llvmbot wrote:
<!--LLVM PR SUMMARY COMMENT--> @llvm/pr-subscribers-clang Author: Younan Zhang (zyn0217) <details> <summary>Changes</summary> This fixes the case shown by https://github.com/llvm/llvm-project/issues/64808#issuecomment-1929131611. Similar to https://github.com/llvm/llvm-project/commit/f9caa12328b265b77221fe7a310d4504673d814a, we have some calls to constraint checking for a lambda's conversion function while determining the conversion sequence. This patch addresses the problem where the requires-expression within such a lambda references to a Decl outside of the lambda by adding these Decls to the current instantiation scope. I'm abusing the flag `ForOverloadResolution` of CheckFunctionConstraints, which is actually meant to consider the Decls from parent DeclContexts. --- Full diff: https://github.com/llvm/llvm-project/pull/83420.diff 3 Files Affected: - (modified) clang/docs/ReleaseNotes.rst (+3) - (modified) clang/lib/Sema/SemaOverload.cpp (+2-1) - (modified) clang/test/SemaTemplate/concepts.cpp (+29) ``````````diff diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst index 7e16b9f0c67dbd..10f7e7129e97ac 100644 --- a/clang/docs/ReleaseNotes.rst +++ b/clang/docs/ReleaseNotes.rst @@ -290,6 +290,9 @@ Bug Fixes to C++ Support lookup searches the bases of an incomplete class. - Fix a crash when an unresolved overload set is encountered on the RHS of a ``.*`` operator. (`#53815 <https://github.com/llvm/llvm-project/issues/53815>`_) +- Fixed a crash while checking constraints of a trailing requires-expression of a lambda, that the + expression references to an entity declared outside of the lambda. This is a reduction from + (`#64808 <https://github.com/llvm/llvm-project/issues/64808>`_). Bug Fixes to AST Handling ^^^^^^^^^^^^^^^^^^^^^^^^^ diff --git a/clang/lib/Sema/SemaOverload.cpp b/clang/lib/Sema/SemaOverload.cpp index 7d38043890ca20..f6a2cfa60892f9 100644 --- a/clang/lib/Sema/SemaOverload.cpp +++ b/clang/lib/Sema/SemaOverload.cpp @@ -7976,7 +7976,8 @@ void Sema::AddConversionCandidate( if (Conversion->getTrailingRequiresClause()) { ConstraintSatisfaction Satisfaction; - if (CheckFunctionConstraints(Conversion, Satisfaction) || + if (CheckFunctionConstraints(Conversion, Satisfaction, /*UsageLoc=*/{}, + /*ShouldAddDeclsFromParentScope=*/true) || !Satisfaction.IsSatisfied) { Candidate.Viable = false; Candidate.FailureKind = ovl_fail_constraints_not_satisfied; diff --git a/clang/test/SemaTemplate/concepts.cpp b/clang/test/SemaTemplate/concepts.cpp index bac209a28da912..b7ea0d003a52d7 100644 --- a/clang/test/SemaTemplate/concepts.cpp +++ b/clang/test/SemaTemplate/concepts.cpp @@ -1085,3 +1085,32 @@ template void Struct<void>::bar<>(); template int Struct<void>::field<1, 2>; } + +namespace GH64808 { + +template <class T> struct basic_sender { + T func; + basic_sender(T) : func(T()) {} +}; + +auto a = basic_sender{[](auto... __captures) { + return []() // #note-a-1 + requires((__captures, ...), false) // #note-a-2 + {}; +}()}; + +auto b = basic_sender{[](auto... __captures) { + return []() + requires([](int, double) { return true; }(decltype(__captures)()...)) + {}; +}(1, 2.33)}; + +void foo() { + a.func(); + // expected-error@-1{{no matching function for call}} + // expected-note@#note-a-1{{constraints not satisfied}} + // expected-note@#note-a-2{{evaluated to false}} + b.func(); +} + +} // namespace GH64808 `````````` </details> https://github.com/llvm/llvm-project/pull/83420 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
