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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-17 12:19:13 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-17 12:19:13 +0000
commit218caa410aa38c29984be31a5229b9fa717560ee (patch)
treec54bd55eeb6e4c508940a30e94c0032fbd45d677 /tests/ui/regions/regions-variance-invariant-use-covariant.rs
parentReleasing progress-linux version 1.67.1+dfsg1-1~progress7.99u1. (diff)
downloadrustc-218caa410aa38c29984be31a5229b9fa717560ee.tar.xz
rustc-218caa410aa38c29984be31a5229b9fa717560ee.zip
Merging upstream version 1.68.2+dfsg1.
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'tests/ui/regions/regions-variance-invariant-use-covariant.rs')
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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() { }