https://github.com/ANAMASGARD created https://github.com/llvm/llvm-project/pull/213556
Closes #213420. This fixes a crash with `-fms-compatibility` when Clang late-parses an invalid default argument in a member function of a lambda-local anonymous struct. `getPredefinedExprDecl` assumed an active `LambdaScopeInfo` was always present. During delayed parsing, that scope may already have been popped. Handle that case and continue producing the normal diagnostics. Tests: - `llvm-lit -sv clang/test/SemaCXX/GH213420.cpp` - `llvm-lit -sv clang/test/SemaCXX` (no unexpected failures) - Manual assertion-enabled reproducer: no crash; emits the expected semantic errors - `git diff --check` AI assistance was used to investigate, implement, and test this change. I reviewed the resulting patch and test coverage. >From 48655deecf771b2248b73a008e293beaae1478ce Mon Sep 17 00:00:00 2001 From: Gaurav Chaudhary <[email protected]> Date: Sun, 2 Aug 2026 22:26:23 +0530 Subject: [PATCH] [clang] Fix crash during delayed default argument parsing Signed-off-by: Gaurav Chaudhary <[email protected]> --- clang/lib/Sema/SemaExpr.cpp | 7 +++++-- clang/test/SemaCXX/GH213420.cpp | 12 ++++++++++++ 2 files changed, 17 insertions(+), 2 deletions(-) create mode 100644 clang/test/SemaCXX/GH213420.cpp diff --git a/clang/lib/Sema/SemaExpr.cpp b/clang/lib/Sema/SemaExpr.cpp index 59b8c9b60663c..146dd7e78a27c 100644 --- a/clang/lib/Sema/SemaExpr.cpp +++ b/clang/lib/Sema/SemaExpr.cpp @@ -2125,8 +2125,11 @@ static Decl *getPredefinedExprDecl(Sema &S, DeclContext *DC) { while (LSI != E && isa<CapturingScopeInfo>(*LSI) && !isa<LambdaScopeInfo>(*LSI)) ++LSI; - assert(LSI != E && "Should be in a lambda scope info"); - if (dyn_cast<LambdaScopeInfo>(*LSI)->BeforeCompoundStatement) + if (LSI == E || !isa<LambdaScopeInfo>(*LSI)) { + // The lambda scope may already be popped during delayed parsing. + return; + } + if (cast<LambdaScopeInfo>(*LSI)->BeforeCompoundStatement) DC = DC->getParent(); ++LSI; } diff --git a/clang/test/SemaCXX/GH213420.cpp b/clang/test/SemaCXX/GH213420.cpp new file mode 100644 index 0000000000000..2d1b9f032e7e4 --- /dev/null +++ b/clang/test/SemaCXX/GH213420.cpp @@ -0,0 +1,12 @@ +// RUN: %clang_cc1 -std=c++11 -fsyntax-only -fms-compatibility -verify \ +// RUN: -Wno-missing-declarations -Wno-unused-value %s + +void foo() { + [] { + struct { // expected-error {{anonymous structs and classes must be class members}} + void bar(int & = "") {} // expected-error {{non-const lvalue reference to type 'int' cannot bind}} + // expected-note@-1 {{passing argument to parameter here}} + // expected-error@-2 {{functions cannot be declared in an anonymous struct}} + }; + }; +} _______________________________________________ cfe-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
