Auto merge of #66180 - Centril:rollup-c1ji943, r=Centril

Rollup of 5 pull requests

Successful merges:

 - #59789 (Revert two unapproved changes to rustc_typeck.)
 - #65752 (Use structured suggestions for missing associated items)
 - #65884 (syntax: ABI-oblivious grammar)
 - #65974 (A scheme for more macro-matcher friendly pre-expansion gating)
 - #66017 (Add future incompatibility lint for `array.into_iter()`)

Failed merges:

 - #66056 (rustc_metadata: Some reorganization of the module structure)

r? @ghost

Author: bors

Cargo.lock

@@ -3762,7 +3762,6 @@ dependencies = [
  "rustc",
  "rustc_codegen_utils",
  "rustc_data_structures",
- "rustc_target",
  "serde_json",
  "syntax",
  "syntax_pos",
@@ -4362,7 +4361,6 @@ dependencies = [
  "rustc_errors",
  "rustc_index",
  "rustc_lexer",
- "rustc_target",
  "scoped-tls",
  "serialize",
  "smallvec 1.0.0",
@@ -4380,7 +4378,6 @@ dependencies = [
  "rustc_errors",
  "rustc_index",
  "rustc_lexer",
- "rustc_target",
  "scoped-tls",
  "serialize",
  "smallvec 1.0.0",

src/libcore/iter/traits/collect.rs

@@ -205,6 +205,7 @@ pub trait FromIterator<A>: Sized {
 ///         .collect()
 /// }
 /// ```
+#[rustc_diagnostic_item = "IntoIterator"]
 #[stable(feature = "rust1", since = "1.0.0")]
 pub trait IntoIterator {
     /// The type of the elements being iterated over.

src/librustc/error_codes.rs

@@ -2336,6 +2336,7 @@ the future, [RFC 2091] prohibits their implementation without a follow-up RFC.
     E0657, // `impl Trait` can only capture lifetimes bound at the fn level
     E0687, // in-band lifetimes cannot be used in `fn`/`Fn` syntax
     E0688, // in-band lifetimes cannot be mixed with explicit lifetime binders
+    E0703, // invalid ABI
 //  E0707, // multiple elided lifetimes used in arguments of `async fn`
     E0708, // `async` non-`move` closures with parameters are not currently
            // supported

src/librustc/hir/lowering.rs

@@ -1216,7 +1216,7 @@ impl<'a> LoweringContext<'a> {
                                     ImplTraitContext::disallowed(),
                                 ),
                                 unsafety: this.lower_unsafety(f.unsafety),
-                                abi: f.abi,
+                                abi: this.lower_abi(f.abi),
                                 decl: this.lower_fn_decl(&f.decl, None, false, None),
                                 param_names: this.lower_fn_params_to_names(&f.decl),
                             }))

src/librustc/hir/lowering/item.rs

@@ -12,6 +12,7 @@ use crate::hir::def::{Res, DefKind};
 use crate::util::nodemap::NodeMap;
 
 use rustc_data_structures::thin_vec::ThinVec;
+use rustc_target::spec::abi;
 
 use std::collections::BTreeSet;
 use smallvec::SmallVec;
@@ -735,7 +736,7 @@ impl LoweringContext<'_> {
 
     fn lower_foreign_mod(&mut self, fm: &ForeignMod) -> hir::ForeignMod {
         hir::ForeignMod {
-            abi: fm.abi,
+            abi: self.lower_abi(fm.abi),
             items: fm.items
                 .iter()
                 .map(|x| self.lower_foreign_item(x))
@@ -1291,10 +1292,30 @@ impl LoweringContext<'_> {
             unsafety: self.lower_unsafety(h.unsafety),
             asyncness: self.lower_asyncness(h.asyncness.node),
             constness: self.lower_constness(h.constness),
-            abi: h.abi,
+            abi: self.lower_abi(h.abi),
         }
     }
 
+    pub(super) fn lower_abi(&mut self, abi: Abi) -> abi::Abi {
+        abi::lookup(&abi.symbol.as_str()).unwrap_or_else(|| {
+            self.error_on_invalid_abi(abi);
+            abi::Abi::Rust
+        })
+    }
+
+    fn error_on_invalid_abi(&self, abi: Abi) {
+        struct_span_err!(
+            self.sess,
+            abi.span,
+            E0703,
+            "invalid ABI: found `{}`",
+            abi.symbol
+        )
+        .span_label(abi.span, "invalid ABI")
+        .help(&format!("valid ABIs: {}", abi::all_names().join(", ")))
+        .emit();
+    }
+
     pub(super) fn lower_unsafety(&mut self, u: Unsafety) -> hir::Unsafety {
         match u {
             Unsafety::Unsafe => hir::Unsafety::Unsafe,

src/librustc/hir/mod.rs

@@ -1075,6 +1075,13 @@ impl Mutability {
             MutImmutable => MutMutable,
         }
     }
+
+    pub fn prefix_str(&self) -> &'static str {
+        match self {
+            MutMutable => "mut ",
+            MutImmutable => "",
+        }
+    }
 }
 
