make rustc_target usable outside of rustc

Author: HKalbasi

compiler/rustc_index/Cargo.toml

@@ -7,6 +7,10 @@ edition = "2021"
 
 [dependencies]
 arrayvec = { version = "0.7", default-features = false }
-rustc_serialize = { path = "../rustc_serialize" }
-rustc_macros = { path = "../rustc_macros" }
+rustc_serialize = { path = "../rustc_serialize", optional = true }
+rustc_macros = { path = "../rustc_macros", optional = true }
 smallvec = "1.8.1"
+
+[features]
+default = ["nightly"]
+nightly = ["rustc_serialize", "rustc_macros"]

compiler/rustc_index/src/lib.rs

@@ -1,17 +1,20 @@
 #![deny(rustc::untranslatable_diagnostic)]
 #![deny(rustc::diagnostic_outside_of_impl)]
-#![feature(allow_internal_unstable)]
-#![feature(extend_one)]
-#![feature(min_specialization)]
-#![feature(new_uninit)]
-#![feature(step_trait)]
-#![feature(stmt_expr_attributes)]
-#![feature(test)]
+#![cfg_attr(feature = "nightly", feature(allow_internal_unstable))]
+#![cfg_attr(feature = "nightly", feature(extend_one))]
+#![cfg_attr(feature = "nightly", feature(min_specialization))]
+#![cfg_attr(feature = "nightly", feature(new_uninit))]
+#![cfg_attr(feature = "nightly", feature(step_trait))]
+#![cfg_attr(feature = "nightly", feature(stmt_expr_attributes))]
+#![cfg_attr(feature = "nightly", feature(test))]
 
+#[cfg(feature = "nightly")]
 pub mod bit_set;
+#[cfg(feature = "nightly")]
 pub mod interval;
 pub mod vec;
 
+#[cfg(feature = "rustc_macros")]
 pub use rustc_macros::newtype_index;
 
 /// Type size assertion. The first argument is a type and the second argument is its expected size.

compiler/rustc_index/src/vec.rs

@@ -1,3 +1,4 @@
+#[cfg(feature = "rustc_serialize")]
 use rustc_serialize::{Decodable, Decoder, Encodable, Encoder};
 
 use std::fmt;
@@ -61,12 +62,14 @@ pub struct IndexVec<I: Idx, T> {
 // not the phantom data.
 unsafe impl<I: Idx, T> Send for IndexVec<I, T> where T: Send {}
 
+#[cfg(feature = "rustc_serialize")]
 impl<S: Encoder, I: Idx, T: Encodable<S>> Encodable<S> for IndexVec<I, T> {
     fn encode(&self, s: &mut S) {
         Encodable::encode(&self.raw, s);
     }
 }
 
+#[cfg(feature = "rustc_serialize")]
 impl<D: Decoder, I: Idx, T: Decodable<D>> Decodable<D> for IndexVec<I, T> {
     fn decode(d: &mut D) -> Self {
         IndexVec { raw: Decodable::decode(d), _marker: PhantomData }
@@ -359,11 +362,13 @@ impl<I: Idx, T> Extend<T> for IndexVec<I, T> {
     }
 
     #[inline]
+    #[cfg(feature = "nightly")]
     fn extend_one(&mut self, item: T) {
         self.raw.push(item);
     }
 
     #[inline]
+    #[cfg(feature = "nightly")]
     fn extend_reserve(&mut self, additional: usize) {
         self.raw.reserve(additional);
     }

compiler/rustc_middle/src/arena.rs

@@ -6,7 +6,7 @@
 macro_rules! arena_types {
     ($macro:path) => (
         $macro!([
-            [] layout: rustc_target::abi::LayoutS<'tcx>,
+            [] layout: rustc_target::abi::LayoutS<rustc_target::abi::VariantIdx>,
             [] fn_abi: rustc_target::abi::call::FnAbi<'tcx, rustc_middle::ty::Ty<'tcx>>,
             // AdtDef are interned and compared by address
             [decode] adt_def: rustc_middle::ty::AdtDefData,

compiler/rustc_middle/src/ty/context.rs

@@ -148,7 +148,7 @@ pub struct CtxtInterners<'tcx> {
     const_: InternedSet<'tcx, ConstS<'tcx>>,
     const_allocation: InternedSet<'tcx, Allocation>,
     bound_variable_kinds: InternedSet<'tcx, List<ty::BoundVariableKind>>,
-    layout: InternedSet<'tcx, LayoutS<'tcx>>,
+    layout: InternedSet<'tcx, LayoutS<VariantIdx>>,
     adt_def: InternedSet<'tcx, AdtDefData>,
 }
 
@@ -2244,7 +2244,7 @@ direct_interners! {
     region: mk_region(RegionKind<'tcx>): Region -> Region<'tcx>,
     const_: mk_const_internal(ConstS<'tcx>): Const -> Const<'tcx>,
     const_allocation: intern_const_alloc(Allocation): ConstAllocation -> ConstAllocation<'tcx>,
-    layout: intern_layout(LayoutS<'tcx>): Layout -> Layout<'tcx>,
+    layout: intern_layout(LayoutS<VariantIdx>): Layout -> Layout<'tcx>,
     adt_def: intern_adt_def(AdtDefData): AdtDef -> AdtDef<'tcx>,
 }
 

compiler/rustc_middle/src/ty/layout.rs

@@ -610,7 +610,7 @@ where
                 })
             }
 
-            Variants::Multiple { ref variants, .. } => variants[variant_index],
+            Variants::Multiple { ref variants, .. } => cx.tcx().intern_layout(variants[variant_index].clone()),
         };
 
         assert_eq!(*layout.variants(), Variants::Single { index: variant_index });

compiler/rustc_target/Cargo.toml

@@ -7,9 +7,20 @@ edition = "2021"
 bitflags = "1.2.1"
 tracing = "0.1"
 serde_json = "1.0.59"
-rustc_data_structures = { path = "../rustc_data_structures" }
-rustc_feature = { path = "../rustc_feature" }
-rustc_index = { path = "../rustc_index" }
-rustc_macros = { path = "../rustc_macros" }
-rustc_serialize = { path = "../rustc_serialize" }
-rustc_span = { path = "../rustc_span" }
+rustc_data_structures = { path = "../rustc_data_structures", optional = true  }
+rustc_feature = { path = "../rustc_feature", optional = true }
+rustc_index = { path = "../rustc_index", default-features = false }
+rustc_macros = { path = "../rustc_macros", optional = true }
+rustc_serialize = { path = "../rustc_serialize", optional = true  }
+rustc_span = { path = "../rustc_span", optional = true }
+
+[features]
+default = ["nightly"]
+nightly = [
+    "rustc_data_structures",
+    "rustc_feature",
+    "rustc_index/nightly",
+    "rustc_macros",
+    "rustc_serialize",
+    "rustc_span",
+]