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    <p>If you want this kind of self-registering behavior in your "modules", your assumption that the linker is optimizing out initModule because it is not directly referenced may be incorrect (though it could also be correct :-).</p> <p>When you register these modules, are you modifying another static variable defined at file scope? If so, you at least have an initialization order problem. This could even manifest itself only in release builds (initialization order can vary depending on compiler settings) which might lead you to believe that the linker is optimizing out this initModule variable even though it may not be doing so.</p> <p>The module registry kind of variable (be it a list of registrants or whatever it is) should be lazy constructed if you want to do things this way. Example:</p> <pre><code>static vector&lt;string&gt; unsafe_static; // bad vector&lt;string&gt;&amp; safe_static() { static vector&lt;string&gt; f; return f; } // ok </code></pre> <p>Note that the above has problems with concurrency. Some thread synchronization is needed for multiple threads calling safe_static.</p> <p>I suspect your real problem has to do with initialization order even though it may appear that the initModule definition is being excluded by the linker. Typically linkers don't omit references which have side effects.</p> <p>If you find out for a fact that it's not an initialization order problem and that the code is being omitted by the linker, then one way to force it is to export initModule (ex: dllexport on MSVC). You should think carefully if this kind of self-registration behavior really outweighs the simple process of adding on to a list of function calls to initialize your "modules". You could also achieve this more naturally if each "module" was defined in a separate shared library/DLL, in which case your macro could just be defining the function to export which can be added automatically by the host application. Of course that carries the burden of having to define a separate project for each "module" you create as opposed to just adding a self-registering cpp file to an existing project.</p>
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    1. COin my code the only other static variable is accessed exactly as you suggest through s_mapModuleFactory(). And I know the function declareModule is being called or not because it outputs some text to the console
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    2. COIn that case, here's a very heavy-handed way to try to force the compiler to include the module for MSVC: namespace { __declspec(dllexport) static int initModule = acquisition::CGenericModule::declareModule<acquisition::modules::CMyMod>("mod_name"); } Same idea for other compilers/platforms: export the symbol. "And I know the function declareModule is being called or not because it outputs some text[...]" This can be invoking undefined behavior if you are using cout. It is like writing this at file scope: static bool success = cout << "hello world"; /*cout may not be initialized*/
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    3. COI'm not using cout but ACE logging mechanism which, I believe, is initialized on first use
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