https://github.com/yronglin updated https://github.com/llvm/llvm-project/pull/203716
>From d2a6eaa165128c9cc32447dcbfd36413c758d35b Mon Sep 17 00:00:00 2001 From: yronglin <[email protected]> Date: Sat, 13 Jun 2026 09:56:56 -0700 Subject: [PATCH 1/3] [clangd] Fix clangd crash when code completion EOF is reached while skipping a function body Signed-off-by: yronglin <[email protected]> --- .../clangd/unittests/CodeCompleteTests.cpp | 17 +++++++++++++++++ clang/lib/Parse/ParseStmt.cpp | 14 +++++--------- 2 files changed, 22 insertions(+), 9 deletions(-) diff --git a/clang-tools-extra/clangd/unittests/CodeCompleteTests.cpp b/clang-tools-extra/clangd/unittests/CodeCompleteTests.cpp index 5808b2145965f..dc94af4dddf8c 100644 --- a/clang-tools-extra/clangd/unittests/CodeCompleteTests.cpp +++ b/clang-tools-extra/clangd/unittests/CodeCompleteTests.cpp @@ -1918,6 +1918,23 @@ TEST(SignatureHelpTest, StalePreamble) { EXPECT_EQ(0, Results.activeParameter); } +TEST(SignatureHelpTest, EOFInSkippedFunctionBody) { + Annotations Test(R"cpp( +#ifdef IS_HEADER +void frameSizeBlocksWarning() { + auto fn = []() { + }; + fn(); +} +#else +#define IS_HEADER +#include __FILE__ +#^endif +)cpp"); + auto Results = signatures(Test.code(), Test.point()); + EXPECT_THAT(Results.signatures, IsEmpty()); +} + class IndexRequestCollector : public SymbolIndex { public: IndexRequestCollector(std::vector<Symbol> Syms = {}) : Symbols(Syms) {} diff --git a/clang/lib/Parse/ParseStmt.cpp b/clang/lib/Parse/ParseStmt.cpp index 37f142e059930..e77d6066847b2 100644 --- a/clang/lib/Parse/ParseStmt.cpp +++ b/clang/lib/Parse/ParseStmt.cpp @@ -2496,8 +2496,10 @@ bool Parser::trySkippingFunctionBody() { // We're in code-completion mode. Skip parsing for all function bodies unless // the body contains the code-completion point. + if (Tok.is(tok::kw_try)) + return false; + TentativeParsingAction PA(*this); - bool IsTryCatch = Tok.is(tok::kw_try); CachedTokens Toks; bool ErrorInPrologue = ConsumeAndStoreFunctionPrologue(Toks); if (llvm::any_of(Toks, [](const Token &Tok) { @@ -2511,18 +2513,12 @@ bool Parser::trySkippingFunctionBody() { SkipMalformedDecl(); return true; } - if (!SkipUntil(tok::r_brace, StopAtCodeCompletion)) { + if (!SkipUntil(tok::r_brace, StopAtCodeCompletion | StopBeforeMatch)) { PA.Revert(); return false; } - while (IsTryCatch && Tok.is(tok::kw_catch)) { - if (!SkipUntil(tok::l_brace, StopAtCodeCompletion) || - !SkipUntil(tok::r_brace, StopAtCodeCompletion)) { - PA.Revert(); - return false; - } - } PA.Commit(); + ConsumeBrace(); return true; } >From 3aa2ba5f83ec50223d41bc7bede88d4719e3809c Mon Sep 17 00:00:00 2001 From: yronglin <[email protected]> Date: Mon, 22 Jun 2026 16:57:31 +0800 Subject: [PATCH 2/3] Add explicit flag for caching lex mode Signed-off-by: yronglin <[email protected]> --- clang/include/clang/Lex/Preprocessor.h | 16 +++++++++------- clang/lib/Lex/PPCaching.cpp | 4 +++- clang/lib/Lex/PPLexerChange.cpp | 6 +++++- clang/lib/Lex/Preprocessor.cpp | 6 ++++-- clang/lib/Parse/ParseStmt.cpp | 13 +++++++++---- 5 files changed, 30 insertions(+), 15 deletions(-) diff --git