Auto merge of #64246 - Centril:rollup-zey4o09, r=Centril

Rollup of 10 pull requests

Successful merges:

 - #63919 (Use hygiene for AST passes)
 - #63927 (Filter linkcheck spurious failure)
 - #64149 (rustc_codegen_llvm: give names to non-alloca variable values.)
 - #64192 (Bail out when encountering likely missing turbofish in parser)
 - #64231 (Move the HIR CFG to `rustc_ast_borrowck`)
 - #64233 (Correct pluralisation of various diagnostic messages)
 - #64236 (reduce visibility)
 - #64240 (Include compiler-rt in the source tarball)
 - #64241 ([doc] Added more prereqs and note about default directory)
 - #64243 (Move injection of attributes from command line to `libsyntax_ext`)

Failed merges:

r? @ghost

README.md

@@ -32,6 +32,7 @@ or reading the [rustc guide][rustcguidebuild].
    * `cmake` 3.4.3 or later
    * `curl`
    * `git`
+   * `ssl` which comes in `libssl-dev` or `openssl-devel`
 
 2. Clone the [source] with `git`:
 
@@ -56,6 +57,8 @@ or reading the [rustc guide][rustcguidebuild].
     an installation (using `./x.py install`) that you set the `prefix` value
     in the `[install]` section to a directory that you have write permissions.
 
+    Create install directory if you are not installing in default directory
+
 4. Build and install:
 
     ```sh

src/bootstrap/dist.rs

@@ -808,6 +808,7 @@ fn copy_src_dirs(builder: &Builder<'_>, src_dirs: &[&str], exclude_dirs: &[&str]
             "llvm-project/lld", "llvm-project\\lld",
             "llvm-project/lldb", "llvm-project\\lldb",
             "llvm-project/llvm", "llvm-project\\llvm",
+            "llvm-project/compiler-rt", "llvm-project\\compiler-rt",
         ];
         if spath.contains("llvm-project") && !spath.ends_with("llvm-project")
             && !LLVM_PROJECTS.iter().any(|path| spath.contains(path))

src/librustc/ich/impls_syntax.rs

@@ -390,9 +390,17 @@ impl_stable_hash_for!(struct ::syntax_pos::hygiene::ExpnData {
 impl_stable_hash_for!(enum ::syntax_pos::hygiene::ExpnKind {
     Root,
     Macro(kind, descr),
+    AstPass(kind),
     Desugaring(kind)
 });
 
+impl_stable_hash_for!(enum ::syntax_pos::hygiene::AstPass {
+    StdImports,
+    TestHarness,
+    ProcMacroHarness,
+    PluginMacroDefs,
+});
+
 impl_stable_hash_for!(enum ::syntax_pos::hygiene::DesugaringKind {
     CondTemporary,
     Async,

src/librustc/lib.rs

@@ -97,7 +97,6 @@ pub mod query;
 
 #[macro_use]
 pub mod arena;
-pub mod cfg;
 pub mod dep_graph;
 pub mod hir;
 pub mod ich;

src/librustc/lint/mod.rs

@@ -646,6 +646,30 @@ pub fn struct_lint_level<'a>(sess: &'a Session,
         (Level::Forbid, None) => sess.struct_err(msg),
     };
 
+    // Check for future incompatibility lints and issue a stronger warning.
+    let lints = sess.lint_store.borrow();
+    let lint_id = LintId::of(lint);
+    let future_incompatible = lints.future_incompatible(lint_id);
+
+    // If this code originates in a foreign macro, aka something that this crate
+    // did not itself author, then it's likely that there's nothing this crate
+    // can do about it. We probably want to skip the lint entirely.
+    if err.span.primary_spans().iter().any(|s| in_external_macro(sess, *s)) {
+        // Any suggestions made here are likely to be incorrect, so anything we
+        // emit shouldn't be automatically fixed by rustfix.
+        err.allow_suggestions(false);
+
+        // If this is a future incompatible lint it'll become a hard error, so
+        // we have to emit *something*. Also allow lints to whitelist themselves
+        // on a case-by-case basis for emission in a foreign macro.
+        if future_incompatible.is_none() && !lint.report_in_external_macro {
+            err.cancel();
+            // Don't continue further, since we don't want to have
+            // `diag_span_note_once` called for a diagnostic that isn't emitted.
+            return err;
+        }
+    }
+
     let name = lint.name_lower();
     match src {
         LintSource::Default => {
@@ -695,10 +719,6 @@ pub fn struct_lint_level<'a>(sess: &'a Session,
 
     err.code(DiagnosticId::Lint(name));
 
