Run check_match and check_liveness when MIR is built instead of h…

…aving an explicit phase for them

compiler/rustc_interface/src/passes.rs

@@ -761,27 +761,6 @@ fn analysis(tcx: TyCtxt<'_>, (): ()) -> Result<()> {
     // passes are timed inside typeck
     rustc_hir_analysis::check_crate(tcx)?;
 
-    sess.time("misc_checking_2", || {
-        parallel!(
-            {
-                sess.time("match_checking", || {
-                    tcx.hir().par_body_owners(|def_id| tcx.ensure().check_match(def_id))
-                });
-            },
-            {
-                sess.time("liveness_checking", || {
-                    tcx.hir().par_body_owners(|def_id| {
-                        // this must run before MIR dump, because
-                        // "not all control paths return a value" is reported here.
-                        //
-                        // maybe move the check to a MIR pass?
-                        tcx.ensure().check_liveness(def_id);
-                    });
-                });
-            }
-        );
-    });
-
     sess.time("MIR_borrow_checking", || {
         tcx.hir().par_body_owners(|def_id| tcx.ensure().mir_borrowck(def_id));
     });

compiler/rustc_mir_build/src/build/mod.rs

@@ -51,6 +51,13 @@ fn mir_build(tcx: TyCtxt<'_>, def: LocalDefId) -> Body<'_> {
             // of `mir_build`, so now we can steal it
             let thir = thir.steal();
 
+            tcx.ensure().check_match(def);
+            // this must run before MIR dump, because
+            // "not all control paths return a value" is reported here.
+            //
+            // maybe move the check to a MIR pass?
+            tcx.ensure().check_liveness(def);
+
             match thir.body_type {
                 thir::BodyTy::Fn(fn_sig) => construct_fn(tcx, def, &thir, expr, fn_sig),
                 thir::BodyTy::Const(ty) => construct_const(tcx, def, &thir, expr, ty),

compiler/rustc_passes/src/liveness.rs

@@ -98,6 +98,7 @@ use rustc_middle::ty::query::Providers;
 use rustc_middle::ty::{self, RootVariableMinCaptureList, Ty, TyCtxt};
 use rustc_session::lint;
 use rustc_span::symbol::{kw, sym, Symbol};
+use rustc_span::DUMMY_SP;
 use rustc_span::{BytePos, Span};
 
 use std::collections::VecDeque;
@@ -586,8 +587,13 @@ impl<'a, 'tcx> Liveness<'a, 'tcx> {
     }
 
     fn assigned_on_exit(&self, ln: LiveNode, var: Variable) -> bool {
-        let successor = self.successors[ln].unwrap();
-        self.assigned_on_entry(successor, var)
+        match self.successors[ln] {
+            Some(successor) => self.assigned_on_entry(successor, var),
+            None => {
+                self.ir.tcx.sess.delay_span_bug(DUMMY_SP, "no successor");
+                true
+            }
+        }
     }
 
     fn write_vars<F>(&self, wr: &mut dyn Write, mut test: F) -> io::Result<()>

tests/mir-opt/const_promotion_extern_static.FOO-promoted[0].SimplifyCfg-elaborate-drops.after.mir

@@ -7,15 +7,15 @@ promoted[0] in FOO: &[&i32; 1] = {
     let mut _3: *const i32;              // in scope 0 at $DIR/const_promotion_extern_static.rs:+0:42: +0:43
 
     bb0: {
-        _3 = const {alloc2: *const i32}; // scope 0 at $DIR/const_promotion_extern_static.rs:+0:42: +0:43
+        _3 = const {alloc3: *const i32}; // scope 0 at $DIR/const_promotion_extern_static.rs:+0:42: +0:43
                                          // mir::Constant
                                          // + span: $DIR/const_promotion_extern_static.rs:13:42: 13:43
-                                         // + literal: Const { ty: *const i32, val: Value(Scalar(alloc2)) }
+                                         // + literal: Const { ty: *const i32, val: Value(Scalar(alloc3)) }
         _2 = &(*_3);                     // scope 0 at $DIR/const_promotion_extern_static.rs:+0:41: +0:43
         _1 = [move _2];                  // scope 0 at $DIR/const_promotion_extern_static.rs:+0:31: +0:46
         _0 = &_1;                        // scope 0 at $DIR/const_promotion_extern_static.rs:+0:31: +0:55
         return;                          // scope 0 at $DIR/const_promotion_extern_static.rs:+0:31: +0:55
     }
 }
 
