Cython扩展类：__dealloc__方法后的“释放对象的校验和不正确”

Question

好吧，我在使用Cython的C ++支持后遇到一个奇怪的错误，因为我认为manual advises（使用__cinit__分配堆RAM而__dealloc__再次释放它。< / p>

我有一个C ++类，calloc和malloc在构造函数中有一些RAM，而free在析构函数中。如果有必要，我会发布这个，但错误不是来自C ++的土地，new和delete调用工作正常，所以我现在只给你cython：

cdef extern from "../clibs/adjacency.hpp":

  cdef cppclass Adjacency:
    int* _bv
    void** _meta
    unsigned int length
    Adjacency(int graph_order, int meta_on)
    int get(int i, int j)
    void set(int i, int j, int on, void* meta)
    void reset_to_zero()
    void edges_iter(void* global_meta, void (*callback)(void*, int, int, void*))

cdef class Graph:
  cdef Adjacency* adj

  def __init__(self, graph_order):
    print "__init__"

  def __cinit__(self, graph_order, *args, **kwargs):
    print "__cinit__"
    print "allocating, no meta."
    self.adj = new Adjacency(<int>graph_order, 0)

  def __dealloc__(self):
    print "__dealloc__"
    del self.adj

当我测试时，我得到以下内容：

In [1]: import graph

In [2]: g = graph.Graph(302)
__cinit__
allocating, no meta.
__init__

In [3]: ^D
Do you really want to exit ([y]/n)? 
__dealloc__
Python(7389,0x7fff70f9acc0) malloc: *** error for object 0x100defa08: incorrect
checksum for freed object - object was probably modified after being freed.
*** set a breakpoint in malloc_error_break to debug
Abort trap

我有时也会得到段错误，而不是错误的校验和。

我破解了cython生成的C ++文件并在delete调用周围添加了以下内容：

/* "graph.pyx":75
 *   def __dealloc__(self):
 *     print "__dealloc__"
 *     del self.adj             # <<<<<<<<<<<<<<
 * 
 *   def __init__(self, graph_order):
 */
printf("about to delete adj:\n");
delete __pyx_v_self->adj;
printf("just deleted adj!\n");

我们可以清楚地看到我对delete的调用运行良好：

In [1]: import graph

In [2]: g = graph.Graph(302)
__cinit__
allocating, no meta.
__init__

In [3]: ^D
Do you really want to exit ([y]/n)? 
__dealloc__
about to delete adj:
just deleted adj!
Python(7389,0x7fff70f9acc0) malloc: *** error for object 0x100defa08: incorrect
checksum for freed object - object was probably modified after being freed.
*** set a breakpoint in malloc_error_break to debug
Abort trap

在我完成整理之后，我在Cython手册中告诉我，那个Python在之后引发了一个发脾气。

我也尝试在self.adj = NULL中设置__dealloc__，以防Python试图查看我的对象内部，但这没有帮助。

任何想法我做错了什么？

Answer 1

我在我的C ++代码中犯了一个错误（我没有展示）。

我有很多这样的功能：

if (_meta != NULL) {
  // do stuff with _meta, like loop over the void*s
}

但是在构造函数中，我在设置_meta = NULL; ...

之前调用其中一个