Cmake 找不到带有神秘错误消息的 Threads 包

Question

我正在尝试使用以下 CMakeLists.txt 进行配置:

cmake_minimum_required(VERSION 3.2)                                                                                                    
project(MotionBlow CXX)
find_package(Threads REQUIRED)                                                                                                     
find_package(Boost COMPONENTS system program_options REQUIRED)                                                                     
include(gtest.cmake)

add_executable(motionBlow src/blow.cpp)
target_include_directories(motionBlow PUBLIC include)
target_link_libraries(motionBlow RTIMULib ${Boost_LIBRARIES})
set_property(TARGET motionBlow PROPERTY CXX_STANDARD 14)

add_executable(chat_client src/chat_client.cpp)
target_include_directories(chat_client PUBLIC include)
target_link_libraries(chat_client ${Boost_LIBRARIES} Threads::Threads)
set_property(TARGET chat_client PROPERTY CXX_STANDARD 14)

add_executable(chat_server src/chat_server.cpp)
target_include_directories(chat_server PUBLIC include)
target_link_libraries(chat_server ${Boost_LIBRARIES} Threads::Threads)
set_property(TARGET chat_server PROPERTY CXX_STANDARD 14)

enable_testing()

add_executable(matrixTest test/MatrixTest.cpp src/Matrix.cpp)
target_include_directories(matrixTest PUBLIC include ${GTEST_INCLUDE_DIR})
target_link_libraries(matrixTest ${GTEST_LIBRARY} Threads::Threads)
set_property(TARGET matrixTest PROPERTY CXX_STANDARD 14)

在 ubunutu 16.04 上它工作正常，但是在带有 Raspbian 8.0/Cmake 3.6.2 的 raspberry pi 和 ubuntu 15.10/Cmake 3.2.2 上我得到

CMake Error at /usr/share/cmake-3.2/Modules/FindPackageHandleStandardArgs.cmake:138 (message):
  Could NOT find Threads (missing: Threads_FOUND)
Call Stack (most recent call first):
  /usr/share/cmake-3.2/Modules/FindPackageHandleStandardArgs.cmake:374 (_FPHSA_FAILURE_MESSAGE)
  /usr/share/cmake-3.2/Modules/FindThreads.cmake:204 (FIND_PACKAGE_HANDLE_STANDARD_ARGS)
  CMakeLists.txt:4 (find_package)

不幸的是，错误日志仅包含以下内容:

Determining if files pthread.h exist failed with the following output:

Source:
/* */
#include <pthread.h>


int main(void){return 0;}

所以我不知道如何解决这个问题。有任何想法吗？我的 CMakelists.txt 是否丢失了某些东西，或者我应该得到一个丢失的包？

Answer 1

使用你的代码我可以重现你的错误，这似乎是一个后续错误:

-- Looking for include file pthread.h
CMake Error at /usr/share/cmake-3.2/Modules/CheckIncludeFiles.cmake:74 (try_compile):
  Unknown extension ".c" for file
  try_compile() works only for enabled languages.  Currently these are:

    CXX

  See project() command to enable other languages.

两种可能的解决方案:

1. 将 C 添加到您的项目语言中:

   project(MotionBlow C CXX)
   

2. 将 .c 扩展名添加到有效的 C++ 文件中:

   MotionBlowMakeRulesOverwrite.cmake

   list(APPEND CMAKE_CXX_SOURCE_FILE_EXTENSIONS c)
   

   CMakeLists.txt

   cmake_minimum_required(VERSION 3.2)
   set(CMAKE_USER_MAKE_RULES_OVERRIDE "MotionBlowMakeRulesOverwrite.cmake")
   project(MotionBlow CXX)
   

如果这些都不起作用，请检查是否安装了 pthread:

sudo apt-get install libpthread-stubs0-dev

引用资料

• > Tell CMake to use C++ compiler for C files coming from CMake?
• > Unable to locate package pthread