-alloc2 (extern static: X)
+alloc3 (extern static: X)

tests/mir-opt/const_promotion_extern_static.FOO.PromoteTemps.diff

@@ -18,11 +18,11 @@
 -         StorageLive(_3);                 // scope 0 at $DIR/const_promotion_extern_static.rs:+0:31: +0:46
 -         StorageLive(_4);                 // scope 0 at $DIR/const_promotion_extern_static.rs:+0:32: +0:45
 -         StorageLive(_5);                 // scope 1 at $DIR/const_promotion_extern_static.rs:+0:42: +0:43
--         _5 = const {alloc2: *const i32}; // scope 1 at $DIR/const_promotion_extern_static.rs:+0:42: +0:43
+-         _5 = const {alloc3: *const i32}; // scope 1 at $DIR/const_promotion_extern_static.rs:+0:42: +0:43
 +         _6 = const _;                    // scope 0 at $DIR/const_promotion_extern_static.rs:+0:31: +0:55
                                            // mir::Constant
 -                                          // + span: $DIR/const_promotion_extern_static.rs:13:42: 13:43
--                                          // + literal: Const { ty: *const i32, val: Value(Scalar(alloc2)) }
+-                                          // + literal: Const { ty: *const i32, val: Value(Scalar(alloc3)) }
 -         _4 = &(*_5);                     // scope 1 at $DIR/const_promotion_extern_static.rs:+0:41: +0:43
 -         _3 = [move _4];                  // scope 0 at $DIR/const_promotion_extern_static.rs:+0:31: +0:46
 -         _2 = &_3;                        // scope 0 at $DIR/const_promotion_extern_static.rs:+0:31: +0:55
@@ -50,5 +50,5 @@
       }
   }
 - 
-- alloc2 (extern static: X)
+- alloc3 (extern static: X)
 

tests/ui/borrowck/bindings-after-at-or-patterns-slice-patterns-box-patterns.stderr

@@ -1,19 +1,3 @@
-error: cannot borrow value as mutable because it is also borrowed as immutable
-  --> $DIR/bindings-after-at-or-patterns-slice-patterns-box-patterns.rs:36:9
-   |
-LL |         ref foo @ [.., ref mut bar] => (),
-   |         ^^^^^^^        ----------- value is mutably borrowed by `bar` here
-   |         |
-   |         value is borrowed by `foo` here
-
-error: cannot borrow value as mutable because it is also borrowed as immutable
-  --> $DIR/bindings-after-at-or-patterns-slice-patterns-box-patterns.rs:120:9
-   |
-LL |         ref foo @ Some(box ref mut s) => (),
-   |         ^^^^^^^            --------- value is mutably borrowed by `s` here
-   |         |
-   |         value is borrowed by `foo` here
-
 error[E0382]: borrow of moved value: `x`
   --> $DIR/bindings-after-at-or-patterns-slice-patterns-box-patterns.rs:18:5
    |
@@ -43,6 +27,14 @@ LL |     &x;
 LL |     drop(r);
    |          - mutable borrow later used here
 
+error: cannot borrow value as mutable because it is also borrowed as immutable
+  --> $DIR/bindings-after-at-or-patterns-slice-patterns-box-patterns.rs:36:9
+   |
+LL |         ref foo @ [.., ref mut bar] => (),
+   |         ^^^^^^^        ----------- value is mutably borrowed by `bar` here
+   |         |
+   |         value is borrowed by `foo` here
+
 error[E0502]: cannot borrow `x` as mutable because it is also borrowed as immutable
   --> $DIR/bindings-after-at-or-patterns-slice-patterns-box-patterns.rs:50:5
    |
@@ -120,6 +112,14 @@ LL |     &mut x;
 LL |     drop(r);
    |          - immutable borrow later used here
 
+error: cannot borrow value as mutable because it is also borrowed as immutable
+  --> $DIR/bindings-after-at-or-patterns-slice-patterns-box-patterns.rs:120:9
+   |
+LL |         ref foo @ Some(box ref mut s) => (),
+   |         ^^^^^^^            --------- value is mutably borrowed by `s` here
+   |         |
+   |         value is borrowed by `foo` here
+
 error[E0382]: borrow of moved value: `x`
   --> $DIR/bindings-after-at-or-patterns-slice-patterns-box-patterns.rs:134:5
    |

tests/ui/closures/2229_closure_analysis/match/pattern-matching-should-fail.stderr