a/clang/include/clang/Lex/Preprocessor.h b/clang/include/clang/Lex/Preprocessor.h index 8b684e85eb1c1..4d47976ec536f 100644 --- a/clang/include/clang/Lex/Preprocessor.h +++ b/clang/include/clang/Lex/Preprocessor.h @@ -1190,6 +1190,9 @@ class Preprocessor { /// Lex() should be invoked. CachedTokensTy::size_type CachedLexPos = 0; + /// True when the caching lexer is installed as the active lexer layer. + bool IsCachingLexMode = false; + /// Stack of backtrack positions, allowing nested backtracks. /// /// The EnableBacktrackAtThisPos() method pushes a position to @@ -2583,7 +2586,7 @@ class Preprocessor { friend void TokenLexer::ExpandFunctionArguments(); void PushIncludeMacroStack() { - assert(CurLexerCallback != CLK_CachingLexer && + assert(!IsCachingLexMode && CurLexerCallback != CLK_CachingLexer && "cannot push a caching lexer"); IncludeMacroStack.emplace_back(CurLexerCallback, CurLexerSubmodule, std::move(CurLexer), CurPPLexer, @@ -2592,6 +2595,7 @@ class Preprocessor { } void PopIncludeMacroStack() { + IsCachingLexMode = false; if (CurLexer) PendingDestroyLexers.push_back(std::move(CurLexer)); CurLexer = std::move(IncludeMacroStack.back().TheLexer); @@ -2819,18 +2823,16 @@ class Preprocessor { // Caching stuff. void CachingLex(Token &Result); - bool InCachingLexMode() const { - // If the Lexer pointers are 0 and IncludeMacroStack is empty, it means - // that we are past EOF, not that we are in CachingLex mode. - return !CurPPLexer && !CurTokenLexer && !IncludeMacroStack.empty(); - } + bool InCachingLexMode() const { return IsCachingLexMode; } void EnterCachingLexMode(); void EnterCachingLexModeUnchecked(); void ExitCachingLexMode() { - if (InCachingLexMode()) + if (InCachingLexMode()) { + IsCachingLexMode = false; RemoveTopOfLexerStack(); + } } const Token &PeekAhead(unsigned N); diff --git a/clang/lib/Lex/PPCaching.cpp b/clang/lib/Lex/PPCaching.cpp index cbacda9d31ae2..d64183a35122a 100644 --- a/clang/lib/Lex/PPCaching.cpp +++ b/clang/lib/Lex/PPCaching.cpp @@ -126,8 +126,10 @@ void Preprocessor::EnterCachingLexMode() { } void Preprocessor::EnterCachingLexModeUnchecked() { - assert(CurLexerCallback != CLK_CachingLexer && "already in caching lex mode"); + assert(!InCachingLexMode() && CurLexerCallback != CLK_CachingLexer && + "already in caching lex mode"); PushIncludeMacroStack(); + IsCachingLexMode = true; CurLexerCallback = CLK_CachingLexer; } diff --git a/clang/lib/Lex/PPLexerChange.cpp b/clang/lib/Lex/PPLexerChange.cpp index 98ff9a9a04e7c..d901d02a44f7a 100644 --- a/clang/lib/Lex/PPLexerChange.cpp +++ b/clang/lib/Lex/PPLexerChange.cpp @@ -106,6 +106,9 @@ bool Preprocessor::EnterSourceFile(FileID FID, ConstSearchDirIterator CurDir, /// and start lexing tokens from it instead of the current buffer. void Preprocessor::EnterSourceFileWithLexer(std::unique_ptr<Lexer> TheLexer, ConstSearchDirIterator CurDir) { + if (InCachingLexMode()) + ExitCachingLexMode(); + PreprocessorLexer *PrevPPLexer = CurPPLexer; // Add the current lexer to the include stack. @@ -172,7 +175,8 @@ void Preprocessor::EnterMacro(Token &Tok, SourceLocation ILEnd, void Preprocessor::EnterTokenStream(const