[clang][bytecode] Check for dummy pointers when calling pseudo dtors (#137437)

Author: tbaederr

clang/lib/AST/ByteCode/Interp.cpp

@@ -1078,8 +1078,7 @@ bool CheckDummy(InterpState &S, CodePtr OpPC, const Pointer &Ptr,
   if (AK == AK_Read || AK == AK_Increment || AK == AK_Decrement)
     return diagnoseUnknownDecl(S, OpPC, D);
 
-  assert(AK == AK_Assign);
-  if (S.getLangOpts().CPlusPlus14) {
+  if (AK == AK_Destroy || S.getLangOpts().CPlusPlus14) {
     const SourceInfo &E = S.Current->getSource(OpPC);
     S.FFDiag(E, diag::note_constexpr_modify_global);
   }

clang/lib/AST/ByteCode/Interp.h

@@ -1320,6 +1320,8 @@ bool GetLocal(InterpState &S, CodePtr OpPC, uint32_t I) {
 
 static inline bool Kill(InterpState &S, CodePtr OpPC) {
   const auto &Ptr = S.Stk.pop<Pointer>();
+  if (!CheckDummy(S, OpPC, Ptr, AK_Destroy))
+    return false;
   Ptr.endLifetime();
   return true;
 }

clang/test/AST/ByteCode/lifetimes.cpp

@@ -81,4 +81,10 @@ namespace PseudoDtor {
     }
     return true;
   }
+
+  int k;
+  struct T {
+    int n : (k.~I(), 1); // both-error {{constant expression}} \
+                         // both-note {{visible outside that expression}}
+  };
 }