1 files changed, 46 insertions, 0 deletions
diff --git a/clang/lib/AST/ByteCode/Interp.h b/clang/lib/AST/ByteCode/Interp.h
index c16408c..cbd60c9 100644
--- a/clang/lib/AST/ByteCode/Interp.h
+++ b/clang/lib/AST/ByteCode/Interp.h
@@ -3290,6 +3290,52 @@ inline bool SideEffect(InterpState &S, CodePtr OpPC) {
   return S.noteSideEffect();
 }
 
+inline bool CheckBitCast(InterpState &S, CodePtr OpPC, const Type *TargetType,
+                         bool SrcIsVoidPtr) {
+  const auto &Ptr = S.Stk.peek<Pointer>();
+  if (Ptr.isZero())
+    return true;
+  if (!Ptr.isBlockPointer())
+    return true;
+
+  if (TargetType->isIntegerType())
+    return true;
+
+  if (SrcIsVoidPtr && S.getLangOpts().CPlusPlus) {
+    bool HasValidResult = !Ptr.isZero();
+
+    if (HasValidResult) {
+      if (S.getStdAllocatorCaller("allocate"))
+        return true;
+
+      const auto &E = cast<CastExpr>(S.Current->getExpr(OpPC));
+      if (S.getLangOpts().CPlusPlus26 &&
+          S.getASTContext().hasSimilarType(Ptr.getType(),
+                                           QualType(TargetType, 0)))
+        return true;
+
+      S.CCEDiag(E, diag::note_constexpr_invalid_void_star_cast)
+          << E->getSubExpr()->getType() << S.getLangOpts().CPlusPlus26
+          << Ptr.getType().getCanonicalType() << E->getType()->getPointeeType();
+    } else if (!S.getLangOpts().CPlusPlus26) {
+      const SourceInfo &E = S.Current->getSource(OpPC);
+      S.CCEDiag(E, diag::note_constexpr_invalid_cast)
+          << diag::ConstexprInvalidCastKind::CastFrom << "'void *'"
+          << S.Current->getRange(OpPC);
+    }
+  }
+
+  QualType PtrType = Ptr.getType();
+  if (PtrType->isRecordType() &&
+      PtrType->getAsRecordDecl() != TargetType->getAsRecordDecl()) {
+    S.CCEDiag(S.Current->getSource(OpPC), diag::note_constexpr_invalid_cast)
+        << diag::ConstexprInvalidCastKind::ThisConversionOrReinterpret
+        << S.getLangOpts().CPlusPlus << S.Current->getRange(OpPC);
+    return false;
+  }
+  return true;
+}
+
 /// Same here, but only for casts.
 inline bool InvalidCast(InterpState &S, CodePtr OpPC, CastKind Kind,
                         bool Fatal) {