@@ -1,17 +1,3 @@
-error[E0004]: non-exhaustive patterns: type `u8` is non-empty
-  --> $DIR/pattern-matching-should-fail.rs:67:23
-   |
-LL |     let c1 = || match x { };
-   |                       ^
-   |
-   = note: the matched value is of type `u8`
-help: ensure that all possible cases are being handled by adding a match arm with a wildcard pattern as shown
-   |
-LL ~     let c1 = || match x {
-LL +         _ => todo!(),
-LL ~     };
-   |
-
 error[E0381]: used binding `x` isn't initialized
   --> $DIR/pattern-matching-should-fail.rs:8:23
    |
@@ -69,6 +55,20 @@ LL |     let t: !;
 LL |             match t { };
    |                   ^ `t` used here but it isn't initialized
 
+error[E0004]: non-exhaustive patterns: type `u8` is non-empty
+  --> $DIR/pattern-matching-should-fail.rs:67:23
+   |
+LL |     let c1 = || match x { };
+   |                       ^
+   |
+   = note: the matched value is of type `u8`
+help: ensure that all possible cases are being handled by adding a match arm with a wildcard pattern as shown
+   |
+LL ~     let c1 = || match x {
+LL +         _ => todo!(),
+LL ~     };
+   |
+
 error[E0381]: used binding `x` isn't initialized
   --> $DIR/pattern-matching-should-fail.rs:67:23
    |

tests/ui/lint/lint-uppercase-variables.stderr

@@ -12,12 +12,6 @@ error[E0170]: pattern binding `Foo` is named the same as one of the variants of
 LL |     let Foo = foo::Foo::Foo;
    |         ^^^ help: to match on the variant, qualify the path: `foo::Foo::Foo`
 
-error[E0170]: pattern binding `Foo` is named the same as one of the variants of the type `foo::Foo`
-  --> $DIR/lint-uppercase-variables.rs:33:17
-   |
-LL |     fn in_param(Foo: foo::Foo) {}
-   |                 ^^^ help: to match on the variant, qualify the path: `foo::Foo::Foo`
-
 warning: unused variable: `Foo`
   --> $DIR/lint-uppercase-variables.rs:22:9
    |
@@ -37,6 +31,12 @@ warning: unused variable: `Foo`
 LL |     let Foo = foo::Foo::Foo;
    |         ^^^ help: if this is intentional, prefix it with an underscore: `_Foo`
 
+error[E0170]: pattern binding `Foo` is named the same as one of the variants of the type `foo::Foo`
+  --> $DIR/lint-uppercase-variables.rs:33:17
+   |
+LL |     fn in_param(Foo: foo::Foo) {}
+   |                 ^^^ help: to match on the variant, qualify the path: `foo::Foo::Foo`
+
 warning: unused variable: `Foo`
   --> $DIR/lint-uppercase-variables.rs:33:17
    |

tests/ui/lint/rfc-2383-lint-reason/expect_nested_lint_levels.stderr

@@ -1,15 +1,3 @@
-error: unused variable: `this_is_my_function`
-  --> $DIR/expect_nested_lint_levels.rs:48:9
-   |
-LL |     let this_is_my_function = 3;
-   |         ^^^^^^^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_this_is_my_function`
-   |
-note: the lint level is defined here
-  --> $DIR/expect_nested_lint_levels.rs:45:10
-   |
-LL | #[forbid(unused_variables)]
-   |          ^^^^^^^^^^^^^^^^
-
 warning: variable does not need to be mutable
   --> $DIR/expect_nested_lint_levels.rs:36:13
    |
@@ -25,6 +13,18 @@ note: the lint level is defined here
 LL |         unused_mut,
    |         ^^^^^^^^^^
 
+error: unused variable: `this_is_my_function`
+  --> $DIR/expect_nested_lint_levels.rs:48:9
+   |
+LL |     let this_is_my_function = 3;
+   |         ^^^^^^^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_this_is_my_function`
+   |
+note: the lint level is defined here
+  --> $DIR/expect_nested_lint_levels.rs:45:10
+   |
+LL | #[forbid(unused_variables)]
+   |          ^^^^^^^^^^^^^^^^
+
 warning: this lint expectation is unfulfilled
   --> $DIR/expect_nested_lint_levels.rs:7:5
    |

tests/ui/lint/rfc-2383-lint-reason/force_warn_expected_lints_fulfilled.stderr

@@ -12,12 +12,6 @@ warning: unused variable: `fox_name`
 LL |     let fox_name = "Sir Nibbles";
    |         ^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_fox_name`
 
-warning: unused variable: `this_should_fulfill_the_expectation`
-  --> $DIR/force_warn_expected_lints_fulfilled.rs:43:9
-   |
-LL |     let this_should_fulfill_the_expectation = "The `#[allow]` has no power here";
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_this_should_fulfill_the_expectation`
-
 warning: variable does not need to be mutable
   --> $DIR/force_warn_expected_lints_fulfilled.rs:32:9
    |
@@ -28,6 +22,12 @@ LL |     let mut what_does_the_fox_say = "*ding* *deng* *dung*";
    |
    = note: requested on the command line with `--force-warn unused-mut`
 
