Add more checks for `unnamed_field` during HIR analysis

3 files changed, 124 insertions, 0 deletions

diff --git a/tests/ui/union/unnamed-fields/auxiliary/dep.rs b/tests/ui/union/unnamed-fields/auxiliary/dep.rs
new file mode 100644
index 00000000000..a11f3e18f52
--- /dev/null
+++ b/tests/ui/union/unnamed-fields/auxiliary/dep.rs
@@ -0,0 +1,18 @@
+#[repr(C)]
+pub struct GoodStruct(());
+
+pub struct BadStruct(());
+
+pub enum BadEnum {
+    A,
+    B,
+}
+
+#[repr(C)]
+pub enum BadEnum2 {
+    A,
+    B,
+}
+
+pub type GoodAlias = GoodStruct;
+pub type BadAlias = i32;
diff --git a/tests/ui/union/unnamed-fields/restrict_type_hir.rs b/tests/ui/union/unnamed-fields/restrict_type_hir.rs
new file mode 100644
index 00000000000..80e4608be82
--- /dev/null
+++ b/tests/ui/union/unnamed-fields/restrict_type_hir.rs
@@ -0,0 +1,44 @@
+//@ aux-build:dep.rs
+
+// test for #121151
+
+#![allow(incomplete_features)]
+#![feature(unnamed_fields)]
+
+extern crate dep;
+
+#[repr(C)]
+struct A {
+    a: u8,
+}
+
+enum BadEnum {
+    A,
+    B,
+}
+
+#[repr(C)]
+enum BadEnum2 {
+    A,
+    B,
+}
+
+type MyStruct = A;
+type MyI32 = i32;
+
+#[repr(C)]
+struct L {
+    _: i32, //~ ERROR unnamed fields can only have struct or union types
+    _: MyI32, //~ ERROR unnamed fields can only have struct or union types
+    _: BadEnum, //~ ERROR unnamed fields can only have struct or union types
+    _: BadEnum2, //~ ERROR unnamed fields can only have struct or union types
+    _: MyStruct,
+    _: dep::BadStruct, //~ ERROR named type of unnamed field must have `#[repr(C)]` representation
+    _: dep::BadEnum, //~ ERROR unnamed fields can only have struct or union types
+    _: dep::BadEnum2, //~ ERROR unnamed fields can only have struct or union types
+    _: dep::BadAlias, //~ ERROR unnamed fields can only have struct or union types
+    _: dep::GoodAlias,
+    _: dep::GoodStruct,
+}
+
+fn main() {}
diff --git a/tests/ui/union/unnamed-fields/restrict_type_hir.stderr b/tests/ui/union/unnamed-fields/restrict_type_hir.stderr
new file mode 100644
index 00000000000..3e80d7fbf5c
--- /dev/null
+++ b/tests/ui/union/unnamed-fields/restrict_type_hir.stderr
@@ -0,0 +1,62 @@
+error: unnamed fields can only have struct or union types
+  --> $DIR/restrict_type_hir.rs:31:5
+   |
+LL |     _: i32,
+   |     ^^^^^^
+
+error: unnamed fields can only have struct or union types
+  --> $DIR/restrict_type_hir.rs:32:5
+   |
+LL |     _: MyI32,
+   |     ^^^^^^^^
+
+error: unnamed fields can only have struct or union types
+  --> $DIR/restrict_type_hir.rs:33:5
+   |
+LL |     _: BadEnum,
+   |     ^^^^^^^^^^
+
+error: unnamed fields can only have struct or union types
+  --> $DIR/restrict_type_hir.rs:34:5
+   |
+LL |     _: BadEnum2,
+   |     ^^^^^^^^^^^
+
+error: named type of unnamed field must have `#[repr(C)]` representation
+  --> $DIR/restrict_type_hir.rs:36:5
+   |
+LL |     _: dep::BadStruct,
+   |     ^^^^^^^^^^^^^^^^^ unnamed field defined here
+   |
+  ::: $DIR/auxiliary/dep.rs:4:1
+   |
+LL | pub struct BadStruct(());
+   | -------------------- `BadStruct` defined here
+   |
+help: add `#[repr(C)]` to this struct
+  --> $DIR/auxiliary/dep.rs:4:1
+   |
+LL + #[repr(C)]
+LL | pub struct BadStruct(());
+   |
+
+error: unnamed fields can only have struct or union types
+  --> $DIR/restrict_type_hir.rs:37:5
+   |
+LL |     _: dep::BadEnum,
+   |     ^^^^^^^^^^^^^^^
+
+error: unnamed fields can only have struct or union types
+  --> $DIR/restrict_type_hir.rs:38:5
+   |
+LL |     _: dep::BadEnum2,
+   |     ^^^^^^^^^^^^^^^^
+
+error: unnamed fields can only have struct or union types
+  --> $DIR/restrict_type_hir.rs:39:5
+   |
+LL |     _: dep::BadAlias,
+   |     ^^^^^^^^^^^^^^^^
+
+error: aborting due to 8 previous errors
+