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

[Yeoul Na via cfe-commits]

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@@ -330,6 +330,14 @@ def warn_alias_with_section : Warning<
   "as the %select{aliasee|resolver}2">,
   InGroup<IgnoredAttributes>;
 
+let CategoryName = "Bounds Safety Issue" in {
+def err_bounds_safety_lang_not_supported : Error<
+  "bounds safety is only supported for C">;
+def warn_bounds_safety_asm_ignored : Warning<
+  "'-fbounds-safety' is ignored for assembly">,
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rapidsna wrote:

@MaskRay I removed the frontend warning, so that it follows how the driver handles unused flags. Now only `warning: argument unused during compilation` fires for `-x assembler`, and not for `-x assembler-with-cpp` to conform to most of other options.

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