Move check_for_entry_fn and check_unused to a later stage

Author: Zoxc

src/librustc_interface/passes.rs

@@ -871,6 +871,9 @@ fn analysis(tcx: TyCtxt<'_>, cnum: CrateNum) -> Result<()> {
                         tcx.ensure().check_mod_intrinsics(local_def_id);
                     });
                 });
+            },
+            {
+                typeck::check_crate_late(tcx);
             }
         );
     });

src/librustc_typeck/check_unused.rs

@@ -10,6 +10,8 @@ use rustc_span::Span;
 use syntax::ast;
 
 pub fn check_crate(tcx: TyCtxt<'_>) {
+    let _timer = tcx.sess.timer("check_unused_imports");
+
     let mut used_trait_imports = DefIdSet::default();
     for &body_id in tcx.hir().krate().bodies.keys() {
         let item_def_id = tcx.hir().body_owner_def_id(body_id);

src/librustc_typeck/lib.rs

@@ -290,6 +290,7 @@ fn check_start_fn_ty(tcx: TyCtxt<'_>, start_def_id: DefId) {
 }
 
 fn check_for_entry_fn(tcx: TyCtxt<'_>) {
+    let _timer = tcx.sess.prof.generic_activity("check_entry_fn");
     match tcx.entry_fn(LOCAL_CRATE) {
         Some((def_id, EntryFnType::Main)) => check_main_fn_ty(tcx, def_id),
         Some((def_id, EntryFnType::Start)) => check_start_fn_ty(tcx, def_id),
@@ -361,12 +362,13 @@ pub fn check_crate(tcx: TyCtxt<'_>) -> Result<(), ErrorReported> {
         )
     });
 
-    check_unused::check_crate(tcx);
-    check_for_entry_fn(tcx);
-
     if tcx.sess.err_count() == 0 { Ok(()) } else { Err(ErrorReported) }
 }
 
+pub fn check_crate_late(tcx: TyCtxt<'_>) {
+    join(|| check_unused::check_crate(tcx), || check_for_entry_fn(tcx));
+}
+
 /// A quasi-deprecated helper used in rustdoc and clippy to get
 /// the type from a HIR node.
 pub fn hir_ty_to_ty<'tcx>(tcx: TyCtxt<'tcx>, hir_ty: &hir::Ty<'_>) -> Ty<'tcx> {

src/test/ui/bad/bad-expr-path.rs

@@ -1,6 +1,6 @@
 mod m1 {}
 
-fn main(arguments: Vec<String>) { //~ ERROR `main` function has wrong type
+fn main(arguments: Vec<String>) {
     log(debug, m1::arguments);
     //~^ ERROR cannot find function `log` in this scope
     //~| ERROR cannot find value `debug` in this scope

src/test/ui/bad/bad-expr-path.stderr

@@ -16,16 +16,6 @@ error[E0425]: cannot find value `arguments` in module `m1`
 LL |     log(debug, m1::arguments);
    |                    ^^^^^^^^^ not found in `m1`
 
-error[E0580]: `main` function has wrong type
-  --> $DIR/bad-expr-path.rs:3:1
-   |
-LL | fn main(arguments: Vec<String>) {
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ incorrect number of function parameters
-   |
-   = note: expected fn pointer `fn()`
-              found fn pointer `fn(std::vec::Vec<std::string::String>)`
-
-error: aborting due to 4 previous errors
+error: aborting due to 3 previous errors
 
-Some errors have detailed explanations: E0425, E0580.
-For more information about an error, try `rustc --explain E0425`.
+For more information about this error, try `rustc --explain E0425`.

src/test/ui/bad/bad-expr-path2.rs

@@ -2,7 +2,7 @@ mod m1 {
     pub mod arguments {}
 }
 
-fn main(arguments: Vec<String>) { //~ ERROR `main` function has wrong type
+fn main(arguments: Vec<String>) {
     log(debug, m1::arguments);
     //~^ ERROR cannot find function `log` in this scope
     //~| ERROR cannot find value `debug` in this scope

src/test/ui/bad/bad-expr-path2.stderr

@@ -16,16 +16,7 @@ error[E0423]: expected value, found module `m1::arguments`
 LL |     log(debug, m1::arguments);
    |                ^^^^^^^^^^^^^ not a value
 
-error[E0580]: `main` function has wrong type
-  --> $DIR/bad-expr-path2.rs:5:1
-   |
-LL | fn main(arguments: Vec<String>) {
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ incorrect number of function parameters
-   |
-   = note: expected fn pointer `fn()`
-              found fn pointer `fn(std::vec::Vec<std::string::String>)`
-
-error: aborting due to 4 previous errors
+error: aborting due to 3 previous errors
 
-Some errors have detailed explanations: E0423, E0425, E0580.
+Some errors have detailed explanations: E0423, E0425.
 For more information about an error, try `rustc --explain E0423`.

src/test/ui/lint/lint-unused-imports-2.rs

@@ -0,0 +1,23 @@
+#![deny(unused_imports)]
+#![allow(dead_code)]
+
+// Be sure that if we just bring some methods into scope that they're also
+// counted as being used.
+use test::B;
+// But only when actually used: do not get confused by the method with the same name.
+use test::B2; //~ ERROR unused import: `test::B2`
+
+mod test {
+    pub trait B {
+        fn b(&self) {}
+    }
+    pub trait B2 {
+        fn b(&self) {}
+    }
+    pub struct C;
+    impl B for C {}
+}
+
+fn main() {
+    test::C.b();
+}

src/test/ui/lint/lint-unused-imports-2.stderr

@@ -0,0 +1,14 @@
+error: unused import: `test::B2`
+  --> $DIR/lint-unused-imports-2.rs:8:5
+   |
+LL | use test::B2;
+   |     ^^^^^^^^
+   |
+note: lint level defined here
+  --> $DIR/lint-unused-imports-2.rs:1:9
+   |
+LL | #![deny(unused_imports)]
+   |         ^^^^^^^^^^^^^^
+
+error: aborting due to previous error
+

src/test/ui/lint/lint-unused-imports.rs

@@ -13,11 +13,6 @@ use std::option::Option::{Some, None};
 //~^ ERROR unused imports: `None`, `Some`
 
 use test::A;       //~ ERROR unused import: `test::A`
-// Be sure that if we just bring some methods into scope that they're also
-// counted as being used.
-use test::B;
-// But only when actually used: do not get confused by the method with the same name.
-use test::B2; //~ ERROR unused import: `test::B2`
 
 // Make sure this import is warned about when at least one of its imported names
 // is unused
@@ -30,11 +25,6 @@ mod test2 {
 
 mod test {
     pub trait A { fn a(&self) {} }
-    pub trait B { fn b(&self) {} }
-    pub trait B2 { fn b(&self) {} }
-    pub struct C;
-    impl A for C {}
-    impl B for C {}
 }
 
 mod foo {
@@ -85,6 +75,5 @@ fn main() {
     let mut a = 3;
     let mut b = 4;
     swap(&mut a, &mut b);
-    test::C.b();
     let _a = foo();
 }