memory/target help

This is a discussion on memory/target help within the C++ Programming forums, part of the General Programming Boards category; I'm targeting a small linux system; but have been testing my basic functionality compiling for 16 bit dos so I ...

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    memory/target help

    I'm targeting a small linux system; but have been testing my basic functionality compiling for 16 bit dos so I can do windows type stuff at the same time I run my prog. Using um Borland 5.02.

    When I tried to use a STL 'list', I ran into th 64k text segment limit problem but changed the target type to medium which fixed it for the time being

    Unfortunately push_back crashes my program after putting about 3000 items in. I need to hold at least 30,000 preferably 120,000 elements to be safe. I'm trying to work directly with a fair sized chunk of a 300x400 image. Could this be related to my choice of targets? Would recompiling with g++ in linux be likely to help? Is there something I can do to fix it while staying in windows? Any insight would be appreciated.

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    CSharpener vart's Avatar
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    why not to use some modern 32-bit compiler? there are several free on windows?

    and why not to check the result of memory allocations instead of crashing?
    The first 90% of a project takes 90% of the time,
    the last 10% takes the other 90% of the time.

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    and the hat of int overfl Salem's Avatar
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    > I'm targeting a small linux system
    However small it is, is it really 16-bit ?

    Also, define "small"
    My phone is pretty small, but it's still a 32 bit machine with several megs of memory.

    As vart says, there are plenty of good quality and free 32 bit compilers for windows.
    If you dance barefoot on the broken glass of undefined behaviour, you've got to expect the occasional cut.
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    Small=large imbedded. yeah; is wdlinux and I guess that's probly 32 bit; and can hold lots of ram; but I dont have it here to see how much is actually in there. But neither of you indicated you think that is the source of my problem anyway, so I don't really understand why you ask.

    How do I check if push_back will work before calling it? Since I'm not personally allocating any memory and all I kinda assumed the STL code would take care of it.

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    CSharpener vart's Avatar
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    For all the container classes defined by STL, if an exception is thrown during calls to the following member functions:

    insert // single element inserted
    push_back
    push_front
    the container is left unaltered and the exception is rethrown.
    so you should catch exceptions to know if the push_back was succesful
    The first 90% of a project takes 90% of the time,
    the last 10% takes the other 90% of the time.

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    and the hat of int overfl Salem's Avatar
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    > Unfortunately push_back crashes my program after putting about 3000 items in.
    Perhaps if you post a short program which crashes, we could tell you where you're messing up.

    Maybe it's nothing at all to do with memory allocation, and it's all down to some other unrelated mistake.
    If you dance barefoot on the broken glass of undefined behaviour, you've got to expect the occasional cut.
    If at first you don't succeed, try writing your phone number on the exam paper.
    I support http://www.ukip.org/ as the first necessary step to a free Europe.

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