Use ignore/keep-wasm32 where appropriate.

src/test/ui/imports/empty-extern-arg-wasm.rs

@@ -0,0 +1,5 @@
+// compile-flags: --extern std=
+// error-pattern: can't find crate for `std`
+// only-wasm32
+
+fn main() {}

src/test/ui/imports/empty-extern-arg-wasm.stderr

@@ -0,0 +1,9 @@
+error: extern location for std does not exist: 
+
+error[E0463]: can't find crate for `std`
+   |
+   = note: the `wasm32-unknown-unknown` target may not be installed
+
+error: aborting due to 2 previous errors
+
+For more information about this error, try `rustc --explain E0463`.

src/test/ui/imports/empty-extern-arg.rs

@@ -1,4 +1,5 @@
 // compile-flags: --extern std=
 // error-pattern: can't find crate for `std`
+// ignore-wasm32
 
 fn main() {}

src/test/ui/thread-local/issue-43733-2-wasm.rs

@@ -0,0 +1,30 @@
+// only-wasm32
+
+#![feature(cfg_target_thread_local, thread_local_internals)]
+
+// On platforms *without* `#[thread_local]`, use
+// a custom non-`Sync` type to fake the same error.
+#[cfg(not(target_thread_local))]
+struct Key<T> {
+    _data: std::cell::UnsafeCell<Option<T>>,
+    _flag: std::cell::Cell<()>,
+}
+
+#[cfg(not(target_thread_local))]
+impl<T> Key<T> {
+    const fn new() -> Self {
+        Key {
+            _data: std::cell::UnsafeCell::new(None),
+            _flag: std::cell::Cell::new(()),
+        }
+    }
+}
+
+#[cfg(target_thread_local)]
+use std::thread::__FastLocalKeyInner as Key;
+
+static __KEY: Key<()> = Key::new();
+//~^ ERROR `std::cell::UnsafeCell<std::option::Option<()>>` cannot be shared between threads
+//~| ERROR cannot be shared between threads safely [E0277]
+
+fn main() {}

src/test/ui/thread-local/issue-43733-2-wasm.stderr

@@ -0,0 +1,23 @@
+error[E0277]: `std::cell::UnsafeCell<std::option::Option<()>>` cannot be shared between threads safely
+  --> $DIR/issue-43733-2-wasm.rs:26:1
+   |
+LL | static __KEY: Key<()> = Key::new();
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `std::cell::UnsafeCell<std::option::Option<()>>` cannot be shared between threads safely
+   |
+   = help: within `Key<()>`, the trait `std::marker::Sync` is not implemented for `std::cell::UnsafeCell<std::option::Option<()>>`
+   = note: required because it appears within the type `Key<()>`
+   = note: shared static variables must have a type that implements `Sync`
+
+error[E0277]: `std::cell::Cell<()>` cannot be shared between threads safely
+  --> $DIR/issue-43733-2-wasm.rs:26:1
+   |
+LL | static __KEY: Key<()> = Key::new();
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `std::cell::Cell<()>` cannot be shared between threads safely
+   |
+   = help: within `Key<()>`, the trait `std::marker::Sync` is not implemented for `std::cell::Cell<()>`
+   = note: required because it appears within the type `Key<()>`
+   = note: shared static variables must have a type that implements `Sync`
+
+error: aborting due to 2 previous errors
+
+For more information about this error, try `rustc --explain E0277`.

src/test/ui/thread-local/issue-43733-2.rs

@@ -1,3 +1,5 @@
+// ignore-wasm32
+
 #![feature(cfg_target_thread_local, thread_local_internals)]
 
 // On platforms *without* `#[thread_local]`, use

src/test/ui/thread-local/issue-43733-2.stderr

@@ -1,5 +1,5 @@
 error[E0277]: `std::cell::Cell<std::thread::local::fast::DtorState>` cannot be shared between threads safely
-  --> $DIR/issue-43733-2.rs:24:1
+  --> $DIR/issue-43733-2.rs:26:1
    |
 LL | static __KEY: Key<()> = Key::new();
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `std::cell::Cell<std::thread::local::fast::DtorState>` cannot be shared between threads safely
@@ -9,7 +9,7 @@ LL | static __KEY: Key<()> = Key::new();
    = note: shared static variables must have a type that implements `Sync`
 
 error[E0277]: `std::cell::UnsafeCell<std::option::Option<()>>` cannot be shared between threads safely
-  --> $DIR/issue-43733-2.rs:24:1
+  --> $DIR/issue-43733-2.rs:26:1
    |
 LL | static __KEY: Key<()> = Key::new();
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `std::cell::UnsafeCell<std::option::Option<()>>` cannot be shared between threads safely