Rollup of 5 pull requests

.github/workflows/ci.yml

@@ -289,8 +289,9 @@ jobs:
             os: ubuntu-20.04-4core-16gb
             env: {}
           - name: x86_64-gnu-integration
+            env:
+              CI_ONLY_WHEN_CHANNEL: nightly
             os: ubuntu-20.04-16core-64gb
-            env: {}
           - name: x86_64-gnu-debug
             os: ubuntu-20.04-8core-32gb
             env: {}

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

@@ -5,7 +5,6 @@ use crate::pprust::state::{AnnNode, PrintState, State, INDENT_UNIT};
 use ast::StaticItem;
 use itertools::{Itertools, Position};
 use rustc_ast as ast;
-use rustc_ast::GenericBound;
 use rustc_ast::ModKind;
 use rustc_span::symbol::Ident;
 
@@ -338,21 +337,9 @@ impl<'a> State<'a> {
                 self.word_nbsp("trait");
                 self.print_ident(item.ident);
                 self.print_generic_params(&generics.params);
-                let mut real_bounds = Vec::with_capacity(bounds.len());
-                for bound in bounds.iter() {
-                    if let GenericBound::Trait(ptr, modifiers) = bound
-                        && let ast::BoundPolarity::Maybe(_) = modifiers.polarity
-                    {
-                        self.space();
-                        self.word_space("for ?");
-                        self.print_trait_ref(&ptr.trait_ref);
-                    } else {
-                        real_bounds.push(bound.clone());
-                    }
-                }
-                if !real_bounds.is_empty() {
+                if !bounds.is_empty() {
                     self.word_nbsp(":");
-                    self.print_type_bounds(&real_bounds);
+                    self.print_type_bounds(bounds);
                 }
                 self.print_where_clause(&generics.where_clause);
                 self.word(" ");

compiler/rustc_hir_analysis/src/check/entry.rs

@@ -124,7 +124,10 @@ fn check_main_fn_ty(tcx: TyCtxt<'_>, main_def_id: DefId) {
     if let Some(term_did) = tcx.lang_items().termination() {
         let return_ty = main_fnsig.output();
         let return_ty_span = main_fn_return_type_span(tcx, main_def_id).unwrap_or(main_span);
-        let return_ty = return_ty.skip_binder();
+        let Some(return_ty) = return_ty.no_bound_vars() else {
+            tcx.sess.emit_err(errors::MainFunctionReturnTypeGeneric { span: return_ty_span });
+            return;
+        };
         let infcx = tcx.infer_ctxt().build();
         let cause = traits::ObligationCause::new(
             return_ty_span,

compiler/rustc_hir_pretty/src/lib.rs

@@ -553,17 +553,7 @@ impl<'a> State<'a> {
             }
             hir::ItemKind::OpaqueTy(opaque_ty) => {
                 self.print_item_type(item, opaque_ty.generics, |state| {
-                    let mut real_bounds = Vec::with_capacity(opaque_ty.bounds.len());
-                    for b in opaque_ty.bounds {
-                        if let GenericBound::Trait(ptr, hir::TraitBoundModifier::Maybe) = b {
-                            state.space();
-                            state.word_space("for ?");
-                            state.print_trait_ref(&ptr.trait_ref);
-                        } else {
-                            real_bounds.push(b);
-                        }
-                    }
-                    state.print_bounds("= impl", real_bounds);
+                    state.print_bounds("= impl", opaque_ty.bounds)
                 });
             }
             hir::ItemKind::Enum(ref enum_definition, params) => {
@@ -625,17 +615,7 @@ impl<'a> State<'a> {
                 self.word_nbsp("trait");
                 self.print_ident(item.ident);
                 self.print_generic_params(generics.params);
-                let mut real_bounds = Vec::with_capacity(bounds.len());
-                for b in bounds {
-                    if let GenericBound::Trait(ptr, hir::TraitBoundModifier::Maybe) = b {
-                        self.space();
-                        self.word_space("for ?");
-                        self.print_trait_ref(&ptr.trait_ref);
-                    } else {
-                        real_bounds.push(b);
-                    }
-                }
-                self.print_bounds(":", real_bounds);
+                self.print_bounds(":", bounds);
                 self.print_where_clause(generics);
                 self.word(" ");
                 self.bopen();

compiler/rustc_target/src/spec/mod.rs

@@ -1493,6 +1493,7 @@ supported_targets! {
     ("mips64-unknown-linux-muslabi64", mips64_unknown_linux_muslabi64),
     ("mips64el-unknown-linux-muslabi64", mips64el_unknown_linux_muslabi64),
     ("hexagon-unknown-linux-musl", hexagon_unknown_linux_musl),
+    ("hexagon-unknown-none-elf", hexagon_unknown_none_elf),
 
