Auto merge of rust-lang#2773 - RalfJung:rustup, r=RalfJung

Rustup

.github/ISSUE_TEMPLATE/ice.md

@@ -0,0 +1,49 @@
+---
+name: Internal Compiler Error
+about: Create a report for an internal compiler error in rustc.
+labels: C-bug, I-ICE, T-compiler
+---
+<!--
+Thank you for finding an Internal Compiler Error! 🧊  If possible, try to provide
+a minimal verifiable example. You can read "Rust Bug Minimization Patterns" for
+how to create smaller examples.
+http://blog.pnkfx.org/blog/2019/11/18/rust-bug-minimization-patterns/
+-->
+
+### Code
+
+```Rust
+<code>
+```
+
+
+### Meta
+<!--
+If you're using the stable version of the compiler, you should also check if the
+bug also exists in the beta or nightly versions.
+-->
+
+`rustc --version --verbose`:
+```
+<version>
+```
+
+### Error output
+
+```
+<output>
+```
+
+<!--
+Include a backtrace in the code block by setting `RUST_BACKTRACE=1` in your
+environment. E.g. `RUST_BACKTRACE=1 cargo build`.
+-->
+<details><summary><strong>Backtrace</strong></summary>
+<p>
+
+```
+<backtrace>
+```
+
+</p>
+</details>

.github/ISSUE_TEMPLATE/ice.yaml

@@ -1,5 +1,5 @@
-name: Internal Compiler Error
-description: Create a report for an internal compiler error in `rustc`
+name: Internal Compiler Error (Structured form)
+description: For now, you'll want to use the other ICE template, as GitHub forms have strict limits on the size of fields so backtraces cannot be pasted directly.
 labels: ["C-bug", "I-ICE", "T-compiler"]
 title: "[ICE]: "
 body:
@@ -79,4 +79,4 @@ body:
       label: Anything else?
       description: If you have more details you want to give us to reproduce this issue, please add it here
     validations:
-      required: false
+      required: false

Cargo.lock

@@ -342,7 +342,7 @@ dependencies = [
 
 [[package]]
 name = "cargo"
-version = "0.69.0"
+version = "0.70.0"
 dependencies = [
  "anyhow",
  "base64",

compiler/rustc_abi/src/lib.rs

@@ -1456,6 +1456,8 @@ pub enum PointerKind {
     UniqueOwned,
 }
 
+/// Note that this information is advisory only, and backends are free to ignore it.
+/// It can only be used to encode potential optimizations, but no critical information.
 #[derive(Copy, Clone, Debug)]
 pub struct PointeeInfo {
     pub size: Size,

compiler/rustc_ast/src/util/comments.rs

@@ -58,23 +58,24 @@ pub fn beautify_doc_string(data: Symbol, kind: CommentKind) -> Symbol {
         // In case we have doc comments like `/**` or `/*!`, we want to remove stars if they are
         // present. However, we first need to strip the empty lines so they don't get in the middle
         // when we try to compute the "horizontal trim".
-        let lines = if kind == CommentKind::Block {
-            // Whatever happens, we skip the first line.
-            let mut i = lines
-                .get(0)
-                .map(|l| if l.trim_start().starts_with('*') { 0 } else { 1 })
-                .unwrap_or(0);
-            let mut j = lines.len();
-
-            while i < j && lines[i].trim().is_empty() {
-                i += 1;
-            }
-            while j > i && lines[j - 1].trim().is_empty() {
-                j -= 1;
+        let lines = match kind {
+            CommentKind::Block => {
+                // Whatever happens, we skip the first line.
+                let mut i = lines
+                    .get(0)
+                    .map(|l| if l.trim_start().starts_with('*') { 0 } else { 1 })
+                    .unwrap_or(0);
+                let mut j = lines.len();
+
+                while i < j && lines[i].trim().is_empty() {
+                    i += 1;
+                }
+                while j > i && lines[j - 1].trim().is_empty() {
+                    j -= 1;
+                }
+                &lines[i..j]
             }
-            &lines[i..j]
-        } else {
-            lines
+            CommentKind::Line => lines,
         };
 
