Auto merge of #127614 - matthiaskrgr:rollup-8geziwi, r=matthiaskrgr

Rollup of 8 pull requests

Successful merges:

 - #124599 (Suggest borrowing on fn argument that is `impl AsRef`)
 - #127572 (Don't mark `DEBUG_EVENT` struct as `repr(packed)`)
 - #127588 (core: Limit remaining f16 doctests to x86_64 linux)
 - #127591 (Make sure that labels are defined after the primary span in diagnostics)
 - #127598 (Allows `#[diagnostic::do_not_recommend]` to supress trait impls in suggestions as well)
 - #127599 (Rename `lazy_cell_consume` to `lazy_cell_into_inner`)
 - #127601 (check is_ident before parse_ident)
 - #127605 (Remove extern "wasm" ABI)

r? `@ghost`
`@rustbot` modify labels: rollup

compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs

@@ -445,31 +445,81 @@ impl<'infcx, 'tcx> MirBorrowckCtxt<'_, '_, 'infcx, 'tcx> {
                 } else {
                     (None, &[][..], 0)
                 };
+                let mut can_suggest_clone = true;
                 if let Some(def_id) = def_id
                     && let node = self.infcx.tcx.hir_node_by_def_id(def_id)
                     && let Some(fn_sig) = node.fn_sig()
                     && let Some(ident) = node.ident()
                     && let Some(pos) = args.iter().position(|arg| arg.hir_id == expr.hir_id)
                     && let Some(arg) = fn_sig.decl.inputs.get(pos + offset)
                 {
-                    let mut span: MultiSpan = arg.span.into();
-                    span.push_span_label(
-                        arg.span,
-                        "this parameter takes ownership of the value".to_string(),
-                    );
-                    let descr = match node.fn_kind() {
-                        Some(hir::intravisit::FnKind::ItemFn(..)) | None => "function",
-                        Some(hir::intravisit::FnKind::Method(..)) => "method",
-                        Some(hir::intravisit::FnKind::Closure) => "closure",
-                    };
-                    span.push_span_label(ident.span, format!("in this {descr}"));
-                    err.span_note(
-                        span,
-                        format!(
-                            "consider changing this parameter type in {descr} `{ident}` to borrow \
-                             instead if owning the value isn't necessary",
-                        ),
-                    );
+                    let mut is_mut = false;
+                    if let hir::TyKind::Path(hir::QPath::Resolved(None, path)) = arg.kind
+                        && let Res::Def(DefKind::TyParam, param_def_id) = path.res
+                        && self
+                            .infcx
+                            .tcx
+                            .predicates_of(def_id)
+                            .instantiate_identity(self.infcx.tcx)
+                            .predicates
+                            .into_iter()
+                            .any(|pred| {
+                                if let ty::ClauseKind::Trait(predicate) = pred.kind().skip_binder()
+                                    && [
+                                        self.infcx.tcx.get_diagnostic_item(sym::AsRef),
+                                        self.infcx.tcx.get_diagnostic_item(sym::AsMut),
+                                        self.infcx.tcx.get_diagnostic_item(sym::Borrow),
+                                        self.infcx.tcx.get_diagnostic_item(sym::BorrowMut),
+                                    ]
+                                    .contains(&Some(predicate.def_id()))
+                                    && let ty::Param(param) = predicate.self_ty().kind()
+                                    && let generics = self.infcx.tcx.generics_of(def_id)
+                                    && let param = generics.type_param(*param, self.infcx.tcx)
+                                    && param.def_id == param_def_id
+                                {
+                                    if [
+                                        self.infcx.tcx.get_diagnostic_item(sym::AsMut),
+                                        self.infcx.tcx.get_diagnostic_item(sym::BorrowMut),
+                                    ]
+                                    .contains(&Some(predicate.def_id()))
+                                    {
+                                        is_mut = true;
+                                    }
+                                    true
+                                } else {
+                                    false
+                                }
+                            })
+                    {
+                        // The type of the argument corresponding to the expression that got moved
+                        // is a type parameter `T`, which is has a `T: AsRef` obligation.
+                        err.span_suggestion_verbose(
+                            expr.span.shrink_to_lo(),
+                            "borrow the value to avoid moving it",
+                            format!("&{}", if is_mut { "mut " } else { "" }),
+                            Applicability::MachineApplicable,
+                        );
+                        can_suggest_clone = is_mut;
+                    } else {
+                        let mut span: MultiSpan = arg.span.into();
+                        span.push_span_label(
+                            arg.span,
+                            "this parameter takes ownership of the value".to_string(),
+                        );
+                        let descr = match node.fn_kind() {
+                            Some(hir::intravisit::FnKind::ItemFn(..)) | None => "function",
+                            Some(hir::intravisit::FnKind::Method(..)) => "method",
+                            Some(hir::intravisit::FnKind::Closure) => "closure",
+                        };
+                        span.push_span_label(ident.span, format!("in this {descr}"));
+                        err.span_note(
+                            span,
+                            format!(
+                                "consider changing this parameter type in {descr} `{ident}` to \
+                                 borrow instead if owning the value isn't necessary",
+                            ),
+                        );
+                    }
                 }
                 let place = &self.move_data.move_paths[mpi].place;
                 let ty = place.ty(self.body, self.infcx.tcx).ty;
@@ -487,9 +537,10 @@ impl<'infcx, 'tcx> MirBorrowckCtxt<'_, '_, 'infcx, 'tcx> {
                         ClosureKind::Coroutine(CoroutineKind::Desugared(_, CoroutineSource::Block)),
                     ..
                 } = move_spans
+                    && can_suggest_clone
                 {
                     self.suggest_cloning(err, ty, expr, None, Some(move_spans));
-                } else if self.suggest_hoisting_call_outside_loop(err, expr) {
+                } else if self.suggest_hoisting_call_outside_loop(err, expr) && can_suggest_clone {
                     // The place where the type moves would be misleading to suggest clone.
                     // #121466
                     self.suggest_cloning(err, ty, expr, None, Some(move_spans));

