diff --git a/lldb/include/lldb/Expression/UserExpression.h b/lldb/include/lldb/Expression/UserExpression.h
--- a/lldb/include/lldb/Expression/UserExpression.h
+++ b/lldb/include/lldb/Expression/UserExpression.h
@@ -33,7 +33,7 @@
 /// implementations of UserExpression - which will be vended through the
 /// appropriate TypeSystem.
 class UserExpression : public Expression {
-  // LLVM RTTI support
+  /// LLVM RTTI support.
   static char ID;
 
 public:
diff --git a/lldb/include/lldb/Symbol/SymbolFile.h b/lldb/include/lldb/Symbol/SymbolFile.h
--- a/lldb/include/lldb/Symbol/SymbolFile.h
+++ b/lldb/include/lldb/Symbol/SymbolFile.h
@@ -33,7 +33,16 @@
 namespace lldb_private {
 
 class SymbolFile : public PluginInterface {
+  /// LLVM RTTI support.
+  static char ID;
+
 public:
+  /// LLVM RTTI support.
+  /// \{
+  virtual bool isA(const void *ClassID) const { return ClassID == &ID; }
+  static bool classof(const SymbolFile *obj) { return obj->isA(&ID); }
+  /// \}
+
   // Symbol file ability bits.
   //
   // Each symbol file can claim to support one or more symbol file abilities.
diff --git a/lldb/source/Plugins/SymbolFile/Breakpad/SymbolFileBreakpad.h b/lldb/source/Plugins/SymbolFile/Breakpad/SymbolFileBreakpad.h
--- a/lldb/source/Plugins/SymbolFile/Breakpad/SymbolFileBreakpad.h
+++ b/lldb/source/Plugins/SymbolFile/Breakpad/SymbolFileBreakpad.h
@@ -21,7 +21,18 @@
 namespace breakpad {
 
 class SymbolFileBreakpad : public SymbolFile {
+  /// LLVM RTTI support.
+  static char ID;
+
 public:
+  /// LLVM RTTI support.
+  /// \{
+  bool isA(const void *ClassID) const override {
+    return ClassID == &ID || SymbolFile::isA(ClassID);
+  }
+  static bool classof(const SymbolFile *obj) { return obj->isA(&ID); }
+  /// \}
+
   // Static Functions
   static void Initialize();
   static void Terminate();
diff --git a/lldb/source/Plugins/SymbolFile/Breakpad/SymbolFileBreakpad.cpp b/lldb/source/Plugins/SymbolFile/Breakpad/SymbolFileBreakpad.cpp
--- a/lldb/source/Plugins/SymbolFile/Breakpad/SymbolFileBreakpad.cpp
+++ b/lldb/source/Plugins/SymbolFile/Breakpad/SymbolFileBreakpad.cpp
@@ -25,6 +25,8 @@
 using namespace lldb_private;
 using namespace lldb_private::breakpad;
 
+char SymbolFileBreakpad::ID;
+
 class SymbolFileBreakpad::LineIterator {
 public:
   // begin iterator for sections of given type
diff --git a/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.h b/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.h
--- a/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.h
+++ b/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.h
@@ -59,7 +59,18 @@
 
 class SymbolFileDWARF : public lldb_private::SymbolFile,
                         public lldb_private::UserID {
+  /// LLVM RTTI support.
+  static char ID;
+
 public:
+  /// LLVM RTTI support.
+  /// \{
+  bool isA(const void *ClassID) const override {
+    return ClassID == &ID || SymbolFile::isA(ClassID);
+  }
+  static bool classof(const SymbolFile *obj) { return obj->isA(&ID); }
+  /// \}
+
   friend class SymbolFileDWARFDebugMap;
   friend class SymbolFileDWARFDwo;
   friend class DebugMapModule;
diff --git a/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp b/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp
--- a/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp
+++ b/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp
@@ -94,6 +94,8 @@
 using namespace lldb;
 using namespace lldb_private;
 
+char SymbolFileDWARF::ID;
+
 // static inline bool
 // child_requires_parent_class_union_or_struct_to_be_completed (dw_tag_t tag)
 //{
diff --git a/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDebugMap.h b/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDebugMap.h
--- a/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDebugMap.h
+++ b/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDebugMap.h
@@ -23,7 +23,18 @@
 class DWARFDeclContext;
 
 class SymbolFileDWARFDebugMap : public lldb_private::SymbolFile {
+  /// LLVM RTTI support.
+  static char ID;
+
 public:
+  /// LLVM RTTI support.
+  /// \{
+  bool isA(const void *ClassID) const override {
+    return ClassID == &ID || SymbolFile::isA(ClassID);
+  }
+  static bool classof(const SymbolFile *obj) { return obj->isA(&ID); }
+  /// \}
+
   // Static Functions
   static void Initialize();
 
diff --git a/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDebugMap.cpp b/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDebugMap.cpp
--- a/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDebugMap.cpp
+++ b/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDebugMap.cpp
@@ -39,6 +39,8 @@
 using namespace lldb;
 using namespace lldb_private;
 