+warning: unused variable: `this_should_fulfill_the_expectation`
+  --> $DIR/force_warn_expected_lints_fulfilled.rs:43:9
+   |
+LL |     let this_should_fulfill_the_expectation = "The `#[allow]` has no power here";
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_this_should_fulfill_the_expectation`
+
 warning: denote infinite loops with `loop { ... }`
   --> $DIR/force_warn_expected_lints_fulfilled.rs:10:5
    |

tests/ui/lint/unused/lint-unused-variables.stderr

@@ -10,18 +10,18 @@ note: the lint level is defined here
 LL | #![deny(unused_variables)]
    |         ^^^^^^^^^^^^^^^^
 
-error: unused variable: `b`
-  --> $DIR/lint-unused-variables.rs:14:5
-   |
-LL |     b: i32,
-   |     ^ help: if this is intentional, prefix it with an underscore: `_b`
-
 error: unused variable: `a`
   --> $DIR/lint-unused-variables.rs:22:9
    |
 LL |         a: i32,
    |         ^ help: if this is intentional, prefix it with an underscore: `_a`
 
+error: unused variable: `b`
+  --> $DIR/lint-unused-variables.rs:14:5
+   |
+LL |     b: i32,
+   |     ^ help: if this is intentional, prefix it with an underscore: `_b`
+
 error: unused variable: `b`
   --> $DIR/lint-unused-variables.rs:29:9
    |

tests/ui/liveness/liveness-consts.stderr

@@ -1,32 +1,16 @@
-warning: variable `a` is assigned to, but never used
-  --> $DIR/liveness-consts.rs:7:13
+warning: unused variable: `e`
+  --> $DIR/liveness-consts.rs:24:13
    |
-LL |     let mut a = 0;
-   |             ^
+LL |         let e = 1;
+   |             ^ help: if this is intentional, prefix it with an underscore: `_e`
    |
-   = note: consider using `_a` instead
 note: the lint level is defined here
   --> $DIR/liveness-consts.rs:2:9
    |
 LL | #![warn(unused)]
    |         ^^^^^^
    = note: `#[warn(unused_variables)]` implied by `#[warn(unused)]`
 
-warning: value assigned to `b` is never read
-  --> $DIR/liveness-consts.rs:17:5
-   |
-LL |     b += 1;
-   |     ^
-   |
-   = help: maybe it is overwritten before being read?
-   = note: `#[warn(unused_assignments)]` implied by `#[warn(unused)]`
-
-warning: unused variable: `e`
-  --> $DIR/liveness-consts.rs:24:13
-   |
-LL |         let e = 1;
-   |             ^ help: if this is intentional, prefix it with an underscore: `_e`
-
 warning: unused variable: `s`
   --> $DIR/liveness-consts.rs:33:24
    |
@@ -39,6 +23,29 @@ warning: unused variable: `z`
 LL | pub fn f(x: [u8; { let s = 17; 100 }]) -> [u8;  { let z = 18; 100 }] {
    |                                                       ^ help: if this is intentional, prefix it with an underscore: `_z`
 
+warning: unused variable: `z`
+  --> $DIR/liveness-consts.rs:60:13
+   |
+LL |         let z = 42;
+   |             ^ help: if this is intentional, prefix it with an underscore: `_z`
+
+warning: variable `a` is assigned to, but never used
+  --> $DIR/liveness-consts.rs:7:13
+   |
+LL |     let mut a = 0;
+   |             ^
+   |
+   = note: consider using `_a` instead
+
+warning: value assigned to `b` is never read
+  --> $DIR/liveness-consts.rs:17:5
+   |
+LL |     b += 1;
+   |     ^
+   |
+   = help: maybe it is overwritten before being read?
+   = note: `#[warn(unused_assignments)]` implied by `#[warn(unused)]`
+
 warning: value assigned to `t` is never read
   --> $DIR/liveness-consts.rs:42:9
    |
@@ -53,11 +60,5 @@ warning: unused variable: `w`
 LL |         let w = 10;
    |             ^ help: if this is intentional, prefix it with an underscore: `_w`
 
-warning: unused variable: `z`
-  --> $DIR/liveness-consts.rs:60:13
-   |
-LL |         let z = 42;
-   |             ^ help: if this is intentional, prefix it with an underscore: `_z`
-
 warning: 8 warnings emitted