compiler/rustc_codegen_llvm/src/attributes.rs

@@ -6,7 +6,6 @@ use rustc_middle::middle::codegen_fn_attrs::{CodegenFnAttrFlags, PatchableFuncti
 use rustc_middle::ty::{self, TyCtxt};
 use rustc_session::config::{FunctionReturn, OptLevel};
 use rustc_span::symbol::sym;
-use rustc_target::spec::abi::Abi;
 use rustc_target::spec::{FramePointer, SanitizerSet, StackProbeType, StackProtector};
 use smallvec::SmallVec;
 
@@ -482,7 +481,7 @@ pub fn from_fn_attrs<'ll, 'tcx>(
         return;
     }
 
-    let mut function_features = function_features
+    let function_features = function_features
         .iter()
         .flat_map(|feat| {
             llvm_util::to_llvm_features(cx.tcx.sess, feat).into_iter().map(|f| format!("+{f}"))
@@ -504,17 +503,6 @@ pub fn from_fn_attrs<'ll, 'tcx>(
             let name = name.as_str();
             to_add.push(llvm::CreateAttrStringValue(cx.llcx, "wasm-import-name", name));
         }
-
-        // The `"wasm"` abi on wasm targets automatically enables the
-        // `+multivalue` feature because the purpose of the wasm abi is to match
-        // the WebAssembly specification, which has this feature. This won't be
-        // needed when LLVM enables this `multivalue` feature by default.
-        if !cx.tcx.is_closure_like(instance.def_id()) {
-            let abi = cx.tcx.fn_sig(instance.def_id()).skip_binder().abi();
-            if abi == Abi::Wasm {
-                function_features.push("+multivalue".to_string());
-            }
-        }
     }
 
     let global_features = cx.tcx.global_backend_features(()).iter().map(|s| s.as_str());

compiler/rustc_feature/src/removed.rs

@@ -215,6 +215,9 @@ declare_features! (
     /// Permits specifying whether a function should permit unwinding or abort on unwind.
     (removed, unwind_attributes, "1.56.0", Some(58760), Some("use the C-unwind ABI instead")),
     (removed, visible_private_types, "1.0.0", None, None),
+    /// Allows `extern "wasm" fn`
+    (removed, wasm_abi, "CURRENT_RUSTC_VERSION", Some(83788),
+     Some("non-standard wasm ABI is no longer supported")),
     // !!!!    !!!!    !!!!    !!!!   !!!!    !!!!    !!!!    !!!!    !!!!    !!!!    !!!!
     // Features are listed in alphabetical order. Tidy will fail if you don't keep it this way.
     // !!!!    !!!!    !!!!    !!!!   !!!!    !!!!    !!!!    !!!!    !!!!    !!!!    !!!!

