Auto merge of #83042 - JohnTitor:rollup-s8efv94, r=JohnTitor

Rollup of 11 pull requests

Successful merges:

 - #80385 (Clarify what `Cell::replace` returns)
 - #82571 (Rustdoc Json: Add tests for Reexports, and improve jsondocck)
 - #82860 (Add `-Z unpretty` flag for the THIR)
 - #82950 (convert slice doc link to intra-doc links)
 - #82965 (Add spirv extension handling in compiletest)
 - #82966 (update MSYS2 link in README)
 - #82979 (Fix "run" button position in error index)
 - #83001 (Ignore Vim swap files)
 - #83003 (rustdoc: tweak the search index format)
 - #83013 (Adjust some `#[cfg]`s to take non-Unix non-Windows operating systems into account)
 - #83018 (Reintroduce accidentally deleted assertions.)

Failed merges:

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

Author: bors

Diff for: .gitignore

@@ -7,6 +7,8 @@
 # configure your local ignore list.
 # FIXME: This needs cleanup.
 *~
+*.swp
+*.swo
 .#*
 .DS_Store
 .cproject

Diff for: Cargo.lock

@@ -3870,13 +3870,15 @@ dependencies = [
  "rustc_metadata",
  "rustc_middle",
  "rustc_mir",
+ "rustc_mir_build",
  "rustc_parse",
  "rustc_plugin_impl",
  "rustc_save_analysis",
  "rustc_serialize",
  "rustc_session",
  "rustc_span",
  "rustc_target",
+ "rustc_typeck",
  "tracing",
  "tracing-subscriber",
  "tracing-tree",

Diff for: README.md

@@ -90,7 +90,7 @@ build.
 
 [MSYS2][msys2] can be used to easily build Rust on Windows:
 
-[msys2]: https://msys2.github.io/
+[msys2]: https://www.msys2.org/
 
 1. Grab the latest [MSYS2 installer][msys2] and go through the installer.
 

Diff for: compiler/rustc_codegen_ssa/src/back/link.rs

@@ -711,7 +711,7 @@ fn link_natively<'a, B: ArchiveBuilder<'a>>(
             status.signal() == Some(libc::SIGILL)
         }
 
-        #[cfg(windows)]
+        #[cfg(not(unix))]
         fn is_illegal_instruction(_status: &ExitStatus) -> bool {
             false
         }
@@ -1198,7 +1198,7 @@ fn exec_linker(
     flush_linked_file(&output, out_filename)?;
     return output;
 
-    #[cfg(unix)]
+    #[cfg(not(windows))]
     fn flush_linked_file(_: &io::Result<Output>, _: &Path) -> io::Result<()> {
         Ok(())
     }
@@ -1238,6 +1238,11 @@ fn exec_linker(
         err.raw_os_error() == Some(ERROR_FILENAME_EXCED_RANGE)
     }
 
+    #[cfg(not(any(unix, windows)))]
+    fn command_line_too_big(_: &io::Error) -> bool {
+        false
+    }
+
     struct Escape<'a> {
         arg: &'a str,
         is_like_msvc: bool,

Diff for: compiler/rustc_driver/Cargo.toml

@@ -34,6 +34,8 @@ rustc_interface = { path = "../rustc_interface" }
 rustc_serialize = { path = "../rustc_serialize" }
 rustc_ast = { path = "../rustc_ast" }
 rustc_span = { path = "../rustc_span" }
+rustc_mir_build = { path = "../rustc_mir_build" }
+rustc_typeck = { path = "../rustc_typeck" }
 
 [target.'cfg(windows)'.dependencies]
 winapi = { version = "0.3", features = ["consoleapi", "debugapi", "processenv"] }

Diff for: compiler/rustc_driver/src/pretty.rs

@@ -9,12 +9,14 @@ use rustc_hir_pretty as pprust_hir;
 use rustc_middle::hir::map as hir_map;
 use rustc_middle::ty::{self, TyCtxt};
 use rustc_mir::util::{write_mir_graphviz, write_mir_pretty};
+use rustc_mir_build::thir;
 use rustc_session::config::{Input, PpAstTreeMode, PpHirMode, PpMode, PpSourceMode};
 use rustc_session::Session;
 use rustc_span::symbol::Ident;
 use rustc_span::FileName;
 
 use std::cell::Cell;
+use std::fmt::Write;
 use std::path::Path;
 
 pub use self::PpMode::*;
@@ -469,6 +471,21 @@ pub fn print_after_hir_lowering<'tcx>(
             format!("{:#?}", krate)
         }),
 
+        ThirTree => {
+            let mut out = String::new();
+            abort_on_err(rustc_typeck::check_crate(tcx), tcx.sess);
+            debug!("pretty printing THIR tree");
+            for did in tcx.body_owners() {
+                let hir = tcx.hir();
+                let body = hir.body(hir.body_owned_by(hir.local_def_id_to_hir_id(did)));
+                let arena = thir::Arena::default();
+                let thir =
+                    thir::build_thir(tcx, ty::WithOptConstParam::unknown(did), &arena, &body.value);
+                let _ = writeln!(out, "{:?}:\n{:#?}\n", did, thir);
+            }
+            out
+        }
+
         _ => unreachable!(),
     };
 

