[clang] [libcxx] [Clang] Diagnose forming references to nullptr (PR #143667)

[Corentin Jabot via cfe-commits]

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@@ -59,7 +59,7 @@ constexpr bool test() {
 
   {
     //  bidi
-    int buffer[2] = {1, 2};
+    int buffer[3] = {1, 2, 3};
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cor3ntin wrote:

It was doing an out-of-bounds read, which was not previously diagnosed 

https://github.com/llvm/llvm-project/pull/143667