[clang] [clang] Allow no trivial before C++ module directive (PR #153641)

[via cfe-commits]

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@@ -0,0 +1,388 @@
+//===--- TrivialDirectiveTracer.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
+//
+//===----------------------------------------------------------------------===//
+//
+//  This file defines the TrivialDirectiveTracer interface.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_LEX_TRIVIAL_DIRECTIVE_TRACER_H
+#define LLVM_CLANG_LEX_TRIVIAL_DIRECTIVE_TRACER_H
+
+#include "clang/Lex/PPCallbacks.h"
+
+namespace clang {
+class Preprocessor;
+
+class TrivialDirectiveTracer : public PPCallbacks {
+  Preprocessor &PP;
+  bool InMainFile = true;
+  bool SeenNoTrivialPPDirective = false;
+
+  void setSeenNoTrivialPPDirective(bool Val);
+
+public:
+  TrivialDirectiveTracer(Preprocessor &P) : PP(P) {}
+
+  bool hasSeenNoTrivialPPDirective() const;
+
+  /// Callback invoked whenever a source file is entered or exited.
+  ///
+  /// \param Loc Indicates the new location.
+  /// \param PrevFID the file that was exited if \p Reason is ExitFile or the
+  /// the file before the new one entered for \p Reason EnterFile.
+  void FileChanged(SourceLocation Loc, FileChangeReason Reason,
+                   SrcMgr::CharacteristicKind FileType,
+                   FileID PrevFID = FileID()) override;
+
+  /// Callback invoked whenever the \p Lexer moves to a different file for
+  /// lexing. Unlike \p FileChanged line number directives and other related
+  /// pragmas do not trigger callbacks to \p LexedFileChanged.
+  ///
+  /// \param FID The \p FileID that the \p Lexer moved to.
+  ///
+  /// \param Reason Whether the \p Lexer entered a new file or exited one.
+  ///
+  /// \param FileType The \p CharacteristicKind of the file the \p Lexer moved
+  /// to.
+  ///
+  /// \param PrevFID The \p FileID the \p Lexer was using before the change.
+  ///
+  /// \param Loc The location where the \p Lexer entered a new file from or the
+  /// location that the \p Lexer moved into after exiting a file.
+  void LexedFileChanged(FileID FID, LexedFileChangeReason Reason,
+                        SrcMgr::CharacteristicKind FileType, FileID PrevFID,
+                        SourceLocation Loc) override;
+
+  /// Callback invoked whenever an embed directive has been processed,
+  /// regardless of whether the embed will actually find a file.
+  ///
+  /// \param HashLoc The location of the '#' that starts the embed directive.
+  ///
+  /// \param FileName The name of the file being included, as written in the
+  /// source code.
+  ///
+  /// \param IsAngled Whether the file name was enclosed in angle brackets;
+  /// otherwise, it was enclosed in quotes.
+  ///
+  /// \param File The actual file that may be included by this embed directive.
+  ///
+  /// \param Params The parameters used by the directive.
+  void EmbedDirective(SourceLocation HashLoc, StringRef FileName, bool IsAngled,
+                      OptionalFileEntryRef File,
+                      const LexEmbedParametersResult &Params) override {
+    setSeenNoTrivialPPDirective(true);
+  }
+
+  /// Callback invoked whenever an inclusion directive of
+  /// any kind (\c \#include, \c \#import, etc.) has been processed, regardless
+  /// of whether the inclusion will actually result in an inclusion.
+  ///
+  /// \param HashLoc The location of the '#' that starts the inclusion
+  /// directive.
+  ///
+  /// \param IncludeTok The token that indicates the kind of inclusion
+  /// directive, e.g., 'include' or 'import'.
+  ///
+  /// \param FileName The name of the file being included, as written in the
+  /// source code.
+  ///
+  /// \param IsAngled Whether the file name was enclosed in angle brackets;
+  /// otherwise, it was enclosed in quotes.
+  ///
+  /// \param FilenameRange The character range of the quotes or angle brackets
+  /// for the written file name.
+  ///
+  /// \param File The actual file that may be included by this inclusion
+  /// directive.
+  ///
+  /// \param SearchPath Contains the search path which was used to find the file
+  /// in the file system. If the file was found via an absolute include path,
+  /// SearchPath will be empty. For framework includes, the SearchPath and
+  /// RelativePath will be split up. For example, if an include of "Some/Some.h"
+  /// is found via the framework path
+  /// "path/to/Frameworks/Some.framework/Headers/Some.h", SearchPath will be
+  /// "path/to/Frameworks/Some.framework/Headers" and RelativePath will be
+  /// "Some.h".
+  ///
+  /// \param RelativePath The path relative to SearchPath, at which the include
+  /// file was found. This is equal to FileName except for framework includes.
+  ///
+  /// \param SuggestedModule The module suggested for this header, if any.
+  ///
+  /// \param ModuleImported Whether this include was translated into import of
+  /// \p SuggestedModule.
+  ///
+  /// \param FileType The characteristic kind, indicates whether a file or
+  /// directory holds normal user code, system code, or system code which is
+  /// implicitly 'extern "C"' in C++ mode.
+  ///
+  void InclusionDirective(SourceLocation HashLoc, const Token &IncludeTok,
+                          StringRef FileName, bool IsAngled,
+                          CharSourceRange FilenameRange,
+                          OptionalFileEntryRef File, StringRef SearchPath,
+                          StringRef RelativePath, const Module *SuggestedModule,
+                          bool ModuleImported,
+                          SrcMgr::CharacteristicKind FileType) override {
+    setSeenNoTrivialPPDirective(true);
+  }
+
+  /// Callback invoked whenever there was an explicit module-import
+  /// syntax.
+  ///
+  /// \param ImportLoc The location of import directive token.
+  ///
+  /// \param Path The identifiers (and their locations) of the module
+  /// "path", e.g., "std.vector" would be split into "std" and "vector".
+  ///
+  /// \param Imported The imported module; can be null if importing failed.
+  ///
+  void moduleImport(SourceLocation ImportLoc, ModuleIdPath Path,
+                    const Module *Imported) override {
+    setSeenNoTrivialPPDirective(true);
+  }
+
+  /// Callback invoked when the end of the main file is reached.
+  ///
+  /// No subsequent callbacks will be made.
+  void EndOfMainFile() override { setSeenNoTrivialPPDirective(true); }
+
+  /// Callback invoked when a \#ident or \#sccs directive is read.
+  /// \param Loc The location of the directive.
+  /// \param str The text of the directive.
+  ///
+  void Ident(SourceLocation Loc, StringRef str) override {
+    setSeenNoTrivialPPDirective(false);
----------------
yronglin wrote:

Fixed.

https://github.com/llvm/llvm-project/pull/153641