[Pre-RFC] target-glibc: Proposal to add native support for GLIBC versions for the -gnu targets

Are there plans on making the tool that does the "local glibc -> stub library" standalone? I can forsee this being very useful even outside of Rust. Would a linker script be easier (it may well might not be, but I'm curious if it was considered)?

Also, has an equivalent for libstdc++ and/or libc++ been considered? I know Red Hat has their SCL toolchains and whatever dark arts are used to make those still work on base RHEL is also likely of interest here (at least as a learning opportunity).