.cpp linking problems

This is a discussion on .cpp linking problems within the C++ Programming forums, part of the General Programming Boards category; each time when i define a header file in my main cpp and then use the classes i define in ...

  1. #1
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    .cpp linking problems

    each time when i define a header file in my main cpp and then use the classes i define in the header file in some different cpp file it gives me "undefine" error

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    Are you compiling on the command line or in an IDE?

    --
    Mats
    Compilers can produce warnings - make the compiler programmers happy: Use them!
    Please don't PM me for help - and no, I don't do help over instant messengers.

  3. #3
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    Quote Originally Posted by matsp View Post
    Are you compiling on the command line or in an IDE?

    --
    Mats
    command line in Microsoft compiler

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    Then I will guess that you are doing something like this:
    Code:
    cl -o myprog main.cpp
    where you should do:
    Code:
    cl -o myprog main.cpp class.cpp
    (Alternatives do exist).

    Edit: What I'm trying to say is that you need to tell the compiler which CPP files it should compile (and link). Just because you include a header file doesn't automatically mean that the source file with the implementation will be compiled/linked against.

    --
    Mats
    Compilers can produce warnings - make the compiler programmers happy: Use them!
    Please don't PM me for help - and no, I don't do help over instant messengers.

  5. #5
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    Quote Originally Posted by matsp View Post
    Then I will guess that you are doing something like this:
    Code:
    cl -o myprog main.cpp
    where you should do:
    Code:
    cl -o myprog main.cpp class.cpp
    (Alternatives do exist).

    Edit: What I'm trying to say is that you need to tell the compiler which CPP files it should compile (and link). Just because you include a header file doesn't automatically mean that the source file with the implementation will be compiled/linked against.

    --
    Mats
    thanks for telling

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