From e755e6e407be2ed3d6d3d93a215a9237c681026d Mon Sep 17 00:00:00 2001 From: Philip Herron Date: Mon, 17 Apr 2023 20:48:41 +0100 Subject: [PATCH] gccrs: Fix memory corruption at peek_context When working in the resolve_operator_overload it was found that we got memory corruption as method resolution will use the query system and therefore resolve new methods and the current function context info will change and due to the fact the peek_context interface returns a reference to the element which was now safe from a vector which can change and all you need is the current function context at that moment in time. gcc/rust/ChangeLog: * typecheck/rust-autoderef.cc: don't take a reference * typecheck/rust-hir-type-check-expr.cc (TypeCheckExpr::visit): likewise * typecheck/rust-hir-type-check.h: remove reference * typecheck/rust-typecheck-context.cc (TypeCheckContext::pop_return_type): likewise Signed-off-by: Philip Herron --- gcc/rust/typecheck/rust-autoderef.cc | 2 +- gcc/rust/typecheck/rust-hir-type-check-expr.cc | 4 ++-- gcc/rust/typecheck/rust-hir-type-check.h | 2 +- gcc/rust/typecheck/rust-typecheck-context.cc | 2 +- 4 files changed, 5 insertions(+), 5 deletions(-) diff --git a/gcc/rust/typecheck/rust-autoderef.cc b/gcc/rust/typecheck/rust-autoderef.cc index d4a21ce1a262..adaf575b2c15 100644 --- a/gcc/rust/typecheck/rust-autoderef.cc +++ b/gcc/rust/typecheck/rust-autoderef.cc @@ -164,7 +164,7 @@ resolve_operator_overload_fn ( // handle the case where we are within the impl block for this // lang_item otherwise we end up with a recursive operator overload // such as the i32 operator overload trait - TypeCheckContextItem &fn_context = context->peek_context (); + TypeCheckContextItem fn_context = context->peek_context (); if (fn_context.get_type () == TypeCheckContextItem::ItemType::IMPL_ITEM) { auto &impl_item = fn_context.get_impl_item (); diff --git a/gcc/rust/typecheck/rust-hir-type-check-expr.cc b/gcc/rust/typecheck/rust-hir-type-check-expr.cc index 6594068a1eba..ce215e35322e 100644 --- a/gcc/rust/typecheck/rust-hir-type-check-expr.cc +++ b/gcc/rust/typecheck/rust-hir-type-check-expr.cc @@ -1457,7 +1457,7 @@ TypeCheckExpr::visit (HIR::MatchExpr &expr) void TypeCheckExpr::visit (HIR::ClosureExpr &expr) { - TypeCheckContextItem ¤t_context = context->peek_context (); + TypeCheckContextItem current_context = context->peek_context (); TyTy::FnType *current_context_fndecl = current_context.get_context_type (); HirId ref = expr.get_mappings ().get_hirid (); @@ -1624,7 +1624,7 @@ TypeCheckExpr::resolve_operator_overload ( // handle the case where we are within the impl block for this lang_item // otherwise we end up with a recursive operator overload such as the i32 // operator overload trait - TypeCheckContextItem &fn_context = context->peek_context (); + TypeCheckContextItem fn_context = context->peek_context (); if (fn_context.get_type () == TypeCheckContextItem::ItemType::IMPL_ITEM) { auto &impl_item = fn_context.get_impl_item (); diff --git a/gcc/rust/typecheck/rust-hir-type-check.h b/gcc/rust/typecheck/rust-hir-type-check.h index 427c56be29f3..10aa3b32a9e0 100644 --- a/gcc/rust/typecheck/rust-hir-type-check.h +++ b/gcc/rust/typecheck/rust-hir-type-check.h @@ -90,7 +90,7 @@ public: bool lookup_type_by_node_id (NodeId ref, HirId *id); TyTy::BaseType *peek_return_type (); - TypeCheckContextItem &peek_context (); + TypeCheckContextItem peek_context (); void push_return_type (TypeCheckContextItem item, TyTy::BaseType *return_type); void pop_return_type (); diff --git a/gcc/rust/typecheck/rust-typecheck-context.cc b/gcc/rust/typecheck/rust-typecheck-context.cc index 7b2c96cdce28..dcf06098cc53 100644 --- a/gcc/rust/typecheck/rust-typecheck-context.cc +++ b/gcc/rust/typecheck/rust-typecheck-context.cc @@ -157,7 +157,7 @@ TypeCheckContext::pop_return_type () return_type_stack.pop_back (); } -TypeCheckContextItem & +TypeCheckContextItem TypeCheckContext::peek_context () { rust_assert (!return_type_stack.empty ()); -- 2.43.5