Merge rustc into rmc - 2021 week

Fixes rust-lang#716

Conflicts:
    .github/workflows/ci.yml
    src/tools/compiletest/src/runtest.rs

Author: celinval

.mailmap

@@ -289,12 +289,14 @@ Tim Joseph Dumol <[email protected]>
 Torsten Weber <[email protected]> <[email protected]>
 Trevor Spiteri <[email protected]> <[email protected]>
 Ty Overby <[email protected]>
+Tyler Mandry <[email protected]> <[email protected]>
 Ulrik Sverdrup <[email protected]> bluss <[email protected]>
 Ulrik Sverdrup <[email protected]> bluss <bluss>
 Ulrik Sverdrup <[email protected]> Ulrik Sverdrup <root@localhost>
 Vadim Petrochenkov <[email protected]>
 Vadim Petrochenkov <[email protected]> petrochenkov <[email protected]>
 Vitali Haravy <[email protected]> Vitali Haravy <[email protected]>
+Wesley Wiser <[email protected]> <[email protected]>
 whitequark <[email protected]>
 William Ting <[email protected]> <[email protected]>
 Xuefeng Wu <[email protected]> Xuefeng Wu <[email protected]>

Cargo.lock

@@ -297,7 +297,7 @@ dependencies = [
 
 [[package]]
 name = "cargo"
-version = "0.59.0"
+version = "0.60.0"
 dependencies = [
  "anyhow",
  "atty",
@@ -440,7 +440,7 @@ dependencies = [
 
 [[package]]
 name = "cargo-util"
-version = "0.1.1"
+version = "0.1.2"
 dependencies = [
  "anyhow",
  "core-foundation",
@@ -549,9 +549,9 @@ checksum = "baf1de4339761588bc0619e3cbc0120ee582ebb74b53b4efbf79117bd2da40fd"
 
 [[package]]
 name = "chalk-derive"
-version = "0.55.0"
+version = "0.75.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3983193cacd81f0f924acb666b7fe5e1a0d81db9f113fa69203eda7ea8ce8b6c"
+checksum = "d54e3b5f9e3425e6b119ff07568d8d006bfa5a8d6f78a9cbc3530b1e962e316c"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -561,9 +561,9 @@ dependencies = [
 
 [[package]]
 name = "chalk-engine"
-version = "0.55.0"
+version = "0.75.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "05a171ce5abbf0fbd06f221ab80ab182c7ef78603d23b858bc44e7ce8a86a396"
+checksum = "bdc891073396b167163db77123b0a3c00088edc00466cecc5531f33e3e989523"
 dependencies = [
  "chalk-derive",
  "chalk-ir",
@@ -574,9 +574,9 @@ dependencies = [
 
 [[package]]
 name = "chalk-ir"
-version = "0.55.0"
+version = "0.75.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a522f53af971e7678f472d687e053120157b3ae26e2ebd5ecbc0f5ab124f2cb6"
+checksum = "2b79e5a1d04b79311e90c69356a2c62027853906a7e33b3e070b93c055fc3e8a"
 dependencies = [
  "bitflags",
  "chalk-derive",
@@ -585,14 +585,14 @@ dependencies = [
 
 [[package]]
 name = "chalk-solve"
-version = "0.55.0"
+version = "0.75.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "cdf79fb77a567e456a170f7ec84ea6584163d4ba3f13660cd182013d34ca667c"
+checksum = "a5d2a1db6605aba70a58820bd80ac422b218913a510f1a40beef9efc5371ea1d"
 dependencies = [
  "chalk-derive",
  "chalk-ir",
  "ena",
- "itertools 0.9.0",
+ "itertools 0.10.1",
  "petgraph",
  "rustc-hash",
  "tracing",
@@ -737,9 +737,9 @@ dependencies = [
 
 [[package]]
 name = "compiler_builtins"
-version = "0.1.55"
+version = "0.1.66"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c9ac60765140c97aaf531dae151a287646b0805ec725805da9e2a3ee31cd501c"
+checksum = "191424db7756bbed2c4996959a0fbda94388abcf4f5a2728a8af17481ad9c4f7"
 dependencies = [
  "cc",
  "rustc-std-workspace-core",
@@ -836,7 +836,7 @@ checksum = "8aebca1129a03dc6dc2b127edd729435bbc4a37e1d5f4d7513165089ceb02634"
 
 [[package]]
 name = "crates-io"
-version = "0.33.0"
+version = "0.33.1"
 dependencies = [
  "anyhow",
  "curl",
@@ -2189,9 +2189,9 @@ dependencies = [
 
 [[package]]
 name = "matchers"
-version = "0.0.1"
+version = "0.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f099785f7595cc4b4553a174ce30dd7589ef93391ff414dbb67f62392b9e0ce1"
+checksum = "8263075bb86c5a1b1427b5ae862e8889656f126e9f77c484496e8b47cf5c5558"
 dependencies = [
  "regex-automata",
 ]
@@ -3857,6 +3857,7 @@ dependencies = [
  "rustc_expand",
  "rustc_feature",
  "rustc_lexer",
+ "rustc_lint_defs",
  "rustc_parse",
  "rustc_parse_format",
  "rustc_session",
@@ -5346,9 +5347,9 @@ dependencies = [
 
