[clang] [clang][Interp] Implement dynamic memory allocation handling (PR #70306)

[Timm Baeder via cfe-commits]

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@@ -2771,6 +2771,109 @@ bool Compiler<Emitter>::VisitCXXInheritedCtorInitExpr(
   return this->emitCall(F, 0, E);
 }
 
+template <class Emitter>
+bool Compiler<Emitter>::VisitCXXNewExpr(const CXXNewExpr *E) {
+  assert(classifyPrim(E->getType()) == PT_Ptr);
+  const Expr *Init = E->getInitializer();
+  QualType ElementType = E->getAllocatedType();
+  std::optional<PrimType> ElemT = classify(ElementType);
+  unsigned PlacementArgs = E->getNumPlacementArgs();
+  bool IsNoThrow = false;
+
+  // FIXME: Better diagnostic. diag::note_constexpr_new_placement
+  if (PlacementArgs != 0) {
+    // The only new-placement list we support is of the form (std::nothrow).
+    //
+    // FIXME: There is no restriction on this, but it's not clear that any
+    // other form makes any sense. We get here for cases such as:
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tbaederr wrote:

Yep, I saw. I'll wait for @cor3ntin to come up with the test cases though :)

https://github.com/llvm/llvm-project/pull/70306