2 files changed, 16 insertions, 0 deletions
diff --git a/src/test/ui/suggestions/undeclared-module-alloc.rs b/src/test/ui/suggestions/undeclared-module-alloc.rs
new file mode 100644
index 00000000000..1defa1cef28
--- /dev/null
+++ b/src/test/ui/suggestions/undeclared-module-alloc.rs
@@ -0,0 +1,5 @@
+// edition:2018
+
+use alloc::rc::Rc; //~ ERROR failed to resolve: use of undeclared crate or module `alloc`
+
+fn main() {}
diff --git a/src/test/ui/suggestions/undeclared-module-alloc.stderr b/src/test/ui/suggestions/undeclared-module-alloc.stderr
new file mode 100644
index 00000000000..39169dfa9f7
--- /dev/null
+++ b/src/test/ui/suggestions/undeclared-module-alloc.stderr
@@ -0,0 +1,11 @@
+error[E0433]: failed to resolve: use of undeclared crate or module `alloc`
+  --> $DIR/undeclared-module-alloc.rs:3:5
+   |
+LL | use alloc::rc::Rc;
+   |     ^^^^^ use of undeclared crate or module `alloc`
+   |
+   = help: add `extern crate alloc` to use the `alloc` crate
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0433`.