CMake 未定義符號：pthread_create 編譯動態庫

Question

我的項目之前運行良好，但我將其更改為編譯為動態庫，以便讓它執行自我更新，如下所示：

• 啟動器 -> 可執行文件
• 服務器 -> 庫（核心項目，帶 std::thread 的多線程）
• 更新程序 -> 庫

現在，在 Linux (Debian Bullseye) 上，當啟動器嘗試 dlopen 服務器庫時，我得到一個運行時錯誤undefined symbol: pthread_create 。 Windows 等效工作正常。

我嘗試將我的大 CMakeLists 拆分為幾個子項目，認為這可能是 CMake 錯誤，但這當然不是問題。

我在下面包含了服務器和啟動器的父 CMakeLists 和子項目 CMakeLists 的簡化版本。

家長：

################################
# Project settings
################################
cmake_minimum_required (VERSION 3.8)

set(TARGET_NAME "Server")
set(SERVER_VERSION "1.0.0")

set(CMAKE_TRY_COMPILE_TARGET_TYPE "STATIC_LIBRARY")
project(${TARGET_NAME} VERSION ${SERVER_VERSION} DESCRIPTION "My Server")

set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/bin)
set(CMAKE_LIBRARY_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/bin)

################################
# Sources
################################
configure_file(
    ${CMAKE_SOURCE_DIR}/src/Resource.h
    ${CMAKE_CURRENT_BINARY_DIR}/src/Resource.h
    COPYONLY)
configure_file(
    ${CMAKE_SOURCE_DIR}/src/Resource.rc.in
    ${CMAKE_CURRENT_BINARY_DIR}/src/Resource.rc
    @ONLY)
set_source_files_properties("../Server.ico" PROPERTIES LANGUAGE RC)

include_directories("includes")

################################
# Subprojects
################################
add_subdirectory("src/Server")
add_subdirectory("src/Launcher")
add_subdirectory("src/Updater")

服務器庫子項目：

################################
# Project settings
################################
cmake_minimum_required (VERSION 3.8)

set(TARGET_NAME "Server-Core")
if (LIB)
    set(EXE_NAME "ServerCore")
else ()
    set(EXE_NAME "Server")
endif ()

project(${TARGET_NAME} VERSION ${SERVER_VERSION} DESCRIPTION "My Server")

################################
# Sources
################################
configure_file(
    Server.hh.in
    Server.hh
    @ONLY)

include_directories(. "${CMAKE_BINARY_DIR}/src/Server/")

file(GLOB_RECURSE SRC "*.hh" "*.hpp" "*.cpp" "${CMAKE_BINARY_DIR}/src/*.hh")
if (LIB)
    add_library(${TARGET_NAME} SHARED ${SRC})
elseif (WIN32)
    add_executable(${TARGET_NAME} ${SRC} ${CMAKE_BINARY_DIR}/src/Resource.rc)
else ()
    add_executable(${TARGET_NAME} ${SRC})
endif ()

################################
# Libs
################################
set(THREADS_PREFER_PTHREAD_FLAG ON)
find_package(Threads REQUIRED)
target_link_libraries(${TARGET_NAME} Threads::Threads)

if(WIN32)
    target_link_libraries(${TARGET_NAME} wsock32 ws2_32)
    target_link_libraries(${TARGET_NAME} Crypt32)
    target_link_libraries(${TARGET_NAME} ${CMAKE_SOURCE_DIR}/libs/libssl.lib)
    target_link_libraries(${TARGET_NAME} ${CMAKE_SOURCE_DIR}/libs/libcrypto.lib)
elseif(UNIX)
    target_link_libraries(${TARGET_NAME} -static-libgcc -static-libstdc++)
    target_link_libraries(${TARGET_NAME} ${CMAKE_SOURCE_DIR}/libs/libssl.a)
    target_link_libraries(${TARGET_NAME} ${CMAKE_SOURCE_DIR}/libs/libcrypto.a)
endif()

################################
# Compiler settings
################################

set_target_properties(${TARGET_NAME} PROPERTIES VERSION ${SERVER_VERSION})
set_target_properties(${TARGET_NAME} PROPERTIES PREFIX "")

set_property(TARGET ${TARGET_NAME} PROPERTY CXX_STANDARD 20)
set_property(TARGET ${TARGET_NAME} PROPERTY CXX_STANDARD_REQUIRED ON)
set_property(TARGET ${TARGET_NAME} PROPERTY OUTPUT_NAME ${EXE_NAME})

if(MSVC)
    target_compile_options(${TARGET_NAME} PUBLIC /std:c++latest)
    target_compile_options(${TARGET_NAME} PUBLIC /Zc:__cplusplus)
    set(CMAKE_EXE_LINKER_FLAGS    "${CMAKE_EXE_LINKER_FLAGS} /MANIFEST:NO")
endif()

啟動器子項目：

################################
# Project settings
################################
cmake_minimum_required (VERSION 3.8)

set(LAUNCHER_TARGET "Launcher")
set(LAUNCHER_EXE_NAME "Server")
set(LAUNCHER_VERSION "1.0.0")

project(${LAUNCHER_TARGET} VERSION ${LAUNCHER_VERSION} DESCRIPTION "My Server")

################################
# Sources
################################
if (LIB)
    file(GLOB_RECURSE SRC "*.hh" "*.hpp" "*.cpp"
        "../Server/Utils/DynamicLibrary/DynamicLibraryWindows.cpp" "../Server/Utils/DynamicLibrary/DynamicLibraryLinux.cpp"
        "../Server/Utils/DynamicLibrary/IDynamicLibrary.cpp")

    if (WIN32)
        add_executable(${LAUNCHER_TARGET} ${SRC} ${CMAKE_BINARY_DIR}/src/Resource.rc)
    else ()
        add_executable(${LAUNCHER_TARGET} ${SRC})
    endif ()
endif ()

################################
# Libs
################################

if (UNIX)
    if (LIB)
        target_link_libraries(${LAUNCHER_TARGET} ${CMAKE_DL_LIBS})
    endif ()
endif ()

################################
# Compiler settings
################################

set(THREADS_PREFER_PTHREAD_FLAG ON)
find_package(Threads REQUIRED)
target_link_libraries(${LAUNCHER_TARGET} Threads::Threads)

if (LIB)
    set_target_properties(${LAUNCHER_TARGET} PROPERTIES VERSION ${LAUNCHER_VERSION})

    set_property(TARGET ${LAUNCHER_TARGET} PROPERTY CXX_STANDARD 20)
    set_property(TARGET ${LAUNCHER_TARGET} PROPERTY CXX_STANDARD_REQUIRED ON)
    set_property(TARGET ${LAUNCHER_TARGET} PROPERTY OUTPUT_NAME ${LAUNCHER_EXE_NAME})
endif ()

我正在使用 CMake 3.16.3 和 gcc 9.3.0

我做錯了什么？ 我仍然對 CMake 不太滿意

Answer 1

我已經能夠通過添加來解決問題

target_link_libraries(${TARGET} pthread)

后

target_link_libraries(${TARGET} Threads::Threads)

對於啟動器，在編譯 Linux 時。

我需要在啟動器中包含<thread>並有一段代碼，例如

std::thread t([](){});
t.join();

這非常奇怪