-    // Check for future incompatibility lints and issue a stronger warning.
-    let lints = sess.lint_store.borrow();
-    let lint_id = LintId::of(lint);
-    let future_incompatible = lints.future_incompatible(lint_id);
     if let Some(future_incompatible) = future_incompatible {
         const STANDARD_MESSAGE: &str =
             "this was previously accepted by the compiler but is being phased out; \
@@ -723,22 +743,6 @@ pub fn struct_lint_level<'a>(sess: &'a Session,
         err.note(&citation);
     }
 
-    // If this code originates in a foreign macro, aka something that this crate
-    // did not itself author, then it's likely that there's nothing this crate
-    // can do about it. We probably want to skip the lint entirely.
-    if err.span.primary_spans().iter().any(|s| in_external_macro(sess, *s)) {
-        // Any suggestions made here are likely to be incorrect, so anything we
-        // emit shouldn't be automatically fixed by rustfix.
-        err.allow_suggestions(false);
-
-        // If this is a future incompatible lint it'll become a hard error, so
-        // we have to emit *something*. Also allow lints to whitelist themselves
-        // on a case-by-case basis for emission in a foreign macro.
-        if future_incompatible.is_none() && !lint.report_in_external_macro {
-            err.cancel()
-        }
-    }
-
     return err
 }
 
@@ -868,7 +872,7 @@ pub fn in_external_macro(sess: &Session, span: Span) -> bool {
     let expn_data = span.ctxt().outer_expn_data();
     match expn_data.kind {
         ExpnKind::Root | ExpnKind::Desugaring(DesugaringKind::ForLoop) => false,
-        ExpnKind::Desugaring(_) => true, // well, it's "external"
+        ExpnKind::AstPass(_) | ExpnKind::Desugaring(_) => true, // well, it's "external"
         ExpnKind::Macro(MacroKind::Bang, _) => {
             if expn_data.def_site.is_dummy() {
                 // dummy span for the def_site means it's an external macro

src/librustc/ty/error.rs

@@ -200,7 +200,9 @@ impl<'tcx> ty::TyS<'tcx> {
             ty::Array(_, n) => {
                 let n = tcx.lift_to_global(&n).unwrap();
                 match n.try_eval_usize(tcx, ty::ParamEnv::empty()) {
-                    Some(n) => format!("array of {} elements", n).into(),
+                    Some(n) => {
+                        format!("array of {} element{}", n, if n != 1 { "s" } else { "" }).into()
+                    }
                     None => "array".into(),
                 }
             }

src/librustc_ast_borrowck/borrowck/mod.rs

@@ -9,7 +9,6 @@ use InteriorKind::*;
 
 use rustc::hir::HirId;
 use rustc::hir::Node;
-use rustc::cfg;
 use rustc::middle::borrowck::{BorrowCheckResult, SignalledError};
 use rustc::hir::def_id::{DefId, LocalDefId};
 use rustc::middle::mem_categorization as mc;
@@ -28,6 +27,7 @@ use log::debug;
 
 use rustc::hir;
 
+use crate::cfg;
 use crate::dataflow::{DataFlowContext, BitwiseOperator, DataFlowOperator, KillFrom};
 
 pub mod check_loans;

src/librustc_ast_borrowck/borrowck/move_data.rs

@@ -4,7 +4,7 @@
 use crate::dataflow::{DataFlowContext, BitwiseOperator, DataFlowOperator, KillFrom};
 
 use crate::borrowck::*;
-use rustc::cfg;
+use crate::cfg;
 use rustc::ty::{self, TyCtxt};
 use rustc::util::nodemap::FxHashMap;
 

src/librustc/cfg/construct.rs → src/librustc_ast_borrowck/cfg/construct.rs

@@ -1,11 +1,11 @@
 use crate::cfg::*;
-use crate::middle::region;
 use rustc_data_structures::graph::implementation as graph;
-use crate::ty::{self, TyCtxt};
+use rustc::middle::region;
+use rustc::ty::{self, TyCtxt};
 