compiler/rustc_feature/src/unstable.rs

@@ -640,8 +640,6 @@ declare_features! (
     (unstable, unsized_tuple_coercion, "1.20.0", Some(42877)),
     /// Allows using the `#[used(linker)]` (or `#[used(compiler)]`) attribute.
     (unstable, used_with_arg, "1.60.0", Some(93798)),
-    /// Allows `extern "wasm" fn`
-    (unstable, wasm_abi, "1.53.0", Some(83788)),
     /// Allows `do yeet` expressions
     (unstable, yeet_expr, "1.62.0", Some(96373)),
     // !!!!    !!!!    !!!!    !!!!   !!!!    !!!!    !!!!    !!!!    !!!!    !!!!    !!!!

compiler/rustc_macros/src/diagnostics/diagnostic_builder.rs

@@ -269,6 +269,7 @@ impl DiagnosticDeriveVariantBuilder {
         let field_binding = &binding_info.binding;
 
         let inner_ty = FieldInnerTy::from_type(&field.ty);
+        let mut seen_label = false;
 
         field
             .attrs
@@ -280,6 +281,14 @@ impl DiagnosticDeriveVariantBuilder {
                 }
 
                 let name = attr.path().segments.last().unwrap().ident.to_string();
+
+                if name == "primary_span" && seen_label {
+                    span_err(attr.span().unwrap(), format!("`#[primary_span]` must be placed before labels, since it overwrites the span of the diagnostic")).emit();
+                }
+                if name == "label" {
+                    seen_label = true;
+                }
+
                 let needs_clone =
                     name == "primary_span" && matches!(inner_ty, FieldInnerTy::Vec(_));
                 let (binding, needs_destructure) = if needs_clone {

compiler/rustc_middle/src/ty/layout.rs

@@ -1212,7 +1212,6 @@ pub fn fn_can_unwind(tcx: TyCtxt<'_>, fn_def_id: Option<DefId>, abi: SpecAbi) ->
         | RiscvInterruptM
         | RiscvInterruptS
         | CCmseNonSecureCall
-        | Wasm
         | Unadjusted => false,
         Rust | RustCall | RustCold | RustIntrinsic => {
             tcx.sess.panic_strategy() == PanicStrategy::Unwind

compiler/rustc_parse/src/parser/item.rs

@@ -387,8 +387,8 @@ impl<'a> Parser<'a> {
         let span = if is_pub { self.prev_token.span.to(ident_span) } else { ident_span };
         let insert_span = ident_span.shrink_to_lo();
 
-        let ident = if (!is_const
-            || self.look_ahead(1, |t| *t == token::OpenDelim(Delimiter::Parenthesis)))
+        let ident = if self.token.is_ident()
+            && (!is_const || self.look_ahead(1, |t| *t == token::OpenDelim(Delimiter::Parenthesis)))
             && self.look_ahead(1, |t| {
                 [
                     token::Lt,

compiler/rustc_resolve/src/errors.rs

@@ -1089,8 +1089,8 @@ pub(crate) struct ToolWasAlreadyRegistered {
 #[derive(Diagnostic)]
 #[diag(resolve_tool_only_accepts_identifiers)]
 pub(crate) struct ToolOnlyAcceptsIdentifiers {
-    #[label]
     #[primary_span]
+    #[label]
     pub(crate) span: Span,
     pub(crate) tool: Symbol,
 }

