CMake: Avoid mixed OpenMP linkage

Author: ywwry66

CMakeLists.txt

@@ -117,6 +117,12 @@ if (USE_OPENMP)
   set(CCOMMON_OPT "${CCOMMON_OPT} -DUSE_OPENMP")
   if (NOT NOFORTRAN)
     find_package(OpenMP COMPONENTS Fortran REQUIRED)
+    # Avoid mixed OpenMP linkage
+    get_target_property(OMP_C_LIB OpenMP::OpenMP_C INTERFACE_LINK_LIBRARIES)
+    get_target_property(OMP_Fortran_LIB OpenMP::OpenMP_Fortran INTERFACE_LINK_LIBRARIES)
+    if (NOT OMP_C_LIB STREQUAL OMP_Fortran_LIB)
+      message(FATAL_ERROR "Multiple OpenMP runtime libraries detected. Mixed OpenMP runtime linkage is dangerous. You may pass -DOpenMP_LANG_LIB_NAMES and -DOpenMP_omp_LIBRARY to manually choose the OpenMP library.")
+    endif()
   endif ()
 endif ()
 

ctest/CMakeLists.txt

@@ -44,10 +44,6 @@ else()
     c_${float_char}blas1.c)
 endif()
   target_link_libraries(x${float_char}cblat1 ${OpenBLAS_LIBNAME})
-  if (USE_OPENMP AND (${CMAKE_Fortran_COMPILER_ID} STREQUAL GNU) AND (${CMAKE_C_COMPILER_ID} STREQUAL Clang))
-        string(REGEX REPLACE "-fopenmp" "" CMAKE_Fortran_FLAGS "${CMAKE_Fortran_FLAGS}")
-        target_link_libraries(x${float_char}cblat1 omp pthread)
-  endif()
   if(${CMAKE_SYSTEM_NAME} MATCHES "Linux" OR ${CMAKE_SYSTEM_NAME} MATCHES "FreeBSD" OR ${CMAKE_SYSTEM_NAME} MATCHES "QNX")
       target_link_libraries(x${float_char}cblat1 m)
   endif()
@@ -73,10 +69,6 @@ else()
     constant.c)
 endif()
   target_link_libraries(x${float_char}cblat2 ${OpenBLAS_LIBNAME})
-  if (USE_OPENMP AND (${CMAKE_Fortran_COMPILER_ID} STREQUAL GNU) AND (${CMAKE_C_COMPILER_ID} STREQUAL Clang))
-        string(REGEX REPLACE "-fopenmp" "" CMAKE_Fortran_FLAGS "${CMAKE_Fortran_FLAGS}")
-        target_link_libraries(x${float_char}cblat2 omp pthread)
-  endif()
   if(${CMAKE_SYSTEM_NAME} MATCHES "Linux" OR ${CMAKE_SYSTEM_NAME} MATCHES "FreeBSD" OR ${CMAKE_SYSTEM_NAME} MATCHES "QNX")
     target_link_libraries(x${float_char}cblat2 m)
   endif()
@@ -124,20 +116,12 @@ else()
   endif()
 endif()
   target_link_libraries(x${float_char}cblat3 ${OpenBLAS_LIBNAME})
-  if (USE_OPENMP AND (${CMAKE_Fortran_COMPILER_ID} STREQUAL GNU) AND (${CMAKE_C_COMPILER_ID} STREQUAL Clang))
-        string(REGEX REPLACE "-fopenmp" "" CMAKE_Fortran_FLAGS "${CMAKE_Fortran_FLAGS}")
-        target_link_libraries(x${float_char}cblat3 omp pthread)
-  endif()
   if(${CMAKE_SYSTEM_NAME} MATCHES "Linux" OR ${CMAKE_SYSTEM_NAME} MATCHES "FreeBSD" OR ${CMAKE_SYSTEM_NAME} MATCHES "QNX")
     target_link_libraries(x${float_char}cblat3 m)
   endif()
   if (USE_GEMM3M)
   if ((${float_char} STREQUAL "c") OR (${float_char} STREQUAL "z"))
   target_link_libraries(x${float_char}cblat3_3m ${OpenBLAS_LIBNAME})
-  if (USE_OPENMP AND (${CMAKE_Fortran_COMPILER_ID} STREQUAL GNU) AND (${CMAKE_C_COMPILER_ID} STREQUAL Clang))
-        string(REGEX REPLACE "-fopenmp" "" CMAKE_Fortran_FLAGS "${CMAKE_Fortran_FLAGS}")
-        target_link_libraries(x${float_char}cblat3 omp pthread)
-  endif()
   if(${CMAKE_SYSTEM_NAME} MATCHES "Linux" OR ${CMAKE_SYSTEM_NAME} MATCHES "FreeBSD" OR ${CMAKE_SYSTEM_NAME} MATCHES "QNX")
     target_link_libraries(x${float_char}cblat3_3m m)
   endif()

test/CMakeLists.txt

@@ -34,10 +34,6 @@ endif ()
 foreach(test_bin ${OpenBLAS_Tests})
 	add_executable(${test_bin} ${test_bin}.f)
 target_link_libraries(${test_bin} ${OpenBLAS_LIBNAME})
-if (USE_OPENMP AND (${CMAKE_Fortran_COMPILER_ID} STREQUAL GNU) AND (${CMAKE_C_COMPILER_ID} STREQUAL Clang))
-	string(REGEX REPLACE "-fopenmp" "" CMAKE_Fortran_FLAGS "${CMAKE_Fortran_FLAGS}")
-target_link_libraries(${test_bin} omp pthread)
-endif()
 endforeach()
 
 # $1 exec, $2 input, $3 output_result