         for line in lines {

compiler/rustc_ast_pretty/src/pprust/state.rs

@@ -131,7 +131,7 @@ pub fn print_crate<'a>(
 
         // Currently, in Rust 2018 we don't have `extern crate std;` at the crate
         // root, so this is not needed, and actually breaks things.
-        if edition == Edition::Edition2015 {
+        if edition.rust_2015() {
             // `#![no_std]`
             let fake_attr = attr::mk_attr_word(g, ast::AttrStyle::Inner, sym::no_std, DUMMY_SP);
             s.print_attribute(&fake_attr);

compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs

@@ -344,7 +344,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
                     } else {
                         err.span_help(source_info.span, "try removing `&mut` here");
                     }
-                } else if decl.mutability == Mutability::Not {
+                } else if decl.mutability.is_not() {
                     if matches!(
                         decl.local_info,
                         Some(box LocalInfo::User(ClearCrossCrate::Set(BindingForm::ImplicitSelf(

compiler/rustc_borrowck/src/diagnostics/region_name.rs

@@ -187,6 +187,12 @@ impl Display for RegionName {
     }
 }
 
+impl rustc_errors::IntoDiagnosticArg for RegionName {
+    fn into_diagnostic_arg(self) -> rustc_errors::DiagnosticArgValue<'static> {
+        self.to_string().into_diagnostic_arg()
+    }
+}
+
 impl<'tcx> MirBorrowckCtxt<'_, 'tcx> {
     pub(crate) fn mir_def_id(&self) -> hir::def_id::LocalDefId {
         self.body.source.def_id().expect_local()

compiler/rustc_borrowck/src/nll.rs

@@ -369,6 +369,8 @@ pub(super) fn dump_mir_results<'tcx>(
     };
 }
 
+#[allow(rustc::diagnostic_outside_of_impl)]
+#[allow(rustc::untranslatable_diagnostic)]
 pub(super) fn dump_annotation<'tcx>(
     infcx: &InferCtxt<'tcx>,
     body: &Body<'tcx>,

compiler/rustc_borrowck/src/session_diagnostics.rs

@@ -1,4 +1,4 @@
-use rustc_errors::{IntoDiagnosticArg, MultiSpan};
+use rustc_errors::MultiSpan;
 use rustc_macros::{Diagnostic, LintDiagnostic, Subdiagnostic};
 use rustc_middle::ty::{GenericArg, Ty};
 use rustc_span::Span;
@@ -128,18 +128,6 @@ pub(crate) enum LifetimeReturnCategoryErr<'a> {
     },
 }
 
-impl IntoDiagnosticArg for &RegionName {
-    fn into_diagnostic_arg(self) -> rustc_errors::DiagnosticArgValue<'static> {
-        format!("{}", self).into_diagnostic_arg()
-    }
-}
-
-impl IntoDiagnosticArg for RegionName {
-    fn into_diagnostic_arg(self) -> rustc_errors::DiagnosticArgValue<'static> {
-        format!("{}", self).into_diagnostic_arg()
-    }
-}
-
 #[derive(Subdiagnostic)]
 pub(crate) enum RequireStaticErr {
     #[note(borrowck_used_impl_require_static)]

compiler/rustc_borrowck/src/type_check/canonical.rs

@@ -181,9 +181,6 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
         user_ty: ty::UserType<'tcx>,
         span: Span,
     ) {
-        // FIXME: Ideally MIR types are normalized, but this is not always true.
-        let mir_ty = self.normalize(mir_ty, Locations::All(span));
-
         self.fully_perform_op(
             Locations::All(span),
             ConstraintCategory::Boring,
@@ -217,7 +214,9 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
             return;
         }
 
+        // FIXME: Ideally MIR types are normalized, but this is not always true.
         let mir_ty = self.normalize(mir_ty, Locations::All(span));
+
         let cause = ObligationCause::dummy_with_span(span);
         let param_env = self.param_env;
         let op = |infcx: &'_ _| {

compiler/rustc_borrowck/src/type_check/mod.rs

@@ -2028,7 +2028,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
                             }
                         };
 
