Auto merge of #104600 - Dylan-DPC:rollup-glw1e8b, r=Dylan-DPC

Rollup of 8 pull requests

Successful merges:

 - #104001 (Improve generating Custom entry function)
 - #104411 (nll: correctly deal with bivariance)
 - #104528 (Properly link `{Once,Lazy}{Cell,Lock}` in docs)
 - #104553 (Improve accuracy of asinh and acosh)
 - #104554 (Use `ErrorGuaranteed::unchecked_claim_error_was_emitted` less)
 - #104566 (couple of clippy::perf fixes)
 - #104575 (deduplicate tests)
 - #104580 (diagnostics: only show one suggestion for method -> assoc fn)

Failed merges:

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

Author: bors

compiler/rustc_borrowck/src/lib.rs

@@ -19,7 +19,7 @@ extern crate tracing;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_data_structures::graph::dominators::Dominators;
 use rustc_data_structures::vec_map::VecMap;
-use rustc_errors::{Diagnostic, DiagnosticBuilder, ErrorGuaranteed};
+use rustc_errors::{Diagnostic, DiagnosticBuilder};
 use rustc_hir as hir;
 use rustc_hir::def_id::LocalDefId;
 use rustc_index::bit_set::ChunkedBitSet;
@@ -192,13 +192,13 @@ fn do_mir_borrowck<'tcx>(
         }
     }
 
-    let mut errors = error::BorrowckErrors::new();
+    let mut errors = error::BorrowckErrors::new(infcx.tcx);
 
     // Gather the upvars of a closure, if any.
     let tables = tcx.typeck_opt_const_arg(def);
-    if let Some(ErrorGuaranteed { .. }) = tables.tainted_by_errors {
-        infcx.set_tainted_by_errors();
-        errors.set_tainted_by_errors();
+    if let Some(e) = tables.tainted_by_errors {
+        infcx.set_tainted_by_errors(e);
+        errors.set_tainted_by_errors(e);
     }
     let upvars: Vec<_> = tables
         .closure_min_captures_flattened(def.did)
@@ -2260,6 +2260,7 @@ mod error {
     use super::*;
 
     pub struct BorrowckErrors<'tcx> {
+        tcx: TyCtxt<'tcx>,
         /// This field keeps track of move errors that are to be reported for given move indices.
         ///
         /// There are situations where many errors can be reported for a single move out (see #53807)
@@ -2282,28 +2283,33 @@ mod error {
         tainted_by_errors: Option<ErrorGuaranteed>,
     }
 
-    impl BorrowckErrors<'_> {
-        pub fn new() -> Self {
+    impl<'tcx> BorrowckErrors<'tcx> {
+        pub fn new(tcx: TyCtxt<'tcx>) -> Self {
             BorrowckErrors {
+                tcx,
                 buffered_move_errors: BTreeMap::new(),
                 buffered: Default::default(),
                 tainted_by_errors: None,
             }
         }
 
-        // FIXME(eddyb) this is a suboptimal API because `tainted_by_errors` is
-        // set before any emission actually happens (weakening the guarantee).
         pub fn buffer_error(&mut self, t: DiagnosticBuilder<'_, ErrorGuaranteed>) {
-            self.tainted_by_errors = Some(ErrorGuaranteed::unchecked_claim_error_was_emitted());
+            if let None = self.tainted_by_errors {
+                self.tainted_by_errors = Some(
+                    self.tcx
+                        .sess
+                        .delay_span_bug(t.span.clone(), "diagnostic buffered but not emitted"),
+                )
+            }
             t.buffer(&mut self.buffered);
         }
 
         pub fn buffer_non_error_diag(&mut self, t: DiagnosticBuilder<'_, ()>) {
             t.buffer(&mut self.buffered);
         }
 
