在 CMake 中为 CPLEX 传递链接器标志

问题描述

简而言之：我无法将使用 CPLEX 的程序与 CMake 链接起来，链接器似乎没有找到 CPLEX 库 (cplex)，但找到了其他一些库 (ilocplex) #include <ilcplex/ilocplex.h> int main(int argc,char *argv[]) { IloEnv env; IloModel model(env); IloCplex cplex(model); return 0; } ）。从命令行，它确实有效。

详细：

对于使用 CPLEX 的程序：

CMakeLists.txt

我有以下cmake_minimum_required(VERSION 3.17) project(myprog C CXX) set(CMAKE_EXPORT_COMPILE_COMMANDS ON) set(CMAKE_CXX_STANDARD 17) set(CMAKE_CXX_STANDARD_REQUIRED ON) set(CMAKE_POSITION_INDEPENDENT_CODE ON) set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} ${CMAKE_CURRENT_SOURCE_DIR}/cmake) find_package(CPLEX) if (CPLEX_FOUND) add_definitions(-DIL_STD) else() message (FATAL_ERROR "CPLEX not found!") endif() add_executable(myprog src/main.cpp ) target_include_directories(myprog PUBLIC ${CPLEX_INCLUDE_DIRS}) target_link_libraries(myprog PUBLIC ${CPLEX_LIBRARIES}) set_target_properties(myprog PROPERTIES LINK_FLAGS "-lconcert -lilocplex -lcplex -lpthread -ldl") ：

cmake/FindCPLEX.cmake

和set (CPLEX_DIR "/opt/ibm/ILOG/CPLEX_Studio_Community201") if (CPLEX_INCLUDE_DIR) set(CPLEX_FOUND TRUE) set(CPLEX_INCLUDE_DIRS "${CPLEX_INCLUDE_DIR};${CPLEX_CONCERT_INCLUDE_DIR}" ) set(CPLEX_LIBRARIES "${CPLEX_ILO_LIBRARY};${CPLEX_CONCERT_LIBRARY};${CPLEX_LIBRARY};${CPLEX_PTHREAD_LIBRARY}" ) else (CPLEX_INCLUDE_DIR) find_path(CPLEX_INCLUDE_DIR NAMES ilcplex/cplex.h PATHS "${CPLEX_DIR}/cplex/include" ) find_path(CPLEX_INCLUDE_ILCPLEX NAMES cplex.h PATHS "${CPLEX_DIR}/cplex/include/ilcplex" ) find_path(CPLEX_CONCERT_INCLUDE_DIR NAMES ilconcert/ilomodel.h PATHS "${CPLEX_DIR}/concert/include" ) find_path(CPLEX_INCLUDE_ILCONCERT NAMES ilomodel.h PATHS "${CPLEX_DIR}/concert/include/ilconcert" ) find_library(CPLEX_LIBRARY cplex PATHS "${CPLEX_DIR}/cplex/lib/x86-64_sles10_4.1/static_pic" "${CPLEX_DIR}/cplex/lib/x86-64_darwin/static_pic/" "${CPLEX_DIR}/cplex/lib/x86-64_linux/static_pic" ) find_library(CPLEX_ILO_LIBRARY ilocplex PATHS "${CPLEX_DIR}/cplex/lib/x86-64_sles10_4.1/static_pic" "${CPLEX_DIR}/cplex/lib/x86-64_darwin/static_pic/" "${CPLEX_DIR}/cplex/lib/x86-64_linux/static_pic" ) find_library(CPLEX_CONCERT_LIBRARY concert PATHS "${CPLEX_DIR}/concert/lib/x86-64_linux/static_pic/" "${CPLEX_DIR}/concert/lib/x86-64_sles10_4.1/static_pic" "${CPLEX_DIR}/concert/lib/x86-64_darwin/static_pic/" ) find_library( CPLEX_PTHREAD_LIBRARY pthread PATHS "/usr/lib" "/usr/lib64" "/lib" "/lib64" ) find_library( CPLEX_DL_LIBRARY dl PATHS "/usr/lib" "/usr/lib64" "/lib" "/lib64" ) set(CPLEX_COMPILER_FLAGS "-DIL_STD" CACHE STRING "Cplex Compiler Flags") include(FindPackageHandleStandardArgs) find_package_handle_standard_args(CPLEX DEFAULT_MSG CPLEX_LIBRARY CPLEX_INCLUDE_DIR CPLEX_CONCERT_INCLUDE_DIR CPLEX_ILO_LIBRARY CPLEX_CONCERT_LIBRARY) if(CPLEX_FOUND) set(CPLEX_INCLUDE_DIRS "${CPLEX_INCLUDE_DIR};${CPLEX_CONCERT_INCLUDE_DIR};${CPLEX_INCLUDE_ILCPLEX};${CPLEX_INCLUDE_ILCONCERT}" ) set(CPLEX_LIBRARIES ${CPLEX_CONCERT_LIBRARY} ${CPLEX_ILOCPLEX_LIBRARY} ${CPLEX_LIBRARY} ${CPLEX_PTHREAD_LIBRARY} ${CPLEX_DL_LIBRARY}) endif(CPLEX_FOUND) mark_as_advanced(CPLEX_INCLUDE_DIR CPLEX_LIBRARY CPLEX_CONCERT_INCLUDE_DIR CPLEX_ILO_LIBRARY CPLEX_CONCERT_LIBRARY CPLEX_PTHREAD_LIBRARY) endif(CPLEX_INCLUDE_DIR) message(STATUS "CPLEX_ILO_LIBRARY=${CPLEX_ILO_LIBRARY}") message(STATUS "CPLEX_LIBRARIES=${CPLEX_LIBRARIES}") message(STATUS "CPLEX_INCLUDE_DIRS=${CPLEX_INCLUDE_DIRS}") message(STATUS "concert=${concert}") message(STATUS "cplex=${cplex}") ：

