use rustc_hir::intravisit;
-use rustc_hir::{self, Body, FnDecl, HirId, HirIdSet, ItemKind, Impl, Node};
+use rustc_hir::{self, AssocItemKind, Body, FnDecl, HirId, HirIdSet, Impl, ItemKind, Node};
use rustc_infer::infer::TyCtxtInferExt;
use rustc_lint::{LateContext, LateLintPass};
-use rustc_middle::ty::{self, Ty};
+use rustc_middle::mir::FakeReadCause;
+use rustc_middle::ty::{self, TraitRef, Ty};
use rustc_session::{declare_tool_lint, impl_lint_pass};
use rustc_span::source_map::Span;
+use rustc_span::symbol::kw;
use rustc_target::abi::LayoutOf;
use rustc_target::spec::abi::Abi;
use rustc_typeck::expr_use_visitor::{ConsumeMode, Delegate, ExprUseVisitor, PlaceBase, PlaceWithHirId};
-use crate::utils::span_lint;
+use crate::utils::{contains_ty, span_lint};
#[derive(Copy, Clone)]
pub struct BoxedLocal {
struct EscapeDelegate<'a, 'tcx> {
cx: &'a LateContext<'tcx>,
set: HirIdSet,
+ trait_self_ty: Option<Ty<'a>>,
too_large_for_stack: u64,
}
}
}
- // If the method is an impl for a trait, don't warn.
let parent_id = cx.tcx.hir().get_parent_item(hir_id);
let parent_node = cx.tcx.hir().find(parent_id);
+ let mut trait_self_ty = None;
if let Some(Node::Item(item)) = parent_node {
+ // If the method is an impl for a trait, don't warn.
if let ItemKind::Impl(Impl { of_trait: Some(_), .. }) = item.kind {
return;
}
+
+ // find `self` ty for this trait if relevant
+ if let ItemKind::Trait(_, _, _, _, items) = item.kind {
+ for trait_item in items {
+ if trait_item.id.hir_id() == hir_id {
+ // be sure we have `self` parameter in this function
+ if let AssocItemKind::Fn { has_self: true } = trait_item.kind {
+ trait_self_ty =
+ Some(TraitRef::identity(cx.tcx, trait_item.id.def_id.to_def_id()).self_ty());
+ }
+ }
+ }
+ }
}
let mut v = EscapeDelegate {
cx,
set: HirIdSet::default(),
+ trait_self_ty,
too_large_for_stack: self.too_large_for_stack,
};
return;
}
+ // skip if there is a `self` parameter binding to a type
+ // that contains `Self` (i.e.: `self: Box<Self>`), see #4804
+ if let Some(trait_self_ty) = self.trait_self_ty {
+ if map.name(cmt.hir_id) == kw::SelfLower && contains_ty(cmt.place.ty(), trait_self_ty) {
+ return;
+ }
+ }
+
if is_non_trait_box(cmt.place.ty()) && !self.is_large_box(cmt.place.ty()) {
self.set.insert(cmt.hir_id);
}
- return;
}
}
}
+
+ fn fake_read(&mut self, _: rustc_typeck::expr_use_visitor::Place<'tcx>, _: FakeReadCause, _: HirId) { }
}
impl<'a, 'tcx> EscapeDelegate<'a, 'tcx> {