Force CMake/VisualStudio to use static libs of Boost.Python

Question

I'm currently trying to build on Windows (with Intel compiler) a big project compiling very well on UNIX with CMake. Here is a reduced simple example of my problem.

Running the following simple example of code using Boost.Python :

#include <iostream>
#include <Python.h>
#include <boost/python.hpp>

int main()
{
    std::string python_home = "C:\\softs\\python\\2.7.9\\64";
    char* python_home_char = new char[python_home.length() + 1];
    strcpy(python_home_char, python_home.c_str());
    Py_SetPythonHome(python_home_char);
    Py_Initialize();

    boost::python::object pyobj_main = boost::python::import("__main__");
    boost::python::object glob = pyobj_main.attr("__dict__");
    boost::python::exec("print \"Hello from Python\"", glob, glob);

    Py_Finalize();

    return 0;
}

I get the following error message when executing the code :

The program can't start because boost_python-iw-mt-1_57.dll is missing from your computer. Try reinstalling the program to fix this problem.

Note that I don't have the error if a remove the 3 lines boost::python::*** at the end of the code. Also, I don't have any error if I compile the following example using Boost.Thread (In my mind, it also use libraries (not header only), is it right ?) :

#include <iostream>
#include <boost/thread.hpp>

boost::mutex mutex_hello;
void hello(unsigned long int thread_number)
{
    boost::mutex::scoped_lock lock_hello(mutex_hello);
    std::cout << "Hello from thread " << thread_number << std::endl;
}

int main()
{
    boost::thread_group group;
    for(unsigned long int i = 0; i < 9; ++i)
        group.create_thread(boost::bind(hello, i + 1));
    group.join_all();

    return 0;
}

Actually, I don't want to use shared libraries, I want my executable more static as possible.

I build this code with the following CMake file :

cmake_minimum_required(VERSION 2.8.9)

# Project
project(TestBoost)
enable_language(C)
enable_language(CXX)
enable_language(Fortran)

# Compiler info
if(CMAKE_SYSTEM_NAME STREQUAL "Windows")
    set(CompilerName "${CMAKE_CXX_COMPILER_ID}")
    set(CompilerVersion "${CMAKE_CXX_COMPILER_VERSION}")
    if(CMAKE_CL_64)
        set(CompilerArch "64")
    else()
        set(CompilerArch "32")
    endif()
endif()
string(TOLOWER "${CompilerName}" CompilerName)
if("${CompilerVersion}" MATCHES "([0-9]+\\.[0-9]+\\.[0-9]+)\\..*")
    string(REGEX REPLACE "([0-9]+\\.[0-9]+\\.[0-9]+)\\..*" "\\1" CompilerVersion "${CompilerVersion}")
endif()

# Libs
set(CMAKE_FIND_LIBRARY_SUFFIXES .lib .a ${CMAKE_FIND_LIBRARY_SUFFIXES})

# Intel
if(CompilerName STREQUAL "intel")
    string(REGEX REPLACE "(.*)/bin/.*" "\\1" IntelPath "${CMAKE_C_COMPILER}")
    if(CompilerArch STREQUAL "32")
        set(IntelArchStr "ia32")
    elseif(CompilerArch STREQUAL "64")
        set(IntelArchStr "intel64")
    endif()
    set(Compiler_LIBRARY_DIRS "${IntelPath}/compiler/lib/${IntelArchStr}")
endif()

# Boost
set(BOOST_ROOT "C:/softs/boost/1.57.0/${CompilerArch}/${CompilerName}/${CompilerVersion}")
set(Boost_USE_MULTITHREAD ON)
set(Boost_USE_STATIC_LIBS ON)
set(Boost_NO_SYSTEM_PATHS ON)
set(Boost_ADDITIONAL_VERSIONS "1.57.0" "1.57")
find_package(Boost 1.57.0 REQUIRED COMPONENTS thread system filesystem python)

# Python
set(PythonPath C:/softs/python/2.7.9/${CompilerArch})
set(Python_INCLUDE_DIRS ${PythonPath}/include)
set(Python_LIBRARY_DIRS ${PythonPath}/libs)
set(Python_LIBRARIES python27)