-- Found CPLEX: /opt/ibm/ILOG/CPLEX_Studio_Community201/cplex/lib/x86-64_linux/static_pic/libcplex.a  
-- CPLEX_ILO_LIBRARY=/opt/ibm/ILOG/CPLEX_Studio_Community201/cplex/lib/x86-64_linux/static_pic/libilocplex.a
-- CPLEX_LIBRARIES=/opt/ibm/ILOG/CPLEX_Studio_Community201/concert/lib/x86-64_linux/static_pic/libconcert.a;/opt/ibm/ILOG/CPLEX_Studio_Community201/cplex/lib/x86-64_linux/static_pic/libcplex.a;/usr/lib/x86_64-linux-gnu/libpthread.so;/usr/lib/x86_64-linux-gnu/libdl.so
-- CPLEX_INCLUDE_DIRS=/opt/ibm/ILOG/CPLEX_Studio_Community201/cplex/include;/opt/ibm/ILOG/CPLEX_Studio_Community201/concert/include;/opt/ibm/ILOG/CPLEX_Studio_Community201/cplex/include/ilcplex;/opt/ibm/ILOG/CPLEX_Studio_Community201/concert/include/ilconcert
-- concert=
-- cplex=

CPLEX 相关的 CMake 输出是

/usr/bin/ld: cannot find -lconcert
/usr/bin/ld: cannot find -lilocplex
/usr/bin/ld: cannot find -lcplex

错误是

CMakeLists.txt

没有/usr/bin/ld: CMakeFiles/myprog.dir/src/main.cpp.o: in function `main': /<my path>/src/main.cpp:7: undefined reference to `IloCplex::IloCplex(IloModel)' 中的最后一行，错误是

IloEnv

即链接器在 /opt/ibm/ILOG/CPLEX_Studio_Community201/concert/include/ilconcert/iloenv.h 中找到类 IloModel，在 /opt/ibm/ILOG/CPLEX_Studio_Community201/concert/include/ilconcert/ilomodel.h 中找到 IloCplex，但在 /opt/ibm/ILOG/CPLEX_Studio_Community201/cplex/include/ilcplex/ilocplexi.h 中找不到 $ for f in src/*.cpp; do ... g++ -c -I/opt/ibm/ILOG/CPLEX_Studio_Community201/cplex/include ... -I/opt/ibm/ILOG/CPLEX_Studio_Community201/concert/include ... -Iinclude $f -o build/$(basename $f .cpp).o; ... done $ unset OBJ_FILES $ for i in build/*.o; do OBJ_FILES="$i $OBJ_FILES"; done $ g++ -I/opt/ibm/ILOG/CPLEX_Studio_Community201/cplex/include ... -I/opt/ibm/ILOG/CPLEX_Studio_Community201/concert/include ... -Iinclude ... -L/opt/ibm/ILOG/CPLEX_Studio_Community201/cplex/lib/x86-64_linux/static_pic ... -L/opt/ibm/ILOG/CPLEX_Studio_Community201/concert/lib/x86-64_linux/static_pic ... $OBJ_FILES ... -o progr ... -lconcert -lilocplex -lcplex -lpthread -ldl 。

从命令行编译工作（为了便于阅读，这里格式化）：

Program Explanation

1. Take the number which you have to reverse as the input and store it in the variable num.
2. Copy the input number to the another variable temp.
3. Firstly initialize the variable reverse to zero.
4. Obtain the remainder of the input number.
5. Multiply the variable reverse with 10 and add the Obtained remainder to it and store the result in the same variable.
6. Obtain the quotient of the input number and considering this as input number repeat the steps as mentioned above until the obtained quotient becomes zero.
7. When it becomes zero,using if,else statement check whether the reversed number is equal to original number or not.
8. If it is equal,then print the output as “Yes”,otherwise print the output as “No”.


    #include <stdio.h>
    void main()
    {
       int num,temp,remainder,reverse = 0;
        printf("Enter an integer \n");
        scanf("%d",&num);
        /* original number is stored at temp */
        temp = num;
        while (num > 0)
        {
            remainder = num % 10;
            reverse = reverse * 10 + remainder;
            num /= 10;
        }
        printf("Given number is = %d\n",temp);
        printf("Its reverse is  = %d\n",reverse);
        if (temp == reverse)
            printf("Yes \n");
        else
            printf("No \n");
    }
    
    Case:1
    Enter an integer
    6789
    Given number is = 6789
    Its reverse is  = 9876
    No
     
    Case:2
    Enter an integer
    58085
    Given number is = 58085
    Its reverse is  = 58085
    Yes

解决方法

正如 Tsyvarev 指出的那样：不应使用未设置的 CPLEX_ILOCPLEX_LIBRARY，而应在 CPLEX_ILO_LIBRARY 的定义中使用变量 CPLEX_LIBRARIES。