From: pavenis AT lanet DOT lv
To: Dennis Yelle <dennis51 AT jps DOT net>, djgpp AT delorie DOT com
Date: Sat, 5 May 2001 17:16:32 +0300
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Subject: Re: new doesn't throw an exception
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It seems that new is throwing bad_alloc but it's not catched. Attempt
to catch (std::exception &) also doesn't help. Getting exception after 
memory is exhausted is a rather tricky thing as throwing exception may 
require additional memory we don't have in this case.

I'm getting the same problem with gcc-2.95.3. When I'm changing
	'new long' to 'new long[100]'
I'm getting exception catched.

If I compile slightly modified example with gcc-3.0 development 
version (20010503) exception is catched also when I'm trying to 
allocating 4 bytes each time

Andris


On 4 May 2001, at 15:13, Dennis Yelle wrote:

> When I compile and run this program:
> ====================================
> #include <memory>
> #include <iostream>
> 
> int main()
> {
>   cout << "testing new long.\n";
>   int count = 0;
>   for(;;) {
>     long* p;
>     try {
>       //p = new(nothrow) long;
>       p = new long;
>     } catch (...) {
>       return 99;
>     }
>     if ( !p )
>       return 88;
>     count++;
>     if ( 0 == count % 200000)
>       cout << "I got " << count << " longs.\n";
>   }
>   cout << "I got " << count << " longs.\n";
> }
> ====================================
> I get a stack dump, and when I symify it, I get:
> 
> Call frame traceback EIPs:
>   0x00013454 ___djgpp_traceback_exit+48
>   0x00013536 _raise+94
>   0x000128bb _abort+27
>   0x0000d7eb ___default_terminate+11, line 0 of libgcc2.c
>   0x0000e27d _terminate__Fv+13, line 0 of exception.cc
>   0x0000e32a ___eh_alloc+30, line 0 of exception.cc
>   0x0000d72d ___builtin_new+65, line 0 of new1.cc
>   0x000015ca _main+42
>   0x00010992 ___crt1_startup+178
> 
> When new fails, it is supposed to throw an exception that
> can be caught with
>   catch(...)
> But it does not do so.
> Symify leads me to think that the problem is in new1.cc
> I am trying to find the file new1.cc
> It is NOT in DJLSR203.ZIP and it is not in GCC2953B.ZIP
> Can anyone tell me where to find the source file new1.cc ?
> 
> Also, it looks like new long usually allocates 24 bytes
> per requested long.  This seems excessive to me.
> Does anyone know why it should do this?
> 
> Dennis Yelle
> -- 
> I am a computer programmer and I am looking for a job.
> There is a link to my resume here:  
> http://table.jps.net/~vert/