Auto merge of rust-lang#149389 - ShoyuVanilla:local-region-param-wf, r=lcnr

bors · bors · commit 29fa07e3dbca · 2026-02-14T02:52:05.000Z
WF check lifetime bounds for locals with type params FCP proposal in rust-lang#149389 (comment) Fixes rust-lang#115175 Fixes rust-lang#148854
diff --git a/compiler/rustc_hir_typeck/src/fn_ctxt/_impl.rs b/compiler/rustc_hir_typeck/src/fn_ctxt/_impl.rs
@@ -581,7 +581,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
     where
         T: TypeVisitable<TyCtxt<'tcx>>,
     {
-        t.has_free_regions() || t.has_aliases() || t.has_infer_types()
+        // FIXME(mgca): should this also count stuff with infer consts
+        t.has_free_regions() || t.has_aliases() || t.has_infer_types() || t.has_param()
     }
 
     pub(crate) fn node_ty(&self, id: HirId) -> Ty<'tcx> {
diff --git a/src/ci/docker/scripts/rfl-build.sh b/src/ci/docker/scripts/rfl-build.sh
@@ -3,7 +3,8 @@
 set -euo pipefail
 
 # https://github.com/rust-lang/rust/pull/151534
-LINUX_VERSION=eb268c7972f65fa0b11b051c5ef2b92747bb2b62
+# https://github.com/rust-lang/rust/pull/149389
+LINUX_VERSION=167ea5357eb7c3a39200627a36dfbfe249576192
 
 # Build rustc, rustdoc, cargo, clippy-driver and rustfmt
 ../x.py build --stage 2 library rustdoc clippy rustfmt
diff --git a/tests/mir-opt/inline_coroutine_body.run2-{closure#0}.Inline.panic-abort.diff b/tests/mir-opt/inline_coroutine_body.run2-{closure#0}.Inline.panic-abort.diff
@@ -197,8 +197,8 @@
 +         StorageLive(_40);
 +         _40 = &raw mut _19;
 +         _39 = copy _40 as *mut std::pin::helper::PinHelper<&mut std::future::Ready<()>> (PtrToPtr);
-+         StorageDead(_40);
 +         _37 = copy ((*_39).0: &mut std::future::Ready<()>);
++         StorageDead(_40);
 +         StorageLive(_42);
 +         _42 = Option::<()>::None;
 +         _35 = copy ((*_37).0: std::option::Option<()>);
diff --git a/tests/mir-opt/inline_coroutine_body.run2-{closure#0}.Inline.panic-unwind.diff b/tests/mir-opt/inline_coroutine_body.run2-{closure#0}.Inline.panic-unwind.diff
@@ -208,8 +208,8 @@
 +         StorageLive(_40);
 +         _40 = &raw mut _19;
 +         _39 = copy _40 as *mut std::pin::helper::PinHelper<&mut std::future::Ready<()>> (PtrToPtr);
-+         StorageDead(_40);
 +         _37 = copy ((*_39).0: &mut std::future::Ready<()>);
++         StorageDead(_40);
 +         StorageLive(_42);
 +         _42 = Option::<()>::None;
 +         _35 = copy ((*_37).0: std::option::Option<()>);
diff --git a/tests/mir-opt/instsimplify/casts.redundant.InstSimplify-after-simplifycfg.diff b/tests/mir-opt/instsimplify/casts.redundant.InstSimplify-after-simplifycfg.diff
@@ -9,6 +9,7 @@
       let mut _4: *const &u8;
       scope 1 (inlined generic_cast::<&u8, &u8>) {
           let mut _5: *const &u8;
+          let mut _6: *const &u8;
       }
   
