Auto merge of #97825 - Dylan-DPC:rollup-ya51k1k, r=Dylan-DPC

Rollup of 5 pull requests

Successful merges:

 - #97058 (Various refactors to the incr comp workproduct handling)
 - #97301 (Allow unstable items to be re-exported unstably without requiring the feature be enabled)
 - #97738 (Fix ICEs from zsts within unsized types with non-zero offsets)
 - #97771 (Remove SIGIO reference on Haiku)
 - #97808 (Add some unstable target features for the wasm target codegen)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup

src/test/ui/stability-attribute/allow-unstable-reexport.rs

@@ -0,0 +1,30 @@
+// Allow an unstable re-export without requiring a feature gate.
+// #94972
+
+// aux-build:lint-stability.rs
+// aux-build:lint-stability-reexport.rs
+#![feature(staged_api)]
+#![stable(feature = "lint_stability", since = "1.0.0")]
+
+extern crate lint_stability;
+extern crate lint_stability_reexport;
+
+#[unstable(feature = "unstable_test_feature", issue = "none")]
+pub use lint_stability::unstable;
+
+// We want to confirm that using a re-export through another crate behaves
+// the same way as using an item directly
+#[unstable(feature = "unstable_test_feature", issue = "none")]
+pub use lint_stability_reexport::unstable_text;
+
+// Ensure items which aren't marked as unstable can't re-export unstable items
+#[stable(feature = "lint_stability", since = "1.0.0")]
+pub use lint_stability::unstable as unstable2;
+//~^ ERROR use of unstable library feature 'unstable_test_feature'
+
+fn main() {
+    // Since we didn't enable the feature in this crate, we still can't
+    // use these items, even though they're in scope from the `use`s which are now allowed.
+    unstable(); //~ ERROR use of unstable library feature 'unstable_test_feature'
+    unstable_text(); //~ ERROR use of unstable library feature 'unstable_test_feature'
+}

src/test/ui/stability-attribute/allow-unstable-reexport.stderr

@@ -0,0 +1,27 @@
+error[E0658]: use of unstable library feature 'unstable_test_feature'
+  --> $DIR/allow-unstable-reexport.rs:22:9
+   |
+LL | pub use lint_stability::unstable as unstable2;
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = help: add `#![feature(unstable_test_feature)]` to the crate attributes to enable
+
+error[E0658]: use of unstable library feature 'unstable_test_feature'
+  --> $DIR/allow-unstable-reexport.rs:28:5
+   |
+LL |     unstable();
+   |     ^^^^^^^^
+   |
+   = help: add `#![feature(unstable_test_feature)]` to the crate attributes to enable
+
+error[E0658]: use of unstable library feature 'unstable_test_feature': text
+  --> $DIR/allow-unstable-reexport.rs:29:5
+   |
+LL |     unstable_text();
+   |     ^^^^^^^^^^^^^
+   |
+   = help: add `#![feature(unstable_test_feature)]` to the crate attributes to enable
+
+error: aborting due to 3 previous errors
+
+For more information about this error, try `rustc --explain E0658`.

src/test/ui/stability-attribute/auxiliary/lint-stability-reexport.rs

@@ -0,0 +1,9 @@
+#![crate_type = "lib"]
+#![feature(staged_api)]
+#![stable(feature = "lint_stability", since = "1.0.0")]
+
+extern crate lint_stability;
+
+// Re-exporting without enabling the feature "unstable_test_feature" in this crate
+#[unstable(feature = "unstable_test_feature", issue = "none")]
+pub use lint_stability::unstable_text;

src/test/ui/unsized/issue-97732.rs

@@ -0,0 +1,28 @@
+// check-pass
+
+#![feature(coerce_unsized)]
+
+// Ensure that unsizing structs that contain ZSTs at non-zero offsets don't ICE
+
+use std::ops::CoerceUnsized;
+
+#[repr(C)]
+pub struct BoxWithZstTail<T: ?Sized>(Box<T>, ());
+
+impl<S: ?Sized, T: ?Sized> CoerceUnsized<BoxWithZstTail<T>> for BoxWithZstTail<S> where
+    Box<S>: CoerceUnsized<Box<T>>
+{
+}
+
+pub fn noop_dyn_upcast_with_zst_tail(
+    b: BoxWithZstTail<dyn ToString + Send>,
+) -> BoxWithZstTail<dyn ToString> {
+    b
+}
+
+fn main() {
+    let original = "foo";
+    let boxed = BoxWithZstTail(Box::new(original) as Box<dyn ToString + Send>, ());
+    let noop_upcasted = noop_dyn_upcast_with_zst_tail(boxed);
+    assert_eq!(original, noop_upcasted.0.to_string());
+}