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.
<rdar://problem/13338680>
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@176534 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Frontend/PrintPreprocessedOutput.cpp b/lib/Frontend/PrintPreprocessedOutput.cpp
index 58bbfd3..d894939 100644
--- a/lib/Frontend/PrintPreprocessedOutput.cpp
+++ b/lib/Frontend/PrintPreprocessedOutput.cpp
@@ -515,6 +515,9 @@
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 @@
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()) {