CMakeLists.txt

add_library(scsl eigensolvers.c)
set_target_properties (scsl PROPERTIES COMPILE_DEFINITIONS SCSL)
target_link_libraries(scsl multithreading ${LAPACK_LIBS})

add_library(pcsl eigensolvers.c)
set_target_properties (scsl PROPERTIES COMPILE_DEFINITIONS "PCSL=1")
target_link_libraries(pcsl multithreading ${LAPACK_LIBS})

add_library(scpl eigensolvers.c)
set_target_properties (scsl PROPERTIES COMPILE_DEFINITIONS SCPL=1)
target_link_libraries(scpl multithreading ${LAPACK_LIBS})

eigensolvers.c

#ifdef SCSL
    void scsl_bxinv(FileRepresenation* input, FileRepresentation* result)
#elifdef SCPL
    void scpl_bxinv(FileRepresenation* input, FileRepresentation* result)
#elifdef PCSL
    void pcsl_bxinv(FileRepresenation* input, FileRepresentation* result)
#endif
{
 //do stuff
}