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

[Yeoul Na via cfe-commits]

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@@ -3618,6 +3618,27 @@ void CompilerInvocationBase::GenerateLangArgs(const LangOptions &Opts,
     GenerateArg(Consumer, OPT_frandomize_layout_seed_EQ, Opts.RandstructSeed);
 }
 
+static void CheckBoundsSafetyLang(InputKind IK, DiagnosticsEngine &Diags) {
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rapidsna wrote:

> I think it's better to handle this language check in Driver, similar to OPT_fminimize_whitespace but for all Inputs.

@MaskRay If we do it in Driver, wouldn't the option be silently ignored for unsupported languages when we invoke `clang -cc1` directly?

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