Index: lldb/include/lldb/Symbol/SymbolFile.h
===================================================================
--- lldb/include/lldb/Symbol/SymbolFile.h
+++ lldb/include/lldb/Symbol/SymbolFile.h
@@ -161,6 +161,8 @@
                                         uint32_t line, bool check_inlines,
                                         lldb::SymbolContextItem resolve_scope,
                                         SymbolContextList &sc_list);
+
+  virtual void DumpClangAST() {}
   virtual uint32_t
   FindGlobalVariables(const ConstString &name,
                       const CompilerDeclContext *parent_decl_ctx,
Index: lldb/source/Commands/CommandObjectTarget.cpp
===================================================================
--- lldb/source/Commands/CommandObjectTarget.cpp
+++ lldb/source/Commands/CommandObjectTarget.cpp
@@ -2227,6 +2227,85 @@
   }
 };
 
+#pragma mark CommandObjectTargetModulesDumpSections
+
+//----------------------------------------------------------------------
+// Clang AST dumping command
+//----------------------------------------------------------------------
+
+class CommandObjectTargetModulesDumpClangAST
+  : public CommandObjectTargetModulesModuleAutoComplete {
+public:
+  CommandObjectTargetModulesDumpClangAST(CommandInterpreter &interpreter)
+    : CommandObjectTargetModulesModuleAutoComplete(
+      interpreter, "target modules dump ast",
+      "Dump the clang ast for a given module's symbol file.",
+      //"target modules dump ast [<file1> ...]")
+      nullptr) {}
+
+  ~CommandObjectTargetModulesDumpClangAST() override = default;
+
+protected:
+  bool DoExecute(Args &command, CommandReturnObject &result) override {
+    Target *target = m_interpreter.GetDebugger().GetSelectedTarget().get();
+    if (target == nullptr) {
+      result.AppendError("invalid target, create a debug target using the "
+        "'target create' command");
+      result.SetStatus(eReturnStatusFailed);
+      return false;
+    }
+
+    const size_t num_modules = target->GetImages().GetSize();
+    if (num_modules == 0) {
+      result.AppendError("the target has no associated executable images");
+      result.SetStatus(eReturnStatusFailed);
+      return false;
+    }
+
+    if (command.GetArgumentCount() == 0) {
+      // Dump all ASTs for all modules images
+      result.GetOutputStream().Printf("Dumping clang ast for %" PRIu64
+        " modules.\n",
+        (uint64_t)num_modules);
+      for (size_t image_idx = 0; image_idx < num_modules; ++image_idx) {
+        if (m_interpreter.WasInterrupted())
+          break;
+        Module *m = target->GetImages().GetModulePointerAtIndex(image_idx);
+        SymbolFile *sf = m->GetSymbolVendor()->GetSymbolFile();
+        sf->DumpClangAST();
+      }
+      result.SetStatus(eReturnStatusSuccessFinishResult);
+      return true;
+    }
+
+    // Dump specified ASTs (by basename or fullpath)
+    for (const Args::ArgEntry &arg : command.entries()) {
+      ModuleList module_list;
+      const size_t num_matches =
+        FindModulesByName(target, arg.c_str(), module_list, true);
+      if (num_matches == 0) {
+        // Check the global list
+        std::lock_guard<std::recursive_mutex> guard(
+          Module::GetAllocationModuleCollectionMutex());
+
+        result.AppendWarningWithFormat(
+          "Unable to find an image that matches '%s'.\n", arg.c_str());
+        continue;
+      }
+
+      for (size_t i = 0; i < num_matches; ++i) {
+        if (m_interpreter.WasInterrupted())
+          break;
+        Module *m = module_list.GetModulePointerAtIndex(i);
+        SymbolFile *sf = m->GetSymbolVendor()->GetSymbolFile();
+        sf->DumpClangAST();
+      }
+    }
+    result.SetStatus(eReturnStatusSuccessFinishResult);
+    return true;
+  }
+};
+
 #pragma mark CommandObjectTargetModulesDumpSymfile
 
 //----------------------------------------------------------------------
@@ -2406,7 +2485,7 @@
                                "Commands for dumping information about one or "
                                "more target modules.",
                                "target modules dump "
-                               "[headers|symtab|sections|symfile|line-table] "
+                               "[headers|symtab|sections|ast|symfile|line-table] "
                                "[<file1> <file2> ...]") {
     LoadSubCommand("objfile",
                    CommandObjectSP(
@@ -2420,6 +2499,9 @@
     LoadSubCommand("symfile",
                    CommandObjectSP(
                        new CommandObjectTargetModulesDumpSymfile(interpreter)));
+    LoadSubCommand("ast",
+      CommandObjectSP(new CommandObjectTargetModulesDumpClangAST(
+        interpreter)));
     LoadSubCommand("line-table",
                    CommandObjectSP(new CommandObjectTargetModulesDumpLineTable(
                        interpreter)));
Index: lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.h
===================================================================
--- lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.h
+++ lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.h
@@ -329,6 +329,8 @@
 
   void Dump(lldb_private::Stream &s) override;
 
