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-rw-r--r--src/test/ui/regions/regions-variance-covariant-use-covariant.rs23
1 files changed, 23 insertions, 0 deletions
diff --git a/src/test/ui/regions/regions-variance-covariant-use-covariant.rs b/src/test/ui/regions/regions-variance-covariant-use-covariant.rs
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index 000000000..c5c80ce54
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+++ b/src/test/ui/regions/regions-variance-covariant-use-covariant.rs
@@ -0,0 +1,23 @@
+// run-pass
+#![allow(dead_code)]
+// Test that a type which is covariant with respect to its region
+// parameter is successful when used in a covariant way.
+//
+// Note: see ui/variance/variance-regions-*.rs for the tests that
+// check that the variance inference works in the first place.
+
+// This is covariant with respect to 'a, meaning that
+// Covariant<'foo> <: Covariant<'static> because
+// 'foo <= 'static
+// pretty-expanded FIXME #23616
+
+struct Covariant<'a> {
+ f: extern "Rust" fn(&'a isize)
+}
+
+fn use_<'a>(c: Covariant<'a>) {
+ // OK Because Covariant<'a> <: Covariant<'static> iff 'a <= 'static
+ let _: Covariant<'static> = c;
+}
+
+pub fn main() {}