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-rw-r--r--src/test/ui/regions/regions-variance-contravariant-use-covariant.rs27
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diff --git a/src/test/ui/regions/regions-variance-contravariant-use-covariant.rs b/src/test/ui/regions/regions-variance-contravariant-use-covariant.rs
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+// Test that a type which is covariant with respect to its region
+// parameter yields an error when used in a contravariant way.
+//
+// Note: see variance-regions-*.rs for the tests that check that the
+// variance inference works in the first place.
+
+// This is contravariant with respect to 'a, meaning that
+// Contravariant<'long> <: Contravariant<'short> iff
+// 'short <= 'long
+struct Contravariant<'a> {
+ f: &'a isize
+}
+
+fn use_<'short,'long>(c: Contravariant<'short>,
+ s: &'short isize,
+ l: &'long isize,
+ _where:Option<&'short &'long ()>) {
+
+ // Test whether Contravariant<'short> <: Contravariant<'long>. Since
+ // 'short <= 'long, this would be true if the Contravariant type were
+ // covariant with respect to its parameter 'a.
+
+ let _: Contravariant<'long> = c;
+ //~^ ERROR lifetime may not live long enough
+}
+
+fn main() {}