compiler/rustc_smir/src/rustc_internal/internal.rs

@@ -466,7 +466,6 @@ impl RustcInternal for Abi {
             Abi::AvrInterrupt => rustc_target::spec::abi::Abi::AvrInterrupt,
             Abi::AvrNonBlockingInterrupt => rustc_target::spec::abi::Abi::AvrNonBlockingInterrupt,
             Abi::CCmseNonSecureCall => rustc_target::spec::abi::Abi::CCmseNonSecureCall,
-            Abi::Wasm => rustc_target::spec::abi::Abi::Wasm,
             Abi::System { unwind } => rustc_target::spec::abi::Abi::System { unwind },
             Abi::RustIntrinsic => rustc_target::spec::abi::Abi::RustIntrinsic,
             Abi::RustCall => rustc_target::spec::abi::Abi::RustCall,

compiler/rustc_smir/src/rustc_smir/convert/ty.rs

@@ -909,7 +909,6 @@ impl<'tcx> Stable<'tcx> for rustc_target::spec::abi::Abi {
             abi::Abi::AvrInterrupt => Abi::AvrInterrupt,
             abi::Abi::AvrNonBlockingInterrupt => Abi::AvrNonBlockingInterrupt,
             abi::Abi::CCmseNonSecureCall => Abi::CCmseNonSecureCall,
-            abi::Abi::Wasm => Abi::Wasm,
             abi::Abi::System { unwind } => Abi::System { unwind },
             abi::Abi::RustIntrinsic => Abi::RustIntrinsic,
             abi::Abi::RustCall => Abi::RustCall,

compiler/rustc_target/src/abi/call/mod.rs

@@ -1,6 +1,6 @@
 use crate::abi::{self, Abi, Align, FieldsShape, Size};
 use crate::abi::{HasDataLayout, TyAbiInterface, TyAndLayout};
-use crate::spec::{self, HasTargetSpec, HasWasmCAbiOpt};
+use crate::spec::{self, HasTargetSpec, HasWasmCAbiOpt, WasmCAbi};
 use rustc_macros::HashStable_Generic;
 use rustc_span::Symbol;
 use std::fmt;
@@ -854,7 +854,8 @@ impl<'a, Ty> FnAbi<'a, Ty> {
             return Ok(());
         }
 
-        match &cx.target_spec().arch[..] {
+        let spec = cx.target_spec();
+        match &spec.arch[..] {
             "x86" => {
                 let flavor = if let spec::abi::Abi::Fastcall { .. }
                 | spec::abi::Abi::Vectorcall { .. } = abi
@@ -901,9 +902,7 @@ impl<'a, Ty> FnAbi<'a, Ty> {
             "sparc" => sparc::compute_abi_info(cx, self),
             "sparc64" => sparc64::compute_abi_info(cx, self),
             "nvptx64" => {
-                if cx.target_spec().adjust_abi(cx, abi, self.c_variadic)
-                    == spec::abi::Abi::PtxKernel
-                {
+                if cx.target_spec().adjust_abi(abi, self.c_variadic) == spec::abi::Abi::PtxKernel {
                     nvptx64::compute_ptx_kernel_abi_info(cx, self)
                 } else {
                     nvptx64::compute_abi_info(self)
@@ -912,13 +911,14 @@ impl<'a, Ty> FnAbi<'a, Ty> {
             "hexagon" => hexagon::compute_abi_info(self),
             "xtensa" => xtensa::compute_abi_info(cx, self),
             "riscv32" | "riscv64" => riscv::compute_abi_info(cx, self),
-            "wasm32" | "wasm64" => {
-                if cx.target_spec().adjust_abi(cx, abi, self.c_variadic) == spec::abi::Abi::Wasm {
+            "wasm32" => {
+                if spec.os == "unknown" && cx.wasm_c_abi_opt() == WasmCAbi::Legacy {
                     wasm::compute_wasm_abi_info(self)
                 } else {
                     wasm::compute_c_abi_info(cx, self)
                 }
             }
+            "wasm64" => wasm::compute_c_abi_info(cx, self),
             "bpf" => bpf::compute_abi_info(self),
             arch => {
                 return Err(AdjustForForeignAbiError::Unsupported {

