https://github.com/anondeveg created https://github.com/llvm/llvm-project/pull/218571
Problem: when `-fdelayed-template-parsing` is enabled Instantiating a late-parsed function template defined in an earlier TU caused an assertion failure in `clang::Sema::PushDeclContext`: ``DC->getLexicalParent() == CurContext && "The next DeclContext should be lexically contained in the current one."'` Fix: - 1 in `Parser::ParseLateTemplatedFuncDef` obtained the enclosing `TranslationUnitDecl` called it `LexicalTU` - 2 changed `GlobalSavedContext` with the `LexicalTU` instead of using `Actions.Context.getTranslationUnitDecl()` - in the case that no `LexicalTU` was found fellback to `Actions.Context.getTranslationUnitDecl()` Fixes 217073 >From 5505763083dd71596b4965b273d2353e3bb5a160 Mon Sep 17 00:00:00 2001 From: Anondev <[email protected]> Date: Tue, 25 Aug 2026 04:11:48 +0300 Subject: [PATCH] [clang][Parse] Fix DeclContext reentry to use the template's lexical TU, not the current fragment's TU Fixes 217073 --- clang/lib/Parse/ParseTemplate.cpp | 20 ++++++++++++++------ 1 file changed, 14 insertions(+), 6 deletions(-) diff --git a/clang/lib/Parse/ParseTemplate.cpp b/clang/lib/Parse/ParseTemplate.cpp index 735a9bd1f9f1c..cba4a29888516 100644 --- a/clang/lib/Parse/ParseTemplate.cpp +++ b/clang/lib/Parse/ParseTemplate.cpp @@ -1451,17 +1451,25 @@ void Parser::ParseLateTemplatedFuncDef(LateParsedTemplate &LPT) { // Track template parameter depth. TemplateParameterDepthRAII CurTemplateDepthTracker(TemplateParameterDepth); - // To restore the context after late parsing. - Sema::ContextRAII GlobalSavedContext( - Actions, Actions.Context.getTranslationUnitDecl()); - MultiParseScope Scopes(*this); // Get the list of DeclContexts to reenter. SmallVector<DeclContext*, 4> DeclContextsToReenter; - for (DeclContext *DC = FunD; DC && !DC->isTranslationUnit(); - DC = DC->getLexicalParent()) + DeclContext *LexicalTU = nullptr; + for (DeclContext *DC = FunD; DC; DC = DC->getLexicalParent()) { + if (DC->isTranslationUnit()) { + LexicalTU = DC; + break; + } DeclContextsToReenter.push_back(DC); + } + + if (!LexicalTU) { + LexicalTU = Actions.Context.getTranslationUnitDecl(); + } + + // To restore the context after late parsing. + Sema::ContextRAII GlobalSavedContext(Actions, LexicalTU); // Reenter scopes from outermost to innermost. for (DeclContext *DC : reverse(DeclContextsToReenter)) { _______________________________________________ cfe-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
