Add forever unstable attribute to allow specifying arbitrary scalar ranges

src/librustc/middle/region.rs

@@ -21,6 +21,7 @@ use util::nodemap::{FxHashMap, FxHashSet};
 use ty;
 
 use std::mem;
+use std::fmt;
 use rustc_data_structures::sync::Lrc;
 use syntax::source_map;
 use syntax::ast;
@@ -50,7 +51,7 @@ use rustc_data_structures::stable_hasher::{HashStable, StableHasher,
 /// `DestructionScope`, but those that are `terminating_scopes` do;
 /// see discussion with `ScopeTree`.
 ///
-/// `Remainder(BlockRemainder { block, statement_index })` represents
+/// `Remainder { block, statement_index }` represents
 /// the scope of user code running immediately after the initializer
 /// expression for the indexed statement, until the end of the block.
 ///
@@ -99,12 +100,29 @@ use rustc_data_structures::stable_hasher::{HashStable, StableHasher,
 /// placate the same deriving in `ty::FreeRegion`, but we may want to
 /// actually attach a more meaningful ordering to scopes than the one
 /// generated via deriving here.
-#[derive(Clone, PartialEq, PartialOrd, Eq, Ord, Hash, Debug, Copy, RustcEncodable, RustcDecodable)]
+#[derive(Clone, PartialEq, PartialOrd, Eq, Ord, Hash, Copy, RustcEncodable, RustcDecodable)]
 pub struct Scope {
     pub(crate) id: hir::ItemLocalId,
     pub(crate) data: ScopeData,
 }
 
+impl fmt::Debug for Scope {
+    fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
+        match self.data {
+            ScopeData::Node => write!(fmt, "Node({:?})", self.id),
+            ScopeData::CallSite => write!(fmt, "CallSite({:?})", self.id),
+            ScopeData::Arguments => write!(fmt, "Arguments({:?})", self.id),
+            ScopeData::Destruction => write!(fmt, "Destruction({:?})", self.id),
+            ScopeData::Remainder(fsi) => write!(
+                fmt,
+                "Remainder {{ block: {:?}, first_statement_index: {}}}",
+                self.id,
+                fsi.as_u32(),
+            ),
+        }
+    }
+}
+
 #[derive(Clone, PartialEq, PartialOrd, Eq, Ord, Hash, Debug, Copy, RustcEncodable, RustcDecodable)]
 pub enum ScopeData {
     Node,
@@ -152,14 +170,14 @@ impl_stable_hash_for!(struct ::middle::region::FirstStatementIndex { private });
 #[allow(dead_code)]
 // only works on stage 1 when the rustc_layout_scalar_valid_range attribute actually exists
 #[cfg(not(stage0))]
-static ASSERT: () = [()][(mem::size_of::<ScopeData>() != 4) as usize];
+static ASSERT: () = [()][!(mem::size_of::<ScopeData>() == 4) as usize];
 
 #[allow(non_snake_case)]
 impl Scope {
     #[inline]
     pub fn data(self) -> ScopeData {
         self.data
-        }
+    }
 
     #[inline]
     pub fn new(id: hir::ItemLocalId, data: ScopeData) -> Self {

src/librustc/ty/context.rs

@@ -830,9 +830,9 @@ impl<'tcx> CommonTypes<'tcx> {
     fn new(interners: &CtxtInterners<'tcx>) -> CommonTypes<'tcx> {
         // Ensure our type representation does not grow
         #[cfg(all(not(stage0), target_pointer_width = "64"))]
-        assert!(mem::size_of::<ty::TyKind>() <= 24);
+        static ASSERT_TY_KIND: () = [()][!(std::mem::size_of::<ty::TyKind>() <= 24) as usize];
         #[cfg(all(not(stage0), target_pointer_width = "64"))]
-        assert!(mem::size_of::<ty::TyS>() <= 32);
+        static ASSERT_TYS: () = [()][!(std::mem::size_of::<ty::TyS>() <= 32) as usize];
 
         let mk = |sty| CtxtInterners::intern_ty(interners, interners, sty);
         let mk_region = |r| {

