Re: Singleton_pattern and Thread Safety

From:
Leigh Johnston <leigh@i42.co.uk>
Newsgroups:
comp.lang.c++
Date:
Wed, 15 Dec 2010 00:42:43 +0000
Message-ID:
<_bOdnSmBYpRmk5XQnZ2dnUVZ7v0AAAAA@giganews.com>
On 15/12/2010 00:26, Ian Collins wrote:

On 12/15/10 01:10 PM, Leigh Johnston wrote:

On 14/12/2010 22:45, Ian Collins wrote:

On 12/15/10 11:32 AM, Leigh Johnston wrote:

You are starting to seem like a tedious troll.


Ah good, an insult. I win.


You have not won.

Microsoft agrees with me on the definition of a memory leak. Given the
following program:

char* p = new char[4242];

int main()
{
_CrtSetDbgFlag ( _CRTDBG_ALLOC_MEM_DF | _CRTDBG_LEAK_CHECK_DF );
}

The following is output on program termination:

Detected memory leaks!
Dumping objects ->
{68} normal block at 0x007C4A20, 4242 bytes long.
Data: < > CD CD CD CD CD CD CD CD CD CD CD CD CD CD CD CD
Object dump complete.


Well valgrind and dbx agree with me:

dbx:
Checking for memory leaks...

Actual leaks report (actual leaks: 0 total size: 0 bytes)

Possible leaks report (possible leaks: 0 total size: 0 bytes)

Checking for memory use...

Blocks in use report (blocks in use: 1 total size: 4242 bytes)

Total % of Num of Avg Allocation call stack
Size All Blocks Size
========== ==== ====== ====== =======================================
4242 100% 1 4242 operator new < operator new[] < __SLIP.INIT_A <
__STATIC_CONSTRUCTOR < __cplus_fini_at_exit

valgrind:

==2276== HEAP SUMMARY:
==2276== in use at exit: 4,242 bytes in 1 blocks
==2276== total heap usage: 1 allocs, 0 frees, 4,242 bytes allocated
==2276==
==2276== LEAK SUMMARY:
==2276== definitely lost: 0 bytes in 0 blocks
==2276== indirectly lost: 0 bytes in 0 blocks
==2276== possibly lost: 0 bytes in 0 blocks
==2276== still reachable: 4,242 bytes in 1 blocks
==2276== suppressed: 0 bytes in 0 blocks


valgrind is agreeing with me; it is calling it a "still reachable" leak.

Why don't you just stop digging a hole for yourself?

/Leigh

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