# Executable
include_directories(SYSTEM ${Boost_INCLUDE_DIRS} ${Python_INCLUDE_DIRS})
link_directories(${Boost_LIBRARY_DIRS} ${Python_LIBRARY_DIRS} ${Compiler_LIBRARY_DIRS})
add_executable(test_boost test_boost.cpp)
target_link_libraries(test_boost ${Boost_LIBRARIES} ${Python_LIBRARIES})

I run this CMake script with an initial entry CMAKE_GENERATOR_TOOLSET set to Intel C++ Compiler XE 14.0, and specifying Intel compiler as native compiler. I have no error or warning while running CMake on it (see the log below). This generates a file TestBoost.sln. When loaded in Visual Studio Professional 2013, I change the compilation type to Release and modify the linker options of the target test_boost to add /NODEFAULTLIB:LIBCMT (workaround due to a bug in CMake). Then I compile without any error.

Log from CMake :

The C compiler identification is Intel 14.0.4.20140805
The CXX compiler identification is Intel 14.0.4.20140805
Check for working C compiler using: Visual Studio 12 2013 Win64
Check for working C compiler using: Visual Studio 12 2013 Win64 -- works
Detecting C compiler ABI info
Detecting C compiler ABI info - done
Check for working CXX compiler using: Visual Studio 12 2013 Win64
Check for working CXX compiler using: Visual Studio 12 2013 Win64 -- works
Detecting CXX compiler ABI info
Detecting CXX compiler ABI info - done
The Fortran compiler identification is Intel
Check for working Fortran compiler using: Visual Studio 12 2013 Win64
Check for working Fortran compiler using: Visual Studio 12 2013 Win64  -- works
Detecting Fortran compiler ABI info
Detecting Fortran compiler ABI info - done
Determine Intel Fortran Compiler Implicit Link Path
Determine Intel Fortran Compiler Implicit Link Path -- done
Checking whether C:/Program Files (x86)/Intel/Composer XE 2013 SP1/bin/intel64/icl.exe supports Fortran 90
Checking whether C:/Program Files (x86)/Intel/Composer XE 2013 SP1/bin/intel64/icl.exe supports Fortran 90 -- yes
[ C:/Program Files (x86)/CMake/share/cmake-3.1/Modules/FindBoost.cmake:515 ] _boost_TEST_VERSIONS = 1.57.0;1.57
[ C:/Program Files (x86)/CMake/share/cmake-3.1/Modules/FindBoost.cmake:517 ] Boost_USE_MULTITHREADED = TRUE
[ C:/Program Files (x86)/CMake/share/cmake-3.1/Modules/FindBoost.cmake:519 ] Boost_USE_STATIC_LIBS = ON
[ C:/Program Files (x86)/CMake/share/cmake-3.1/Modules/FindBoost.cmake:521 ] Boost_USE_STATIC_RUNTIME = 
[ C:/Program Files (x86)/CMake/share/cmake-3.1/Modules/FindBoost.cmake:523 ] Boost_ADDITIONAL_VERSIONS = 1.57.0;1.57
[ C:/Program Files (x86)/CMake/share/cmake-3.1/Modules/FindBoost.cmake:525 ] Boost_NO_SYSTEM_PATHS = ON
[ C:/Program Files (x86)/CMake/share/cmake-3.1/Modules/FindBoost.cmake:577 ] Declared as CMake or Environmental Variables:
[ C:/Program Files (x86)/CMake/share/cmake-3.1/Modules/FindBoost.cmake:579 ]   BOOST_ROOT = C:/softs/boost/1.57.0/64/intel/14.0.4
[ C:/Program Files (x86)/CMake/share/cmake-3.1/Modules/FindBoost.cmake:581 ]   BOOST_INCLUDEDIR = 
[ C:/Program Files (x86)/CMake/share/cmake-3.1/Modules/FindBoost.cmake:583 ]   BOOST_LIBRARYDIR = 
[ C:/Program Files (x86)/CMake/share/cmake-3.1/Modules/FindBoost.cmake:585 ] _boost_TEST_VERSIONS = 1.57.0;1.57
[ C:/Program Files (x86)/CMake/share/cmake-3.1/Modules/FindBoost.cmake:654 ] Include debugging info:
[ C:/Program Files (x86)/CMake/share/cmake-3.1/Modules/FindBoost.cmake:656 ]   _boost_INCLUDE_SEARCH_DIRS = C:/softs/boost/1.57.0/64/intel/14.0.4/include;C:/softs/boost/1.57.0/64/intel/14.0.4;NO_CMAKE_SYSTEM_PATH
[ C:/Program Files (x86)/CMake/share/cmake-3.1/Modules/FindBoost.cmake:658 ]   _boost_PATH_SUFFIXES = boost-1_57_0;boost_1_57_0;boost/boost-1_57_0;boost/boost_1_57_0;boost-1_57;boost_1_57;boost/boost-1_57;boost/boost_1_57
[ C:/Program Files (x86)/CMake/share/cmake-3.1/Modules/FindBoost.cmake:678 ] location of version.hpp: C:/softs/boost/1.57.0/64/intel/14.0.4/include/boost-1_57/boost/version.hpp
[ C:/Program Files (x86)/CMake/share/cmake-3.1/Modules/FindBoost.cmake:702 ] version.hpp reveals boost 1.57.0