-                        if ty_to_mut == Mutability::Mut && ty_mut == Mutability::Not {
+                        if ty_to_mut.is_mut() && ty_mut.is_not() {
                             span_mirbug!(
                                 self,
                                 rvalue,

compiler/rustc_codegen_gcc/src/lib.rs

@@ -200,6 +200,7 @@ unsafe impl Sync for GccContext {}
 impl WriteBackendMethods for GccCodegenBackend {
     type Module = GccContext;
     type TargetMachine = ();
+    type TargetMachineError = ();
     type ModuleBuffer = ModuleBuffer;
     type ThinData = ();
     type ThinBuffer = ThinBuffer;

compiler/rustc_codegen_llvm/src/back/lto.rs

@@ -1,5 +1,7 @@
 use crate::back::write::{self, save_temp_bitcode, DiagnosticHandlers};
-use crate::errors::DynamicLinkingWithLTO;
+use crate::errors::{
+    DynamicLinkingWithLTO, LlvmError, LtoBitcodeFromRlib, LtoDisallowed, LtoDylib,
+};
 use crate::llvm::{self, build_string};
 use crate::{LlvmCodegenBackend, ModuleLlvm};
 use object::read::archive::ArchiveFile;
@@ -77,15 +79,12 @@ fn prepare_lto(
         // Make sure we actually can run LTO
         for crate_type in cgcx.crate_types.iter() {
             if !crate_type_allows_lto(*crate_type) {
-                let e = diag_handler.fatal(
-                    "lto can only be run for executables, cdylibs and \
-                                            static library outputs",
-                );
-                return Err(e);
+                diag_handler.emit_err(LtoDisallowed);
+                return Err(FatalError);
             } else if *crate_type == CrateType::Dylib {
                 if !cgcx.opts.unstable_opts.dylib_lto {
-                    return Err(diag_handler
-                        .fatal("lto cannot be used for `dylib` crate type without `-Zdylib-lto`"));
+                    diag_handler.emit_err(LtoDylib);
+                    return Err(FatalError);
                 }
             }
         }
@@ -127,7 +126,10 @@ fn prepare_lto(
                         let module = SerializedModule::FromRlib(data.to_vec());
                         upstream_modules.push((module, CString::new(name).unwrap()));
                     }
-                    Err(msg) => return Err(diag_handler.fatal(&msg)),
+                    Err(e) => {
+                        diag_handler.emit_err(e);
+                        return Err(FatalError);
+                    }
                 }
             }
         }
@@ -140,7 +142,7 @@ fn prepare_lto(
     Ok((symbols_below_threshold, upstream_modules))
 }
 
-fn get_bitcode_slice_from_object_data(obj: &[u8]) -> Result<&[u8], String> {
+fn get_bitcode_slice_from_object_data(obj: &[u8]) -> Result<&[u8], LtoBitcodeFromRlib> {
     let mut len = 0;
     let data =
         unsafe { llvm::LLVMRustGetBitcodeSliceFromObjectData(obj.as_ptr(), obj.len(), &mut len) };
@@ -155,8 +157,9 @@ fn get_bitcode_slice_from_object_data(obj: &[u8]) -> Result<&[u8], String> {
         Ok(bc)
     } else {
         assert!(len == 0);
-        let msg = llvm::last_error().unwrap_or_else(|| "unknown LLVM error".to_string());
-        Err(format!("failed to get bitcode from object file for LTO ({})", msg))
+        Err(LtoBitcodeFromRlib {
+            llvm_err: llvm::last_error().unwrap_or_else(|| "unknown LLVM error".to_string()),
+        })
     }
 }
 
@@ -328,10 +331,9 @@ fn fat_lto(
                 });
             info!("linking {:?}", name);
             let data = bc_decoded.data();
-            linker.add(data).map_err(|()| {
-                let msg = format!("failed to load bitcode of module {:?}", name);
-                write::llvm_err(diag_handler, &msg)
-            })?;
+            linker
+                .add(data)
+                .map_err(|()| write::llvm_err(diag_handler, LlvmError::LoadBitcode { name }))?;
             serialized_bitcode.push(bc_decoded);
         }
         drop(linker);
@@ -489,7 +491,7 @@ fn thin_lto(
             symbols_below_threshold.as_ptr(),
             symbols_below_threshold.len() as u32,
         )
-        .ok_or_else(|| write::llvm_err(diag_handler, "failed to prepare thin LTO context"))?;
+        .ok_or_else(|| write::llvm_err(diag_handler, LlvmError::PrepareThinLtoContext))?;
 
         let data = ThinData(data);
 
@@ -562,8 +564,7 @@ fn thin_lto(
         // session, overwriting the previous serialized data (if any).
         if let Some(path) = key_map_path {
             if let Err(err) = curr_key_map.save_to_file(&path) {
-                let msg = format!("Error while writing ThinLTO key data: {}", err);
-                return Err(write::llvm_err(diag_handler, &msg));
+                return Err(write::llvm_err(diag_handler, LlvmError::WriteThinLtoKey { err }));
             }
         }
 
