Author: Matheus Izvekov Date: 2021-07-28T23:28:45+02:00 New Revision: 87aa31827b293127619e2ef96e80baf709eae338
URL: https://github.com/llvm/llvm-project/commit/87aa31827b293127619e2ef96e80baf709eae338 DIFF: https://github.com/llvm/llvm-project/commit/87aa31827b293127619e2ef96e80baf709eae338.diff LOG: [clang] fix concepts crash on substitution failure during normalization When substitution failed on the first constrained template argument (but only the first), we would assert / crash. Checking for failure was only being performed from the second constraint on. This changes it so the checking is performed in that case, and the code is also now simplified a little bit to hopefully avoid this confusion. Signed-off-by: Matheus Izvekov <mizve...@gmail.com> Reviewed By: rsmith Differential Revision: https://reviews.llvm.org/D106907 Added: Modified: clang/lib/Sema/SemaConcept.cpp clang/test/CXX/temp/temp.constr/temp.constr.normal/p1.cpp Removed: ################################################################################ diff --git a/clang/lib/Sema/SemaConcept.cpp b/clang/lib/Sema/SemaConcept.cpp index 30f0730671c0a..82443be09c062 100644 --- a/clang/lib/Sema/SemaConcept.cpp +++ b/clang/lib/Sema/SemaConcept.cpp @@ -742,22 +742,15 @@ Optional<NormalizedConstraint> NormalizedConstraint::fromConstraintExprs(Sema &S, NamedDecl *D, ArrayRef<const Expr *> E) { assert(E.size() != 0); - auto First = fromConstraintExpr(S, D, E[0]); - if (E.size() == 1) - return First; - auto Second = fromConstraintExpr(S, D, E[1]); - if (!Second) + auto Conjunction = fromConstraintExpr(S, D, E[0]); + if (!Conjunction) return None; - llvm::Optional<NormalizedConstraint> Conjunction; - Conjunction.emplace(S.Context, std::move(*First), std::move(*Second), - CCK_Conjunction); - for (unsigned I = 2; I < E.size(); ++I) { + for (unsigned I = 1; I < E.size(); ++I) { auto Next = fromConstraintExpr(S, D, E[I]); if (!Next) - return llvm::Optional<NormalizedConstraint>{}; - NormalizedConstraint NewConjunction(S.Context, std::move(*Conjunction), + return None; + *Conjunction = NormalizedConstraint(S.Context, std::move(*Conjunction), std::move(*Next), CCK_Conjunction); - *Conjunction = std::move(NewConjunction); } return Conjunction; } diff --git a/clang/test/CXX/temp/temp.constr/temp.constr.normal/p1.cpp b/clang/test/CXX/temp/temp.constr/temp.constr.normal/p1.cpp index 153d4a56bea31..2134968101470 100644 --- a/clang/test/CXX/temp/temp.constr/temp.constr.normal/p1.cpp +++ b/clang/test/CXX/temp/temp.constr/temp.constr.normal/p1.cpp @@ -67,3 +67,18 @@ namespace non_type_pack { static_assert((foo<1>(), true)); } + +namespace PR47174 { +// This checks that we don't crash with a failed substitution on the first constrained argument when +// performing normalization. +template <Bar2 T, True U> +requires true struct S3; // expected-note {{template is declared here}} +template <True T, True U> +requires true struct S3<T, U>; // expected-error {{class template partial specialization is not more specialized than the primary template}} + +// Same as above, for the second position (but this was already working). +template <True T, Bar2 U> +requires true struct S4; // expected-note {{template is declared here}} +template <True T, True U> +requires true struct S4<T, U>; // expected-error {{class template partial specialization is not more specialized than the primary template}} +} // namespace PR47174 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits