c++ - Cmake 不适用于 Maverick 上的 openMP

Question

我正在使用 OpenMP 编写并行代码。这是我案例中使用的 CMakeLists 的一部分。

FIND_PACKAGE( OpenMP REQUIRED)
    if(OPENMP_FOUND)
    message("OPENMP FOUND")
    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${OpenMP_CXX_FLAGS}")
    set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} ${OpenMP_EXE_LINKER_FLAGS}")
    endif()

但是，当我们启动 cmake .. 时，它似乎没有找到 OpenMP 包，我得到了这个错误

Try OpenMP C flag = [ ]
-- Performing Test OpenMP_FLAG_DETECTED
-- Performing Test OpenMP_FLAG_DETECTED - Failed
-- Try OpenMP C flag = [-fopenmp]
-- Performing Test OpenMP_FLAG_DETECTED
-- Performing Test OpenMP_FLAG_DETECTED - Failed
-- Try OpenMP C flag = [/openmp]
-- Performing Test OpenMP_FLAG_DETECTED
-- Performing Test OpenMP_FLAG_DETECTED - Failed
-- Try OpenMP C flag = [-Qopenmp]
-- Performing Test OpenMP_FLAG_DETECTED
-- Performing Test OpenMP_FLAG_DETECTED - Failed
-- Try OpenMP C flag = [-openmp]
-- Performing Test OpenMP_FLAG_DETECTED
-- Performing Test OpenMP_FLAG_DETECTED - Failed
-- Try OpenMP C flag = [-xopenmp]
-- Performing Test OpenMP_FLAG_DETECTED
-- Performing Test OpenMP_FLAG_DETECTED - Failed
-- Try OpenMP C flag = [+Oopenmp]
-- Performing Test OpenMP_FLAG_DETECTED
-- Performing Test OpenMP_FLAG_DETECTED - Failed
-- Try OpenMP C flag = [-qsmp]
-- Performing Test OpenMP_FLAG_DETECTED
-- Performing Test OpenMP_FLAG_DETECTED - Failed
-- Try OpenMP C flag = [-mp]
-- Performing Test OpenMP_FLAG_DETECTED
-- Performing Test OpenMP_FLAG_DETECTED - Failed
-- Try OpenMP CXX flag = [ ]
-- Performing Test OpenMP_FLAG_DETECTED
-- Performing Test OpenMP_FLAG_DETECTED - Failed
-- Try OpenMP CXX flag = [-fopenmp]
-- Performing Test OpenMP_FLAG_DETECTED
-- Performing Test OpenMP_FLAG_DETECTED - Failed
-- Try OpenMP CXX flag = [/openmp]
-- Performing Test OpenMP_FLAG_DETECTED
-- Performing Test OpenMP_FLAG_DETECTED - Failed
-- Try OpenMP CXX flag = [-Qopenmp]
-- Performing Test OpenMP_FLAG_DETECTED
-- Performing Test OpenMP_FLAG_DETECTED - Failed
-- Try OpenMP CXX flag = [-openmp]
-- Performing Test OpenMP_FLAG_DETECTED
-- Performing Test OpenMP_FLAG_DETECTED - Failed
-- Try OpenMP CXX flag = [-xopenmp]
-- Performing Test OpenMP_FLAG_DETECTED
-- Performing Test OpenMP_FLAG_DETECTED - Failed
-- Try OpenMP CXX flag = [+Oopenmp]
-- Performing Test OpenMP_FLAG_DETECTED
-- Performing Test OpenMP_FLAG_DETECTED - Failed
-- Try OpenMP CXX flag = [-qsmp]
-- Performing Test OpenMP_FLAG_DETECTED
-- Performing Test OpenMP_FLAG_DETECTED - Failed
-- Try OpenMP CXX flag = [-mp]
-- Performing Test OpenMP_FLAG_DETECTED
-- Performing Test OpenMP_FLAG_DETECTED - Failed
CMake Error at /opt/local/share/cmake-3.3/Modules/FindPackageHandleStandardArgs.cmake:148 (message):
  Could NOT find OpenMP (missing: OpenMP_C_FLAGS OpenMP_CXX_FLAGS)

这是CMakeLists.txt

cmake_minimum_required(VERSION 2.6)

#Declaration du projet

project(MYfirstcamke)

set(EXECUTABLE_OUTPUT_PATH bin/${CMAKE_BUILD_TYPE})

#Inclusion de opencv

include_directories(/usr/local/include/)

link_directories(/usr/local/lib)

FIND_PACKAGE( OpenMP REQUIRED)
if(OPENMP_FOUND)
message("OPENMP FOUND")
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${OpenMP_CXX_FLAGS}")
set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} ${OpenMP_EXE_LINKER_FLAGS}")
endif()

find_package(PCL 1.2 REQUIRED)
include_directories(${PCL_INCLUDE_DIRS})
link_directories(${PCL_LIBRARY_DIRS})
add_definitions(${PCL_DEFINITIONS})

file(

    GLOB_RECURSE

    source_files

    src/*


)
#declaration de l'executable

add_executable(

my_executable

${source_files}

)
#Configuration de l'edition de lien.
target_link_libraries(

my_executable opencv_core  opencv_imgproc opencv_video opencv_highgui ${PCL_LIBRARIES}


)

我该如何解决？我确定已安装 openMPi 并且它位于 opt/local/include

Answer 1

OpenMP 和 MPI 是两个完全不同的东西。

OMP 需要编译器支持，在 OS X 上你需要通过 Homebrew . (您也可以通过 Homebrew 安装 MPI，这很好)。

brew install clang-omp

安装 clang-omp 后，您可以像这样调用它来告诉 CMake 使用该编译器。

CC=clang-omp CXX=clang-omp++ cmake <insert your normal cmake parameters here>