diff options
Diffstat (limited to 'compiler/rustc_passes/src')
| -rw-r--r-- | compiler/rustc_passes/src/check_attr.rs | 21 | ||||
| -rw-r--r-- | compiler/rustc_passes/src/liveness.rs | 45 |
2 files changed, 42 insertions, 24 deletions
diff --git a/compiler/rustc_passes/src/check_attr.rs b/compiler/rustc_passes/src/check_attr.rs index d0723c68a77..20d03d797fe 100644 --- a/compiler/rustc_passes/src/check_attr.rs +++ b/compiler/rustc_passes/src/check_attr.rs @@ -1808,21 +1808,6 @@ impl CheckAttrVisitor<'_> { _ => ("a", "struct, enum, or union"), } } - sym::no_niche => { - if !self.tcx.features().enabled(sym::no_niche) { - feature_err( - &self.tcx.sess.parse_sess, - sym::no_niche, - hint.span(), - "the attribute `repr(no_niche)` is currently unstable", - ) - .emit(); - } - match target { - Target::Struct | Target::Enum => continue, - _ => ("a", "struct or enum"), - } - } sym::i8 | sym::u8 | sym::i16 @@ -1870,10 +1855,8 @@ impl CheckAttrVisitor<'_> { // This is not ideal, but tracking precisely which ones are at fault is a huge hassle. let hint_spans = hints.iter().map(|hint| hint.span()); - // Error on repr(transparent, <anything else apart from no_niche>). - let non_no_niche = |hint: &&NestedMetaItem| hint.name_or_empty() != sym::no_niche; - let non_no_niche_count = hints.iter().filter(non_no_niche).count(); - if is_transparent && non_no_niche_count > 1 { + // Error on repr(transparent, <anything else>). + if is_transparent && hints.len() > 1 { let hint_spans: Vec<_> = hint_spans.clone().collect(); struct_span_err!( self.tcx.sess, diff --git a/compiler/rustc_passes/src/liveness.rs b/compiler/rustc_passes/src/liveness.rs index 0070c0699a4..eed3e1579a2 100644 --- a/compiler/rustc_passes/src/liveness.rs +++ b/compiler/rustc_passes/src/liveness.rs @@ -278,7 +278,7 @@ impl<'tcx> IrMaps<'tcx> { pats.extend(inner_pat.iter()); } Struct(_, fields, _) => { - let (short, not_short): (Vec<&_>, Vec<&_>) = + let (short, not_short): (Vec<_>, _) = fields.iter().partition(|f| f.is_shorthand); shorthand_field_ids.extend(short.iter().map(|f| f.pat.hir_id)); pats.extend(not_short.iter().map(|f| f.pat)); @@ -298,7 +298,7 @@ impl<'tcx> IrMaps<'tcx> { } } - return shorthand_field_ids; + shorthand_field_ids } fn add_from_pat(&mut self, pat: &hir::Pat<'tcx>) { @@ -368,6 +368,9 @@ impl<'tcx> Visitor<'tcx> for IrMaps<'tcx> { fn visit_local(&mut self, local: &'tcx hir::Local<'tcx>) { self.add_from_pat(&local.pat); + if local.els.is_some() { + self.add_live_node_for_node(local.hir_id, ExprNode(local.span, local.hir_id)); + } intravisit::walk_local(self, local); } @@ -800,8 +803,40 @@ impl<'a, 'tcx> Liveness<'a, 'tcx> { // initialization, which is mildly more complex than checking // once at the func header but otherwise equivalent. - let succ = self.propagate_through_opt_expr(local.init, succ); - self.define_bindings_in_pat(&local.pat, succ) + if let Some(els) = local.els { + // Eventually, `let pat: ty = init else { els };` is mostly equivalent to + // `let (bindings, ...) = match init { pat => (bindings, ...), _ => els };` + // except that extended lifetime applies at the `init` location. + // + // (e) + // | + // v + // (expr) + // / \ + // | | + // v v + // bindings els + // | + // v + // ( succ ) + // + if let Some(init) = local.init { + let else_ln = self.propagate_through_block(els, succ); + let ln = self.live_node(local.hir_id, local.span); + self.init_from_succ(ln, succ); + self.merge_from_succ(ln, else_ln); + let succ = self.propagate_through_expr(init, ln); + self.define_bindings_in_pat(&local.pat, succ) + } else { + span_bug!( + stmt.span, + "variable is uninitialized but an unexpected else branch is found" + ) + } + } else { + let succ = self.propagate_through_opt_expr(local.init, succ); + self.define_bindings_in_pat(&local.pat, succ) + } } hir::StmtKind::Item(..) => succ, hir::StmtKind::Expr(ref expr) | hir::StmtKind::Semi(ref expr) => { @@ -1121,7 +1156,7 @@ impl<'a, 'tcx> Liveness<'a, 'tcx> { // (rvalue) || (rvalue) // | || | // v || v - // (write of place) || (place components) + // (write of place) || (place components) // | || | // v || v // (succ) || (succ) |