       bb0: {
@@ -17,9 +18,12 @@
           StorageLive(_4);
           _4 = copy _1;
           StorageLive(_5);
-          _5 = copy _4;
--         _3 = move _5 as *const &u8 (PtrToPtr);
-+         _3 = move _5;
+          StorageLive(_6);
+          _6 = copy _4;
+-         _5 = move _6 as *const &u8 (PtrToPtr);
++         _5 = move _6;
+          _3 = copy _5;
+          StorageDead(_6);
           StorageDead(_5);
           StorageDead(_4);
 -         _2 = move _3 as *const &u8 (PtrToPtr);
diff --git a/tests/mir-opt/pre-codegen/slice_index.slice_get_unchecked_mut_range.PreCodegen.after.panic-abort.mir b/tests/mir-opt/pre-codegen/slice_index.slice_get_unchecked_mut_range.PreCodegen.after.panic-abort.mir
@@ -15,7 +15,7 @@ fn slice_get_unchecked_mut_range(_1: &mut [u32], _2: std::ops::Range<usize>) ->
             let _8: usize;
             scope 3 {
                 scope 6 (inlined core::slice::index::get_offset_len_mut_noubcheck::<u32>) {
-                    let _9: *mut u32;
+                    let mut _9: *mut u32;
                     scope 7 {
                         let _10: *mut u32;
                         scope 8 {
diff --git a/tests/mir-opt/pre-codegen/slice_index.slice_get_unchecked_mut_range.PreCodegen.after.panic-unwind.mir b/tests/mir-opt/pre-codegen/slice_index.slice_get_unchecked_mut_range.PreCodegen.after.panic-unwind.mir
@@ -15,7 +15,7 @@ fn slice_get_unchecked_mut_range(_1: &mut [u32], _2: std::ops::Range<usize>) ->
             let _8: usize;
             scope 3 {
                 scope 6 (inlined core::slice::index::get_offset_len_mut_noubcheck::<u32>) {
-                    let _9: *mut u32;
+                    let mut _9: *mut u32;
                     scope 7 {
                         let _10: *mut u32;
                         scope 8 {
diff --git a/tests/mir-opt/pre-codegen/slice_index.slice_index_range.PreCodegen.after.panic-abort.mir b/tests/mir-opt/pre-codegen/slice_index.slice_index_range.PreCodegen.after.panic-abort.mir
@@ -19,7 +19,7 @@ fn slice_index_range(_1: &[u32], _2: std::ops::Range<usize>) -> &[u32] {
                 let mut _6: usize;
             }
             scope 4 (inlined core::slice::index::get_offset_len_noubcheck::<u32>) {
-                let _10: *const u32;
+                let mut _10: *const u32;
                 scope 5 {
                     let _11: *const u32;
                     scope 6 {
diff --git a/tests/mir-opt/pre-codegen/slice_index.slice_index_range.PreCodegen.after.panic-unwind.mir b/tests/mir-opt/pre-codegen/slice_index.slice_index_range.PreCodegen.after.panic-unwind.mir
@@ -19,7 +19,7 @@ fn slice_index_range(_1: &[u32], _2: std::ops::Range<usize>) -> &[u32] {
                 let mut _6: usize;
             }
             scope 4 (inlined core::slice::index::get_offset_len_noubcheck::<u32>) {
-                let _10: *const u32;
+                let mut _10: *const u32;
                 scope 5 {
                     let _11: *const u32;
                     scope 6 {
diff --git a/tests/mir-opt/pre-codegen/slice_index.slice_ptr_get_unchecked_range.PreCodegen.after.panic-abort.mir b/tests/mir-opt/pre-codegen/slice_index.slice_ptr_get_unchecked_range.PreCodegen.after.panic-abort.mir
@@ -13,7 +13,7 @@ fn slice_ptr_get_unchecked_range(_1: *const [u32], _2: std::ops::Range<usize>) -
             let _7: usize;
             scope 3 {
                 scope 6 (inlined core::slice::index::get_offset_len_noubcheck::<u32>) {
-                    let _8: *const u32;
+                    let mut _8: *const u32;
                     scope 7 {
                         let _9: *const u32;
                         scope 8 {
diff --git a/tests/mir-opt/pre-codegen/slice_index.slice_ptr_get_unchecked_range.PreCodegen.after.panic-unwind.mir b/tests/mir-opt/pre-codegen/slice_index.slice_ptr_get_unchecked_range.PreCodegen.after.panic-unwind.mir
@@ -13,7 +13,7 @@ fn slice_ptr_get_unchecked_range(_1: *const [u32], _2: std::ops::Range<usize>) -
             let _7: usize;
             scope 3 {
                 scope 6 (inlined core::slice::index::get_offset_len_noubcheck::<u32>) {
-                    let _8: *const u32;
+                    let mut _8: *const u32;
                     scope 7 {
                         let _9: *const u32;
                         scope 8 {
diff --git a/tests/ui/consts/issue-102117.stderr b/tests/ui/consts/issue-102117.stderr
@@ -2,7 +2,7 @@ error[E0310]: the parameter type `T` may not live long enough
   --> $DIR/issue-102117.rs:17:26
    |
 LL |                 type_id: TypeId::of::<T>(),
-   |                          ^^^^^^^^^^^^^^^^^
+   |                          ^^^^^^^^^^^^^^^
    |                          |
    |                          the parameter type `T` must be valid for the static lifetime...
    |                          ...so that the type `T` will meet its required lifetime bounds
@@ -16,7 +16,7 @@ error[E0310]: the parameter type `T` may not live long enough
   --> $DIR/issue-102117.rs:17:26
    |
 LL |                 type_id: TypeId::of::<T>(),
-   |                          ^^^^^^^^^^^^^^^^^
+   |                          ^^^^^^^^^^^^^^^
    |                          |
    |                          the parameter type `T` must be valid for the static lifetime...
    |                          ...so that the type `T` will meet its required lifetime bounds
diff --git a/tests/ui/higher-ranked/leak-check/candidate-from-env-universe-err-project.current.stderr b/tests/ui/higher-ranked/leak-check/candidate-from-env-universe-err-project.current.stderr
@@ -2,15 +2,10 @@ error[E0308]: mismatched types
   --> $DIR/candidate-from-env-universe-err-project.rs:38:5
    |
 LL |     projection_bound::<T>();
-   |     ^^^^^^^^^^^^^^^^^^^^^^^ one type is more general than the other
+   |     ^^^^^^^^^^^^^^^^^^^^^ one type is more general than the other
    |
    = note: expected associated type `<T as Trait<'static>>::Assoc`
               found associated type `<T as Trait<'a>>::Assoc`
-note: the lifetime requirement is introduced here
-  --> $DIR/candidate-from-env-universe-err-project.rs:19:42
-   |
-LL | fn projection_bound<T: for<'a> Trait<'a, Assoc = usize>>() {}
-   |                                          ^^^^^^^^^^^^^
 
