Rollup of 10 pull requests

.github/workflows/ci.yml

@@ -56,7 +56,7 @@ jobs:
       - name: disable git crlf conversion
         run: git config --global core.autocrlf false
       - name: checkout the source code
-        uses: actions/checkout@v2
+        uses: actions/checkout@v3
         with:
           fetch-depth: 2
       - name: configure the PR in which the error message will be posted
@@ -454,7 +454,7 @@ jobs:
       - name: disable git crlf conversion
         run: git config --global core.autocrlf false
       - name: checkout the source code
-        uses: actions/checkout@v2
+        uses: actions/checkout@v3
         with:
           fetch-depth: 2
       - name: configure the PR in which the error message will be posted
@@ -567,7 +567,7 @@ jobs:
       - name: disable git crlf conversion
         run: git config --global core.autocrlf false
       - name: checkout the source code
-        uses: actions/checkout@v2
+        uses: actions/checkout@v3
         with:
           fetch-depth: 2
       - name: configure the PR in which the error message will be posted
@@ -670,7 +670,7 @@ jobs:
     if: "github.event_name == 'push' && github.ref == 'refs/heads/master' && github.repository == 'rust-lang-ci/rust'"
     steps:
       - name: checkout the source code
-        uses: actions/checkout@v2
+        uses: actions/checkout@v3
         with:
           fetch-depth: 2
       - name: publish toolstate

compiler/rustc_ast_passes/src/feature_gate.rs

@@ -58,9 +58,22 @@ struct PostExpansionVisitor<'a> {
 }
 
 impl<'a> PostExpansionVisitor<'a> {
-    fn check_abi(&self, abi: ast::StrLit) {
+    fn check_abi(&self, abi: ast::StrLit, constness: ast::Const) {
         let ast::StrLit { symbol_unescaped, span, .. } = abi;
 
+        if let ast::Const::Yes(_) = constness {
+            match symbol_unescaped.as_str() {
+                // Stable
+                "Rust" | "C" => {}
+                abi => gate_feature_post!(
+                    &self,
+                    const_extern_fn,
+                    span,
+                    &format!("`{}` as a `const fn` ABI is unstable", abi)
+                ),
+            }
+        }
+
         match symbol_unescaped.as_str() {
             // Stable
             "Rust" | "C" | "cdecl" | "stdcall" | "fastcall" | "aapcs" | "win64" | "sysv64"
@@ -261,9 +274,9 @@ impl<'a> PostExpansionVisitor<'a> {
         }
     }
 
-    fn check_extern(&self, ext: ast::Extern) {
+    fn check_extern(&self, ext: ast::Extern, constness: ast::Const) {
         if let ast::Extern::Explicit(abi) = ext {
-            self.check_abi(abi);
+            self.check_abi(abi, constness);
         }
     }
 
@@ -437,7 +450,7 @@ impl<'a> Visitor<'a> for PostExpansionVisitor<'a> {
         match i.kind {
             ast::ItemKind::ForeignMod(ref foreign_module) => {
                 if let Some(abi) = foreign_module.abi {
-                    self.check_abi(abi);
+                    self.check_abi(abi, ast::Const::No);
                 }
             }
 
@@ -560,7 +573,8 @@ impl<'a> Visitor<'a> for PostExpansionVisitor<'a> {
     fn visit_ty(&mut self, ty: &'a ast::Ty) {
         match ty.kind {
             ast::TyKind::BareFn(ref bare_fn_ty) => {
-                self.check_extern(bare_fn_ty.ext);
+                // Function pointers cannot be `const`
+                self.check_extern(bare_fn_ty.ext, ast::Const::No);
             }
             ast::TyKind::Never => {
                 gate_feature_post!(&self, never_type, ty.span, "the `!` type is experimental");
@@ -660,18 +674,7 @@ impl<'a> Visitor<'a> for PostExpansionVisitor<'a> {
     fn visit_fn(&mut self, fn_kind: FnKind<'a>, span: Span, _: NodeId) {
         if let Some(header) = fn_kind.header() {
             // Stability of const fn methods are covered in `visit_assoc_item` below.
-            self.check_extern(header.ext);
-
-            if let (ast::Const::Yes(_), ast::Extern::Implicit)
-            | (ast::Const::Yes(_), ast::Extern::Explicit(_)) = (header.constness, header.ext)
-            {
-                gate_feature_post!(
-                    &self,
-                    const_extern_fn,
-                    span,
-                    "`const extern fn` definitions are unstable"
-                );
-            }
+            self.check_extern(header.ext, header.constness);
         }
 
