Clang/LLVM now supports small chips like the attiny10! They are even more limited than regular AVR chips and use half the registers for example, but with https://reviews.llvm.org/D131867 merged it won't (usually) generate incorrect instructions.
If you don't know, the attiny10 has 1kB program storage, 32 bytes (!) of RAM, and is about the size of a grain of rice. It has only 3-4 GPIO pins.
More information:
https://github.com/llvm/llvm-project/issues/53459