Diff for: compiler/rustc_mir_build/src/build/mod.rs

@@ -1,7 +1,6 @@
 use crate::build;
 use crate::build::scope::DropKind;
-use crate::thir::cx::build_thir;
-use crate::thir::{Arena, BindingMode, Expr, LintLevel, Pat, PatKind};
+use crate::thir::{build_thir, Arena, BindingMode, Expr, LintLevel, Pat, PatKind};
 use rustc_attr::{self as attr, UnwindAttr};
 use rustc_errors::ErrorReported;
 use rustc_hir as hir;

Diff for: compiler/rustc_mir_build/src/lib.rs

@@ -20,7 +20,7 @@ extern crate rustc_middle;
 
 mod build;
 mod lints;
-mod thir;
+pub mod thir;
 
 use rustc_middle::ty::query::Providers;
 

Diff for: compiler/rustc_mir_build/src/thir/constant.rs

@@ -1,3 +1,4 @@
+use rustc_apfloat::Float;
 use rustc_ast as ast;
 use rustc_middle::mir::interpret::{
     Allocation, ConstValue, LitToConstError, LitToConstInput, Scalar,
@@ -61,20 +62,40 @@ fn parse_float<'tcx>(num: Symbol, fty: ty::FloatTy, neg: bool) -> Result<ConstVa
     use rustc_apfloat::ieee::{Double, Single};
     let scalar = match fty {
         ty::FloatTy::F32 => {
-            num.parse::<f32>().map_err(|_| ())?;
+            let rust_f = num.parse::<f32>().map_err(|_| ())?;
             let mut f = num.parse::<Single>().unwrap_or_else(|e| {
                 panic!("apfloat::ieee::Single failed to parse `{}`: {:?}", num, e)
             });
+            assert!(
+                u128::from(rust_f.to_bits()) == f.to_bits(),
+                "apfloat::ieee::Single gave different result for `{}`: \
+                 {}({:#x}) vs Rust's {}({:#x})",
+                rust_f,
+                f,
+                f.to_bits(),
+                Single::from_bits(rust_f.to_bits().into()),
+                rust_f.to_bits()
+            );
             if neg {
                 f = -f;
             }
             Scalar::from_f32(f)
         }
         ty::FloatTy::F64 => {
-            num.parse::<f64>().map_err(|_| ())?;
+            let rust_f = num.parse::<f64>().map_err(|_| ())?;
             let mut f = num.parse::<Double>().unwrap_or_else(|e| {
                 panic!("apfloat::ieee::Double failed to parse `{}`: {:?}", num, e)
             });
+            assert!(
+                u128::from(rust_f.to_bits()) == f.to_bits(),
+                "apfloat::ieee::Double gave different result for `{}`: \
+                 {}({:#x}) vs Rust's {}({:#x})",
+                rust_f,
+                f,
+                f.to_bits(),
+                Double::from_bits(rust_f.to_bits().into()),
+                rust_f.to_bits()
+            );
             if neg {
                 f = -f;
             }

Diff for: compiler/rustc_mir_build/src/thir/cx/mod.rs

@@ -14,7 +14,7 @@ use rustc_middle::middle::region;
 use rustc_middle::mir::interpret::{LitToConstError, LitToConstInput};
 use rustc_middle::ty::{self, Ty, TyCtxt};
 
-crate fn build_thir<'thir, 'tcx>(
+pub fn build_thir<'thir, 'tcx>(
     tcx: TyCtxt<'tcx>,
     owner_def: ty::WithOptConstParam<LocalDefId>,
     arena: &'thir Arena<'thir, 'tcx>,

Diff for: compiler/rustc_mir_build/src/thir/mod.rs

@@ -18,50 +18,51 @@ use rustc_target::abi::VariantIdx;
 use rustc_target::asm::InlineAsmRegOrRegClass;
 
 crate mod constant;
+
 crate mod cx;
+pub use cx::build_thir;
 
 crate mod pattern;
-crate use self::pattern::PatTyProj;
-crate use self::pattern::{BindingMode, FieldPat, Pat, PatKind, PatRange};
+pub use self::pattern::{Ascription, BindingMode, FieldPat, Pat, PatKind, PatRange, PatTyProj};
 
 mod arena;
-crate use arena::Arena;
+pub use arena::Arena;
 
 mod util;
 
 #[derive(Copy, Clone, Debug)]
-crate enum LintLevel {
+pub enum LintLevel {
     Inherited,
     Explicit(hir::HirId),
 }
 
