Re: new and delete from different threads

Howard Hinnant <>
Tue, 09 May 2006 14:33:13 GMT
In article <>,
 "Dilip" <> wrote:

I am aware that the C++ standard in its present form does not say
anything about threads, however I do have a relevant question.

I am working on Windows XP/VC++ 8.0.

Is there a problem new'ing a bunch of objects from one thread and
deleting them in another? I do something like:

struct GenericPointerDeleter
    template<typename T>
    void operator()(T* p)
        if (ptr != 0)
            delete ptr;
            ptr = 0;

typedef vector<classofpointers*> vecptrs;
int main()
    vecptrs myptrs;
    CreateThread(...... (LPVOID)&myptrs........);
    // use some platform specific API to wait until
threadcallbackroutine terminates

    for_each(myptrs.begin(), myptrs.end(), GenericPointerDeleter());

DWORD WINAPI threadcallbackroutine(LPVOID param)
    vecptrs* my_ptrs = static_cast<vecptrs*>(param);
    my_ptrs->push_back(new classofpointers());
    return 0;

I have vastly simplified what is essentially happening in my

Should I be careful about new'ing and deleting from the same thread?

I don't have access to Windows, but I believe your code is fine. The
C++ committee is interested in C++0X have a multi-threaded memory model
which will probably be based on current practice today. And as far as I
know, current practice is that transferring memory ownership across
thread boundaries is fine.


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