[clang] [llvm] [LangRef] Clarify specification for float min/max operations (PR #172012)

[Nikita Popov via cfe-commits]

nikic wrote:

@arsenm @jcranmer-intel @jyknight I think I've addressed all the actionable review comments. Can you please take another look and approve if you are happy with the proposed wording?

https://github.com/llvm/llvm-project/pull/172012