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diff --git a/lldb/source/Plugins/ExpressionParser/Clang/CppModuleConfiguration.h b/lldb/source/Plugins/ExpressionParser/Clang/CppModuleConfiguration.h
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+++ b/lldb/source/Plugins/ExpressionParser/Clang/CppModuleConfiguration.h
@@ -0,0 +1,84 @@
+//===-- CppModuleConfiguration.h --------------------------------*- C++ -*-===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef liblldb_CppModuleConfiguration_h_
+#define liblldb_CppModuleConfiguration_h_
+
+#include <lldb/Core/FileSpecList.h>
+#include <llvm/Support/Regex.h>
+
+namespace lldb_private {
+
+/// A Clang configuration when importing C++ modules.
+///
+/// Includes a list of include paths that should be used when importing
+/// and a list of modules that can be imported. Currently only used when
+/// importing the 'std' module and its dependencies.
+class CppModuleConfiguration {
+  /// Utility class for a path that can only be set once.
+  class SetOncePath {
+    std::string m_path;
+    bool m_valid = false;
+    /// True iff this path hasn't been set yet.
+    bool m_first = true;
+
+  public:
+    /// Try setting the path. Returns true if the path was set and false if
+    /// the path was already set.
+    LLVM_NODISCARD bool TrySet(llvm::StringRef path);
+    /// Return the path if there is one.
+    std::string Get() const {
+      assert(m_valid && "Called Get() on an invalid SetOncePath?");
+      return m_path;
+    }
+    /// Returns true iff this path was set exactly once so far.
+    bool Valid() const { return m_valid; }
+  };
+
+  /// If valid, the include path used for the std module.
+  SetOncePath m_std_inc;
+  /// If valid, the include path to the C library (e.g. /usr/include).
+  SetOncePath m_c_inc;
+  /// The Clang resource include path for this configuration.
+  std::string m_resource_inc;
+
+  std::vector<std::string> m_include_dirs;
+  std::vector<std::string> m_imported_modules;
+
+  /// Analyze a given source file to build the current configuration.
+  /// Returns false iff there was a fatal error that makes analyzing any
+  /// further files pointless as the configuration is now invalid.
+  bool analyzeFile(const FileSpec &f);
+
+public:
+  /// Creates a configuraiton by analyzing the given list of used source files.
+  ///
+  /// Currently only looks at the used paths and doesn't actually access the
+  /// files on the disk.
+  explicit CppModuleConfiguration(const FileSpecList &support_files);
+  /// Creates an empty and invalid configuration.
+  CppModuleConfiguration() {}
+
+  /// Returns true iff this is a valid configuration that can be used to
+  /// load and compile modules.
+  bool hasValidConfig();
+
+  /// Returns a list of include directories that should be used when using this
+  /// configuration (e.g. {"/usr/include", "/usr/include/c++/v1"}).
+  llvm::ArrayRef<std::string> GetIncludeDirs() const { return m_include_dirs; }
+
+  /// Returns a list of (top level) modules that should be imported when using
+  /// this configuration (e.g. {"std"}).
+  llvm::ArrayRef<std::string> GetImportedModules() const {
+    return m_imported_modules;
+  }
+};
+
+} // namespace lldb_private
+
+#endif