1 files changed, 22 insertions, 0 deletions
diff --git a/src/test/ui/borrowck/assign_mutable_fields.rs b/src/test/ui/borrowck/assign_mutable_fields.rs
new file mode 100644
index 000000000..b60726d0c
--- /dev/null
+++ b/src/test/ui/borrowck/assign_mutable_fields.rs
@@ -0,0 +1,22 @@
+// Currently, we do permit you to assign to individual fields of an
+// uninitialized var.
+// We hope to fix this at some point.
+//
+// FIXME(#54987)
+
+fn assign_both_fields_and_use() {
+    let mut x: (u32, u32);
+    x.0 = 1; //~ ERROR
+    x.1 = 22;
+    drop(x.0);
+    drop(x.1);
+}
+
+fn assign_both_fields_the_use_var() {
+    let mut x: (u32, u32);
+    x.0 = 1; //~ ERROR
+    x.1 = 22;
+    drop(x);
+}
+
+fn main() { }