From cf2c2e9588a12a716615850cc5bfacd9b20f68ef Mon Sep 17 00:00:00 2001 From: Jordan Rose Date: Tue, 5 Mar 2013 23:54:55 +0000 Subject: [PATCH] Preprocessor: don't keep comments under -traditional-cpp. This patch is designed for minimal intrusion into normal preprocessing and compilation; under -E -traditional-cpp, the lexer will still generate tok::comment nodes since it is preserving all whitespace, but the output printer will then throw it away. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@176534 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Frontend/PrintPreprocessedOutput.cpp | 11 ++++++++++- test/Preprocessor/traditional-cpp.c | 6 ++++++ 2 files changed, 16 insertions(+), 1 deletion(-) diff --git a/lib/Frontend/PrintPreprocessedOutput.cpp b/lib/Frontend/PrintPreprocessedOutput.cpp index 58bbfd3f8a..d894939b4b 100644 --- a/lib/Frontend/PrintPreprocessedOutput.cpp +++ b/lib/Frontend/PrintPreprocessedOutput.cpp @@ -515,6 +515,9 @@ struct UnknownPragmaHandler : public PragmaHandler { static void PrintPreprocessedTokens(Preprocessor &PP, Token &Tok, PrintPPOutputPPCallbacks *Callbacks, raw_ostream &OS) { + bool DropComments = PP.getLangOpts().TraditionalCPP && + !PP.getCommentRetentionState(); + char Buffer[256]; Token PrevPrevTok, PrevTok; PrevPrevTok.startToken(); @@ -537,7 +540,13 @@ static void PrintPreprocessedTokens(Preprocessor &PP, Token &Tok, OS << ' '; } - if (IdentifierInfo *II = Tok.getIdentifierInfo()) { + if (DropComments && Tok.is(tok::comment)) { + // Skip comments. Normally the preprocessor does not generate + // tok::comment nodes at all when not keeping comments, but under + // -traditional-cpp the lexer keeps /all/ whitespace, including comments. + SourceLocation StartLoc = Tok.getLocation(); + Callbacks->MoveToLine(StartLoc.getLocWithOffset(Tok.getLength())); + } else if (IdentifierInfo *II = Tok.getIdentifierInfo()) { OS << II->getName(); } else if (Tok.isLiteral() && !Tok.needsCleaning() && Tok.getLiteralData()) { diff --git a/test/Preprocessor/traditional-cpp.c b/test/Preprocessor/traditional-cpp.c index 0396c9b126..4c4633e039 100644 --- a/test/Preprocessor/traditional-cpp.c +++ b/test/Preprocessor/traditional-cpp.c @@ -5,8 +5,14 @@ /* RUN: %clang_cc1 -traditional-cpp %s -E -o %t RUN: FileCheck -strict-whitespace < %t %s + RUN: %clang_cc1 -traditional-cpp %s -E -C | FileCheck -check-prefix=CHECK-COMMENTS %s */ +/* -traditional-cpp should eliminate all C89 comments. */ +/* CHECK-NOT: /* + * CHECK-COMMENTS: {{^}}/* -traditional-cpp should eliminate all C89 comments. *{{/$}} + */ + /* CHECK: {{^}}foo // bar{{$}} */ foo // bar -- 2.40.0