 #[derive(Copy, Clone, PartialEq, RustcEncodable, RustcDecodable, Debug, HashStable)]
@@ -2184,6 +2191,15 @@ pub enum Unsafety {
     Normal,
 }
 
+impl Unsafety {
+    pub fn prefix_str(&self) -> &'static str {
+        match self {
+            Unsafety::Unsafe => "unsafe ",
+            Unsafety::Normal => "",
+        }
+    }
+}
+
 #[derive(Copy, Clone, PartialEq, RustcEncodable, RustcDecodable, Debug, HashStable)]
 pub enum Constness {
     Const,

src/librustc/hir/print.rs

@@ -1734,9 +1734,7 @@ impl<'a> State<'a> {
                     _ => false,
                 };
                 self.s.word("&");
-                if mutbl == hir::MutMutable {
-                    self.s.word("mut ");
-                }
+                self.s.word(mutbl.prefix_str());
                 if is_range_inner {
                     self.popen();
                 }

src/librustc/ich/impls_syntax.rs

@@ -124,7 +124,6 @@ for ::syntax::attr::StabilityLevel {
 
 impl_stable_hash_for!(struct ::syntax::attr::RustcDeprecation { since, reason, suggestion });
 
-
 impl_stable_hash_for!(enum ::syntax::attr::IntType {
     SignedInt(int_ty),
     UnsignedInt(uint_ty)
@@ -136,6 +135,11 @@ impl_stable_hash_for!(enum ::syntax::ast::LitIntType {
     Unsuffixed
 });
 
+impl_stable_hash_for!(enum ::syntax::ast::LitFloatType {
+    Suffixed(float_ty),
+    Unsuffixed
+});
+
 impl_stable_hash_for!(struct ::syntax::ast::Lit {
     kind,
     token,
@@ -148,8 +152,7 @@ impl_stable_hash_for!(enum ::syntax::ast::LitKind {
     Byte(value),
     Char(value),
     Int(value, lit_int_type),
-    Float(value, float_ty),
-    FloatUnsuffixed(value),
+    Float(value, lit_float_type),
     Bool(value),
     Err(value)
 });
@@ -159,6 +162,7 @@ impl_stable_hash_for_spanned!(::syntax::ast::LitKind);
 impl_stable_hash_for!(enum ::syntax::ast::IntTy { Isize, I8, I16, I32, I64, I128 });
 impl_stable_hash_for!(enum ::syntax::ast::UintTy { Usize, U8, U16, U32, U64, U128 });
 impl_stable_hash_for!(enum ::syntax::ast::FloatTy { F32, F64 });
+impl_stable_hash_for!(enum ::rustc_target::abi::FloatTy { F32, F64 });
 impl_stable_hash_for!(enum ::syntax::ast::Unsafety { Unsafe, Normal });
 impl_stable_hash_for!(enum ::syntax::ast::Constness { Const, NotConst });
 impl_stable_hash_for!(enum ::syntax::ast::Defaultness { Default, Final });

src/librustc/infer/error_reporting/mod.rs

@@ -897,11 +897,7 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> {
             } else {
                 r.push(' ');
             }
-            s.push_highlighted(format!(
-                "&{}{}",
-                r,
-                if mutbl == hir::MutMutable { "mut " } else { "" }
-            ));
+            s.push_highlighted(format!("&{}{}", r, mutbl.prefix_str()));
             s.push_normal(ty.to_string());
         }
 

src/librustc/ty/layout.rs

@@ -538,7 +538,10 @@ impl<'tcx> LayoutCx<'tcx, TyCtxt<'tcx>> {
             ty::Uint(ity) => {
                 scalar(Int(Integer::from_attr(dl, attr::UnsignedInt(ity)), false))
             }
-            ty::Float(fty) => scalar(Float(fty)),
+            ty::Float(fty) => scalar(Float(match fty {
+                ast::FloatTy::F32 => FloatTy::F32,
+                ast::FloatTy::F64 => FloatTy::F64,
+            })),
             ty::FnPtr(_) => {
                 let mut ptr = scalar_unit(Pointer);
                 ptr.valid_range = 1..=*ptr.valid_range.end();