+  void DumpClangAST() override;
+
 protected:
   typedef llvm::DenseMap<const DWARFDebugInfoEntry *, lldb_private::Type *>
       DIEToTypePtr;
Index: lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp
===================================================================
--- lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp
+++ lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp
@@ -3854,6 +3854,18 @@
 
 void SymbolFileDWARF::Dump(lldb_private::Stream &s) { m_index->Dump(s); }
 
+void SymbolFileDWARF::DumpClangAST() {
+  TypeSystem *ts = GetTypeSystemForLanguage(eLanguageTypeC_plus_plus);
+  ClangASTContext *clang = llvm::dyn_cast_or_null<ClangASTContext>(ts);
+  if (!clang)
+    return;
+  clang::TranslationUnitDecl *tu = clang->getASTContext()->getTranslationUnitDecl();
+  if (llvm::errs().has_colors())
+    tu->dumpColor();
+  else
+    tu->dump();
+}
+
 SymbolFileDWARFDebugMap *SymbolFileDWARF::GetDebugMapSymfile() {
   if (m_debug_map_symfile == NULL && !m_debug_map_module_wp.expired()) {
     lldb::ModuleSP module_sp(m_debug_map_module_wp.lock());
Index: lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDebugMap.h
===================================================================
--- lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDebugMap.h
+++ lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDebugMap.h
@@ -126,6 +126,8 @@
   std::vector<lldb_private::CallEdge>
   ParseCallEdgesInFunction(lldb_private::UserID func_id) override;
 
+  void DumpClangAST() override;
+
   //------------------------------------------------------------------
   // PluginInterface protocol
   //------------------------------------------------------------------
Index: lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDebugMap.cpp
===================================================================
--- lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDebugMap.cpp
+++ lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDebugMap.cpp
@@ -1227,6 +1227,13 @@
   return matching_namespace;
 }
 
+void SymbolFileDWARFDebugMap::DumpClangAST() {
+  ForEachSymbolFile([](SymbolFileDWARF *oso_dwarf) -> bool {
+    oso_dwarf->DumpClangAST();
+    return true;
+  });
+}
+
 //------------------------------------------------------------------
 // PluginInterface protocol
 //------------------------------------------------------------------
Index: lldb/source/Plugins/SymbolFile/NativePDB/SymbolFileNativePDB.h
===================================================================
--- lldb/source/Plugins/SymbolFile/NativePDB/SymbolFileNativePDB.h
+++ lldb/source/Plugins/SymbolFile/NativePDB/SymbolFileNativePDB.h
@@ -155,6 +155,8 @@
   ClangASTContext &GetASTContext() { return *m_clang; }
   ClangASTImporter &GetASTImporter() { return *m_importer; }
 
+  void DumpClangAST() override;
+
 private:
   size_t FindTypesByName(llvm::StringRef name, uint32_t max_matches,
                          TypeMap &types);
Index: lldb/source/Plugins/SymbolFile/NativePDB/SymbolFileNativePDB.cpp
===================================================================
--- lldb/source/Plugins/SymbolFile/NativePDB/SymbolFileNativePDB.cpp
+++ lldb/source/Plugins/SymbolFile/NativePDB/SymbolFileNativePDB.cpp
@@ -1391,6 +1391,17 @@
   return 0;
 }
 
+void SymbolFileNativePDB::DumpClangAST() {
+  if (!m_clang)
+    return;
+  
+  clang::TranslationUnitDecl *tu = m_clang->getASTContext()->getTranslationUnitDecl();
+  if (llvm::errs().has_colors())
+    tu->dumpColor();
+  else
+    tu->dump();
+}
+
 uint32_t SymbolFileNativePDB::FindGlobalVariables(
     const ConstString &name, const CompilerDeclContext *parent_decl_ctx,
     uint32_t max_matches, VariableList &variables) {
Index: lldb/source/Plugins/SymbolFile/PDB/SymbolFilePDB.h
===================================================================
--- lldb/source/Plugins/SymbolFile/PDB/SymbolFilePDB.h
+++ lldb/source/Plugins/SymbolFile/PDB/SymbolFilePDB.h
@@ -169,6 +169,8 @@
 
   const llvm::pdb::IPDBSession &GetPDBSession() const;
 
+  void DumpClangAST() override;
+
 private:
   struct SecContribInfo {
     uint32_t Offset;
Index: lldb/source/Plugins/SymbolFile/PDB/SymbolFilePDB.cpp
===================================================================
--- lldb/source/Plugins/SymbolFile/PDB/SymbolFilePDB.cpp
+++ lldb/source/Plugins/SymbolFile/PDB/SymbolFilePDB.cpp
@@ -1356,6 +1356,18 @@
   return types.GetSize();
 }
 
+void SymbolFilePDB::DumpClangAST() {
+  auto type_system = GetTypeSystemForLanguage(lldb::eLanguageTypeC_plus_plus);
+  auto clang = llvm::dyn_cast_or_null<ClangASTContext>(type_system);
+  if (!clang)
+    return;
+  clang::TranslationUnitDecl *tu = clang->getASTContext()->getTranslationUnitDecl();
+  if (llvm::errs().has_colors())
+    tu->dumpColor();
+  else
+    tu->dump();
+}
+
 void SymbolFilePDB::FindTypesByRegex(
     const lldb_private::RegularExpression &regex, uint32_t max_matches,
     lldb_private::TypeMap &types) {