 #[derive(Debug)]
-crate struct Block<'thir, 'tcx> {
-    crate targeted_by_break: bool,
-    crate region_scope: region::Scope,
-    crate opt_destruction_scope: Option<region::Scope>,
-    crate span: Span,
-    crate stmts: &'thir [Stmt<'thir, 'tcx>],
-    crate expr: Option<&'thir Expr<'thir, 'tcx>>,
-    crate safety_mode: BlockSafety,
+pub struct Block<'thir, 'tcx> {
+    pub targeted_by_break: bool,
+    pub region_scope: region::Scope,
+    pub opt_destruction_scope: Option<region::Scope>,
+    pub span: Span,
+    pub stmts: &'thir [Stmt<'thir, 'tcx>],
+    pub expr: Option<&'thir Expr<'thir, 'tcx>>,
+    pub safety_mode: BlockSafety,
 }
 
 #[derive(Copy, Clone, Debug)]
-crate enum BlockSafety {
+pub enum BlockSafety {
     Safe,
     ExplicitUnsafe(hir::HirId),
     PushUnsafe,
     PopUnsafe,
 }
 
 #[derive(Debug)]
-crate struct Stmt<'thir, 'tcx> {
-    crate kind: StmtKind<'thir, 'tcx>,
-    crate opt_destruction_scope: Option<region::Scope>,
+pub struct Stmt<'thir, 'tcx> {
+    pub kind: StmtKind<'thir, 'tcx>,
+    pub opt_destruction_scope: Option<region::Scope>,
 }
 
 #[derive(Debug)]
-crate enum StmtKind<'thir, 'tcx> {
+pub enum StmtKind<'thir, 'tcx> {
     Expr {
         /// scope for this statement; may be used as lifetime of temporaries
         scope: region::Scope,
@@ -111,23 +112,23 @@ rustc_data_structures::static_assert_size!(Expr<'_, '_>, 144);
 /// example, method calls and overloaded operators are absent: they are
 /// expected to be converted into `Expr::Call` instances.
 #[derive(Debug)]
-crate struct Expr<'thir, 'tcx> {
+pub struct Expr<'thir, 'tcx> {
     /// type of this expression
-    crate ty: Ty<'tcx>,
+    pub ty: Ty<'tcx>,
 
     /// lifetime of this expression if it should be spilled into a
     /// temporary; should be None only if in a constant context
-    crate temp_lifetime: Option<region::Scope>,
+    pub temp_lifetime: Option<region::Scope>,
 
     /// span of the expression in the source
-    crate span: Span,
+    pub span: Span,
 
     /// kind of expression
-    crate kind: ExprKind<'thir, 'tcx>,
+    pub kind: ExprKind<'thir, 'tcx>,
 }
 
 #[derive(Debug)]
-crate enum ExprKind<'thir, 'tcx> {
+pub enum ExprKind<'thir, 'tcx> {
     Scope {
         region_scope: region::Scope,
         lint_level: LintLevel,
@@ -316,41 +317,41 @@ crate enum ExprKind<'thir, 'tcx> {
 }
 
 #[derive(Debug)]
-crate struct FieldExpr<'thir, 'tcx> {
-    crate name: Field,
-    crate expr: &'thir Expr<'thir, 'tcx>,
+pub struct FieldExpr<'thir, 'tcx> {
+    pub name: Field,
+    pub expr: &'thir Expr<'thir, 'tcx>,
 }
 
 #[derive(Debug)]
-crate struct FruInfo<'thir, 'tcx> {
-    crate base: &'thir Expr<'thir, 'tcx>,
-    crate field_types: &'thir [Ty<'tcx>],
+pub struct FruInfo<'thir, 'tcx> {
+    pub base: &'thir Expr<'thir, 'tcx>,
+    pub field_types: &'thir [Ty<'tcx>],
 }
 
 #[derive(Debug)]
-crate struct Arm<'thir, 'tcx> {
-    crate pattern: Pat<'tcx>,
-    crate guard: Option<Guard<'thir, 'tcx>>,
-    crate body: &'thir Expr<'thir, 'tcx>,
-    crate lint_level: LintLevel,
-    crate scope: region::Scope,
-    crate span: Span,
+pub struct Arm<'thir, 'tcx> {
+    pub pattern: Pat<'tcx>,
+    pub guard: Option<Guard<'thir, 'tcx>>,
+    pub body: &'thir Expr<'thir, 'tcx>,
+    pub lint_level: LintLevel,
+    pub scope: region::Scope,
+    pub span: Span,
 }
 
 #[derive(Debug)]
-crate enum Guard<'thir, 'tcx> {
+pub enum Guard<'thir, 'tcx> {
     If(&'thir Expr<'thir, 'tcx>),
     IfLet(Pat<'tcx>, &'thir Expr<'thir, 'tcx>),
 }
 
 #[derive(Copy, Clone, Debug)]
-crate enum LogicalOp {
+pub enum LogicalOp {
     And,
     Or,
 }
 
 #[derive(Debug)]
-crate enum InlineAsmOperand<'thir, 'tcx> {
+pub enum InlineAsmOperand<'thir, 'tcx> {
     In {
         reg: InlineAsmRegOrRegClass,
         expr: &'thir Expr<'thir, 'tcx>,