[llvm] [LangRef] Try to formalize the definition of "odr" in LLVM IR. (PR #92619)

[via llvm-commits]

https://github.com/DianQK approved this pull request.

LGTM. Thanks! For me, the explanation of the ODR variable has become much clearer.

https://github.com/llvm/llvm-project/pull/92619