[clang] [clang][bytecode] Catch placement-new into invalid destination (PR #164804)

[Shafik Yaghmour via cfe-commits]

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@@ -494,3 +494,32 @@ constexpr int modify_const_variable() {
 }
 static_assert(modify_const_variable()); // both-error {{not an integral constant expression}} \
                                         // both-note {{in call to}}
+
+constexpr int nullDest() {
+  new (nullptr) int{12}; // both-note {{construction of dereferenced null pointer}}
+  return 0;
+}
+static_assert(nullDest() == 0); // both-error {{not an integral constant expression}} \
+                                // both-note {{in call to}}
+
+constexpr int nullArrayDest() {
+  new (nullptr) int{12}; // both-note {{construction of dereferenced null pointer}}
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shafik wrote:

It looks like you intended to make this an array but did not.

https://github.com/llvm/llvm-project/pull/164804