Compiling groops with custon LAPACK installation

[AndreHauschild]

Dear groops community,

for testing purposes I had to compile groops with a LAPACK version other than the system version. I would like to share the necessary modifications to CMakeList.txt here, because it might be of interest for other users as well.

Assuming that you have downloaded the LAPACK source files and compiled them in $(HOME)/Software/, you must set the path to the libraries like so

set(HOME_DIR $ENV{HOME})
set(LAPACK_DIR "${HOME_DIR}/Software/lapack-3.12.0")
set(BLAS_LIBRARIES "${LAPACK_DIR}/librefblas.a")
set(LAPACK_LIBRARIES "${LAPACK_DIR}/liblapack.a;-lm;-ldl")

and comment out the search for the system libraries

#find_package(BLAS   REQUIRED)
#find_package(LAPACK REQUIRED)

Then, also change the order of the library inclusion to avoid linker errors

set(BASE_LIBRARIES ${LAPACK_LIBRARIES} ${BLAS_LIBRARIES} ${EXPAT_LIBRARIES} stdc++fs)

Here is a snippet of the relevant part of CMakeList.txt with all the changes:

# External Source Files
# ---------------------
# HWM14     Horizontal Wind Model 2014 (https://map.nrl.navy.mil/map/pub/nrl/HWM/HWM14/)
# NRLMSIS   NRLMSIS 2.0 thermospheric model (https://map.nrl.navy.mil/map/pub/nrl/NRLMSIS/NRLMSIS2.0/)
# JB2008    JB2008 thermospheric model (http://sol.spacenvironment.net/jb2008/)
# IGRF      International Geomagnetic Reference Field (https://doi.org/10.1186/s40623-015-0228-9)
# IERS      International Earth Rotation and Reference Systems Service (IERS) Conventions software collection (https://iers-conventions.obspm.fr/)

# Specify the full paths to the custom BLAS and LAPACK libraries
set(HOME_DIR $ENV{HOME})
set(LAPACK_DIR "${HOME_DIR}/Software/lapack-3.12.0")
set(BLAS_LIBRARIES "${LAPACK_DIR}/librefblas.a")
set(LAPACK_LIBRARIES "${LAPACK_DIR}/liblapack.a;-lm;-ldl")

#find_package(BLAS   REQUIRED)
#find_package(LAPACK REQUIRED)
find_package(EXPAT  REQUIRED)
include_directories(${EXPAT_INCLUDE_DIRS})

set(BASE_LIBRARIES ${LAPACK_LIBRARIES} ${BLAS_LIBRARIES} ${EXPAT_LIBRARIES} stdc++fs)

Hope this helps!

[Hanbing59]

Hi Andre,

thanks for your sharing.

From you post

also change the order of the library inclusion to avoid linker errors

just out of curiosity, why should we use a different order for the library inclusion when using custom LAPACK/BLAS library?

[AndreHauschild]

Hi Hanbing,

admittedly I do not know the reason, but it turned out to be necessary to avoid linker errors.

[Hanbing59]

Hmm, interesting.