Auto merge of #122078 - gurry:121443-ice-layout-is-sized-alt, r=oli-obk

Check that return type is WF in typeck

Ensures that non-WF types do not pass typeck and then later ICE in MIR/const eval

Fixes #121443

2 files changed, 61 insertions, 0 deletions

diff --git a/tests/ui/trait-bounds/ice-unsized-tuple-const-issue-121443.rs b/tests/ui/trait-bounds/ice-unsized-tuple-const-issue-121443.rs
new file mode 100644
index 00000000000..c3a2ab82adc
--- /dev/null
+++ b/tests/ui/trait-bounds/ice-unsized-tuple-const-issue-121443.rs
@@ -0,0 +1,16 @@
+// Regression test for #121443
+// Checks that no ICE occurs upon encountering
+// a tuple with unsized element that is not
+// the last element
+
+type Fn = dyn FnOnce() -> u8;
+
+const TEST: Fn = some_fn;
+//~^ ERROR cannot find value `some_fn` in this scope
+//~| ERROR the size for values of type `(dyn FnOnce() -> u8 + 'static)` cannot be known at compilation time
+//~| ERROR the size for values of type `(dyn FnOnce() -> u8 + 'static)` cannot be known at compilation time
+const TEST2: (Fn, u8) = (TEST, 0);
+//~^ ERROR the size for values of type `(dyn FnOnce() -> u8 + 'static)` cannot be known at compilation time
+//~| ERROR the size for values of type `(dyn FnOnce() -> u8 + 'static)` cannot be known at compilation time
+
+fn main() {}
diff --git a/tests/ui/trait-bounds/ice-unsized-tuple-const-issue-121443.stderr b/tests/ui/trait-bounds/ice-unsized-tuple-const-issue-121443.stderr
new file mode 100644
index 00000000000..0e92979ccd5
--- /dev/null
+++ b/tests/ui/trait-bounds/ice-unsized-tuple-const-issue-121443.stderr
@@ -0,0 +1,45 @@
+error[E0425]: cannot find value `some_fn` in this scope
+  --> $DIR/ice-unsized-tuple-const-issue-121443.rs:8:18
+   |
+LL | const TEST: Fn = some_fn;
+   |                  ^^^^^^^ not found in this scope
+
+error[E0277]: the size for values of type `(dyn FnOnce() -> u8 + 'static)` cannot be known at compilation time
+  --> $DIR/ice-unsized-tuple-const-issue-121443.rs:8:13
+   |
+LL | const TEST: Fn = some_fn;
+   |             ^^ doesn't have a size known at compile-time
+   |
+   = help: the trait `Sized` is not implemented for `(dyn FnOnce() -> u8 + 'static)`
+
+error[E0277]: the size for values of type `(dyn FnOnce() -> u8 + 'static)` cannot be known at compilation time
+  --> $DIR/ice-unsized-tuple-const-issue-121443.rs:8:18
+   |
+LL | const TEST: Fn = some_fn;
+   |                  ^^^^^^^ doesn't have a size known at compile-time
+   |
+   = help: the trait `Sized` is not implemented for `(dyn FnOnce() -> u8 + 'static)`
+   = note: constant expressions must have a statically known size
+
+error[E0277]: the size for values of type `(dyn FnOnce() -> u8 + 'static)` cannot be known at compilation time
+  --> $DIR/ice-unsized-tuple-const-issue-121443.rs:12:14
+   |
+LL | const TEST2: (Fn, u8) = (TEST, 0);
+   |              ^^^^^^^^ doesn't have a size known at compile-time
+   |
+   = help: the trait `Sized` is not implemented for `(dyn FnOnce() -> u8 + 'static)`
+   = note: only the last element of a tuple may have a dynamically sized type
+
+error[E0277]: the size for values of type `(dyn FnOnce() -> u8 + 'static)` cannot be known at compilation time
+  --> $DIR/ice-unsized-tuple-const-issue-121443.rs:12:25
+   |
+LL | const TEST2: (Fn, u8) = (TEST, 0);
+   |                         ^^^^^^^^^ doesn't have a size known at compile-time
+   |
+   = help: the trait `Sized` is not implemented for `(dyn FnOnce() -> u8 + 'static)`
+   = note: only the last element of a tuple may have a dynamically sized type
+
+error: aborting due to 5 previous errors
+
+Some errors have detailed explanations: E0277, E0425.
+For more information about an error, try `rustc --explain E0277`.