Developer Guide

  • 2021.1
  • 12/04/2020
  • Public Content

Using MKL_DIRECT_CALL in Fortran Applications

The following examples of code and link lines show how to activate direct calls to
Intel® oneAPI Math Kernel Library
kernels in Fortran applications:
  • Include
    , to be preprocessed by the Fortran compiler preprocessor
    # include "" program DGEMM_MAIN .... * Call Intel MKL DGEMM .... call sub1() stop 1 end * A subroutine that calls DGEMM subroutine sub1 * Call Intel MKL DGEMM end
  • For multi-threaded
    Intel® oneAPI Math Kernel Library
    , compile with
    option for Intel Fortran compiler and with
    preprocessor macro:
    ifort –DMKL_DIRECT_CALL –fpp your_application.f -Wl,--start-group $(MKLROOT)/lib/intel64/libmkl_intel_lp64.a $(MKLROOT)/lib/intel64/libmkl_core.a $(MKLROOT)/lib/intel64/libmkl_intel_thread.a -Wl,--end-group -lpthread –lm -openmp -I$(MKLROOT)/include
  • To use
    Intel® oneAPI Math Kernel Library
    in the sequential mode, compile with
    option for Intel Fortran compiler (or with
    for PGI compilers) and with
    preprocessor macro:
    ifort –DMKL_DIRECT_CALL_SEQ –fpp your_application.f -Wl,--start-group $(MKLROOT)/lib/intel64/libmkl_intel_lp64.a $(MKLROOT)/lib/intel64/libmkl_core.a $(MKLROOT)/lib/intel64/libmkl_sequential.a -Wl,--end-group -lpthread –lm -I$(MKLROOT)/include
Optimization Notice
Intel's compilers may or may not optimize to the same degree for non-Intel microprocessors for optimizations that are not unique to Intel microprocessors. These optimizations include SSE2, SSE3, and SSSE3 instruction sets and other optimizations. Intel does not guarantee the availability, functionality, or effectiveness of any optimization on microprocessors not manufactured by Intel. Microprocessor-dependent optimizations in this product are intended for use with Intel microprocessors. Certain optimizations not specific to Intel microarchitecture are reserved for Intel microprocessors. Please refer to the applicable product User and Reference Guides for more information regarding the specific instruction sets covered by this notice.
Notice revision #20110804

Product and Performance Information


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