Is there any perf hit using DLL functions?

As the title says, compared to a normal function, is there a perf hit in calling dll functions? The dll will be loaded by dlopen. EDIT: Ignore dlsym time 开发者_StackOverflow社区because I only do it once per each function.

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Calls to DLL functions are indirect by address and the compiler can't inline them, so there is a slight performance hit.

You should only worry if you use them in a performance critical inner loop and after profiling them.

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Yes there is a performance hit. You do a dlsym call to get the function's address and then call the function with that address. As there is an added dlsym call compared to a function call from the same module, it must be slower. How much that matters? It depends. The only sure way to know is to measure it.

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The best way to find out is simply to measure...