has extra checking, extra initialisaton and other features which makes locating problems easier, it is also not optimised to make debugging make more sense. Because of all of these settings though, the debug mode version runs at a fraction of the speed of the release mode.
mode has none of the initialisation of released mode. Where debug mode allocates memory, sets it to a value (which is never null, so it is always a good idea to initialise it yourself anyway) and then gives it to you, release mode just allocates the memory and gives it to you. Release mode also has none of the extra checking of debug mode. Finally release mode is optimised. All of these added together gives a large speed boost over debug mode.
But the only way release/debug mode could affect the include path is if a directory is given via the /I (additional include directories).
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