Thread: including .cpp files

  1. #1
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    including .cpp files

    I'm using multiple classes that basically just interact with vectors of each other. I'm trying to test it, but I keep getting the compiler errors "undefined reference to " for my Bathroom constructor and functions.

    However, when I change the #includes from .h to the .cpp files, the program compiles and works fine. But it seems to me like it's bad practice to include .cpp files over .h files. Is this true? Or is it no big deal? I don't think I've ever included a .cpp file. I recently switched to Linux...could that be an issue somehow?

  2. #2
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    It's a bad practice.

    You need to compile/link all files together.

    g++ a.cpp b.cpp c.cpp

  3. #3
    Registered User kryptkat's Avatar
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    try extern in your .h file.

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    No need for extern if he includes the header file, as per the convention.

    There's (usually) no need to declare the same thing in different places.

  5. #5
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    s

    I tried running g++ <list of all .cpp files>, but nothing happened. Like the terminal just reset to waiting for me to put a command in. Is there a way to do this in the Code::Blocks IDE? I am used to Windows (I originally had this program on Windows working fine, now I'm trying to remake it), so I am a little new to using Linux. Is there is anything else I need to do (or could do) other than go to the terminal and do g++ .cpp files?

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    I tried running g++ <list of all .cpp files>, but nothing happened. Like the terminal just reset to waiting for me to put a command in.
    GCC only outputs something if there were errors/warnings.

    No output means everything was fine.
    Code:
    ./a.out
    to run it.

  7. #7
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    Sorry but I don't see what you mean by ./a.out. I tried "path/mainfile.cpp.out" and "g++ path/mainfile.cpp.out" and "/path/mainfile out" and other ones...what do you mean exactly?

  8. #8
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    GCC produces a binary called "a.out" by default if you don't specify the output file name.

    Try "cd"ing into the directory that has all your cpps, do
    g++ a.cpp b.cpp c.cpp...
    then
    ./a.out

  9. #9
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    Thank you so much

  10. #10
    Registered User jeffcobb's Avatar
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    Or just do:
    Code:
    g++ a.cpp b.cpp c.cpp -o myexecutable
    ./myexecutable
    C/C++ Environment: GNU CC/Emacs
    Make system: CMake
    Debuggers: Valgrind/GDB

  11. #11
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    It works in C::B too. Just add all your source files to the project. It should compile and link them all.
    Quote Originally Posted by Adak View Post
    io.h certainly IS included in some modern compilers. It is no longer part of the standard for C, but it is nevertheless, included in the very latest Pelles C versions.
    Quote Originally Posted by Salem View Post
    You mean it's included as a crutch to help ancient programmers limp along without them having to relearn too much.

    Outside of your DOS world, your header file is meaningless.

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