch2/sonia/packages/mkl/lib/32/libmkl_ia32.a
> configure:22197: gcc -o conftest -g -O2   conftest.c
> /scratch2/sonia/packages/mkl/lib/32/libmkl_ia32.a
> -L/afs/ece.cmu.edu/support/gcc/4.1.1/4.1.1-1/i386_suse93/image/usr/local/bin/../lib/gcc/i686-pc-linux-gnu/4.1.1
>
> -L/afs/ece.cmu.edu/support/gcc/4.1.1/4.1.1-1/i386_suse93/image/usr/local/bin/../lib/gcc
>
> -L/usr/local/lib/gcc/i686-pc-linux-gnu/4.1.1
> -L/afs/ece.cmu.edu/support/gcc/4.1.1/4.1.1-1/i386_suse93/image/usr/local/bin/../lib/gcc/i686-pc-linux-gnu/4.1.1/../../..
>
> -L/usr/local/lib/gcc/i686-pc-linux-gnu/4.1.1/../../.. -lgfortranbegin
> -lgfortran -lm -lgcc_s >&5
> /scratch2/sonia/packages/mkl/lib/32/libmkl_ia32.a(def_sgemm_omp.o): In
> function `mkl_blas_def_sgemm':
> tmp_sgemm_omp.c:(.text+0x1e): undefined reference to
> `__kmpc_global_thread_num'
> tmp_sgemm_omp.c:(.text+0xe0): undefined reference to `omp_in_parallel'
> ...

Then you're in (some) trouble. This means that if a program links to
MKL's libmkl_ia32.a, it *must* also link to various other libraries that
contain these functions. In the documentation of Intel's MKL library it
should say something along these lines:

"If a program wants to use the functions from MKL blas, it must link to
the libraris libfoo, libbla, and libpoo",

In which case you should write the full linker arguments into the
- --with-blas or --with-lapack parameters, like so:

     ./configure --with-blas="-L/my/mkl/dir/lib/32 -lmkl_ia32 -lfoo
- -lbla -lpoo"

(If you specify a library to the linker with the "-l" [ell] argument,
you say the library name without leading "lib" and without trailing
".so" or ".a".)

Keep adding more libraries until the full error message in config.log
doesn't complain anymore about "undefined reference" in any function of
the installed library.

Regards,

Christian
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.2.1 (MingW32)
Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org

iQCVAwUBRbjHEGXAi+BfhivFAQIrqwP/Tu+IxCKC9l63s8yRy1W+aCNwNDp8mblX
wxcYFiSFr5EjeyYNjsG3nAnDmxQ9soUynl81vBusbnP/FBlWfT1O/o0SfGIppmyn
B9whdDI5/Fhh1wFOpn4tB2TX004gGKP6I97UvjY1XrEvKWeI4guGzjnFcpoDK1FR
d6lUwhRNsLQ=
=jMjP
-----END PGP SIGNATURE-----