 [[package]]
 name = "synstructure"
-version = "0.12.4"
+version = "0.12.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b834f2d66f734cb897113e34aaff2f1ab4719ca946f9a7358dba8f8064148701"
+checksum = "f36bdaa60a83aca3921b5259d5400cbf5e90fc51931376a9bd4a0eb79aa7210f"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -5671,49 +5672,34 @@ dependencies = [
  "tracing-core",
 ]
 
-[[package]]
-name = "tracing-serde"
-version = "0.1.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "fb65ea441fbb84f9f6748fd496cf7f63ec9af5bca94dd86456978d055e8eb28b"
-dependencies = [
- "serde",
- "tracing-core",
-]
-
 [[package]]
 name = "tracing-subscriber"
-version = "0.2.16"
+version = "0.3.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8ab8966ac3ca27126141f7999361cc97dd6fb4b71da04c02044fa9045d98bb96"
+checksum = "245da694cc7fc4729f3f418b304cb57789f1bed2a78c575407ab8a23f53cb4d3"
 dependencies = [
  "ansi_term 0.12.1",
- "chrono",
  "lazy_static",
  "matchers",
  "parking_lot",
  "regex",
- "serde",
- "serde_json",
  "sharded-slab",
  "smallvec",
  "thread_local",
  "tracing",
  "tracing-core",
  "tracing-log",
- "tracing-serde",
 ]
 
 [[package]]
 name = "tracing-tree"
-version = "0.1.9"
+version = "0.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1712b40907f8d9bc2bc66763ab61dec914b7123d7149e59feb0d4e2a95fc4967"
+checksum = "3ce989c9962c7f61fe084dd4a230eec784649dfc2392467c790007c3a6e134e7"
 dependencies = [
  "ansi_term 0.12.1",
  "atty",
- "termcolor",
- "tracing",
+ "tracing-core",
  "tracing-log",
  "tracing-subscriber",
 ]

compiler/rustc/src/main.rs

@@ -1,25 +1,32 @@
-// Configure jemalloc as the `global_allocator` when configured. This is
-// so that we use the sized deallocation apis jemalloc provides
-// (namely `sdallocx`).
+// A note about jemalloc: rustc uses jemalloc when built for CI and
+// distribution. The obvious way to do this is with the `#[global_allocator]`
+// mechanism. However, for complicated reasons (see
+// https://github.com/rust-lang/rust/pull/81782#issuecomment-784438001 for some
+// details) that mechanism doesn't work here. Also, we must use a consistent
+// allocator across the rustc <-> llvm boundary, and `#[global_allocator]`
+// wouldn't provide that.
 //
-// The symbol overrides documented below are also performed so that we can
-// ensure that we use a consistent allocator across the rustc <-> llvm boundary
-#[cfg(feature = "jemalloc")]
-#[global_allocator]
-static ALLOC: tikv_jemallocator::Jemalloc = tikv_jemallocator::Jemalloc;
-
+// Instead, we use a lower-level mechanism. rustc is linked with jemalloc in a
+// way such that jemalloc's implementation of `malloc`, `free`, etc., override
+// the libc allocator's implementation. This means that Rust's `System`
+// allocator, which calls `libc::malloc()` et al., is actually calling into
+// jemalloc.
+//
+// A consequence of not using `GlobalAlloc` (and the `tikv-jemallocator` crate
+// provides an impl of that trait, which is called `Jemalloc`) is that we
+// cannot use the sized deallocation APIs (`sdallocx`) that jemalloc provides.
+// It's unclear how much performance is lost because of this.
+//
+// As for the symbol overrides in `main` below: we're pulling in a static copy
+// of jemalloc. We need to actually reference its symbols for it to get linked.
+// The two crates we link to here, `std` and `rustc_driver`, are both dynamic
+// libraries. So we must reference jemalloc symbols one way or another, because
+// this file is the only object code in the rustc executable.
 #[cfg(feature = "tikv-jemalloc-sys")]
 use tikv_jemalloc_sys as jemalloc_sys;
 
 fn main() {
-    // Pull in jemalloc when enabled.
-    //
-    // Note that we're pulling in a static copy of jemalloc which means that to
-    // pull it in we need to actually reference its symbols for it to get
-    // linked. The two crates we link to here, std and rustc_driver, are both
-    // dynamic libraries. That means to pull in jemalloc we actually need to
-    // reference allocation symbols one way or another (as this file is the only
-    // object code in the rustc executable).
+    // See the comment at the top of this file for an explanation of this.
     #[cfg(feature = "tikv-jemalloc-sys")]
     {
         use std::os::raw::{c_int, c_void};

compiler/rustc_apfloat/src/lib.rs

@@ -33,7 +33,6 @@
 #![doc(html_root_url = "https://doc.rust-lang.org/nightly/nightly-rustc/")]
 #![no_std]
 #![forbid(unsafe_code)]
-#![feature(iter_zip)]
 #![feature(nll)]
 
