CMake未定义符号:pthread_create编译动态库

Question

我的项目以前运行得很好，但为了让它执行自我更新，我将其改为编译为动态库，如下所示：

• 启动器->可执行文件
• 服务器->库(核心项目，带std:：thread的多线程(
• 更新程序->库

现在，在Linux(Debian Bullseye(上，当启动器尝试dlopen服务器库时，我收到一个运行时错误undefined symbol: pthread_create。Windows等效程序运行良好。

我试着把我的大CMakeList分成几个子项目，认为这可能是CMake错误，但这当然不是问题所在。

我在下面包含了服务器和启动器的父级CMakeLists和子项目CMakeList的简化版本。

父级：

################################
# 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")

服务器库子项目：

################################
# 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()

发射器子项目：

################################
# 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 ()

我使用的是CMake 3.16.3和gcc 9.3.0

我做错了什么？我仍然对CMake 不太满意

Answer 1

我已经能够通过添加来解决这个问题

target_link_libraries(${TARGET} pthread)

之后

target_link_libraries(${TARGET} Threads::Threads)

对于启动器，在为Linux编译时。

我需要在启动器中包含<thread>，并有一段代码，如

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

这是非常奇怪的