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POObjective C(++) Insanity -- simple assignement to a single float variable results in {{{CRAZY}}} values in another variable
 

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  1. POObjective C(++) Insanity -- simple assignement to a single float variable results in {{{CRAZY}}} values in another variable
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    <p>memberA is defined in the header of ClassA.</p> <p>memberB is defined in the header of ClassB.</p> <p>ClassB is a subclass of ClassA</p> <p>Inside an instance of ClassB, setting memberA via simple assignment:</p> <pre><code>memberA = 0.05 </code></pre> <p>...also changes memberB, but to a crazy number -- 1028443341. Additionally, assigning 0.05 to memberA results in memberA showing up in the debugger as 5.33083531e-38.</p> <p>Both variables are floats, neither is a pointer. I'm almost certianly making some noob mistake, but I don't have any clue what it might be. What sort of screw-up might make it so assigning a value to one variable results in crazy values appearing in two variables?</p> <p>********************* Edit **********************</p> <p>I narrowed the problem down to some "trickiness" I'd done in order to get C++ member variables:</p> <p>Thanks for all the thoughts folks. It's dangerous letting a noob like me at this low-level language stuff! Here's where the problem was:</p> <pre><code>@interface LoopyPulser : NSObject{ float _pulseRate; UInt32 tickInterval; UInt32 step; InMemoryAudioFile * audioFilePlayer; #ifdef __cplusplus ADSR* env; StkFrames* audioFrames; # endif Pattern * pattern; float loopLengthRatio; float volume; } </code></pre> <p>I read about this #ifdef __cplusplus business somewhere else on SO, as a way to have C++ imports in header files which are then imported by Obj-C files. Seems to me now that this is a terrible idea, and most likely the cause of my crazy bug. If I remove the member vars inside the #ifdef __cplusplus, the insanity goes away. </p> <p>So what's the best way to have C++ member variables in Obj-C++? Can I use ids maybe?</p>
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    1. COI'd think a set of class definitions for `A` and `B` that still reproduces the problem would be a good idea. Having a description in English as in the question fails to convey the necessary details more often than not.
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      1. USMichael Burr
    2. COAlso knowing what compiler and debugger you're using would help, it could also be that they are not working properly
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      1. USRyu
    3. COYes, I think a source code example is absolutely critical to determining a possible solution in this case.
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      1. USrcw3
 

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