Not just LLVM in itself but the Front-end codegen: AFAIK the rust front-end emits way too much LLVM IR and then counts on LLVM to optimize and they have been sl

Not just LLVM in itself but the Front-end codegen: AFAIK the rust front-end emits way too much LLVM IR and then counts on LLVM to optimize and they have been slowly adding optimizations inside the front-end itself to avoid IR bloat. And there's also the proc macro story (almost every project must compile proc_macro2 quote and syn before the actual project compilation even starts).