         if fn_kind.ctxt() != Some(FnCtxt::Foreign) && fn_kind.decl().c_variadic() {

compiler/rustc_ast_pretty/src/pprust/state.rs

@@ -959,7 +959,7 @@ impl<'a> State<'a> {
                 self.word_space("=");
                 match term {
                     Term::Ty(ty) => self.print_type(ty),
-                    Term::Const(c) => self.print_expr_anon_const(c),
+                    Term::Const(c) => self.print_expr_anon_const(c, &[]),
                 }
             }
             ast::AssocConstraintKind::Bound { bounds } => self.print_type_bounds(":", &*bounds),

compiler/rustc_ast_pretty/src/pprust/state/expr.rs

@@ -88,10 +88,21 @@ impl<'a> State<'a> {
         self.end();
     }
 
-    pub(super) fn print_expr_anon_const(&mut self, expr: &ast::AnonConst) {
+    pub(super) fn print_expr_anon_const(
+        &mut self,
+        expr: &ast::AnonConst,
+        attrs: &[ast::Attribute],
+    ) {
         self.ibox(INDENT_UNIT);
         self.word("const");
-        self.print_expr(&expr.value);
+        self.nbsp();
+        if let ast::ExprKind::Block(block, None) = &expr.value.kind {
+            self.cbox(0);
+            self.ibox(0);
+            self.print_block_with_attrs(block, attrs);
+        } else {
+            self.print_expr(&expr.value);
+        }
         self.end();
     }
 
@@ -275,7 +286,7 @@ impl<'a> State<'a> {
                 self.print_expr_vec(exprs);
             }
             ast::ExprKind::ConstBlock(ref anon_const) => {
-                self.print_expr_anon_const(anon_const);
+                self.print_expr_anon_const(anon_const, attrs);
             }
             ast::ExprKind::Repeat(ref element, ref count) => {
                 self.print_expr_repeat(element, count);

compiler/rustc_codegen_llvm/src/back/lto.rs

@@ -325,20 +325,6 @@ fn fat_lto(
         drop(linker);
         save_temp_bitcode(cgcx, &module, "lto.input");
 
-        // Fat LTO also suffers from the invalid DWARF issue similar to Thin LTO.
-        // Here we rewrite all `DICompileUnit` pointers if there is only one `DICompileUnit`.
-        // This only works around the problem when codegen-units = 1.
-        // Refer to the comments in the `optimize_thin_module` function for more details.
-        let mut cu1 = ptr::null_mut();
-        let mut cu2 = ptr::null_mut();
-        unsafe { llvm::LLVMRustLTOGetDICompileUnit(llmod, &mut cu1, &mut cu2) };
-        if !cu2.is_null() {
-            let _timer =
-                cgcx.prof.generic_activity_with_arg("LLVM_fat_lto_patch_debuginfo", &*module.name);
-            unsafe { llvm::LLVMRustLTOPatchDICompileUnit(llmod, cu1) };
-            save_temp_bitcode(cgcx, &module, "fat-lto-after-patch");
-        }
-
         // Internalize everything below threshold to help strip out more modules and such.
         unsafe {
             let ptr = symbols_below_threshold.as_ptr();
@@ -757,7 +743,7 @@ pub unsafe fn optimize_thin_module(
         // an error.
         let mut cu1 = ptr::null_mut();
         let mut cu2 = ptr::null_mut();
-        llvm::LLVMRustLTOGetDICompileUnit(llmod, &mut cu1, &mut cu2);
+        llvm::LLVMRustThinLTOGetDICompileUnit(llmod, &mut cu1, &mut cu2);
         if !cu2.is_null() {
             let msg = "multiple source DICompileUnits found";
             return Err(write::llvm_err(&diag_handler, msg));
@@ -846,7 +832,7 @@ pub unsafe fn optimize_thin_module(
             let _timer = cgcx
                 .prof
                 .generic_activity_with_arg("LLVM_thin_lto_patch_debuginfo", thin_module.name());
-            llvm::LLVMRustLTOPatchDICompileUnit(llmod, cu1);
+            llvm::LLVMRustThinLTOPatchDICompileUnit(llmod, cu1);
             save_temp_bitcode(cgcx, &module, "thin-lto-after-patch");
         }
 

compiler/rustc_codegen_llvm/src/intrinsic.rs

@@ -1839,6 +1839,27 @@ unsupported {} from `{}` with element `{}` of size `{}` to `{}`"#,
         simd_neg: Int => neg, Float => fneg;
     }
 
