"C++中使用MinGW嵌入Python3.6链接失败"

Question

在Wi1064位系统中，在C++中嵌入Python 3.6。 Python由python-3.6.1-amd64.exe安装。 这个CMakeList.txt文件显示在下面

cmake_minimum_required(VERSION 3.8)
project(EmbedPython)

set(CMAKE_CXX_STANDARD 11)

set(SOURCE_FILES main.cpp)
find_package(PythonLibs REQUIRED)
include_directories(${PYTHON_INCLUDE_DIRS})
add_executable(EmbedPython ${SOURCE_FILES} ${PYTHON_INCLUDE_DIRS})
target_link_libraries(EmbedPython ${PYTHON_LIBRARIES})

CMake找到了Python包。在

^{pr2}$

Find a comment on github它在讨论API问题。在

# used to embed python script
find_package(PythonLibs 2.7 REQUIRED) # this has to be 2.7 because the 3.0 API requires argv to be wchar_t** rather than the default char**
include_directories(${PYTHON_INCLUDE_DIRS})
target_link_libraries( assignment ${PYTHON_LIBRARIES})

下面的错误就是我所面临的。在

[ 50%] Building CXX object CMakeFiles/EmbedPython.dir/main.cpp.obj
[100%] Linking CXX executable EmbedPython.exe
CMakeFiles\EmbedPython.dir/objects.a(main.cpp.obj): In function `main':
D:/Projects/EmbedPython/main.cpp:16: undefined reference to `_imp__Py_Initialize'
D:/Projects/EmbedPython/main.cpp:17: undefined reference to `_imp__PyUnicode_DecodeFSDefault'
D:/Projects/EmbedPython/main.cpp:20: undefined reference to `_imp__PyImport_Import'
D:/Projects/EmbedPython/main.cpp:24: undefined reference to `_imp__PyObject_GetAttrString'
D:/Projects/EmbedPython/main.cpp:27: undefined reference to `_imp__PyCallable_Check'
D:/Projects/EmbedPython/main.cpp:28: undefined reference to `_imp__PyTuple_New'
D:/Projects/EmbedPython/main.cpp:30: undefined reference to `_imp__PyLong_FromLong'
D:/Projects/EmbedPython/main.cpp:38: undefined reference to `_imp__PyTuple_SetItem'
D:/Projects/EmbedPython/main.cpp:40: undefined reference to `_imp__PyObject_CallObject'
D:/Projects/EmbedPython/main.cpp:43: undefined reference to `_imp__PyLong_AsLong'
D:/Projects/EmbedPython/main.cpp:49: undefined reference to `_imp__PyErr_Print'
D:/Projects/EmbedPython/main.cpp:55: undefined reference to `_imp__PyErr_Occurred'
D:/Projects/EmbedPython/main.cpp:56: undefined reference to `_imp__PyErr_Print'
D:/Projects/EmbedPython/main.cpp:63: undefined reference to `_imp__PyErr_Print'
D:/Projects/EmbedPython/main.cpp:67: undefined reference to `_imp__Py_FinalizeEx'
collect2.exe: error: ld returned 1 exit status
mingw32-make.exe[3]: *** [EmbedPython.exe] Error 1
mingw32-make.exe[2]: *** [CMakeFiles/EmbedPython.dir/all] Error 2
mingw32-make.exe[1]: *** [CMakeFiles/EmbedPython.dir/rule] Error 2
mingw32-make.exe: *** [EmbedPython] Error 2
CMakeFiles\EmbedPython.dir\build.make:96: recipe for target 'EmbedPython.exe' failed
CMakeFiles\Makefile2:66: recipe for target 'CMakeFiles/EmbedPython.dir/all' failed
CMakeFiles\Makefile2:78: recipe for target 'CMakeFiles/EmbedPython.dir/rule' failed
Makefile:117: recipe for target 'EmbedPython' failed

