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Co-authored-by: Noah Lev <camelidcamel@gmail.com>

Author: tshepang

src/backend/backend-agnostic.md

@@ -8,7 +8,7 @@ namely LLVM, [Cranelift], and [GCC].
 
 [Cranelift]: https://github.com/bjorn3/rustc_codegen_cranelift
 [GCC]: https://github.com/rust-lang/rustc_codegen_gcc
-[`rustc_codegen_ssa`]: https://doc.rust-lang.org/stable/nightly-rustc/rustc_codegen_ssa/index.html
+[`rustc_codegen_ssa`]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_codegen_ssa/index.html
 
 # Refactoring of `rustc_codegen_llvm`
 by Denis Merigoux, October 23rd 2018