https://github.com/rust-lang/rust/blob/1ca100d0428985f916eea153886762bed3909771/src/libstd/rt.rs#L31-L67 https://github.com/rust-lang/rust/blob/1ca100d0428985f9

https://github.com/rust-lang/rust/blob/1ca100d0428985f916eea153886762bed3909771/src/libstd/rt.rs#L31-L67 https://github.com/rust-lang/rust/blob/1ca100d0428985f916eea... is the "runtime". sys::thread contains all the TLS stuff (C has TLS too, so it's unclear if this is any more of a runtime). catch_unwind is for toplevel panic handling (which can be nop'd with panic=abort). Finally, we link to jemalloc, which is an additional bit of runtime of its own (which can be turned off with alloc_system)