不知道该怎么做才能完成这个项目跑吧。任何人如有帮助，不胜感激。在

编辑： 来自make VERBOSE=1的结果

D:\Projects\EmbedPython\cmake-build-debug>make VERBOSE=1
"C:\Program Files\JetBrains\CLion 172.2273.4\bin\cmake\bin\cmake.exe" -HD:\Projects\EmbedPython -BD:\Projects\EmbedPython\cmake-build-debug --check-build-system CMakeFiles\Makefile.cmake 0
"C:\Program Files\JetBrains\CLion 172.2273.4\bin\cmake\bin\cmake.exe" -E cmake_progress_start D:\Projects\EmbedPython\cmake-build-debug\CMakeFiles D:\Projects\EmbedPython\cmake-build-debug\CMakeFiles\progress.marks
make -f CMakeFiles\Makefile2 all
make[1]: Entering directory 'D:/Projects/EmbedPython/cmake-build-debug'
make -f CMakeFiles\EmbedPython.dir\build.make CMakeFiles/EmbedPython.dir/depend
make[2]: Entering directory 'D:/Projects/EmbedPython/cmake-build-debug'
"C:\Program Files\JetBrains\CLion 172.2273.4\bin\cmake\bin\cmake.exe" -E cmake_depends "MinGW Makefiles" D:\Projects\EmbedPython D:\Projects\EmbedPython D:\Projects\EmbedPython\cmake-build-debug D:\Projects\EmbedPython\cmake-build-debug D:\Projects\EmbedPython\cmake-build-debug\CMakeFiles\EmbedPython.dir\DependInfo.cmake --color=
make[2]: Leaving directory 'D:/Projects/EmbedPython/cmake-build-debug'
make -f CMakeFiles\EmbedPython.dir\build.make CMakeFiles/EmbedPython.dir/build
make[2]: Entering directory 'D:/Projects/EmbedPython/cmake-build-debug'
[ 50%] Linking CXX executable EmbedPython.exe
"C:\Program Files\JetBrains\CLion 172.2273.4\bin\cmake\bin\cmake.exe" -E cmake_link_script CMakeFiles\EmbedPython.dir\link.txt --verbose=1
"C:\Program Files\JetBrains\CLion 172.2273.4\bin\cmake\bin\cmake.exe" -E remove -f CMakeFiles\EmbedPython.dir/objects.a
C:\PROGRA~2\MINGW-~1\I686-6~1.0-P\mingw32\bin\ar.exe cr CMakeFiles\EmbedPython.dir/objects.a @CMakeFiles\EmbedPython.dir\objects1.rsp
C:\PROGRA~2\MINGW-~1\I686-6~1.0-P\mingw32\bin\G__~1.EXE -g   -Wl,--whole-archive CMakeFiles\EmbedPython.dir/objects.a -Wl,--no-whole-archive  -o EmbedPython.exe -Wl,--out-implib,libEmbedPython.dll.a -Wl,--major-image-version,0,--minor-image-version,0 @CMakeFiles\EmbedPython.dir\linklibs.rsp
CMakeFiles\EmbedPython.dir/objects.a(main.cpp.obj): In function `main':
D:/Projects/EmbedPython/main.cpp:16: undefined reference to `_imp__Py_Initialize'
D:/Projects/EmbedPython/main.cpp:17: undefined reference to `_imp__PyUnicode_DecodeFSDefault'
D:/Projects/EmbedPython/main.cpp:20: undefined reference to `_imp__PyImport_Import'
D:/Projects/EmbedPython/main.cpp:24: undefined reference to `_imp__PyObject_GetAttrString'
D:/Projects/EmbedPython/main.cpp:27: undefined reference to `_imp__PyCallable_Check'
D:/Projects/EmbedPython/main.cpp:28: undefined reference to `_imp__PyTuple_New'
D:/Projects/EmbedPython/main.cpp:30: undefined reference to `_imp__PyLong_FromLong'
D:/Projects/EmbedPython/main.cpp:38: undefined reference to `_imp__PyTuple_SetItem'
D:/Projects/EmbedPython/main.cpp:40: undefined reference to `_imp__PyObject_CallObject'
D:/Projects/EmbedPython/main.cpp:43: undefined reference to `_imp__PyLong_AsLong'
D:/Projects/EmbedPython/main.cpp:49: undefined reference to `_imp__PyErr_Print'
D:/Projects/EmbedPython/main.cpp:55: undefined reference to `_imp__PyErr_Occurred'
D:/Projects/EmbedPython/main.cpp:56: undefined reference to `_imp__PyErr_Print'
D:/Projects/EmbedPython/main.cpp:63: undefined reference to `_imp__PyErr_Print'
D:/Projects/EmbedPython/main.cpp:67: undefined reference to `_imp__Py_FinalizeEx'
collect2.exe: error: ld returned 1 exit status
CMakeFiles\EmbedPython.dir\build.make:97: recipe for target 'EmbedPython.exe' failed
make[2]: *** [EmbedPython.exe] Error 1
make[2]: Leaving directory 'D:/Projects/EmbedPython/cmake-build-debug'
CMakeFiles\Makefile2:66: recipe for target 'CMakeFiles/EmbedPython.dir/all' failed
make[1]: *** [CMakeFiles/EmbedPython.dir/all] Error 2
make[1]: Leaving directory 'D:/Projects/EmbedPython/cmake-build-debug'
Makefile:82: recipe for target 'all' failed
make: *** [all] Error 2

