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-rw-r--r--tests/ui/regions/regions-variance-invariant-use-covariant.rs21
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diff --git a/tests/ui/regions/regions-variance-invariant-use-covariant.rs b/tests/ui/regions/regions-variance-invariant-use-covariant.rs
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+// Test that a type which is invariant with respect to its region
+// parameter used in a covariant way yields an error.
+//
+// Note: see variance-regions-*.rs for the tests that check that the
+// variance inference works in the first place.
+
+struct Invariant<'a> {
+ f: &'a mut &'a isize
+}
+
+fn use_<'b>(c: Invariant<'b>) {
+
+ // For this assignment to be legal, Invariant<'b> <: Invariant<'static>.
+ // Since 'b <= 'static, this would be true if Invariant were covariant
+ // with respect to its parameter 'a.
+
+ let _: Invariant<'static> = c;
+ //~^ ERROR lifetime may not live long enough
+}
+
+fn main() { }