Thread: Visual C++ 6 Problem

  1. 01-22-2007 #1
    samGwilliam
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    Visual C++ 6 Problem

    Yes, it's me again with another strange problem.

    After switching from the Debug to Release configuration, my build started throwing up an error (it always built under Debug) - an unresolved external symbol (a function, in this case).

    After some detective work, I whittled down the cause to an optimisation - regarding inline functions.

    The offending function was indeed an inline one, and making it out-of-line removed the problem.

    But why should this error occur in the first place? Why the trouble with inline functions?
  2. 01-22-2007 #2
    Mario F.
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    I seem to remember reading on these forums before something about inline functions, visual c++ 6.0 and a the latest patch being needed. Just in case, you have the latest patch?

    You may also avoid the error without changing your code if you change your optimization settings for inline functions. If the code is meant to be compiled on other compilers and you are sure of the advantages of keeping the function inline, this may be your best option.

    However, I don't know why you are getting this error.
    Originally Posted by brewbuck:
    Reimplementing a large system in another language to get a 25% performance boost is nonsense. It would be cheaper to just get a computer which is 25% faster.
  3. 01-22-2007 #3
    vart
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    is your inline function body located in the header?
    All problems in computer science can be solved by another level of indirection,
    except for the problem of too many layers of indirection.
    – David J. Wheeler
  4. 01-23-2007 #4
    samGwilliam
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    Quote Originally Posted by vart
    is your inline function body located in the header?
    No. Should it be?

    I thought you just followed the same conventions as an out-of-line one...
  5. 01-23-2007 #5
    swgh
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    No it shouldn't. Vart was just asking in case it was. Headers should only include function prototypes and definitions, not their implementations.
    Double Helix STL
  6. 01-23-2007 #6
    vart
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    Quote Originally Posted by swgh
    No it shouldn't. Vart was just asking in case it was. Headers should only include function prototypes and definitions, not their implementations.
    Some compilers cannot find inline functions, if the body is not present in the header file
    All problems in computer science can be solved by another level of indirection,
    except for the problem of too many layers of indirection.
    – David J. Wheeler
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