@@ -689,8 +690,7 @@ pub unsafe fn optimize_thin_module(
 
     let module_name = &thin_module.shared.module_names[thin_module.idx];
     let tm_factory_config = TargetMachineFactoryConfig::new(cgcx, module_name.to_str().unwrap());
-    let tm =
-        (cgcx.tm_factory)(tm_factory_config).map_err(|e| write::llvm_err(&diag_handler, &e))?;
+    let tm = (cgcx.tm_factory)(tm_factory_config).map_err(|e| write::llvm_err(&diag_handler, e))?;
 
     // Right now the implementation we've got only works over serialized
     // modules, so we create a fresh new LLVM context and parse the module
@@ -717,8 +717,7 @@ pub unsafe fn optimize_thin_module(
         let mut cu2 = ptr::null_mut();
         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));
+            return Err(write::llvm_err(&diag_handler, LlvmError::MultipleSourceDiCompileUnit));
         }
 
         // Up next comes the per-module local analyses that we do for Thin LTO.
@@ -733,8 +732,7 @@ pub unsafe fn optimize_thin_module(
             let _timer =
                 cgcx.prof.generic_activity_with_arg("LLVM_thin_lto_rename", thin_module.name());
             if !llvm::LLVMRustPrepareThinLTORename(thin_module.shared.data.0, llmod, target) {
-                let msg = "failed to prepare thin LTO module";
-                return Err(write::llvm_err(&diag_handler, msg));
+                return Err(write::llvm_err(&diag_handler, LlvmError::PrepareThinLtoModule));
             }
             save_temp_bitcode(cgcx, &module, "thin-lto-after-rename");
         }
@@ -744,8 +742,7 @@ pub unsafe fn optimize_thin_module(
                 .prof
                 .generic_activity_with_arg("LLVM_thin_lto_resolve_weak", thin_module.name());
             if !llvm::LLVMRustPrepareThinLTOResolveWeak(thin_module.shared.data.0, llmod) {
-                let msg = "failed to prepare thin LTO module";
-                return Err(write::llvm_err(&diag_handler, msg));
+                return Err(write::llvm_err(&diag_handler, LlvmError::PrepareThinLtoModule));
             }
             save_temp_bitcode(cgcx, &module, "thin-lto-after-resolve");
         }
@@ -755,8 +752,7 @@ pub unsafe fn optimize_thin_module(
                 .prof
                 .generic_activity_with_arg("LLVM_thin_lto_internalize", thin_module.name());
             if !llvm::LLVMRustPrepareThinLTOInternalize(thin_module.shared.data.0, llmod) {
-                let msg = "failed to prepare thin LTO module";
-                return Err(write::llvm_err(&diag_handler, msg));
+                return Err(write::llvm_err(&diag_handler, LlvmError::PrepareThinLtoModule));
             }
             save_temp_bitcode(cgcx, &module, "thin-lto-after-internalize");
         }
@@ -765,8 +761,7 @@ pub unsafe fn optimize_thin_module(
             let _timer =
                 cgcx.prof.generic_activity_with_arg("LLVM_thin_lto_import", thin_module.name());
             if !llvm::LLVMRustPrepareThinLTOImport(thin_module.shared.data.0, llmod, target) {
-                let msg = "failed to prepare thin LTO module";
-                return Err(write::llvm_err(&diag_handler, msg));
+                return Err(write::llvm_err(&diag_handler, LlvmError::PrepareThinLtoModule));
             }
             save_temp_bitcode(cgcx, &module, "thin-lto-after-import");
         }
@@ -886,11 +881,7 @@ pub fn parse_module<'a>(
     diag_handler: &Handler,
 ) -> Result<&'a llvm::Module, FatalError> {
     unsafe {
-        llvm::LLVMRustParseBitcodeForLTO(cx, data.as_ptr(), data.len(), name.as_ptr()).ok_or_else(
-            || {
-                let msg = "failed to parse bitcode for LTO module";
-                write::llvm_err(diag_handler, msg)
-            },
-        )
+        llvm::LLVMRustParseBitcodeForLTO(cx, data.as_ptr(), data.len(), name.as_ptr())
+            .ok_or_else(|| write::llvm_err(diag_handler, LlvmError::ParseBitcode))
     }
 }