[libcxx-commits] [libcxx] [libc++][hardening] Check bounds on arithmetic in __bounded_iter (PR #78876)

[Konstantin Varlamov via libcxx-commits]

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@@ -151,6 +162,10 @@ struct __bounded_iter {
   }
 
   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __bounded_iter& operator-=(difference_type __n) _NOEXCEPT {
+    _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
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var-const wrote:

Would there be any value in implementing this in terms of `operator+=`? Or would that make the call stack in case of a failed assertion too confusing?

https://github.com/llvm/llvm-project/pull/78876