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Comment by viega | Hacker News Reader

If you can give me specifics on how it's not clear, I'd very much want to improve it. Please DM me about it.

Not so much that you are not clear - this is an area that is weird enough that I don't think it is possible to be clear, but you gave me some useful hints. I got some of what I want working.

Edit, I started writing and then realized that I need this to work on old gcc that doesn't support these tricks so I have to give up. (I can't wait until this old embedded hardware dies)

What I'm trying to do is #define(A, B) static int A ## _ ## B = register(MKSTRING(A ## _ ## B) take any number of arguments. I can get the register working, but my attempts are creating the variable name fail.

Thanks. Also, per another person in the thread, here are the two annotations he or she was asking for, heavily annotated.

They are both only a couple lines, but it deals with things like the fact that you've got one more argument than you should have commas, and the use of the # and ## operators in these things.

https://c.godbolt.org/z/6zqx1dsn3

Thanks. I didn't have enough levels of indirection. Once I add enough levels of indirection it works. Well works on my newer systems, I have to build for an embedded system where I'm stuck on an old compiler that doesn't support these tricks.

To be clear, the example I provided for the other person explains the bit you're missing where the names aren't working... if you carefully follow the rules, the # and ## operators don't allow expansion on their arguments, so you have to use a layer of indirection to get them expanded first.

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