llvm-project

2ef7cbf7 - [clang] Add deprecation warning for `-Ofast` driver option (#98736)

[clang] Add deprecation warning for `-Ofast` driver option (#98736) This patch implements consensus on the corresponding RFC documented here: https://discourse.llvm.org/t/rfc-deprecate-ofast/78687/72 Specifically, I added a deprecation warning for `-Ofast`, that suggests to use `-O3` or `-O3` with `-ffast-math`, and a new diagnostic group for aforementioned warning. Deprecation period is going to be lengthy, so I hope this PR can be merged in time for Clang 19.