llvm/clang-tools-extra/modularize/PreprocessorTracker.h

//===- PreprocessorTracker.h - Tracks preprocessor activities -*- 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
//
//===--------------------------------------------------------------------===//
///
/// \file
/// Macro expansions and preprocessor conditional consistency checker.
///
//===--------------------------------------------------------------------===//

#ifndef MODULARIZE_PREPROCESSOR_TRACKER_H
#define MODULARIZE_PREPROCESSOR_TRACKER_H

#include "clang/Lex/Preprocessor.h"

namespace Modularize {

/// Preprocessor tracker for modularize.
///
/// The PreprocessorTracker class defines an API for
/// checking macro expansions and preprocessor conditional expressions
/// in a header file for consistency among one or more compilations of
/// the header in a #include scenario.  This is for helping a user
/// find which macro expansions or conditionals might be problematic with
/// respect to using the headers in the modules scenario, because they
/// evaluate to different values depending on how or where a header
/// is included.
///
/// The handlePreprocessorEntry function implementation will register
/// a PPCallbacks object in the given Preprocessor object.  The calls to
/// the callbacks will collect information about the macro expansions
/// and preprocessor conditionals encountered, for later analysis and
/// reporting of inconsistencies between runs performed by calls to
/// the reportInconsistentMacros and reportInconsistentConditionals
/// functions respectively.  The handlePreprocessorExit informs the
/// implementation that a preprocessing session is complete, allowing
/// it to do any needed compilation completion activities in the checker.
class PreprocessorTracker { … };

} // end namespace Modularize

#endif