-use crate::hir::{self, PatKind};
-use crate::hir::def_id::DefId;
-use crate::hir::ptr::P;
+use rustc::hir::{self, PatKind};
+use rustc::hir::def_id::DefId;
+use rustc::hir::ptr::P;
 
 struct CFGBuilder<'a, 'tcx> {
     tcx: TyCtxt<'tcx>,
@@ -30,7 +30,7 @@ struct LoopScope {
     break_index: CFGIndex,    // where to go on a `break`
 }
 
-pub fn construct(tcx: TyCtxt<'_>, body: &hir::Body) -> CFG {
+pub(super) fn construct(tcx: TyCtxt<'_>, body: &hir::Body) -> CFG {
     let mut graph = graph::Graph::new();
     let entry = graph.add_node(CFGNodeData::Entry);
 

src/librustc/cfg/graphviz.rs → src/librustc_ast_borrowck/cfg/graphviz.rs

@@ -1,15 +1,12 @@
 /// This module provides linkage between rustc::middle::graph and
 /// libgraphviz traits.
 
-// For clarity, rename the graphviz crate locally to dot.
-use graphviz as dot;
-
 use crate::cfg;
-use crate::hir;
-use crate::ty::TyCtxt;
+use rustc::hir;
+use rustc::ty::TyCtxt;
 
-pub type Node<'a> = (cfg::CFGIndex, &'a cfg::CFGNode);
-pub type Edge<'a> = &'a cfg::CFGEdge;
+pub(crate) type Node<'a> = (cfg::CFGIndex, &'a cfg::CFGNode);
+pub(crate) type Edge<'a> = &'a cfg::CFGEdge;
 
 pub struct LabelledCFG<'a, 'tcx> {
     pub tcx: TyCtxt<'tcx>,

src/librustc/cfg/mod.rs → src/librustc_ast_borrowck/cfg/mod.rs

@@ -2,18 +2,18 @@
 //! Uses `Graph` as the underlying representation.
 
 use rustc_data_structures::graph::implementation as graph;
-use crate::ty::TyCtxt;
-use crate::hir;
-use crate::hir::def_id::DefId;
+use rustc::ty::TyCtxt;
+use rustc::hir;
+use rustc::hir::def_id::DefId;
 
 mod construct;
 pub mod graphviz;
 
 pub struct CFG {
-    pub owner_def_id: DefId,
-    pub graph: CFGGraph,
-    pub entry: CFGIndex,
-    pub exit: CFGIndex,
+    owner_def_id: DefId,
+    pub(crate) graph: CFGGraph,
+    pub(crate) entry: CFGIndex,
+    exit: CFGIndex,
 }
 
 #[derive(Copy, Clone, Debug, PartialEq)]
@@ -26,7 +26,7 @@ pub enum CFGNodeData {
 }
 
 impl CFGNodeData {
-    pub fn id(&self) -> hir::ItemLocalId {
+    pub(crate) fn id(&self) -> hir::ItemLocalId {
         if let CFGNodeData::AST(id) = *self {
             id
         } else {
@@ -37,24 +37,19 @@ impl CFGNodeData {
 
 #[derive(Debug)]
 pub struct CFGEdgeData {
-    pub exiting_scopes: Vec<hir::ItemLocalId>
+    pub(crate) exiting_scopes: Vec<hir::ItemLocalId>
 }
 
-pub type CFGIndex = graph::NodeIndex;
+pub(crate) type CFGIndex = graph::NodeIndex;
 
-pub type CFGGraph = graph::Graph<CFGNodeData, CFGEdgeData>;
+pub(crate) type CFGGraph = graph::Graph<CFGNodeData, CFGEdgeData>;
 
-pub type CFGNode = graph::Node<CFGNodeData>;
+pub(crate) type CFGNode = graph::Node<CFGNodeData>;
 
-pub type CFGEdge = graph::Edge<CFGEdgeData>;
+pub(crate) type CFGEdge = graph::Edge<CFGEdgeData>;
 
 impl CFG {
     pub fn new(tcx: TyCtxt<'_>, body: &hir::Body) -> CFG {
         construct::construct(tcx, body)
     }
-
-    pub fn node_is_reachable(&self, id: hir::ItemLocalId) -> bool {
-        self.graph.depth_traverse(self.entry, graph::OUTGOING)
-                  .any(|idx| self.graph.node_data(idx).id() == id)
-    }
 }

src/librustc_ast_borrowck/dataflow.rs

@@ -3,9 +3,7 @@
 //! and thus uses bitvectors. Your job is simply to specify the so-called
 //! GEN and KILL bits for each expression.
 
