Undefined reference problems - Fortran

Usage
1

My objective is to link my object with the static lib files like

opt/intel/mkl/lib/intel64/libmkl_intel_ilp64.a

opt/intel/mkl/lib/intel64/libmkl_sequential.a

opt/intel/mkl/lib/intel64/libmkl_core.a

I have add some codes in my codes target_link_libraries functions like target_link_libraries(objects MKLROOT.a)

The make command is:

cmake -DBLA_STATIC=ON …（no error）

make install（error）

The error message is:

opt/intel/mkl/lib/intel64/libmkl_core.a(dsytrf.o): In function ‘mkl_lapack_dsytrf’:

dsytrf_gen.f:(.test+0x430): undefined reference to “mkl_lapack_dlasyf”

dsytrf_gen.f:(.test+0x6a5): undefined reference to “mkl_lapack_dlasyf”

opt/intel/mkl/lib/intel64libmkl_core.a(dsygst.o): In function ‘mkl_lapack_dsygst’:

dsygst_gen.f:(.test+0x320): undefined reference to “mkl_blas_dsyr2k”

dsygst_gen.f:(.test+0x675): undefined reference to “mkl_blas_dsyr2k”

…

I have not pasted all error functions. All the errors point to the same static lib file:opt/intel/mkl/intel64/libmkl_core.a.

I have obtained some help from https://www.intel.cn/content/www/cn/zh/developer/tools/oneapi/onemkl-link-line-advisor.html. After many attempts, cmake(cmake -DBLA_STATIC=ON …) and make still exists error.

I am very confused that I have added

-Wl,–start-group

opt/intel/mkl/lib/intel64/libmkl_intel_ilp64.a

opt/intel/mkl/lib/intel64/libmkl_sequential.a

opt/intel/mkl/lib/intel64/libmkl_core.a

-Wl,–end-group

in the function target_link_libraries(object lib) in the CMakeLists.txt of the object file.

Is it possible that I should add the MKLROOT file to other sub-objects linked by the current top-object? In fact I have added the three MKLROOT file into target_link_libraries(sub-objects MKLROOT.a) of all sub-objects. And the error still occurs.

I don’t know what happens and which file should I review or recheck to find the error comes from?

2

Use find_package(MKL CONFIG REQUIRED) and link target MKL::MKL.

This assumes you have oneAPI 2021.3 or newer.

3

I have tried the find_package(MKL CONFIG REQUIRED)

It tell me
"Could not find a package configuration file provided by “MKL” with any of the following names: MKLconfig.cmake or mkl-config.cmake. Add the installation prefix of “MKL” to CMAKE_PREFIX_PATH or set “MKL_DIR” to directory containing one the above file. If “MKL"provides a separate development package or SDK, be sure it has been installed.”

4

My codes will also link dynamic .so files. I want my codes to link the specified static dynamic .a files. It seems that it is invalid to set target_link_libraries(objects MKLROOT.a).

5

Is the Intel oneAPI environment loaded? I.e. did you source setvars.sh? If so, MKLROOT should be set, that is from the Terminal

echo $MKLROOT

Should tell where MKL is installed. If it’s blank, then the oneAPI environment isn’t loaded.

On a Linux system, the default oneMKL setvars.sh location is like “/opt/intel/oneapi/setvars.sh” so I would do from Terminal

source /opt/intel/oneapi/setvars.sh

that must be done in every new Terminal when you want to use oneAPI / oneMKL etc. one of the things that script does is set env var MKLROOT.

That CMake example I linked above prints this from CMake

message(STATUS "ENV{MKLROOT}: $ENV{MKLROOT}")

If that is blank, then “find_package(MKL)” may not succeed.

6

I would choose static or dynamic via the find_package(MKL) and do only

target_link_libraries(myexe PRIVATE MKL::MKL)

Static and dynamic MKL targets required distinct supporting libraries that are encapsulated in imported target MKL::MKL

By the way, that Gist example I linked earlier works on Linux and Windows (and mac)

So following that example, in CMakeLists.txt do like

set(MKL_LINK "static")

find_package(MKL CONFIG REQUIRED)

to find/link static MKL libraries “.a” instead of the default “.so”

7

In my linux system, the oneAPI is not installed. In this case, how can I link the mkl static lib files?

8

I have installed the toolkit oneAPI. It is successful to link the static MKL lib files.

9

However, static MKL lib cannot ensure the accurancy of the results. It seems the results between dynamic and static MKL lib have large difference. I feel confused about that.

10

Do you have an example program I could try? Right the numerical results should be identical shared vs. Dynamic linking.

11

I haven’t tried oneMKL by itself, though it’s certainly possible to do that as a standalone install (e.g. when one wants GCC + MKL on Linux)

12

I have not an example. I will debug through ouputting the middle variables to find what happened. Thank you for helping me solve the static lib linking problem.