Move unused-extern-crate to late pass

Author: ishitatsuyuki

src/Cargo.lock

@@ -10,7 +10,6 @@
 
 #![deny(warnings)]
 
-#![feature(alloc)]
 #![feature(attr_literals)]
 #![feature(box_syntax)]
 #![feature(inclusive_range_syntax)]
@@ -27,14 +26,10 @@
 #![feature(splice)]
 #![feature(str_escape)]
 #![feature(string_retain)]
-#![feature(test)]
 #![feature(unboxed_closures)]
 #![feature(unicode)]
 
-extern crate alloc;
-extern crate test;
 extern crate std_unicode;
-extern crate core;
 
 use std::hash::{Hash, Hasher};
 use std::collections::hash_map::DefaultHasher;

src/liballoc/tests/lib.rs

@@ -26,7 +26,6 @@
 #![feature(inclusive_range)]
 #![feature(inclusive_range_syntax)]
 #![feature(iter_rfind)]
-#![feature(libc)]
 #![feature(nonzero)]
 #![feature(ord_max_min)]
 #![feature(rand)]
@@ -41,13 +40,10 @@
 #![feature(test)]
 #![feature(trusted_len)]
 #![feature(try_from)]
-#![feature(unicode)]
 #![feature(unique)]
 
 extern crate core;
 extern crate test;
-extern crate libc;
-extern crate std_unicode;
 extern crate rand;
 
 mod any;

src/libcore/tests/lib.rs

@@ -522,6 +522,8 @@ define_dep_nodes!( <'tcx>
     [] DylibDepFormats(DefId),
     [] IsAllocator(DefId),
     [] IsPanicRuntime(DefId),
+    [] IsCompilerBuiltins(DefId),
+    [] HasGlobalAllocator(DefId),
     [] ExternCrate(DefId),
     [] LintLevels,
 );

src/librustc/dep_graph/dep_node.rs

@@ -26,7 +26,6 @@
 #![feature(core_intrinsics)]
 #![feature(discriminant_value)]
 #![feature(i128_type)]
-#![feature(libc)]
 #![feature(never_type)]
 #![feature(nonzero)]
 #![feature(quote)]
@@ -45,7 +44,6 @@ extern crate core;
 extern crate fmt_macros;
 extern crate getopts;
 extern crate graphviz;
-extern crate libc;
 extern crate owning_ref;
 extern crate rustc_back;
 extern crate rustc_data_structures;
@@ -62,7 +60,9 @@ extern crate serialize as rustc_serialize; // used by deriving
 
 // Note that librustc doesn't actually depend on these crates, see the note in
 // `Cargo.toml` for this crate about why these are here.
+#[allow(unused_extern_crates)]
 extern crate flate2;
+#[allow(unused_extern_crates)]
 extern crate test;
 
 #[macro_use]

src/librustc/lib.rs

@@ -797,6 +797,8 @@ pub struct GlobalCtxt<'tcx> {
 
     pub maybe_unused_trait_imports: NodeSet,
 
+    pub maybe_unused_extern_crates: Vec<(NodeId, Span, CrateNum)>,
+
     // Internal cache for metadata decoding. No need to track deps on this.
     pub rcache: RefCell<FxHashMap<ty::CReaderCacheKey, Ty<'tcx>>>,
 
@@ -1038,6 +1040,7 @@ impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> {
             mir_passes,
             freevars: RefCell::new(resolutions.freevars),
             maybe_unused_trait_imports: resolutions.maybe_unused_trait_imports,
+            maybe_unused_extern_crates: resolutions.maybe_unused_extern_crates,
             rcache: RefCell::new(FxHashMap()),
             normalized_cache: RefCell::new(FxHashMap()),
             inhabitedness_cache: RefCell::new(FxHashMap()),

src/librustc/ty/context.rs

@@ -516,6 +516,18 @@ impl<'tcx> QueryDescription for queries::is_panic_runtime<'tcx> {
     }
 }
 
+impl<'tcx> QueryDescription for queries::is_compiler_builtins<'tcx> {
+    fn describe(_: TyCtxt, _: DefId) -> String {
+        "checking if the crate is_compiler_builtins".to_string()
+    }
+}
+
+impl<'tcx> QueryDescription for queries::has_global_allocator<'tcx> {
+    fn describe(_: TyCtxt, _: DefId) -> String {
+        "checking if the crate has_global_allocator".to_string()
+    }
+}
+
 impl<'tcx> QueryDescription for queries::extern_crate<'tcx> {
     fn describe(_: TyCtxt, _: DefId) -> String {
         "getting crate's ExternCrateData".to_string()
@@ -1079,6 +1091,8 @@ define_maps! { <'tcx>
 
     [] is_allocator: IsAllocator(DefId) -> bool,
     [] is_panic_runtime: IsPanicRuntime(DefId) -> bool,
+    [] is_compiler_builtins: IsCompilerBuiltins(DefId) -> bool,
+    [] has_global_allocator: HasGlobalAllocator(DefId) -> bool,
 
     [] extern_crate: ExternCrate(DefId) -> Rc<Option<ExternCrate>>,
 

src/librustc/ty/maps.rs

@@ -131,6 +131,7 @@ pub struct Resolutions {
     pub freevars: FreevarMap,
     pub trait_map: TraitMap,
     pub maybe_unused_trait_imports: NodeSet,
+    pub maybe_unused_extern_crates: Vec<(NodeId, Span, CrateNum)>,
     pub export_map: ExportMap,
 }
 

src/librustc/ty/mod.rs

@@ -15,6 +15,5 @@ syntax = { path = "../libsyntax" }
 syntax_pos = { path = "../libsyntax_pos" }
 graphviz = { path = "../libgraphviz" }
 rustc = { path = "../librustc" }
-rustc_data_structures = { path = "../librustc_data_structures" }
 rustc_mir = { path = "../librustc_mir" }
 rustc_errors = { path = "../librustc_errors" }

src/librustc_borrowck/Cargo.toml

@@ -28,9 +28,7 @@ extern crate rustc_errors as errors;
 extern crate graphviz as dot;
 #[macro_use]
 extern crate rustc;
-extern crate rustc_data_structures;
 extern crate rustc_mir;
-extern crate core; // for NonZero
 
 pub use borrowck::check_crate;
 pub use borrowck::build_borrowck_dataflow_data_for_fn;