[ C:/Program Files (x86)/CMake/share/cmake-3.1/Modules/FindBoost.cmake:787 ] guessed _boost_COMPILER = -iw
[ C:/Program Files (x86)/CMake/share/cmake-3.1/Modules/FindBoost.cmake:797 ] _boost_MULTITHREADED = -mt
[ C:/Program Files (x86)/CMake/share/cmake-3.1/Modules/FindBoost.cmake:840 ] _boost_RELEASE_ABI_TAG = -
[ C:/Program Files (x86)/CMake/share/cmake-3.1/Modules/FindBoost.cmake:842 ] _boost_DEBUG_ABI_TAG = -gd
[ C:/Program Files (x86)/CMake/share/cmake-3.1/Modules/FindBoost.cmake:890 ] _boost_LIBRARY_SEARCH_DIRS = C:/softs/boost/1.57.0/64/intel/14.0.4/lib;C:/softs/boost/1.57.0/64/intel/14.0.4/stage/lib;C:/softs/boost/1.57.0/64/intel/14.0.4/include/boost-1_57/lib;C:/softs/boost/1.57.0/64/intel/14.0.4/include/boost-1_57/../lib;C:/softs/boost/1.57.0/64/intel/14.0.4/include/boost-1_57/stage/lib;NO_CMAKE_SYSTEM_PATH
[ C:/Program Files (x86)/CMake/share/cmake-3.1/Modules/FindBoost.cmake:1001 ] Searching for THREAD_LIBRARY_RELEASE: libboost_thread-iw-mt-1_57;libboost_thread-iw-mt;libboost_thread-mt-1_57;libboost_thread-mt;libboost_thread;libboost_thread-iw-mt-s-1_57;libboost_thread-iw-mt-s;libboost_thread-mt-s-1_57;libboost_thread-mt-s
[ C:/Program Files (x86)/CMake/share/cmake-3.1/Modules/FindBoost.cmake:1037 ] Searching for THREAD_LIBRARY_DEBUG: libboost_thread-iw-mt-gd-1_57;libboost_thread-iw-mt-gd;libboost_thread-mt-gd-1_57;libboost_thread-mt-gd;libboost_thread-mt;libboost_thread;libboost_thread-iw-mt-s-gd-1_57;libboost_thread-iw-mt-s-gd;libboost_thread-mt-s-gd-1_57;libboost_thread-mt-s-gd
[ C:/Program Files (x86)/CMake/share/cmake-3.1/Modules/FindBoost.cmake:1001 ] Searching for SYSTEM_LIBRARY_RELEASE: libboost_system-iw-mt-1_57;libboost_system-iw-mt;libboost_system-mt-1_57;libboost_system-mt;libboost_system;libboost_system-iw-mt-s-1_57;libboost_system-iw-mt-s;libboost_system-mt-s-1_57;libboost_system-mt-s
[ C:/Program Files (x86)/CMake/share/cmake-3.1/Modules/FindBoost.cmake:1037 ] Searching for SYSTEM_LIBRARY_DEBUG: libboost_system-iw-mt-gd-1_57;libboost_system-iw-mt-gd;libboost_system-mt-gd-1_57;libboost_system-mt-gd;libboost_system-mt;libboost_system;libboost_system-iw-mt-s-gd-1_57;libboost_system-iw-mt-s-gd;libboost_system-mt-s-gd-1_57;libboost_system-mt-s-gd
[ C:/Program Files (x86)/CMake/share/cmake-3.1/Modules/FindBoost.cmake:1001 ] Searching for FILESYSTEM_LIBRARY_RELEASE: libboost_filesystem-iw-mt-1_57;libboost_filesystem-iw-mt;libboost_filesystem-mt-1_57;libboost_filesystem-mt;libboost_filesystem;libboost_filesystem-iw-mt-s-1_57;libboost_filesystem-iw-mt-s;libboost_filesystem-mt-s-1_57;libboost_filesystem-mt-s
[ C:/Program Files (x86)/CMake/share/cmake-3.1/Modules/FindBoost.cmake:1037 ] Searching for FILESYSTEM_LIBRARY_DEBUG: libboost_filesystem-iw-mt-gd-1_57;libboost_filesystem-iw-mt-gd;libboost_filesystem-mt-gd-1_57;libboost_filesystem-mt-gd;libboost_filesystem-mt;libboost_filesystem;libboost_filesystem-iw-mt-s-gd-1_57;libboost_filesystem-iw-mt-s-gd;libboost_filesystem-mt-s-gd-1_57;libboost_filesystem-mt-s-gd
[ C:/Program Files (x86)/CMake/share/cmake-3.1/Modules/FindBoost.cmake:1001 ] Searching for PYTHON_LIBRARY_RELEASE: libboost_python-iw-mt-1_57;libboost_python-iw-mt;libboost_python-mt-1_57;libboost_python-mt;libboost_python;libboost_python-iw-mt-s-1_57;libboost_python-iw-mt-s;libboost_python-mt-s-1_57;libboost_python-mt-s
[ C:/Program Files (x86)/CMake/share/cmake-3.1/Modules/FindBoost.cmake:1037 ] Searching for PYTHON_LIBRARY_DEBUG: libboost_python-iw-mt-gd-1_57;libboost_python-iw-mt-gd;libboost_python-mt-gd-1_57;libboost_python-mt-gd;libboost_python-mt;libboost_python;libboost_python-iw-mt-s-gd-1_57;libboost_python-iw-mt-s-gd;libboost_python-mt-s-gd-1_57;libboost_python-mt-s-gd
[ C:/Program Files (x86)/CMake/share/cmake-3.1/Modules/FindBoost.cmake:1088 ] Boost_FOUND = 1
Boost version: 1.57.0
Found the following Boost libraries:
  thread
  system
  filesystem
  python
Configuring done