 #[macro_use]

compiler/rustc_ast/src/lib.rs

@@ -11,7 +11,6 @@
 #![feature(box_patterns)]
 #![feature(crate_visibility_modifier)]
 #![feature(if_let_guard)]
-#![feature(iter_zip)]
 #![feature(label_break_value)]
 #![feature(nll)]
 #![feature(min_specialization)]

compiler/rustc_ast/src/mut_visit.rs

@@ -1,5 +1,5 @@
 //! A `MutVisitor` represents an AST modification; it accepts an AST piece and
-//! and mutates it in place. So, for instance, macro expansion is a `MutVisitor`
+//! mutates it in place. So, for instance, macro expansion is a `MutVisitor`
 //! that walks over an AST and modifies it.
 //!
 //! Note: using a `MutVisitor` (other than the `MacroExpander` `MutVisitor`) on

compiler/rustc_ast/src/util/literal.rs

@@ -35,12 +35,12 @@ impl LitKind {
                 LitKind::Bool(symbol == kw::True)
             }
             token::Byte => {
-                return unescape_byte(&symbol.as_str())
+                return unescape_byte(symbol.as_str())
                     .map(LitKind::Byte)
                     .map_err(|_| LitError::LexerError);
             }
             token::Char => {
-                return unescape_char(&symbol.as_str())
+                return unescape_char(symbol.as_str())
                     .map(LitKind::Char)
                     .map_err(|_| LitError::LexerError);
             }

compiler/rustc_ast_lowering/src/block.rs

@@ -2,7 +2,6 @@ use crate::{ImplTraitContext, ImplTraitPosition, LoweringContext};
 use rustc_ast::{AttrVec, Block, BlockCheckMode, Expr, Local, LocalKind, Stmt, StmtKind};
 use rustc_hir as hir;
 use rustc_session::parse::feature_err;
-use rustc_span::symbol::Ident;
 use rustc_span::{sym, DesugaringKind};
 
 use smallvec::SmallVec;
@@ -39,8 +38,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
                     let hir_id = self.lower_node_id(s.id);
                     match &local.kind {
                         LocalKind::InitElse(init, els) => {
-                            let (s, e) = self.lower_let_else(hir_id, local, init, els, tail);
-                            stmts.push(s);
+                            let e = self.lower_let_else(hir_id, local, init, els, tail);
                             expr = Some(e);
                             // remaining statements are in let-else expression
                             break;
@@ -125,36 +123,25 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
         init: &Expr,
         els: &Block,
         tail: &[Stmt],
-    ) -> (hir::Stmt<'hir>, &'hir hir::Expr<'hir>) {
+    ) -> &'hir hir::Expr<'hir> {
         let ty = local
             .ty
             .as_ref()
             .map(|t| self.lower_ty(t, ImplTraitContext::Disallowed(ImplTraitPosition::Binding)));
         let span = self.lower_span(local.span);
         let span = self.mark_span_with_reason(DesugaringKind::LetElse, span, None);
-        let init = Some(self.lower_expr(init));
-        let val = Ident::with_dummy_span(sym::val);
-        let (pat, val_id) =
-            self.pat_ident_binding_mode(span, val, hir::BindingAnnotation::Unannotated);
+        let init = self.lower_expr(init);
         let local_hir_id = self.lower_node_id(local.id);
         self.lower_attrs(local_hir_id, &local.attrs);
-        // first statement which basically exists for the type annotation
-        let stmt = {
-            let local = self.arena.alloc(hir::Local {
+        let let_expr = {
+            let lex = self.arena.alloc(hir::Let {
                 hir_id: local_hir_id,
+                pat: self.lower_pat(&local.pat),
                 ty,
-                pat,
                 init,
                 span,
-                source: hir::LocalSource::Normal,
             });
-            let kind = hir::StmtKind::Local(local);
-            hir::Stmt { hir_id: stmt_hir_id, kind, span }
-        };
-        let let_expr = {
-            let scrutinee = self.expr_ident(span, val, val_id);
-            let let_kind = hir::ExprKind::Let(self.lower_pat(&local.pat), scrutinee, span);
-            self.arena.alloc(self.expr(span, let_kind, AttrVec::new()))
+            self.arena.alloc(self.expr(span, hir::ExprKind::Let(lex), AttrVec::new()))
         };
         let then_expr = {
             let (stmts, expr) = self.lower_stmts(tail);
@@ -165,9 +152,10 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
             let block = self.lower_block(els, false);
             self.arena.alloc(self.expr_block(block, AttrVec::new()))
         };
+        self.alias_attrs(let_expr.hir_id, local_hir_id);
         self.alias_attrs(else_expr.hir_id, local_hir_id);
         let if_expr = self.arena.alloc(hir::Expr {
-            hir_id: self.next_id(),
+            hir_id: stmt_hir_id,
             span,
             kind: hir::ExprKind::If(let_expr, then_expr, Some(else_expr)),
         });
@@ -180,6 +168,6 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
             )
             .emit();
         }
-        (stmt, if_expr)
+        if_expr
     }
 }