He probably needs to cross-compile it. pandoc specifically has a history of not building on ARM boxes directly because it runs out of memory during the build.
And GHC support for ARM in general has been spotty. I know pandoc wouldn't build on Apple Silicon last time I tried to install it, but that was a few months ago.
That's a nice thing about C. It'll compile and run on basically anything.
I'm not gonna question it when someone says they ran into issues compiling something on a different architecture. God knows I've had enough obscure problems with it in the past.