Token *Toks, unsigned NumToks, bool DisableMacroExpansion, bool OwnsTokens, bool IsReinject) { - if (CurLexerCallback == CLK_CachingLexer) { + if (InCachingLexMode()) { + assert(CurLexerCallback == CLK_CachingLexer && "Unexpected lexer kind"); if (CachedLexPos < CachedTokens.size()) { assert(IsReinject && "new tokens in the middle of cached stream"); // We're entering tokens into the middle of our cached token stream. We diff --git a/clang/lib/Lex/Preprocessor.cpp b/clang/lib/Lex/Preprocessor.cpp index 1e21b4a94cea3..c69d084d6514f 100644 --- a/clang/lib/Lex/Preprocessor.cpp +++ b/clang/lib/Lex/Preprocessor.cpp @@ -417,14 +417,16 @@ StringRef Preprocessor::getLastMacroWithSpelling( } void Preprocessor::recomputeCurLexerKind() { - if (CurLexer) + if (InCachingLexMode()) + CurLexerCallback = CLK_CachingLexer; + else if (CurLexer) CurLexerCallback = CurLexer->isDependencyDirectivesLexer() ? CLK_DependencyDirectivesLexer : CLK_Lexer; else if (CurTokenLexer) CurLexerCallback = CLK_TokenLexer; else - CurLexerCallback = CLK_CachingLexer; + CurLexerCallback = CLK_Lexer; } bool Preprocessor::SetCodeCompletionPoint(FileEntryRef File, diff --git a/clang/lib/Parse/ParseStmt.cpp b/clang/lib/Parse/ParseStmt.cpp index e77d6066847b2..e8dd987414249 100644 --- a/clang/lib/Parse/ParseStmt.cpp +++ b/clang/lib/Parse/ParseStmt.cpp @@ -2496,10 +2496,9 @@ bool Parser::trySkippingFunctionBody() { // We're in code-completion mode. Skip parsing for all function bodies unless // the body contains the code-completion point. - if (Tok.is(tok::kw_try)) - return false; TentativeParsingAction PA(*this); + bool IsTryCatch = Tok.is(tok::kw_try); CachedTokens Toks; bool ErrorInPrologue = ConsumeAndStoreFunctionPrologue(Toks); if (llvm::any_of(Toks, [](const Token &Tok) { @@ -2513,12 +2512,18 @@ bool Parser::trySkippingFunctionBody() { SkipMalformedDecl(); return true; } - if (!SkipUntil(tok::r_brace, StopAtCodeCompletion | StopBeforeMatch)) { + if (!SkipUntil(tok::r_brace, StopAtCodeCompletion)) { PA.Revert(); return false; } + while (IsTryCatch && Tok.is(tok::kw_catch)) { + if (!SkipUntil(tok::l_brace, StopAtCodeCompletion) || + !SkipUntil(tok::r_brace, StopAtCodeCompletion)) { + PA.Revert(); + return false; + } + } PA.Commit(); - ConsumeBrace(); return true; } >From 234dac06b8aa8d413f0a7379a096a95e39211011 Mon Sep 17 00:00:00 2001 From: Yihan Wang <[email protected]> Date: Mon, 22 Jun 2026 22:51:12 +0800 Subject: [PATCH 3/3] Revert blank changes. --- clang/lib/Parse/ParseStmt.cpp | 1 - 1 file changed, 1 deletion(-) diff --git a/clang/lib/Parse/ParseStmt.cpp b/clang/lib/Parse/ParseStmt.cpp index e8dd987414249..37f142e059930 100644 --- a/clang/lib/Parse/ParseStmt.cpp +++ b/clang/lib/Parse/ParseStmt.cpp @@ -2496,7 +2496,6 @@ bool Parser::trySkippingFunctionBody() { // We're in code-completion mode. Skip parsing for all function bodies unless // the body contains the code-completion point. - TentativeParsingAction PA(*this); bool IsTryCatch = Tok.is(tok::kw_try); CachedTokens Toks; _______________________________________________ cfe-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