+    if name == sym::simd_arith_offset {
+        // This also checks that the first operand is a ptr type.
+        let pointee = in_elem.builtin_deref(true).unwrap_or_else(|| {
+            span_bug!(span, "must be called with a vector of pointer types as first argument")
+        });
+        let layout = bx.layout_of(pointee.ty);
+        let ptrs = args[0].immediate();
+        // The second argument must be a ptr-sized integer.
+        // (We don't care about the signedness, this is wrapping anyway.)
+        let (_offsets_len, offsets_elem) = arg_tys[1].simd_size_and_type(bx.tcx());
+        if !matches!(offsets_elem.kind(), ty::Int(ty::IntTy::Isize) | ty::Uint(ty::UintTy::Usize)) {
+            span_bug!(
+                span,
+                "must be called with a vector of pointer-sized integers as second argument"
+            );
+        }
+        let offsets = args[1].immediate();
+
+        return Ok(bx.gep(bx.backend_type(layout), ptrs, &[offsets]));
+    }
+
     if name == sym::simd_saturating_add || name == sym::simd_saturating_sub {
         let lhs = args[0].immediate();
         let rhs = args[1].immediate();

compiler/rustc_codegen_llvm/src/llvm/ffi.rs

@@ -2506,8 +2506,12 @@ extern "C" {
         len: usize,
         out_len: &mut usize,
     ) -> *const u8;
-    pub fn LLVMRustLTOGetDICompileUnit(M: &Module, CU1: &mut *mut c_void, CU2: &mut *mut c_void);
-    pub fn LLVMRustLTOPatchDICompileUnit(M: &Module, CU: *mut c_void);
+    pub fn LLVMRustThinLTOGetDICompileUnit(
+        M: &Module,
+        CU1: &mut *mut c_void,
+        CU2: &mut *mut c_void,
+    );
+    pub fn LLVMRustThinLTOPatchDICompileUnit(M: &Module, CU: *mut c_void);
 
     pub fn LLVMRustLinkerNew(M: &Module) -> &mut Linker<'_>;
     pub fn LLVMRustLinkerAdd(

compiler/rustc_infer/src/infer/mod.rs

@@ -1659,49 +1659,6 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> {
         self.tcx.const_eval_resolve(param_env_erased, unevaluated, span)
     }
 
-    /// If `typ` is a type variable of some kind, resolve it one level
-    /// (but do not resolve types found in the result). If `typ` is
-    /// not a type variable, just return it unmodified.
-    // FIXME(eddyb) inline into `ShallowResolver::visit_ty`.
-    fn shallow_resolve_ty(&self, typ: Ty<'tcx>) -> Ty<'tcx> {
-        match *typ.kind() {
-            ty::Infer(ty::TyVar(v)) => {
-                // Not entirely obvious: if `typ` is a type variable,
-                // it can be resolved to an int/float variable, which
-                // can then be recursively resolved, hence the
-                // recursion. Note though that we prevent type
-                // variables from unifying to other type variables
-                // directly (though they may be embedded
-                // structurally), and we prevent cycles in any case,
-                // so this recursion should always be of very limited
-                // depth.
-                //
-                // Note: if these two lines are combined into one we get
-                // dynamic borrow errors on `self.inner`.
-                let known = self.inner.borrow_mut().type_variables().probe(v).known();
-                known.map_or(typ, |t| self.shallow_resolve_ty(t))
-            }
-
-            ty::Infer(ty::IntVar(v)) => self
-                .inner
-                .borrow_mut()
-                .int_unification_table()
-                .probe_value(v)
-                .map(|v| v.to_type(self.tcx))
-                .unwrap_or(typ),
-
-            ty::Infer(ty::FloatVar(v)) => self
-                .inner
-                .borrow_mut()
-                .float_unification_table()
-                .probe_value(v)
-                .map(|v| v.to_type(self.tcx))
-                .unwrap_or(typ),
-
-            _ => typ,
-        }
-    }
-
     /// `ty_or_const_infer_var_changed` is equivalent to one of these two:
     ///   * `shallow_resolve(ty) != ty` (where `ty.kind = ty::Infer(_)`)
     ///   * `shallow_resolve(ct) != ct` (where `ct.kind = ty::ConstKind::Infer(_)`)
@@ -1831,8 +1788,46 @@ impl<'a, 'tcx> TypeFolder<'tcx> for ShallowResolver<'a, 'tcx> {
         self.infcx.tcx
     }
 
