catching push_back exception

From:

gene howell

Newsgroups:

microsoft.public.vc.stl

Date:

Thu, 31 Dec 2009 08:24:27 -0800

Message-ID:

<20091231112422ehowell@arinc.com>

I tried your suggestion with the simple program above and it did not work. That is, I had:

for(theint=0; theint < 20000000000; theint++)
{
    try
    {
        thevector.push_back(theint);
    }
    catch ( const std::bad_alloc & e )
    {
        return 0;
    }
    catch ( const std::exception & e )
    {
        return 0;
    }
}

The program crashed (threw an exception) on the push_back(*) call. Am I missing something simple? Any idea why the exception would not be handled? BTW, the value of theint when it crashed was 67108864. Thanks.

Gene

Arnie wrote:

Exactly.
02-Apr-08

Exactly. Use something like:
try
{
// your code
}
catch ( const std:bad_alloc & e )
{
// Handle out of memory
}
catch ( const std:exception & e )
{
// Something else 'bad' happened
}

- Arnie

Previous Posts In This Thread:

On Wednesday, April 02, 2008 12:09 AM
kevi wrote:

push_back causes crash at the limits of memory
My program crashes on executing a push_back, triggering the message:

This application has requested the Runtime to terminate it in an unusual way.
Please contact the application's support team for more information.

I am running the program on a 32bit Windows XP Pro machine. At the time I
start my loop with the push_back, the program has already used up 1.5GB of
memory. Somewhere in the middle of my loop, the push_back crashes the
program with the above message. In this case, the user has data which
exceeds the addressable memory, but the push_back does not die gracefully.
Is there some way to stop it from crashing when it can not allocate memory on
a push_back?

For example, this program dies in a similar manner:

using namespace std;

int main()
{
  vector<long long> thevector;
  longlong theint;

  for(theint=0; theint < 20000000000; theint++)
  {
    thevector.push_back(theint);
  }

  return 0;
}

On Wednesday, April 02, 2008 12:32 AM
Doug Harrison [MVP] wrote:

Re: push_back causes crash at the limits of memory
wrote:

Try catching the exception that push_back throws.

--
Doug Harrison
Visual C++ MVP

On Wednesday, April 02, 2008 12:33 AM
Igor Tandetnik wrote:

Re: push_back causes crash at the limits of memory
"kevin" <kevin@discussions.microsoft.com> wrote in message
news:7B005564-D7DC-495B-A5DD-E458488A4417@microsoft.com

It doesn't crash. push_back throws a bad_alloc exception, which your
program doesn't catch. An uncaught exception causes the runtime to
terminate the program.
--
With best wishes,
    Igor Tandetnik

With sufficient thrust, pigs fly just fine. However, this is not
necessarily a good idea. It is hard to be sure where they are going to
land, and it could be dangerous sitting under them as they fly
overhead. -- RFC 1925

On Wednesday, April 02, 2008 9:04 AM
Arnie wrote:

Exactly.
Exactly. Use something like:
try
{
// your code
}
catch ( const std:bad_alloc & e )
{
// Handle out of memory
}
catch ( const std:exception & e )
{
// Something else 'bad' happened
}

- Arnie

On Monday, April 07, 2008 12:16 PM
Green wrote:

Hi,vector only support 67108864 elements,over the number will crash ,and
Hi,
vector only support 67108864 elements,
over the number will crash ,and push_back not throw exceptions.

yours,
Tylor

On Monday, April 07, 2008 12:27 PM
Green wrote:

Re: push_back causes crash at the limits of memory
Hi,

?
vector::max_size ?

yours,
Tylor

On Monday, April 07, 2008 12:30 PM
Doug Harrison [MVP] wrote:

Re: push_back causes crash at the limits of memory
If true, I suspect it depends heavily on virtual memory settings, and in
any case, it would be a bug.

--
Doug Harrison
Visual C++ MVP

On Monday, April 07, 2008 1:06 PM
Alex Blekhman wrote:

Re: push_back causes crash at the limits of memory
"Doug Harrison [MVP]" wrote:

I think that OP refers to `vector::max_size()' method. The return
value of the `vector::max_size()' method depends on the size of
the type that was used to instatiate its allocator. MS's
implementation returns "(size_t)(-1) / sizeof (_Ty)" value, where
_Ty is the actual type of a vector (and its allocator).

The single restriction that the standard imposes on this value is
that it is "the largest value that can meaningfully be passed to
X::allocate().". Of course, it's nowhere near the true allocation
limit for the vector.

Alex

On Monday, April 07, 2008 3:32 PM
Doug Harrison [MVP] wrote:

Re: push_back causes crash at the limits of memory
On Mon, 7 Apr 2008 20:06:08 +0300, "Alex Blekhman" <tkfx.REMOVE@yahoo.com>
wrote:

If that's what he was thinking, I don't know how he came up with 67,108,864
elements for a vector of 8-byte integers (long long).

Right, the actual limit is usually a lot less.

--
Doug Harrison
Visual C++ MVP

On Tuesday, April 08, 2008 11:28 AM
Alex Blekhman wrote:

Re: push_back causes crash at the limits of memory
"Doug Harrison [MVP]" wrote:

It seems that OP measured it once for some type with sizeof = 16
and then remembered it.

Alex

Submitted via EggHeadCafe - Software Developer Portal of Choice
Use the Google Reader API to purge old feeds
http://www.eggheadcafe.com/tutorials/aspnet/02188aa0-d50b-42fe-9bdb-30a321dd7671/use-the-google-reader-api.aspx