 error[E0308]: mismatched types
   --> $DIR/candidate-from-env-universe-err-project.rs:52:30
diff --git a/tests/ui/nll/issue-98693.stderr b/tests/ui/nll/issue-98693.stderr
@@ -2,7 +2,7 @@ error[E0310]: the parameter type `T` may not live long enough
   --> $DIR/issue-98693.rs:16:9
    |
 LL |         assert_static::<T>();
-   |         ^^^^^^^^^^^^^^^^^^^^
+   |         ^^^^^^^^^^^^^^^^^^
    |         |
    |         the parameter type `T` must be valid for the static lifetime...
    |         ...so that the type `T` will meet its required lifetime bounds
diff --git a/tests/ui/nll/type-test-universe.stderr b/tests/ui/nll/type-test-universe.stderr
@@ -2,7 +2,7 @@ error: `S` does not live long enough
   --> $DIR/type-test-universe.rs:11:5
    |
 LL |     outlives_forall::<S>();
-   |     ^^^^^^^^^^^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^^^^^^^^
 
 error: lifetime may not live long enough
   --> $DIR/type-test-universe.rs:17:5
diff --git a/tests/ui/regions/forall-wf-ref-reflexive.stderr b/tests/ui/regions/forall-wf-ref-reflexive.stderr
@@ -2,7 +2,7 @@ error: `T` does not live long enough
   --> $DIR/forall-wf-ref-reflexive.rs:12:5
    |
 LL |     self_wf2::<T>();
-   |     ^^^^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^
 