+    /// If `ty` is a type variable of some kind, resolve it one level
+    /// (but do not resolve types found in the result). If `typ` is
+    /// not a type variable, just return it unmodified.
     fn fold_ty(&mut self, ty: Ty<'tcx>) -> Ty<'tcx> {
-        self.infcx.shallow_resolve_ty(ty)
+        match *ty.kind() {
+            ty::Infer(ty::TyVar(v)) => {
+                // Not entirely obvious: if `typ` is a type variable,
+                // it can be resolved to an int/float variable, which
+                // can then be recursively resolved, hence the
+                // recursion. Note though that we prevent type
+                // variables from unifying to other type variables
+                // directly (though they may be embedded
+                // structurally), and we prevent cycles in any case,
+                // so this recursion should always be of very limited
+                // depth.
+                //
+                // Note: if these two lines are combined into one we get
+                // dynamic borrow errors on `self.inner`.
+                let known = self.infcx.inner.borrow_mut().type_variables().probe(v).known();
+                known.map_or(ty, |t| self.fold_ty(t))
+            }
+
+            ty::Infer(ty::IntVar(v)) => self
+                .infcx
+                .inner
+                .borrow_mut()
+                .int_unification_table()
+                .probe_value(v)
+                .map_or(ty, |v| v.to_type(self.infcx.tcx)),
+
+            ty::Infer(ty::FloatVar(v)) => self
+                .infcx
+                .inner
+                .borrow_mut()
+                .float_unification_table()
+                .probe_value(v)
+                .map_or(ty, |v| v.to_type(self.infcx.tcx)),
+
+            _ => ty,
+        }
     }
 
     fn fold_const(&mut self, ct: ty::Const<'tcx>) -> ty::Const<'tcx> {

compiler/rustc_interface/src/passes.rs

@@ -629,11 +629,15 @@ fn write_out_deps(
         });
         files.extend(extra_tracked_files);
 
-        if let Some(ref backend) = sess.opts.debugging_opts.codegen_backend {
-            files.push(backend.to_string());
-        }
-
         if sess.binary_dep_depinfo() {
+            if let Some(ref backend) = sess.opts.debugging_opts.codegen_backend {
+                if backend.contains('.') {
+                    // If the backend name contain a `.`, it is the path to an external dynamic
+                    // library. If not, it is not a path.
+                    files.push(backend.to_string());
+                }
+            }
+
             boxed_resolver.borrow_mut().access(|resolver| {
                 for cnum in resolver.cstore().crates_untracked() {
                     let source = resolver.cstore().crate_source_untracked(cnum);

compiler/rustc_llvm/llvm-wrapper/PassWrapper.cpp

@@ -1618,7 +1618,7 @@ LLVMRustGetBitcodeSliceFromObjectData(const char *data,
 // Rewrite all `DICompileUnit` pointers to the `DICompileUnit` specified. See
 // the comment in `back/lto.rs` for why this exists.
 extern "C" void
-LLVMRustLTOGetDICompileUnit(LLVMModuleRef Mod,
+LLVMRustThinLTOGetDICompileUnit(LLVMModuleRef Mod,
                                 DICompileUnit **A,
                                 DICompileUnit **B) {
   Module *M = unwrap(Mod);
@@ -1636,7 +1636,7 @@ LLVMRustLTOGetDICompileUnit(LLVMModuleRef Mod,
 // Rewrite all `DICompileUnit` pointers to the `DICompileUnit` specified. See
 // the comment in `back/lto.rs` for why this exists.
 extern "C" void
-LLVMRustLTOPatchDICompileUnit(LLVMModuleRef Mod, DICompileUnit *Unit) {
+LLVMRustThinLTOPatchDICompileUnit(LLVMModuleRef Mod, DICompileUnit *Unit) {
   Module *M = unwrap(Mod);
 
   // If the original source module didn't have a `DICompileUnit` then try to

compiler/rustc_parse/src/parser/mod.rs

@@ -1125,13 +1125,13 @@ impl<'a> Parser<'a> {
             self.sess.gated_spans.gate(sym::inline_const, span);
         }
         self.eat_keyword(kw::Const);
-        let blk = self.parse_block()?;
+        let (attrs, blk) = self.parse_inner_attrs_and_block()?;
         let anon_const = AnonConst {
             id: DUMMY_NODE_ID,
             value: self.mk_expr(blk.span, ExprKind::Block(blk, None), AttrVec::new()),
         };
         let blk_span = anon_const.value.span;
-        Ok(self.mk_expr(span.to(blk_span), ExprKind::ConstBlock(anon_const), AttrVec::new()))
+        Ok(self.mk_expr(span.to(blk_span), ExprKind::ConstBlock(anon_const), AttrVec::from(attrs)))
     }
 
     /// Parses mutability (`mut` or nothing).

compiler/rustc_parse/src/parser/ty.rs

@@ -523,6 +523,9 @@ impl<'a> Parser<'a> {
         let decl = self.parse_fn_decl(|_| false, AllowPlus::No, recover_return_sign)?;
         let whole_span = lo.to(self.prev_token.span);
         if let ast::Const::Yes(span) = constness {
+            // If we ever start to allow `const fn()`, then update
+            // feature gating for `#![feature(const_extern_fn)]` to
+            // cover it.
             self.error_fn_ptr_bad_qualifier(whole_span, span, "const");
         }
         if let ast::Async::Yes { span, .. } = asyncness {