[Python-Dev] PyMem_MALLOC vs PyMem_Malloc

[Hirokazu Yamamoto]

On 2010/10/31 2:32, M.-A. Lemburg wrote:
> M.-A. Lemburg wrote:
>> Hirokazu Yamamoto wrote:
>>> Hello. I found several codes using PyMem_Free to free
>>> allocated memory with PyMem_MALLOC (ie: PyUnicode_AsWideCharString)
>>>
>>> Is it safe?
>>
>> Within the interpreter: yes.
>>
>> In extensions: depends on the platform, but probably not.
>>
>> The macros provide faster access to the C lib malloc calls.
>>
>> The functions need to be used in extensions in case the interpreter will
>> free the resource or the extension wants to free an interpreter
>> allocated resource. They provide access to the malloc calls
>> used by the interpreter, which may operate on a different heap
>> than the extensions.
>>
>> Within an extension the macros use the extension heap.
>>
>> A subtle, but important difference.
>
> BTW: If you were referring to extensions using PyMem_Free()
> to deallocate memory allocated in the interpreter using
> PyMem_MALLOC(), then that's exactly how things should be
> done.
>
> I was referring to use of the two mentioned APIs within
> an extension.

Thank you for reply, probably I could understand.