Index: lld/COFF/Chunks.h
===================================================================
--- lld/COFF/Chunks.h
+++ lld/COFF/Chunks.h
@@ -47,7 +47,7 @@
 // doesn't even have actual data (if common or bss).
 class Chunk {
 public:
-  enum Kind { SectionKind, OtherKind };
+  enum Kind : uint8_t { SectionKind, OtherKind };
   Kind kind() const { return ChunkKind; }
   virtual ~Chunk() = default;
 
@@ -92,10 +92,33 @@
   // bytes, so this is used only for logging or debugging.
   virtual StringRef getDebugName() { return ""; }
 
+  // Returns true if the chunk was not dropped by GC or COMDAT deduplication.
+  bool isLive() { return Live && !Discarded; }
+
+  // Used by the garbage collector.
+  void markLive() {
+    assert(Config->DoGC && "should only mark things live from GC");
+    assert(!isLive() && "Cannot mark an already live section!");
+    Live = true;
+  }
+
+  // Returns true if this chunk was dropped by COMDAT deduplication.
+  bool isDiscarded() const { return Discarded; }
+
+  // Used by the SymbolTable when discarding unused comdat sections. This is
+  // redundant when GC is enabled, as all comdat sections will start out dead.
+  void markDiscarded() { Discarded = true; }
+
 protected:
   Chunk(Kind K = OtherKind) : ChunkKind(K) {}
   const Kind ChunkKind;
 
+  // True if this chunk was discarded because it was a duplicate comdat section.
+  bool Discarded;
+
+  // Used by the garbage collector.
+  bool Live;
+
   // The alignment of this chunk. The writer uses the value.
   uint32_t Align = 1;
 
@@ -155,28 +178,11 @@
 
   // Adds COMDAT associative sections to this COMDAT section. A chunk
   // and its children are treated as a group by the garbage collector.
-  void addAssociative(SectionChunk *Child);
+  void addAssociative(Chunk *Child);
 
   StringRef getDebugName() override;
   void setSymbol(DefinedRegular *S) { if (!Sym) Sym = S; }
 
-  // Returns true if the chunk was not dropped by GC or COMDAT deduplication.
-  bool isLive() { return Live && !Discarded; }
-
-  // Used by the garbage collector.
-  void markLive() {
-    assert(Config->DoGC && "should only mark things live from GC");
-    assert(!isLive() && "Cannot mark an already live section!");
-    Live = true;
-  }
-
-  // Returns true if this chunk was dropped by COMDAT deduplication.
-  bool isDiscarded() const { return Discarded; }
-
-  // Used by the SymbolTable when discarding unused comdat sections. This is
-  // redundant when GC is enabled, as all comdat sections will start out dead.
-  void markDiscarded() { Discarded = true; }
-
   // True if this is a codeview debug info chunk. These will not be laid out in
   // the image. Instead they will end up in the PDB, if one is requested.
   bool isCodeView() const {
@@ -190,7 +196,7 @@
   }
 
   // Allow iteration over the associated child chunks for this section.
-  ArrayRef<SectionChunk *> children() const { return AssocChildren; }
+  ArrayRef<Chunk *> children() const { return AssocChildren; }
 
   // A pointer pointing to a replacement for this chunk.
   // Initially it points to "this" object. If this chunk is merged
@@ -209,16 +215,10 @@
 
 private:
   StringRef SectionName;
-  std::vector<SectionChunk *> AssocChildren;
+  std::vector<Chunk *> AssocChildren;
   llvm::iterator_range<const coff_relocation *> Relocs;
   size_t NumRelocs;
 
-  // True if this chunk was discarded because it was a duplicate comdat section.
-  bool Discarded;
-
-  // Used by the garbage collector.
-  bool Live;
-
   // Used for ICF (Identical COMDAT Folding)
   void replace(SectionChunk *Other);
   uint32_t Class[2] = {0, 0};
Index: lld/COFF/Chunks.cpp
===================================================================
--- lld/COFF/Chunks.cpp
+++ lld/COFF/Chunks.cpp
@@ -176,7 +176,7 @@
   }
 }
 
-void SectionChunk::addAssociative(SectionChunk *Child) {
+void SectionChunk::addAssociative(Chunk *Child) {
   AssocChildren.push_back(Child);
 }
 
Index: lld/COFF/MarkLive.cpp
===================================================================
--- lld/COFF/MarkLive.cpp
+++ lld/COFF/MarkLive.cpp
@@ -59,8 +59,9 @@
       AddSym(B);
 
     // Mark associative sections if any.
-    for (SectionChunk *C : SC->children())
-      Enqueue(C);
+    for (Chunk *C : SC->children())
+      if (auto *SC = dyn_cast<SectionChunk>(C))
+        Enqueue(SC);
   }
 }
 
Index: lld/COFF/SymbolTable.cpp
===================================================================
--- lld/COFF/SymbolTable.cpp
+++ lld/COFF/SymbolTable.cpp
@@ -248,7 +248,7 @@
     C->markDiscarded();
     // Discard associative chunks that we've parsed so far. No need to recurse
     // because an associative section cannot have children.
-    for (SectionChunk *Child : C->children())
+    for (Chunk *Child : C->children())
       Child->markDiscarded();
   }
   return S;