+char SymbolFileDWARFDebugMap::ID;
+
 // Subclass lldb_private::Module so we can intercept the
 // "Module::GetObjectFile()" (so we can fixup the object file sections) and
 // also for "Module::GetSymbolFile()" (so we can fixup the symbol file id.
diff --git a/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDwo.h b/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDwo.h
--- a/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDwo.h
+++ b/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDwo.h
@@ -12,7 +12,18 @@
 #include "SymbolFileDWARF.h"
 
 class SymbolFileDWARFDwo : public SymbolFileDWARF {
+  /// LLVM RTTI support.
+  static char ID;
+
 public:
+  /// LLVM RTTI support.
+  /// \{
+  bool isA(const void *ClassID) const override {
+    return ClassID == &ID || SymbolFileDWARF::isA(ClassID);
+  }
+  static bool classof(const SymbolFile *obj) { return obj->isA(&ID); }
+  /// \}
+
   SymbolFileDWARFDwo(lldb::ObjectFileSP objfile, DWARFCompileUnit &dwarf_cu);
 
   ~SymbolFileDWARFDwo() override = default;
diff --git a/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDwo.cpp b/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDwo.cpp
--- a/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDwo.cpp
+++ b/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDwo.cpp
@@ -21,6 +21,8 @@
 using namespace lldb;
 using namespace lldb_private;
 
+char SymbolFileDWARFDwo::ID;
+
 SymbolFileDWARFDwo::SymbolFileDWARFDwo(ObjectFileSP objfile,
                                        DWARFCompileUnit &dwarf_cu)
     : SymbolFileDWARF(objfile, objfile->GetSectionList(
diff --git a/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDwoDwp.h b/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDwoDwp.h
--- a/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDwoDwp.h
+++ b/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDwoDwp.h
@@ -13,7 +13,17 @@
 #include "SymbolFileDWARFDwp.h"
 
 class SymbolFileDWARFDwoDwp : public SymbolFileDWARFDwo {
+  /// LLVM RTTI support.
+  static char ID;
+
 public:
+  /// LLVM RTTI support.
+  /// \{
+  bool isA(const void *ClassID) const override {
+    return ClassID == &ID || SymbolFileDWARFDwo::isA(ClassID);
+  }
+  static bool classof(const SymbolFile *obj) { return obj->isA(&ID); }
+  /// \}
   SymbolFileDWARFDwoDwp(SymbolFileDWARFDwp *dwp_symfile,
                         lldb::ObjectFileSP objfile, DWARFCompileUnit &dwarf_cu,
                         uint64_t dwo_id);
diff --git a/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDwoDwp.cpp b/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDwoDwp.cpp
--- a/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDwoDwp.cpp
+++ b/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDwoDwp.cpp
@@ -19,6 +19,8 @@
 using namespace lldb;
 using namespace lldb_private;
 
+char SymbolFileDWARFDwoDwp::ID;
+
 SymbolFileDWARFDwoDwp::SymbolFileDWARFDwoDwp(SymbolFileDWARFDwp *dwp_symfile,
                                              ObjectFileSP objfile,
                                              DWARFCompileUnit &dwarf_cu,
diff --git a/lldb/source/Plugins/SymbolFile/NativePDB/SymbolFileNativePDB.h b/lldb/source/Plugins/SymbolFile/NativePDB/SymbolFileNativePDB.h
--- a/lldb/source/Plugins/SymbolFile/NativePDB/SymbolFileNativePDB.h
+++ b/lldb/source/Plugins/SymbolFile/NativePDB/SymbolFileNativePDB.h
@@ -41,7 +41,18 @@
 class SymbolFileNativePDB : public SymbolFile {
   friend class UdtRecordCompleter;
 