-        pub fn set_tainted_by_errors(&mut self) {
-            self.tainted_by_errors = Some(ErrorGuaranteed::unchecked_claim_error_was_emitted());
+        pub fn set_tainted_by_errors(&mut self, e: ErrorGuaranteed) {
+            self.tainted_by_errors = Some(e);
         }
     }
 

compiler/rustc_borrowck/src/nll.rs

@@ -303,7 +303,10 @@ pub(crate) fn compute_regions<'cx, 'tcx>(
 
     if !nll_errors.is_empty() {
         // Suppress unhelpful extra errors in `infer_opaque_types`.
-        infcx.set_tainted_by_errors();
+        infcx.set_tainted_by_errors(infcx.tcx.sess.delay_span_bug(
+            body.span,
+            "`compute_regions` tainted `infcx` with errors but did not emit any errors",
+        ));
     }
 
     let remapped_opaque_tys = regioncx.infer_opaque_types(&infcx, opaque_type_values);

compiler/rustc_borrowck/src/region_infer/opaque_types.rs

@@ -219,8 +219,8 @@ impl<'tcx> InferCtxtExt<'tcx> for InferCtxt<'tcx> {
         instantiated_ty: OpaqueHiddenType<'tcx>,
         origin: OpaqueTyOrigin,
     ) -> Ty<'tcx> {
-        if self.is_tainted_by_errors() {
-            return self.tcx.ty_error();
+        if let Some(e) = self.tainted_by_errors() {
+            return self.tcx.ty_error_with_guaranteed(e);
         }
 
         let definition_ty = instantiated_ty

compiler/rustc_codegen_cranelift/src/abi/mod.rs

@@ -22,7 +22,19 @@ fn clif_sig_from_fn_abi<'tcx>(
     default_call_conv: CallConv,
     fn_abi: &FnAbi<'tcx, Ty<'tcx>>,
 ) -> Signature {
-    let call_conv = match fn_abi.conv {
+    let call_conv = conv_to_call_conv(fn_abi.conv, default_call_conv);
+
+    let inputs = fn_abi.args.iter().map(|arg_abi| arg_abi.get_abi_param(tcx).into_iter()).flatten();
+
+    let (return_ptr, returns) = fn_abi.ret.get_abi_return(tcx);
+    // Sometimes the first param is an pointer to the place where the return value needs to be stored.
+    let params: Vec<_> = return_ptr.into_iter().chain(inputs).collect();
+
+    Signature { params, returns, call_conv }
+}
+
+pub(crate) fn conv_to_call_conv(c: Conv, default_call_conv: CallConv) -> CallConv {
+    match c {
         Conv::Rust | Conv::C => default_call_conv,
         Conv::RustCold => CallConv::Cold,
         Conv::X86_64SysV => CallConv::SystemV,
@@ -38,15 +50,8 @@ fn clif_sig_from_fn_abi<'tcx>(
         | Conv::X86VectorCall
         | Conv::AmdGpuKernel
         | Conv::AvrInterrupt
-        | Conv::AvrNonBlockingInterrupt => todo!("{:?}", fn_abi.conv),
-    };
-    let inputs = fn_abi.args.iter().map(|arg_abi| arg_abi.get_abi_param(tcx).into_iter()).flatten();
-
-    let (return_ptr, returns) = fn_abi.ret.get_abi_return(tcx);
-    // Sometimes the first param is an pointer to the place where the return value needs to be stored.
-    let params: Vec<_> = return_ptr.into_iter().chain(inputs).collect();
-
-    Signature { params, returns, call_conv }
+        | Conv::AvrNonBlockingInterrupt => todo!("{:?}", c),
+    }
 }
 
 pub(crate) fn get_function_sig<'tcx>(

compiler/rustc_codegen_cranelift/src/main_shim.rs

@@ -63,10 +63,14 @@ pub(crate) fn maybe_create_entry_wrapper(
                 AbiParam::new(m.target_config().pointer_type()),
             ],
             returns: vec![AbiParam::new(m.target_config().pointer_type() /*isize*/)],
-            call_conv: CallConv::triple_default(m.isa().triple()),
+            call_conv: crate::conv_to_call_conv(
+                tcx.sess.target.options.entry_abi,
+                CallConv::triple_default(m.isa().triple()),
+            ),
         };
 
