From 4fc55a76b8d28335d2b57fe083bcc165c0061dab Mon Sep 17 00:00:00 2001 From: Krasimir Georgiev Date: Tue, 12 Jun 2018 19:33:15 +0000 Subject: [clang-format] Fix crash while reflowing backslash in comments Summary: The added test case was currently crashing with an assertion: ``` krasimir@krasimir> cat test.cc ~ // How to run: // bbbbb run \ // rrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrr \ // -- --output_directory="" krasimir@krasimir> ~/work/llvm-build/bin/clang-format test.cc ~ clang-format: /usr/local/google/home/krasimir/work/llvm/tools/clang/lib/Format/WhitespaceManager.cpp:117: void clang::format::WhitespaceManager::calculateLineBreakInformation(): Assertion `PreviousOriginalWhitespaceEndOffset <= OriginalWhitespaceStartOffset' failed. ``` The root cause was that BreakableToken was not considering the case of a reflow between an unescaped newline in a line comment. Subscribers: cfe-commits Differential Revision: https://reviews.llvm.org/D48089 llvm-svn: 334527 --- clang/lib/Format/BreakableToken.cpp | 45 +++++++++++++++++++++++++++++++------ 1 file changed, 38 insertions(+), 7 deletions(-) (limited to 'clang/lib/Format') diff --git a/clang/lib/Format/BreakableToken.cpp b/clang/lib/Format/BreakableToken.cpp index f727f8ddf89..cc68f70100e 100644 --- a/clang/lib/Format/BreakableToken.cpp +++ b/clang/lib/Format/BreakableToken.cpp @@ -789,16 +789,47 @@ BreakableComment::Split BreakableLineCommentSection::getReflowSplit( void BreakableLineCommentSection::reflow(unsigned LineIndex, WhitespaceManager &Whitespaces) const { - // Reflow happens between tokens. Replace the whitespace between the - // tokens by the empty string. - Whitespaces.replaceWhitespace( - *Tokens[LineIndex], /*Newlines=*/0, /*Spaces=*/0, - /*StartOfTokenColumn=*/StartColumn, /*InPPDirective=*/false); + if (LineIndex > 0 && Tokens[LineIndex] != Tokens[LineIndex - 1]) { + // Reflow happens between tokens. Replace the whitespace between the + // tokens by the empty string. + Whitespaces.replaceWhitespace( + *Tokens[LineIndex], /*Newlines=*/0, /*Spaces=*/0, + /*StartOfTokenColumn=*/StartColumn, /*InPPDirective=*/false); + } else if (LineIndex > 0) { + // In case we're reflowing after the '\' in: + // + // // line comment \ + // // line 2 + // + // the reflow happens inside the single comment token (it is a single line + // comment with an unescaped newline). + // Replace the whitespace between the '\' and '//' with the empty string. + // + // Offset points to after the '\' relative to start of the token. + unsigned Offset = Lines[LineIndex - 1].data() + + Lines[LineIndex - 1].size() - + tokenAt(LineIndex - 1).TokenText.data(); + // WhitespaceLength is the number of chars between the '\' and the '//' on + // the next line. + unsigned WhitespaceLength = + Lines[LineIndex].data() - tokenAt(LineIndex).TokenText.data() - Offset; + Whitespaces.replaceWhitespaceInToken(*Tokens[LineIndex], + Offset, + /*ReplaceChars=*/WhitespaceLength, + /*PreviousPostfix=*/"", + /*CurrentPrefix=*/"", + /*InPPDirective=*/false, + /*Newlines=*/0, + /*Spaces=*/0); + + } // Replace the indent and prefix of the token with the reflow prefix. + unsigned Offset = + Lines[LineIndex].data() - tokenAt(LineIndex).TokenText.data(); unsigned WhitespaceLength = - Content[LineIndex].data() - tokenAt(LineIndex).TokenText.data(); + Content[LineIndex].data() - Lines[LineIndex].data(); Whitespaces.replaceWhitespaceInToken(*Tokens[LineIndex], - /*Offset=*/0, + Offset, /*ReplaceChars=*/WhitespaceLength, /*PreviousPostfix=*/"", /*CurrentPrefix=*/ReflowPrefix, -- cgit v1.2.3