compiler/rustc_target/src/spec/abi/mod.rs

@@ -48,7 +48,6 @@ pub enum Abi {
     AvrInterrupt,
     AvrNonBlockingInterrupt,
     CCmseNonSecureCall,
-    Wasm,
     System {
         unwind: bool,
     },
@@ -123,7 +122,6 @@ const AbiDatas: &[AbiData] = &[
     AbiData { abi: Abi::AvrInterrupt, name: "avr-interrupt" },
     AbiData { abi: Abi::AvrNonBlockingInterrupt, name: "avr-non-blocking-interrupt" },
     AbiData { abi: Abi::CCmseNonSecureCall, name: "C-cmse-nonsecure-call" },
-    AbiData { abi: Abi::Wasm, name: "wasm" },
     AbiData { abi: Abi::System { unwind: false }, name: "system" },
     AbiData { abi: Abi::System { unwind: true }, name: "system-unwind" },
     AbiData { abi: Abi::RustIntrinsic, name: "rust-intrinsic" },
@@ -149,6 +147,9 @@ pub fn lookup(name: &str) -> Result<Abi, AbiUnsupported> {
         "riscv-interrupt-u" => AbiUnsupported::Reason {
             explain: "user-mode interrupt handlers have been removed from LLVM pending standardization, see: https://reviews.llvm.org/D149314",
         },
+        "wasm" => AbiUnsupported::Reason {
+            explain: "non-standard wasm ABI is no longer supported",
+        },
 
         _ => AbiUnsupported::Unrecognized,
 
@@ -241,10 +242,6 @@ pub fn is_stable(name: &str) -> Result<(), AbiDisabled> {
             feature: sym::abi_c_cmse_nonsecure_call,
             explain: "C-cmse-nonsecure-call ABI is experimental and subject to change",
         }),
-        "wasm" => Err(AbiDisabled::Unstable {
-            feature: sym::wasm_abi,
-            explain: "wasm ABI is experimental and subject to change",
-        }),
         _ => Err(AbiDisabled::Unrecognized),
     }
 }
@@ -287,16 +284,15 @@ impl Abi {
             AvrInterrupt => 23,
             AvrNonBlockingInterrupt => 24,
             CCmseNonSecureCall => 25,
-            Wasm => 26,
             // Cross-platform ABIs
-            System { unwind: false } => 27,
-            System { unwind: true } => 28,
-            RustIntrinsic => 29,
-            RustCall => 30,
-            Unadjusted => 31,
-            RustCold => 32,
-            RiscvInterruptM => 33,
-            RiscvInterruptS => 34,
+            System { unwind: false } => 26,
+            System { unwind: true } => 27,
+            RustIntrinsic => 28,
+            RustCall => 29,
+            Unadjusted => 30,
+            RustCold => 31,
+            RiscvInterruptM => 32,
+            RiscvInterruptS => 33,
         };
         debug_assert!(
             AbiDatas

compiler/rustc_target/src/spec/mod.rs

@@ -2608,22 +2608,8 @@ impl DerefMut for Target {
 
 impl Target {
     /// Given a function ABI, turn it into the correct ABI for this target.
-    pub fn adjust_abi<C>(&self, cx: &C, abi: Abi, c_variadic: bool) -> Abi
-    where
-        C: HasWasmCAbiOpt,
-    {
+    pub fn adjust_abi(&self, abi: Abi, c_variadic: bool) -> Abi {
         match abi {
-            Abi::C { .. } => {
-                if self.arch == "wasm32"
-                    && self.os == "unknown"
-                    && cx.wasm_c_abi_opt() == WasmCAbi::Legacy
-                {
-                    Abi::Wasm
-                } else {
-                    abi
-                }
-            }
-
             // On Windows, `extern "system"` behaves like msvc's `__stdcall`.
             // `__stdcall` only applies on x86 and on non-variadic functions:
             // https://learn.microsoft.com/en-us/cpp/cpp/stdcall?view=msvc-170
@@ -2676,7 +2662,6 @@ impl Target {
             Msp430Interrupt => self.arch == "msp430",
             RiscvInterruptM | RiscvInterruptS => ["riscv32", "riscv64"].contains(&&self.arch[..]),
             AvrInterrupt | AvrNonBlockingInterrupt => self.arch == "avr",
-            Wasm => ["wasm32", "wasm64"].contains(&&self.arch[..]),
             Thiscall { .. } => self.arch == "x86",
             // On windows these fall-back to platform native calling convention (C) when the
             // architecture is not supported.