+  /// LLVM RTTI support.
+  static char ID;
+
 public:
+  /// LLVM RTTI support.
+  /// \{
+  bool isA(const void *ClassID) const override {
+    return ClassID == &ID || SymbolFile::isA(ClassID);
+  }
+  static bool classof(const SymbolFile *obj) { return obj->isA(&ID); }
+  /// \}
+
   // Static Functions
   static void Initialize();
 
diff --git a/lldb/source/Plugins/SymbolFile/NativePDB/SymbolFileNativePDB.cpp b/lldb/source/Plugins/SymbolFile/NativePDB/SymbolFileNativePDB.cpp
--- a/lldb/source/Plugins/SymbolFile/NativePDB/SymbolFileNativePDB.cpp
+++ b/lldb/source/Plugins/SymbolFile/NativePDB/SymbolFileNativePDB.cpp
@@ -67,6 +67,8 @@
 using namespace llvm::codeview;
 using namespace llvm::pdb;
 
+char SymbolFileNativePDB::ID;
+
 static lldb::LanguageType TranslateLanguage(PDB_Lang lang) {
   switch (lang) {
   case PDB_Lang::Cpp:
diff --git a/lldb/source/Plugins/SymbolFile/PDB/SymbolFilePDB.h b/lldb/source/Plugins/SymbolFile/PDB/SymbolFilePDB.h
--- a/lldb/source/Plugins/SymbolFile/PDB/SymbolFilePDB.h
+++ b/lldb/source/Plugins/SymbolFile/PDB/SymbolFilePDB.h
@@ -22,7 +22,18 @@
 class PDBASTParser;
 
 class SymbolFilePDB : public lldb_private::SymbolFile {
+  /// LLVM RTTI support.
+  static char ID;
+
 public:
+  /// LLVM RTTI support.
+  /// \{
+  bool isA(const void *ClassID) const override {
+    return ClassID == &ID || SymbolFile::isA(ClassID);
+  }
+  static bool classof(const SymbolFile *obj) { return obj->isA(&ID); }
+  /// \}
+
   // Static Functions
   static void Initialize();
 
diff --git a/lldb/source/Plugins/SymbolFile/PDB/SymbolFilePDB.cpp b/lldb/source/Plugins/SymbolFile/PDB/SymbolFilePDB.cpp
--- a/lldb/source/Plugins/SymbolFile/PDB/SymbolFilePDB.cpp
+++ b/lldb/source/Plugins/SymbolFile/PDB/SymbolFilePDB.cpp
@@ -58,6 +58,8 @@
 using namespace lldb_private;
 using namespace llvm::pdb;
 
+char SymbolFilePDB::ID;
+
 namespace {
 lldb::LanguageType TranslateLanguage(PDB_Lang lang) {
   switch (lang) {
diff --git a/lldb/source/Plugins/SymbolFile/Symtab/SymbolFileSymtab.h b/lldb/source/Plugins/SymbolFile/Symtab/SymbolFileSymtab.h
--- a/lldb/source/Plugins/SymbolFile/Symtab/SymbolFileSymtab.h
+++ b/lldb/source/Plugins/SymbolFile/Symtab/SymbolFileSymtab.h
@@ -16,7 +16,18 @@
 #include "lldb/Symbol/Symtab.h"
 
 class SymbolFileSymtab : public lldb_private::SymbolFile {
+  /// LLVM RTTI support.
+  static char ID;
+
 public:
+  /// LLVM RTTI support.
+  /// \{
+  bool isA(const void *ClassID) const override {
+    return ClassID == &ID || SymbolFile::isA(ClassID);
+  }
+  static bool classof(const SymbolFile *obj) { return obj->isA(&ID); }
+  /// \}
+
   // Constructors and Destructors
   SymbolFileSymtab(lldb::ObjectFileSP objfile_sp);
 
diff --git a/lldb/source/Plugins/SymbolFile/Symtab/SymbolFileSymtab.cpp b/lldb/source/Plugins/SymbolFile/Symtab/SymbolFileSymtab.cpp
--- a/lldb/source/Plugins/SymbolFile/Symtab/SymbolFileSymtab.cpp
+++ b/lldb/source/Plugins/SymbolFile/Symtab/SymbolFileSymtab.cpp
@@ -25,6 +25,8 @@
 using namespace lldb;
 using namespace lldb_private;
 
+char SymbolFileSymtab::ID;
+
 void SymbolFileSymtab::Initialize() {
   PluginManager::RegisterPlugin(GetPluginNameStatic(),
                                 GetPluginDescriptionStatic(), CreateInstance);
diff --git a/lldb/source/Symbol/SymbolFile.cpp b/lldb/source/Symbol/SymbolFile.cpp
--- a/lldb/source/Symbol/SymbolFile.cpp
+++ b/lldb/source/Symbol/SymbolFile.cpp
@@ -24,6 +24,8 @@
 using namespace lldb_private;
 using namespace lldb;
 
+char SymbolFile::ID;
+
 void SymbolFile::PreloadSymbols() {
   // No-op for most implementations.
 }