clang、openMP和CMake [英] clang, openMP and CMake

问题描述

我在使用cmake生成简单的openMP代码时遇到问题。

我已经安装了clang-omp，可以使用clang-omp -fopenmp filename.c

编译该程序

我已经尝试了很多次来制作CMakeLists.txt文件，但是没有结果！ 在我包含的文件中：

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()

我尝试通过调用：

告诉CMake使用该编译器

CC=clang-omp CXX=clang-omp++ cmake 

和没有。

两种情况下的结果如下：

-- Try OpenMP C flag = [-fopenmp=libomp]
-- Performing Test OpenMP_FLAG_DETECTED
-- Performing Test OpenMP_FLAG_DETECTED - Failed
-- 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 = [-fopenmp=libomp]
-- 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 /Applications/CMake.app/Contents/share/cmake-3.5/Modules/FindPackageHandleStandardArgs.cmake:148 (message):
  Could NOT find OpenMP (missing: OpenMP_C_FLAGS OpenMP_CXX_FLAGS)
Call Stack (most recent call first):
  /Applications/CMake.app/Contents/share/cmake-3.5/Modules/FindPackageHandleStandardArgs.cmake:388 (_FPHSA_FAILURE_MESSAGE)
  /Applications/CMake.app/Contents/share/cmake-3.5/Modules/FindOpenMP.cmake:234 (find_package_handle_standard_args)
  CMakeLists.txt:4 (FIND_PACKAGE)

推荐答案

添加非系统clang(对于我来说，LLVM4.0)的问题在于您必须添加Include和lib目录。llvm-config在我的情况下正确拾取它们，但CMake没有使用它们。

假设您的PATH可以，并且您已经设置了CC和CXX，则需要添加：

export C_INCLUDE_PATH=$(llvm-config --includedir)
export CPLUS_INCLUDE_PATH=$(llvm-config --includedir)
export LIBRARY_PATH=$(llvm-config --libdir)

如果您更喜欢Lmod，此.lua文件应该可以：

help([[
This is the module file for the llvm and clang compiler.
]])

local version = "4.0"

whatis("Name: LLVM")
whatis("Version: " .. version)
whatis("Keywords: System, Compiler")
whatis("URL: http://www.llvm.org/")
whatis("Description: LLVM compiler family")

family("compiler")

local prefix = "/work/llvm"

prepend_path("PATH", pathJoin(prefix, "bin"))
setenv("CC",  pathJoin(prefix, "bin/clang"))
setenv("CXX", pathJoin(prefix, "bin/clang++"))
setenv("C_INCLUDE_PATH", pathJoin(prefix, "include"))
setenv("CPLUS_INCLUDE_PATH", pathJoin(prefix, "include"))
setenv("LIBRARY_PATH", pathJoin(prefix, "lib"))
prepend_path("DYLD_LIBRARY_PATH", pathJoin(prefix, "lib"))

(这是针对Mac，将DYLD更改为LD针对Linux)

此功能与CMake配合使用很好，它可以拾取-fopenmp。手动编译也只需要一个标志。

这篇关于clang、openMP和CMake的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！