Re: [vox-tech] C++ problem

[Richard Harke <paleopenguin@gmailMAPS.com>]

Thanks for the suggestion. With valgrind I found all the problems. That the variable was local to the constructor was not a problem.

The main problem was that I was later assigning another value, over-writing the value from new. And of course that meant the

delete couldn't work either. I have a larger program that does extensive new's and deletes and I have had it run for hours without

running out of memory. I wrote that several years ago and I guess I've gotten rusty.

On Sun, May 13, 2012 at 12:04 AM, Harold Lee <harold@hotelling.net> wrote:

Using delete[] for an array allocated with new[] is correct, so I
don't think you've given us enough information to find the bug.

Are you getting any compiler warnings or errors?
Have you tried compiling with -Wall and -Wextra?
Are any of these overwritten variables pointers into the array var?
Could the array size stored at address (var - 4) have been overwritten
by accident by some other code?
Have you tried using valgrind to automatically find an accidental
overwrite earlier in execution?

Harold

On Sat, May 12, 2012 at 11:38 PM, Jeff Newmiller
<jdnewmil@dcn.davis.ca.us> wrote:
> It did make it to me, but
>
> a) I am out of town away from computers, and
>
> b) without a working example I probably would not look at it very closely
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> Richard Harke <paleopenguin@gmail.com> wrote:
>
>>My last post seems to have gotten lost so I'll try again.
>>
>>I'm working on a small C++ program. In one of the constructors I
>>create an array with
>>double * var = new double [size]   After use, before exiting the
>>constructor I return the memory with delete [] var  But after return
>>from the delete, several private class variables are written over.
>>I have checked that these variables are correct just before the delete
>>call and are modified right after. Does anyone have any idea what is
>>going on?
>>
>>I'm running debian squeeze for amd64  with gcc 4.4.5 This morning I
>>did an apt-get upgrade to be sure I had any recent fixes.
>>
>>Richard Harke
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