From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 1643) id 7CD1D385828E; Wed, 19 Oct 2022 19:45:33 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 7CD1D385828E DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1666208733; bh=xi7+XkSjz9xRVBdmq72FOq91SVgPNigAA89qsZ47afo=; h=From:To:Subject:Date:From; b=WPhc4gRsfK6tJGltNgOqkVQDLGfFLbZvvfIY3sOmmRr+224TNvVN8Rwhi3dWKOhbb ISReU78wcWq8oiHYzVuXCJXk8H8G1fgzLVmn1zCGvt010XX/KLIg9tEEW12bYqPa+p xlHOfKMEp9SR5qOVR3var9jxR2Ub3sXlq2mxtuwE= Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit From: Thomas Schwinge To: gcc-cvs@gcc.gnu.org Subject: [gcc/devel/rust/master] Add check for recursive trait cycles X-Act-Checkin: gcc X-Git-Author: Philip Herron X-Git-Refname: refs/heads/devel/rust/master X-Git-Oldrev: 381e061438836b7ca360c7741e9a13ec6d643b1d X-Git-Newrev: 0a52177612f6e855732c6ded77a04ba40dfb0d19 Message-Id: <20221019194533.7CD1D385828E@sourceware.org> Date: Wed, 19 Oct 2022 19:45:33 +0000 (GMT) List-Id: https://gcc.gnu.org/g:0a52177612f6e855732c6ded77a04ba40dfb0d19 commit 0a52177612f6e855732c6ded77a04ba40dfb0d19 Author: Philip Herron Date: Mon Oct 17 11:35:26 2022 +0100 Add check for recursive trait cycles This adds a new RAII style TraitQueryGuard so that we can manage the query lifetime when resolving a trait. This adds in a DefId into a set when we begin to resolve and then finally removes it when completed. This allows us to add in a check at the start if this DefId is already within the set which means this is a trait cycle. Fixes #1589 Diff: --- gcc/rust/typecheck/rust-hir-trait-resolve.cc | 12 +++++++++++- gcc/rust/typecheck/rust-hir-type-check.h | 29 ++++++++++++++++++++++++++++ gcc/testsuite/rust/compile/issue-1589.rs | 5 +++++ 3 files changed, 45 insertions(+), 1 deletion(-) diff --git a/gcc/rust/typecheck/rust-hir-trait-resolve.cc b/gcc/rust/typecheck/rust-hir-trait-resolve.cc index cc23fe22d7f..6bd3cc1a9e9 100644 --- a/gcc/rust/typecheck/rust-hir-trait-resolve.cc +++ b/gcc/rust/typecheck/rust-hir-trait-resolve.cc @@ -141,6 +141,14 @@ TraitResolver::resolve_trait (HIR::Trait *trait_reference) return tref; } + DefId trait_id = trait_reference->get_mappings ().get_defid (); + if (context->trait_query_in_progress (trait_id)) + { + rust_error_at (trait_reference->get_locus (), "trait cycle detected"); + return &TraitReference::error_node (); + } + + TraitQueryGuard guard (trait_id); TyTy::BaseType *self = nullptr; std::vector substitutions; for (auto &generic_param : trait_reference->get_generic_params ()) @@ -201,8 +209,10 @@ TraitResolver::resolve_trait (HIR::Trait *trait_reference) HIR::TraitBound *b = static_cast (bound.get ()); - // FIXME this might be recursive we need a check for that auto predicate = get_predicate_from_bound (b->get_path ()); + if (predicate.is_error ()) + return &TraitReference::error_node (); + specified_bounds.push_back (predicate); super_traits.push_back (predicate.get ()); } diff --git a/gcc/rust/typecheck/rust-hir-type-check.h b/gcc/rust/typecheck/rust-hir-type-check.h index f85585bccf6..de3467b27ce 100644 --- a/gcc/rust/typecheck/rust-hir-type-check.h +++ b/gcc/rust/typecheck/rust-hir-type-check.h @@ -381,6 +381,19 @@ public: return querys_in_progress.find (id) != querys_in_progress.end (); } + void insert_trait_query (DefId id) { trait_queries_in_progress.insert (id); } + + void trait_query_completed (DefId id) + { + trait_queries_in_progress.erase (id); + } + + bool trait_query_in_progress (DefId id) const + { + return trait_queries_in_progress.find (id) + != trait_queries_in_progress.end (); + } + private: TypeCheckContext (); @@ -418,6 +431,7 @@ private: // query context lookups std::set querys_in_progress; + std::set trait_queries_in_progress; }; class TypeResolution @@ -426,6 +440,21 @@ public: static void Resolve (HIR::Crate &crate); }; +class TraitQueryGuard +{ +public: + TraitQueryGuard (DefId id) : id (id), ctx (*TypeCheckContext::get ()) + { + ctx.insert_trait_query (id); + } + + ~TraitQueryGuard () { ctx.trait_query_completed (id); } + +private: + DefId id; + TypeCheckContext &ctx; +}; + } // namespace Resolver } // namespace Rust diff --git a/gcc/testsuite/rust/compile/issue-1589.rs b/gcc/testsuite/rust/compile/issue-1589.rs new file mode 100644 index 00000000000..79a5866e4af --- /dev/null +++ b/gcc/testsuite/rust/compile/issue-1589.rs @@ -0,0 +1,5 @@ +pub trait A: B {} +// { dg-error "trait cycle detected" "" { target *-*-* } .-1 } + +pub trait B: A {} +// { dg-error "trait cycle detected" "" { target *-*-* } .-1 }