-        let cmain_func_id = m.declare_function("main", Linkage::Export, &cmain_sig).unwrap();
+        let entry_name = tcx.sess.target.options.entry_name.as_ref();
+        let cmain_func_id = m.declare_function(entry_name, Linkage::Export, &cmain_sig).unwrap();
 
         let instance = Instance::mono(tcx, rust_main_def_id).polymorphize(tcx);
 

compiler/rustc_codegen_gcc/src/context.rs

@@ -425,8 +425,9 @@ impl<'gcc, 'tcx> MiscMethods<'tcx> for CodegenCx<'gcc, 'tcx> {
     }
 
     fn declare_c_main(&self, fn_type: Self::Type) -> Option<Self::Function> {
-        if self.get_declared_value("main").is_none() {
-            Some(self.declare_cfn("main", fn_type))
+        let entry_name = self.sess().target.entry_name.as_ref();
+        if self.get_declared_value(entry_name).is_none() {
+            Some(self.declare_entry_fn(entry_name, fn_type, ()))
         }
         else {
             // If the symbol already exists, it is an error: for example, the user wrote

compiler/rustc_codegen_gcc/src/declare.rs

@@ -65,13 +65,13 @@ impl<'gcc, 'tcx> CodegenCx<'gcc, 'tcx> {
         global
     }
 
-    pub fn declare_cfn(&self, name: &str, _fn_type: Type<'gcc>) -> RValue<'gcc> {
+    pub fn declare_entry_fn(&self, name: &str, _fn_type: Type<'gcc>, callconv: () /*llvm::CCallConv*/) -> RValue<'gcc> {
         // TODO(antoyo): use the fn_type parameter.
         let const_string = self.context.new_type::<u8>().make_pointer().make_pointer();
         let return_type = self.type_i32();
         let variadic = false;
         self.linkage.set(FunctionType::Exported);
-        let func = declare_raw_fn(self, name, () /*llvm::CCallConv*/, return_type, &[self.type_i32(), const_string], variadic);
+        let func = declare_raw_fn(self, name, callconv, return_type, &[self.type_i32(), const_string], variadic);
         // NOTE: it is needed to set the current_func here as well, because get_fn() is not called
         // for the main function.
         *self.current_func.borrow_mut() = Some(func);

compiler/rustc_codegen_llvm/src/abi.rs

@@ -398,23 +398,7 @@ impl<'ll, 'tcx> FnAbiLlvmExt<'ll, 'tcx> for FnAbi<'tcx, Ty<'tcx>> {
     }
 
     fn llvm_cconv(&self) -> llvm::CallConv {
-        match self.conv {
-            Conv::C | Conv::Rust | Conv::CCmseNonSecureCall => llvm::CCallConv,
-            Conv::RustCold => llvm::ColdCallConv,
-            Conv::AmdGpuKernel => llvm::AmdGpuKernel,
-            Conv::AvrInterrupt => llvm::AvrInterrupt,
-            Conv::AvrNonBlockingInterrupt => llvm::AvrNonBlockingInterrupt,
-            Conv::ArmAapcs => llvm::ArmAapcsCallConv,
-            Conv::Msp430Intr => llvm::Msp430Intr,
-            Conv::PtxKernel => llvm::PtxKernel,
-            Conv::X86Fastcall => llvm::X86FastcallCallConv,
-            Conv::X86Intr => llvm::X86_Intr,
-            Conv::X86Stdcall => llvm::X86StdcallCallConv,
-            Conv::X86ThisCall => llvm::X86_ThisCall,
-            Conv::X86VectorCall => llvm::X86_VectorCall,
-            Conv::X86_64SysV => llvm::X86_64_SysV,
-            Conv::X86_64Win64 => llvm::X86_64_Win64,
-        }
+        self.conv.into()
     }
 