-use rustc::cfg;
-use rustc::cfg::CFGIndex;
-use rustc::ty::TyCtxt;
+use crate::cfg::{self, CFGIndex};
 use std::mem;
 use std::usize;
 use log::debug;
@@ -16,6 +14,7 @@ use rustc::util::nodemap::FxHashMap;
 use rustc::hir;
 use rustc::hir::intravisit;
 use rustc::hir::print as pprust;
+use rustc::ty::TyCtxt;
 
 #[derive(Copy, Clone, Debug)]
 pub enum EntryOrExit {

src/librustc_ast_borrowck/graphviz.rs

@@ -4,13 +4,12 @@
 
 pub use Variant::*;
 
-pub use rustc::cfg::graphviz::{Node, Edge};
-use rustc::cfg::graphviz as cfg_dot;
-
+pub(crate) use crate::cfg::graphviz::{Node, Edge};
+use crate::cfg::graphviz as cfg_dot;
+use crate::cfg::CFGIndex;
 use crate::borrowck::{self, BorrowckCtxt, LoanPath};
 use crate::dataflow::{DataFlowOperator, DataFlowContext, EntryOrExit};
 use log::debug;
-use rustc::cfg::CFGIndex;
 use std::rc::Rc;
 
 #[derive(Debug, Copy, Clone)]

src/librustc_ast_borrowck/lib.rs

@@ -18,5 +18,6 @@ mod borrowck;
 pub mod graphviz;
 
 mod dataflow;
+pub mod cfg;
 
 pub use borrowck::provide;

src/librustc_codegen_llvm/debuginfo/mod.rs

@@ -32,7 +32,7 @@ use rustc_codegen_ssa::debuginfo::{FunctionDebugContext, MirDebugScope, Variable
 
 use libc::c_uint;
 use std::cell::RefCell;
-use std::ffi::CString;
+use std::ffi::{CStr, CString};
 
 use syntax_pos::{self, Span, Pos};
 use syntax::ast;
@@ -224,8 +224,37 @@ impl DebugInfoBuilderMethods<'tcx> for Builder<'a, 'll, 'tcx> {
         gdb::insert_reference_to_gdb_debug_scripts_section_global(self)
     }
 
-    fn set_value_name(&mut self, value: &'ll Value, name: &str) {
-        let cname = SmallCStr::new(name);
+    fn set_var_name(&mut self, value: &'ll Value, name: impl ToString) {
+        // Avoid wasting time if LLVM value names aren't even enabled.
+        if self.sess().fewer_names() {
+            return;
+        }
+
+        // Only function parameters and instructions are local to a function,
+        // don't change the name of anything else (e.g. globals).
+        let param_or_inst = unsafe {
+            llvm::LLVMIsAArgument(value).is_some() ||
+            llvm::LLVMIsAInstruction(value).is_some()
+        };
+        if !param_or_inst {
+            return;
+        }
+
+        let old_name = unsafe {
+            CStr::from_ptr(llvm::LLVMGetValueName(value))
+        };
+        match old_name.to_str() {
+            Ok("") => {}
+            Ok(_) => {
+                // Avoid replacing the name if it already exists.
+                // While we could combine the names somehow, it'd
+                // get noisy quick, and the usefulness is dubious.
+                return;
+            }
+            Err(_) => return,
+        }
+
+        let cname = CString::new(name.to_string()).unwrap();
         unsafe {
             llvm::LLVMSetValueName(value, cname.as_ptr());
         }

src/librustc_codegen_llvm/llvm/ffi.rs

@@ -806,6 +806,7 @@ extern "C" {
     pub fn LLVMRustRemoveFunctionAttributes(Fn: &Value, index: c_uint, attr: Attribute);
 
     // Operations on parameters
+    pub fn LLVMIsAArgument(Val: &Value) -> Option<&Value>;
     pub fn LLVMCountParams(Fn: &Value) -> c_uint;
     pub fn LLVMGetParam(Fn: &Value, Index: c_uint) -> &Value;
 
@@ -818,6 +819,7 @@ extern "C" {
     pub fn LLVMDeleteBasicBlock(BB: &BasicBlock);
 
     // Operations on instructions
+    pub fn LLVMIsAInstruction(Val: &Value) -> Option<&Value>;
     pub fn LLVMGetFirstBasicBlock(Fn: &Value) -> &BasicBlock;
 
     // Operations on call sites