在 cython 中捕获 C++ 异常

Question

这两天我无法解决这个问题。 In the following code I am trying to generate uncaught exceptions in C++ code, wrap the C++ code in cython and cal the class methods in a python script. （如果重要的话，我在 Windows 上）

我设法在 python 中捕获了手动抛出的异常，但我无法捕获 c++ 代码中生成的零除错误或堆栈溢出错误，我错过了什么？

使用：Python 3.6.4 和 Cython 0.29.21

构建和启动命令： python setup.py build_ext --inplace && python main.py

异常.h

#include <stdexcept>
#include <iostream>
#include <string>

using std::cout;
// Integer division, catching divide by zero.

inline int intDivEx (int numerator, int denominator) {
    if (denominator == 0)
        throw std::overflow_error("Divide by zero exception");
    return numerator / denominator;
}
class exceptions {
    public:
        void recursion_throw(int stack) {
            cout << "\t " << stack;
//            this->recursion(stack+1);
            if (stack<1000) this->recursion(stack+1);
            else {
                throw std::overflow_error("My Stackoverflow ERROR!");
            }
        }

        double division_throw(int value) {
            int ret_value = 0;
            try { ret_value = intDivEx(1, value); }
            catch (std::overflow_error e){
                cout << e.what() << " value: ";
            }
            std::cout << value << std::endl;

            return 0;
        }

        void recursion(int stack) {
            cout << "\t " << stack;
            this->recursion(stack+1);
        }

        double division(int value) {
            int ret_value = 0;
            ret_value = 1/value;
            return ret_value;
        }

};

测试.pyx

# distutils: language = c++
import cython

from libcpp.string cimport string


cdef extern from "exceptions.h":
    cdef cppclass exceptions:
        void recursion_throw(int stack) except +
        double division_throw(int value) except +
        void recursion(int stack) except +
        double division(int value) except +


cdef class Exceptions:
    cdef exceptions excps


    def recursion(self):
        print("Running recursion")
        self.excps.recursion(0)

    def division(self, value):
        print("Running division")
        try:
            return self.excps.division(value)
        except Exception as e:
            print(e)

安装程序.py

from distutils.core import setup
from Cython.Build import cythonize


setup(ext_modules=cythonize("test.pyx"),)

主文件

#!/usr/bin/env python

import test
import traceback

if __name__ == '__main__':
    S = test.Exceptions()

    S.division(0)
    try:
        S.recursion()
    except RuntimeError as e:
        print()
        print(traceback.format_exc())

Answer 1

由于您使用的是 Windows，如果您使用的是 VS C++ 编译器，您可以设置异常处理标志以启用 SEH 异常，如下所示： /EHa

这将允许它捕获“硬”异常，例如除以零。 然后在 Python 你会看到：

...
RuntimeError: Unknown exception

这并不理想，但仍然比无声的崩溃要好。