1 files changed, 39 insertions, 0 deletions
diff --git a/tests/ui/myriad-closures.rs b/tests/ui/myriad-closures.rs
new file mode 100644
index 000000000..310351f50
--- /dev/null
+++ b/tests/ui/myriad-closures.rs
@@ -0,0 +1,39 @@
+// run-pass
+// This test case tests whether we can handle code bases that contain a high
+// number of closures, something that needs special handling in the MingGW
+// toolchain.
+// See https://github.com/rust-lang/rust/issues/34793 for more information.
+
+// Make sure we don't optimize anything away:
+// compile-flags: -C no-prepopulate-passes -Cpasses=name-anon-globals
+
+// Expand something exponentially
+macro_rules! go_bacterial {
+    ($mac:ident) => ($mac!());
+    ($mac:ident 1 $($t:tt)*) => (
+        go_bacterial!($mac $($t)*);
+        go_bacterial!($mac $($t)*);
+    )
+}
+
+macro_rules! mk_closure {
+    () => ((move || {})())
+}
+
+macro_rules! mk_fn {
+    () => {
+        {
+            fn function() {
+                // Make 16 closures
+                go_bacterial!(mk_closure 1 1 1 1);
+            }
+            let _ = function();
+        }
+    }
+}
+
+fn main() {
+    // Make 2^8 functions, each containing 16 closures,
+    // resulting in 2^12 closures overall.
+    go_bacterial!(mk_fn 1 1 1 1  1 1 1 1);
+}