[clang] [clang][bytecode] Assert on virtual func call from array elem (PR #158502)

[Timm Baeder via cfe-commits]

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@@ -1100,3 +1100,25 @@ namespace DiscardedTrivialCXXConstructExpr {
   constexpr int y = foo(12); // both-error {{must be initialized by a constant expression}} \
                              // both-note {{in call to}}
 }
+
+namespace VirtualFunctionCallThroughArrayElem {
+  struct X {
+    constexpr virtual int foo() const {
+      return 3;
+    }
+  };
+  constexpr X xs[5];
+  static_assert(xs[3].foo() == 3);
+
+  constexpr X xs2[1][2];
+  static_assert(xs2[0].foo() == 3); // both-error {{is not a structure or union}}
+  static_assert(xs2[0][0].foo() == 3);
+
+  struct Y: public X {
+    constexpr int foo() const override {
+      return 1;
+    }
+  };
+  constexpr Y ys[20];
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tbaederr wrote:

can you include the original reproducer from #152893 as well? This patch fixes the assertion failure but the diagnostic output is still different between the two interpreters.

https://github.com/llvm/llvm-project/pull/158502