[clang] [sanitizer] [clang] Introduce fsanitize-bounds-strict-flex-arrays (PR #126163)

[Vitaly Buka via cfe-commits]

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@@ -444,6 +444,19 @@ class LangOptionsBase {
     IncompleteOnly = 3,
   };
 
+  enum class ArrayBoundsStrictFlexArraysLevelKind {
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vitalybuka wrote:

We can do the same in cc1, the case will not be used, because driver will always pass something?

BTW, why -1 does not work with bitfied? I guess it will be all ones in underlying type is unsigned?

https://github.com/llvm/llvm-project/pull/126163