[clang] [clang-tools-extra] [libcxx] [clang] Enable sized deallocation by default in C++14 onwards (PR #83774)

[Chuanqi Xu via cfe-commits]

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@@ -72,6 +72,10 @@ sections with improvements to Clang's support for those languages.
 C++ Language Changes
 --------------------
 
+C++14 Feature Support
+^^^^^^^^^^^^^^^^^^^^^
+- Sized deallocation is enabled by default in C++14 onwards.
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ChuanqiXu9 wrote:

It may be good to mention the flag enabled so that people met regression can disable it locally to workaround it.

https://github.com/llvm/llvm-project/pull/83774