How can I force the compilation to use only static libraries ? I thought it was the case with the options in the CMake file. Moreover, it's working with the example using threads... Maybe something is wrong in the installation of Boost.Python ?

Answer 1

When using Boost.Python, the default configuration is dynamic linking. To force static linking, define BOOST_PYTHON_STATIC_LIB in the compilation. Consider either:

• Add add_definitions(-DBOOST_PYTHON_STATIC_LIB) within CMake
• Add #define BOOST_PYTHON_STATIC_LIB before including boost/python.hpp
• Add #define BOOST_PYTHON_STATIC_LIB in boost/config/user.hpp

---

Boost.Python is an exception to the Boost_USE_STATIC_LIBS CMake variable. The FindBoost documentation notes:

On Visual Studio and Borland compilers Boost headers request automatic linking to corresponding libraries. [...] Boost automatic linking typically requests static libraries with a few exceptions (such as Boost.Python).

Unfortunately, the BOOST_PYTHON_STATIC_LIB option is neither listed in the Boost user settable options, Choosing a Boost.Python Library Binary, nor Boost.Python Configuration Information documentation.

---

A few other recommendations given your example code:

• Per Boost.Python's embedding documentation, do not invoke Py_Finalize(). Some internal Boost.Python objects will remain alive during Py_Finalize(), and only attempt to be deleted when Boost.Python unloads, causing the objects to attempt deletion with a non-existent interpreter.
• Do not directly include, python.h. If you must, consider including boost/python/detail/wrap_python.hpp instead.
• Do not include any system headers before python.h (or the Boost.Python files). This restriction is imposed by Python (see here).

The latter two recommendations documented in the #include issues section.