[clang] [Driver][BoundsSafety] Add -fbounds-safety-experimental flag (PR #70480)

[Dan Liew via cfe-commits]

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@@ -3835,6 +3852,12 @@ bool CompilerInvocation::ParseLangArgs(LangOptions &Opts, ArgList &Args,
   Opts.Trigraphs =
       Args.hasFlag(OPT_ftrigraphs, OPT_fno_trigraphs, Opts.Trigraphs);
 
+  Opts.BoundsSafety = Args.hasFlag(OPT_fbounds_safety, OPT_fno_bounds_safety,
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delcypher wrote:

I thought using `LangOpts<"BoundsSafety">` in the flag definition was supposed to automatically propagate the flag value in the frontend into the language options for you. Is that not happening?

https://github.com/llvm/llvm-project/pull/70480