     ("mips-unknown-linux-uclibc", mips_unknown_linux_uclibc),
     ("mipsel-unknown-linux-uclibc", mipsel_unknown_linux_uclibc),

compiler/rustc_target/src/spec/targets/hexagon_unknown_none_elf.rs

@@ -0,0 +1,27 @@
+use crate::spec::{PanicStrategy, Target, TargetOptions};
+
+pub fn target() -> Target {
+    Target {
+        llvm_target: "hexagon-unknown-none-elf".into(),
+        pointer_width: 32,
+        data_layout: concat!(
+            "e-m:e-p:32:32:32-a:0-n16:32-i64:64:64-i32:32",
+            ":32-i16:16:16-i1:8:8-f32:32:32-f64:64:64-v32",
+            ":32:32-v64:64:64-v512:512:512-v1024:1024:1024-v2048",
+            ":2048:2048"
+        )
+        .into(),
+        arch: "hexagon".into(),
+
+        options: TargetOptions {
+            cpu: "hexagonv60".into(),
+            panic_strategy: PanicStrategy::Abort,
+            dynamic_linking: true,
+            features: "-small-data,+hvx-length128b".into(),
+            max_atomic_width: Some(32),
+            emit_debug_gdb_scripts: false,
+            c_enum_min_bits: Some(8),
+            ..Default::default()
+        },
+    }
+}

compiler/rustc_target/src/spec/tests/tests_impl.rs

@@ -116,7 +116,8 @@ impl Target {
 
         // Check dynamic linking stuff
         // BPF: when targeting user space vms (like rbpf), those can load dynamic libraries.
-        if self.os == "none" && self.arch != "bpf" {
+        // hexagon: when targeting QuRT, that OS can load dynamic libraries.
+        if self.os == "none" && (self.arch != "bpf" && self.arch != "hexagon") {
             assert!(!self.dynamic_linking);
         }
         if self.only_cdylib

src/ci/github-actions/ci.yml

@@ -471,6 +471,11 @@ jobs:
             <<: *job-linux-4c
 
           - name: x86_64-gnu-integration
+            env:
+              # Only run this job on the nightly channel. Fuchsia requires
+              # nightly features to compile, and this job would fail if
+              # executed on beta and stable.
+              CI_ONLY_WHEN_CHANNEL: nightly
             <<: *job-linux-16c
 
           - name: x86_64-gnu-debug

src/doc/rustc/src/SUMMARY.md

@@ -38,6 +38,7 @@
     - [\*-unknown-fuchsia](platform-support/fuchsia.md)
     - [\*-kmc-solid_\*](platform-support/kmc-solid.md)
     - [csky-unknown-linux-gnuabiv2\*](platform-support/csky-unknown-linux-gnuabiv2.md)
+    - [hexagon-unknown-none-elf](platform-support/hexagon-unknown-none-elf.md)
     - [loongarch\*-unknown-linux-\*](platform-support/loongarch-linux.md)
     - [loongarch\*-unknown-none\*](platform-support/loongarch-none.md)
     - [m68k-unknown-linux-gnu](platform-support/m68k-unknown-linux-gnu.md)

src/doc/rustc/src/platform-support.md

@@ -265,6 +265,7 @@ target | std | host | notes
 `bpfel-unknown-none` | * |  | BPF (little endian)
 `csky-unknown-linux-gnuabiv2` | ✓ |  | C-SKY abiv2 Linux (little endian)
 `csky-unknown-linux-gnuabiv2hf` | ✓ |  | C-SKY abiv2 Linux, hardfloat (little endian)
+[`hexagon-unknown-none-elf`](platform-support/hexagon-unknown-none-elf.md)| * | Bare Hexagon (v60+, HVX)
 `hexagon-unknown-linux-musl` | ? |  |
 `i386-apple-ios` | ✓ |  | 32-bit x86 iOS [^x86_32-floats-return-ABI]
 [`i586-pc-nto-qnx700`](platform-support/nto-qnx.md) | * |  | 32-bit x86 QNX Neutrino 7.0 RTOS  [^x86_32-floats-return-ABI]