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

[Florian Mayer via cfe-commits]

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

i have a weak preference for flags to have a value that can represent the state that is the same as if they were not passed in. that is of course also possible in the driver, but would be a bit more complexity there.

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