Answer 1

我也有同样的问题。在

问题可能是因为使用了32位MinGW和64位Python。您应该安装32位版本的python

希望对你有用：-）

Answer 2

我也遇到了同样的问题，只是在使用python3.7时，试图从Python手册构建example。在

我的系统是64位的Windows，安装的Python是64位的3.7（来自Anaconda3），编译器是32位的mingw5.3.0（来自qt5.11）。在

对我来说最简单的解决方案是：

• 从this页面下载Windows x86 embeddable zip file。在
• 将该存档的内容放入正在构建的项目中的文件夹中。在
• 不要安装该归档文件中的任何内容，并将其放在系统路径上。在
• 将上面的文件夹添加到gcc库搜索路径中，使用：-L"path/to/folder/"
• 使用-l"python37"（将37替换为下载的任何版本）将python库添加到链接器中
• 如前所述here（这是一个很难找到的！），添加一个定义，使用-DPy_BUILD_CORE_BUILTIN=1（也可以在#include之前写入#define DPy_BUILD_CORE_BUILTIN 1-尽管我不建议这样做）
• 使用-I"path/to/include"提供Python头的路径。我用的是水蟒的，例如-I"c:/Users/user/Anaconda3/include/"。任何已安装的标头都可以，只需确保其来自同一版本（也可以使用旧版本的标头，但这可能会导致时空连续体的破裂）
• 确保#include <Python.h>位于任何其他include之前，如手册中所述。在

顺便说一句，MinGW链接器（ld）多年来一直都很满足，如果你只给它一个“dll”文件的话。如果没有“lib”，只执行动态链接，则不需要“lib”或“a”。这就是为什么我告诉链接器使用python37。在

它实际上是smart enough来查找python37.lib，python37.dll&；libpython37.a之类的文件。在

还要注意，“embeddeble zip”只是嵌入Python所需的最低限度。在

最后一点，与here相反，从GCC链接到使用MSVS编译的库（反之亦然），只要库使用普通的C接口，因为对于任何给定的平台，这个接口几乎是所有不同编译器之间唯一兼容的东西。在

这正是Python使用“强> C++ <强>接口（而没有其他，甚至没有<强> C++<强> >）的确切原因，用于扩展和嵌入-允许使用任何工具集编写的代码与Python接口。在