src/test/mir-opt/validate_1.rs

@@ -64,11 +64,11 @@ fn main() {
 //     bb0: {
 //         Validate(Acquire, [_1: &ReFree(DefId(0/1:11 ~ validate_1[317d]::main[0]::{{closure}}[0]), BrEnv) [closure@NodeId(50)], _2: &ReFree(DefId(0/1:11 ~ validate_1[317d]::main[0]::{{closure}}[0]), BrAnon(0)) mut i32]);
 //         StorageLive(_3);
-//         Validate(Suspend(ReScope(Remainder(BlockRemainder { block: ItemLocalId(25), first_statement_index: 0 }))), [(*_2): i32]);
+//         Validate(Suspend(ReScope(Remainder { block: ItemLocalId(25), first_statement_index: 0 })), [(*_2): i32]);
 //         _3 = &ReErased (*_2);
-//         Validate(Acquire, [(*_3): i32/ReScope(Remainder(BlockRemainder { block: ItemLocalId(25), first_statement_index: 0 })) (imm)]);
+//         Validate(Acquire, [(*_3): i32/ReScope(Remainder { block: ItemLocalId(25), first_statement_index: 0 }) (imm)]);
 //         _0 = (*_3);
-//         EndRegion(ReScope(Remainder(BlockRemainder { block: ItemLocalId(25), first_statement_index: 0 })));
+//         EndRegion(ReScope(Remainder { block: ItemLocalId(25), first_statement_index: 0 }));
 //         StorageDead(_3);
 //         return;
 //     }

src/test/mir-opt/validate_3.rs

@@ -48,12 +48,12 @@ fn main() {
 //         StorageLive(_1);
 //         _1 = Test { x: const 0i32 };
 //         StorageLive(_2);
-//         Validate(Suspend(ReScope(Remainder(BlockRemainder { block: ItemLocalId(20), first_statement_index: 3 }))), [_1: Test]);
+//         Validate(Suspend(ReScope(Remainder { block: ItemLocalId(20), first_statement_index: 3 })), [_1: Test]);
 //         _2 = &ReErased _1;
-//         Validate(Acquire, [(*_2): Test/ReScope(Remainder(BlockRemainder { block: ItemLocalId(20), first_statement_index: 3 })) (imm)]);
+//         Validate(Acquire, [(*_2): Test/ReScope(Remainder { block: ItemLocalId(20), first_statement_index: 3 }) (imm)]);
 //         StorageLive(_4);
 //         StorageLive(_5);
-//         Validate(Suspend(ReScope(Node(ItemLocalId(18)))), [((*_2).0: i32): i32/ReScope(Remainder(BlockRemainder { block: ItemLocalId(20), first_statement_index: 3 })) (imm)]);
+//         Validate(Suspend(ReScope(Node(ItemLocalId(18)))), [((*_2).0: i32): i32/ReScope(Remainder { block: ItemLocalId(20), first_statement_index: 3 }) (imm)]);
 //         _5 = &ReErased ((*_2).0: i32);
 //         Validate(Acquire, [(*_5): i32/ReScope(Node(ItemLocalId(18))) (imm)]);
 //         Validate(Suspend(ReScope(Node(ItemLocalId(18)))), [(*_5): i32/ReScope(Node(ItemLocalId(18))) (imm)]);
@@ -68,7 +68,7 @@ fn main() {
 //         StorageDead(_4);
 //         StorageDead(_5);
 //         _0 = ();
-//         EndRegion(ReScope(Remainder(BlockRemainder { block: ItemLocalId(20), first_statement_index: 3 })));
+//         EndRegion(ReScope(Remainder { block: ItemLocalId(20), first_statement_index: 3 }));
 //         StorageDead(_2);
 //         StorageDead(_1);
 //         return;

src/test/ui/consts/const-eval/zst_operand_eval.rs

@@ -1,5 +1,5 @@
 // compile-pass
 
-static ASSERT: () = [()][(std::mem::size_of::<u32>() != 4) as usize];
+static ASSERT: () = [()][!(std::mem::size_of::<u32>() == 4) as usize];
 
 fn main() {}