CMake引入Dilithium库后函数未定义链接错误求助

作为CMake新手，引入Dilithium库后，能正常使用头文件中的#define变量，但调用库中函数时出现链接错误，相关代码与错误信息如下：

CMakeLists.txt内容 #

cmake_minimum_required(VERSION 3.10)
project(react-native-dilithium VERSION 1.0.0)

include(FetchContent)

FetchContent_Declare(dilithium                              
  GIT_REPOSITORY https://github.com/pq-crystals/dilithium.git
  GIT_TAG        master        
)

FetchContent_MakeAvailable(dilithium)

add_library(dilithium SHARED)
target_sources(dilithium PUBLIC ${dilithium_SOURCE_DIR})
set_target_properties(dilithium PROPERTIES LINKER_LANGUAGE CXX PROPERTIES DILITHIUM_MODE 5 PROPERTIES DILITHIUM_USE_AES TRUE)

add_executable(cpp_test main.cpp)

target_include_directories(cpp_test PUBLIC 
  ${dilithium_BINARY_DIR}
  ${dilithium_SOURCE_DIR}/ref
)


target_link_libraries(cpp_test PUBLIC dilithium)

测试代码 #

#include <iostream>
#include <api.h>

using namespace std;

int main(int argc, char* argv[]) {
    // Message to sign
    const char* message = "This is a message to be signed.";
    size_t message_len = strlen(message);

    // Private key (replace with your actual key)
    unsigned char private_key[pqcrystals_dilithium5aes_ref_SECRETKEYBYTES];

    // Signature buffer (allocate enough space based on parameter set)
    unsigned char signature[pqcrystals_dilithium5aes_ref_BYTES];
    size_t signature_len = sizeof(signature);

    // Call the signing function
    int result = pqcrystals_dilithium5aes_ref_signature(
        signature, &signature_len,
        (const unsigned char*)message, message_len,
        private_key
    );

    return 0;
}

错误信息 #

ld: Undefined symbols:
  pqcrystals_dilithium5aes_ref_signature(unsigned char*, unsigned long*, unsigned char const*, unsigned long, unsigned char const*), referenced from:
      _main in main.cpp.o
clang: error: linker command failed with exit code 1 (use -v to see invocation)
make[2]: *** [cpp_test] Error 1
make[1]: *** [CMakeFiles/cpp_test.dir/all] Error 2
make: *** [all] Error 2

核心问题分析 #

1. 源文件未正确添加：原代码中target_sources(dilithium PUBLIC ${dilithium_SOURCE_DIR})仅指定目录，CMake不会自动递归收集C源文件，导致库中无函数实现的二进制代码。
2. 编译宏定义传递错误：set_target_properties无法传递编译宏（DILITHIUM_MODE、DILITHIUM_USE_AES），这些宏需作为编译定义传递才能生成对应模式的函数符号。
3. C/C++链接兼容性问题：Dilithium是C语言库，C++代码直接调用会因名字修饰导致符号不匹配。
4. 函数名错误：测试代码中调用的pqcrystals_dilithium5aes_ref_signature并非库中实际函数，正确函数名为pqcrystals_dilithium5aes_ref_sign。

修正后的CMakeLists.txt #

cmake_minimum_required(VERSION 3.10)
project(react-native-dilithium VERSION 1.0.0)

include(FetchContent)

FetchContent_Declare(dilithium                              
  GIT_REPOSITORY https://github.com/pq-crystals/dilithium.git
  GIT_TAG        master        
)

FetchContent_GetProperties(dilithium)
if(NOT dilithium_POPULATED)
  FetchContent_Populate(dilithium)
  
  # 收集ref目录下所有C源文件
  file(GLOB DILITHIUM_SRC_FILES "${dilithium_SOURCE_DIR}/ref/*.c")
  
  add_library(dilithium SHARED ${DILITHIUM_SRC_FILES})
  
  # 传递编译宏定义，启用Dilithium 5模式和AES优化
  target_compile_definitions(dilithium PUBLIC DILITHIUM_MODE=5 DILITHIUM_USE_AES)
  
  # 设置库的头文件搜索路径
  target_include_directories(dilithium PUBLIC 
    ${dilithium_SOURCE_DIR}
    ${dilithium_SOURCE_DIR}/ref
  )
endif()

add_executable(cpp_test main.cpp)

# 让测试程序能找到Dilithium头文件
target_include_directories(cpp_test PUBLIC 
  ${dilithium_SOURCE_DIR}/ref
)

# 链接Dilithium库
target_link_libraries(cpp_test PUBLIC dilithium)

修正后的测试代码 #

#include <iostream>
// 用extern "C"包裹C头文件，避免C++名字修饰
extern "C" {
#include <api.h>
}

using namespace std;

int main(int argc, char* argv[]) {
    const char* message = "This is a message to be signed.";
    size_t message_len = strlen(message);

    unsigned char private_key[pqcrystals_dilithium5aes_ref_SECRETKEYBYTES];
    unsigned char public_key[pqcrystals_dilithium5aes_ref_PUBLICKEYBYTES];
    unsigned char signature[pqcrystals_dilithium5aes_ref_BYTES];
    size_t signature_len = sizeof(signature);

    // 先生成密钥对（必须步骤，否则私钥未初始化）
    pqcrystals_dilithium5aes_ref_keypair(public_key, private_key);

    // 调用正确的签名函数
    int result = pqcrystals_dilithium5aes_ref_sign(
        signature, &signature_len,
        (const unsigned char*)message, message_len,
        private_key
    );

    cout << "签名结果：" << (result == 0 ? "成功" : "失败") << endl;
    return 0;
}

关键修正点说明 #

• 手动收集Dilithium的C源文件，确保函数实现被编译进库；
• 使用target_compile_definitions传递编译宏，生成对应模式的函数符号；
• 用extern "C"包裹C头文件，解决C/C++名字修饰不兼容问题；
• 修正函数名为库中实际存在的pqcrystals_dilithium5aes_ref_sign，并补充密钥生成的必要步骤。

内容的提问来源于stack exchange，提问作者Roman