 error: aborting due to 1 previous error
 
diff --git a/tests/ui/regions/wf-bound-region-in-local-issue-115175.rs b/tests/ui/regions/wf-bound-region-in-local-issue-115175.rs
@@ -0,0 +1,11 @@
+// A regression test for https://github.com/rust-lang/rust/issues/115175.
+// This used to compile without error despite of unsatisfied outlives bound `T: 'static` on local.
+
+struct Static<T: 'static>(T);
+
+fn test<T>() {
+    let _ = None::<Static<T>>;
+    //~^ ERROR the parameter type `T` may not live long enough
+}
+
+fn main() {}
diff --git a/tests/ui/regions/wf-bound-region-in-local-issue-115175.stderr b/tests/ui/regions/wf-bound-region-in-local-issue-115175.stderr
@@ -0,0 +1,17 @@
+error[E0310]: the parameter type `T` may not live long enough
+  --> $DIR/wf-bound-region-in-local-issue-115175.rs:7:13
+   |
+LL |     let _ = None::<Static<T>>;
+   |             ^^^^^^^^^^^^^^^^^
+   |             |
+   |             the parameter type `T` must be valid for the static lifetime...
+   |             ...so that the type `T` will meet its required lifetime bounds
+   |
+help: consider adding an explicit lifetime bound
+   |
+LL | fn test<T: 'static>() {
+   |          +++++++++
+
+error: aborting due to 1 previous error
+
+For more information about this error, try `rustc --explain E0310`.
diff --git a/tests/ui/regions/wf-bound-region-in-local-soundness-issue-148854.rs b/tests/ui/regions/wf-bound-region-in-local-soundness-issue-148854.rs
@@ -0,0 +1,51 @@
+// A regression test for https://github.com/rust-lang/rust/issues/148854.
+
+use std::cell::OnceCell;
+use std::fmt::Display;
+use std::marker::PhantomData;
+use std::rc::Rc;
+
+type Storage = Rc<OnceCell<Box<dyn Display + 'static>>>;
+
+trait IntoDyn<T> {
+    fn into_dyn(input: T, output: Storage);
+}
+
+struct Inner<T: Display + 'static>(PhantomData<T>);
+impl<T: Display> IntoDyn<T> for Inner<T> {
+    fn into_dyn(input: T, output: Storage) {
+        output.set(Box::new(input)).ok().unwrap();
+    }
+}
+
+struct Outer<T, U: IntoDyn<T>> {
+    input: Option<T>,
+    output: Storage,
+    _phantom: PhantomData<U>,
+}
+impl<T, U: IntoDyn<T>> Drop for Outer<T, U> {
+    fn drop(&mut self) {
+        U::into_dyn(self.input.take().unwrap(), self.output.clone());
+    }
+}
+
+fn extend<T: Display>(x: T) -> Box<dyn Display + 'static> {
+    let storage = Rc::new(OnceCell::new());
+    {
+        // This has to error due to an unsatisfied outlives bound on
+        // `Inner<T: 'static>` as its implicit drop relies on that
+        // bound.
+        let _ =
+            Outer::<T, Inner<T>> { input: Some(x), output: storage.clone(), _phantom: PhantomData };
+        //~^ ERROR: the parameter type `T` may not live long enough
+    }
+    Rc::into_inner(storage).unwrap().into_inner().unwrap()
+}
+
+fn main() {
+    let wrong = {
+        let data = String::from("abc");
+        extend::<&String>(&data)
+    };
+    println!("{wrong}");
+}
diff --git a/tests/ui/regions/wf-bound-region-in-local-soundness-issue-148854.stderr b/tests/ui/regions/wf-bound-region-in-local-soundness-issue-148854.stderr
@@ -0,0 +1,17 @@
+error[E0310]: the parameter type `T` may not live long enough
+  --> $DIR/wf-bound-region-in-local-soundness-issue-148854.rs:39:13
+   |
+LL |             Outer::<T, Inner<T>> { input: Some(x), output: storage.clone(), _phantom: PhantomData };
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |             |
+   |             the parameter type `T` must be valid for the static lifetime...
+   |             ...so that the type `T` will meet its required lifetime bounds
+   |
+help: consider adding an explicit lifetime bound
+   |
+LL | fn extend<T: Display + 'static>(x: T) -> Box<dyn Display + 'static> {
+   |                      +++++++++
+
+error: aborting due to 1 previous error
+
+For more information about this error, try `rustc --explain E0310`.
diff --git a/tests/ui/type-alias-impl-trait/implied_lifetime_wf_check3.stderr b/tests/ui/type-alias-impl-trait/implied_lifetime_wf_check3.stderr
@@ -28,7 +28,7 @@ error[E0310]: the parameter type `A` may not live long enough
   --> $DIR/implied_lifetime_wf_check3.rs:55:5
    |
 LL |     test_type_param::assert_static::<A>()
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |     |
    |     the parameter type `A` must be valid for the static lifetime...
    |     ...so that the type `A` will meet its required lifetime bounds
diff --git a/tests/ui/type-alias-impl-trait/implied_lifetime_wf_check4_static.stderr b/tests/ui/type-alias-impl-trait/implied_lifetime_wf_check4_static.stderr
@@ -21,7 +21,7 @@ error[E0310]: the parameter type `A` may not live long enough
   --> $DIR/implied_lifetime_wf_check4_static.rs:15:5
    |
 LL |     assert_static::<A>()
-   |     ^^^^^^^^^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^^^^^^
    |     |
    |     the parameter type `A` must be valid for the static lifetime...
    |     ...so that the type `A` will meet its required lifetime bounds

Original file line number	Diff line number	Diff line change
`@@ -581,7 +581,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {`
`581`	`581`	`where`
`582`	`582`	`T: TypeVisitable<TyCtxt<'tcx>>,`
`583`	`583`	`{`
`584`		`- t.has_free_regions() \|\| t.has_aliases() \|\| t.has_infer_types()`
	`584`	`+ // FIXME(mgca): should this also count stuff with infer consts`
	`585`	`+ t.has_free_regions() \|\| t.has_aliases() \|\| t.has_infer_types() \|\| t.has_param()`
`585`	`586`	`}`
`586`	`587`
`587`	`588`	`pub(crate) fn node_ty(&self, id: HirId) -> Ty<'tcx> {`
Original file line number	Diff line number	Diff line change
`@@ -19,7 +19,7 @@ fn slice_index_range(_1: &[u32], _2: std::ops::Range<usize>) -> &[u32] {`
`19`	`19`	`let mut _6: usize;`
`20`	`20`	`}`
`21`	`21`	`scope 4 (inlined core::slice::index::get_offset_len_noubcheck::<u32>) {`
`22`		`- let _10: *const u32;`
	`22`	`+ let mut _10: *const u32;`
`23`	`23`	`scope 5 {`
`24`	`24`	`let _11: *const u32;`
`25`	`25`	`scope 6 {`