[llvm] [CodeView] Read and dump LF_ALIAS (PR #218243)

[via llvm-commits]

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@@ -0,0 +1,83 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/DebugInfo/PDB/Native/NativeTypeTypedefAlias.h"
+#include "llvm/DebugInfo/PDB/Native/NativeSession.h"
+#include "llvm/DebugInfo/PDB/PDBExtras.h"
+
+using namespace llvm;
+using namespace llvm::codeview;
+using namespace llvm::pdb;
+
+NativeTypeTypedefAlias::NativeTypeTypedefAlias(NativeSession &Session,
+                                               SymIndexId Id,
+                                               TypeIndex /* TI */,
+                                               codeview::AliasRecord Typedef)
+    : NativeRawSymbol(Session, PDB_SymType::Typedef, Id),
+      Record(std::move(Typedef)) {}
+
+NativeTypeTypedefAlias::NativeTypeTypedefAlias(
+    NativeSession &Session, SymIndexId Id,
+    NativeTypeTypedefAlias &UnmodifiedType, codeview::ModifierRecord Modifier)
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Nerixyz wrote:

This isn't dead - it's used in [`SymbolCache::createSymbolForModifiedType`](https://github.com/llvm/llvm-project/pull/218243/changes#diff-f19ec5ae31612fae90dc70b82185a6cd16009972a04b30c05154ff5cccf76d18R150-R153). It's similar to how modifiers for tag records are handled.

https://github.com/llvm/llvm-project/pull/218243