Perhaps I was being too sensational in my response too. But to elaborate. I doubt there is a single distribution keeping separate repositories for every processor. Even piCore, where we have an armv6, armv7, armv7l the code in those repositories is not natively compiled. Also in piCore's case gcc is built on an armv7l processor gcc is configured by the maintainer to produce code compiled for armv6, and for the most part will do that for the casual user who builds code like
gcc -o foo foo.c
It is true that Clang/LLVM is much more restrictive in the code that it produces by default. But it has been that way, and you should always specify the desired target. If you download some source for a programs distribution, almost all of them use some sort of configure system (autoconf/libtool, meson, etc) The job of the configure system is to determine the host compiler and the target. Which then tells gcc/clang specifically what to do.