Naa, it looks like it's failing to include the standard system include directories. If you take then from gcc and pass them as -I, it'll compile.

Can confirm (on aarch64 host)

    $ ./target/release/ccc-arm -I /usr/include/ -I /usr/local/include/ -I /usr/lib/gcc/aarch64-redhat-linux/15/include/ -o hello hello.c 

    $ ./hello
    Hello from CCC!

Seems this non-artificial intelligence model just too limited to understand concept of include path.

It’s machine specific

Hmm, I didn't have to do that. https://i.imgur.com/OAEtgvr.png

But yeah, either way it just needs to know where to find the stdlib.

Probably depends on where your distro puts stuff by default, I think it has a few of the common include paths hardcoded.

Makes sense for the behavior.