     fn apply_attrs_llfn(&self, cx: &CodegenCx<'ll, 'tcx>, llfn: &'ll Value) {
@@ -596,3 +580,25 @@ impl<'tcx> AbiBuilderMethods<'tcx> for Builder<'_, '_, 'tcx> {
         llvm::get_param(self.llfn(), index as c_uint)
     }
 }
+
+impl From<Conv> for llvm::CallConv {
+    fn from(conv: Conv) -> Self {
+        match conv {
+            Conv::C | Conv::Rust | Conv::CCmseNonSecureCall => llvm::CCallConv,
+            Conv::RustCold => llvm::ColdCallConv,
+            Conv::AmdGpuKernel => llvm::AmdGpuKernel,
+            Conv::AvrInterrupt => llvm::AvrInterrupt,
+            Conv::AvrNonBlockingInterrupt => llvm::AvrNonBlockingInterrupt,
+            Conv::ArmAapcs => llvm::ArmAapcsCallConv,
+            Conv::Msp430Intr => llvm::Msp430Intr,
+            Conv::PtxKernel => llvm::PtxKernel,
+            Conv::X86Fastcall => llvm::X86FastcallCallConv,
+            Conv::X86Intr => llvm::X86_Intr,
+            Conv::X86Stdcall => llvm::X86StdcallCallConv,
+            Conv::X86ThisCall => llvm::X86_ThisCall,
+            Conv::X86VectorCall => llvm::X86_VectorCall,
+            Conv::X86_64SysV => llvm::X86_64_SysV,
+            Conv::X86_64Win64 => llvm::X86_64_Win64,
+        }
+    }
+}

compiler/rustc_codegen_llvm/src/context.rs

@@ -576,8 +576,14 @@ impl<'ll, 'tcx> MiscMethods<'tcx> for CodegenCx<'ll, 'tcx> {
     }
 
     fn declare_c_main(&self, fn_type: Self::Type) -> Option<Self::Function> {
-        if self.get_declared_value("main").is_none() {
-            Some(self.declare_cfn("main", llvm::UnnamedAddr::Global, fn_type))
+        let entry_name = self.sess().target.entry_name.as_ref();
+        if self.get_declared_value(entry_name).is_none() {
+            Some(self.declare_entry_fn(
+                entry_name,
+                self.sess().target.entry_abi.into(),
+                llvm::UnnamedAddr::Global,
+                fn_type,
+            ))
         } else {
             // If the symbol already exists, it is an error: for example, the user wrote
             // #[no_mangle] extern "C" fn main(..) {..}

compiler/rustc_codegen_llvm/src/declare.rs

@@ -90,6 +90,28 @@ impl<'ll, 'tcx> CodegenCx<'ll, 'tcx> {
         declare_raw_fn(self, name, llvm::CCallConv, unnamed, visibility, fn_type)
     }
 
+    /// Declare an entry Function
+    ///
+    /// The ABI of this function can change depending on the target (although for now the same as
+    /// `declare_cfn`)
+    ///
+    /// If there’s a value with the same name already declared, the function will
+    /// update the declaration and return existing Value instead.
+    pub fn declare_entry_fn(
+        &self,
+        name: &str,
+        callconv: llvm::CallConv,
+        unnamed: llvm::UnnamedAddr,
+        fn_type: &'ll Type,
+    ) -> &'ll Value {
+        let visibility = if self.tcx.sess.target.default_hidden_visibility {
+            llvm::Visibility::Hidden
+        } else {
+            llvm::Visibility::Default
+        };
+        declare_raw_fn(self, name, callconv, unnamed, visibility, fn_type)
+    }
+
     /// Declare a Rust function.
     ///
     /// If there’s a value with the same name already declared, the function will