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Do you really need the extern "C" declarations in the headers? This code will only be used by C++ files. Yes, I need it. If not, it makes linking errors.

I realize that this is because ewk_tiled_backing_store declare extern "C". I removed.

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And I dislike using typeof here, as it will really break the build for anything that is not gcc or clang. I suggest getting rid of the macros (you could even turn them into proper template functions) or passing another parameter to them specifying the data type.

I agree, I'll remove those macro. I thought that I'll prepare next bug for this bug to be focused renaming.

Update like you mentioned. please see attached file.

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Or, taking another step back, is this all really needed? We are have to make so many adjustments to make code which is clearly C code into an uglified C++ version, and IIRC the reason given for that was some kind of #include problem. Couldn't we fix that instead of spending so much effort into this?

Previous bug is for #include problem. so that I didn't touch other c files. But now, we are in phase to improve WebKit/efl code quality.

Because we need to change our tiled backing store until we decide whether we use WebCore version, We need reviewer's help and these cleanup will help them review easily.