时间戳

首页 > 解决方案 > 创建 pybind11 模块以返回随机火炬张量：未定义符号错误

c++ - 创建 pybind11 模块以返回随机火炬张量：未定义符号错误

问题描述

我正在尝试使用 pybind11 创建一个 python 模块来生成一个火炬张量。我在 colaboratory 做这个。wget https://download.pytorch.org/libtorch/cu102/libtorch-win-shared-with-deps-1.7.1.zip首先，我从and 获取 libtorch 库 unzip libtorch-win-shared-with-deps-1.7.1.zip。我也是git clone https://github.com/pybind/pybind11.git。

我有两个 .cpp 文件。第一个是testLibtorch.cpp，其中包含：

#include <torch/torch.h>
#include <torch/extension.h>

using torch::Tensor;

Tensor test(int num) {
  Tensor tensor1 = torch::randn({4, 3});
  return tensor1;
}

PYBIND11_MODULE(testLibtorch, m) {
    m.doc() = "hello world"; // optional module docstring
    m.def("test", &test, "A function giving torch tensor");

}

第二个是testExe.cpp，其中包含：

#include <torch/torch.h>
#include <torch/extension.h>
#include <iostream>

int main(){
  std::cout << torch::randn({4, 3}) << std::endl;
}

我正在编写自己的CMakeLists.txt：

project(torchlibtest)
cmake_minimum_required(VERSION 3.10)
set(CMAKE_CXX_STANDARD 14)

include_directories(/content/libtorch)
set(CMAKE_PREFIX_PATH "/content/libtorch/share/cmake/Torch")
find_package(Torch REQUIRED)
find_package(PythonLibs REQUIRED)
include_directories(${PYTHON_INCLUDE_DIRS})

add_subdirectory(pybind11)

pybind11_add_module(testLibtorch testLibtorch.cpp)
target_link_libraries(testLibtorch PRIVATE "${TORCH_LIBRARIES}")

target_link_libraries(testLibtorch ${MY_LIBRARIES})
set_property(TARGET testLibtorch PROPERTY CXX_STANDARD 14)

add_executable(testExe testExe.cpp)
target_link_libraries(testExe PRIVATE "${TORCH_LIBRARIES}")
if (MSVC)
  file(GLOB TORCH_DLLS "${TORCH_INSTALL_PREFIX}/lib/*.dll")
  add_custom_command(TARGET example-app
                     POST_BUILD
                     COMMAND ${CMAKE_COMMAND} -E copy_if_different
                     ${TORCH_DLLS}
                     $<TARGET_FILE_DIR:example-app>)
endif (MSVC)

然后我成功地cmake和make。但是，当我尝试导入我的模块 testLibtorch 时，我收到此错误：

---------------------------------------------------------------------------
ImportError                               Traceback (most recent call last)
<ipython-input-9-9855a0c0e93c> in <module>()
      1 import torch
----> 2 import testLibtorch
      3 print(testLibtorch.test(4))

ImportError: /content/build/testLibtorch.cpython-36m-x86_64-linux-gnu.so: undefined symbol: _Z16THPVariable_WrapN2at6TensorE

我怀疑我可能无法从 Torch 导入类和函数，但来自testExe.cpp的可执行文件似乎工作正常。将欣赏问题的解决方案，以及我正在尝试做的任务的建议和想法。

标签： c++cmakepybind11libtorch

解决方案

推荐阅读