diff options
Diffstat (limited to 'tests/ui/regions/regions-free-region-ordering-callee.rs')
-rw-r--r-- | tests/ui/regions/regions-free-region-ordering-callee.rs | 30 |
1 files changed, 30 insertions, 0 deletions
diff --git a/tests/ui/regions/regions-free-region-ordering-callee.rs b/tests/ui/regions/regions-free-region-ordering-callee.rs new file mode 100644 index 000000000..8158e81e1 --- /dev/null +++ b/tests/ui/regions/regions-free-region-ordering-callee.rs @@ -0,0 +1,30 @@ +// Tests that callees correctly infer an ordering between free regions +// that appear in their parameter list. See also +// regions-free-region-ordering-caller.rs + +fn ordering1<'a, 'b>(x: &'a &'b usize) -> &'a usize { + // It is safe to assume that 'a <= 'b due to the type of x + let y: &'b usize = &**x; + return y; +} + +fn ordering2<'a, 'b>(x: &'a &'b usize, y: &'a usize) -> &'b usize { + // However, it is not safe to assume that 'b <= 'a + &*y + //~^ ERROR lifetime may not live long enough +} + +fn ordering3<'a, 'b>(x: &'a usize, y: &'b usize) -> &'a &'b usize { + // Do not infer an ordering from the return value. + let z: &'b usize = &*x; + //~^ ERROR lifetime may not live long enough + panic!(); +} + +// see regions-free-region-ordering-callee-4.rs + +fn ordering5<'a, 'b>(a: &'a usize, b: &'b usize, x: Option<&'a &'b usize>) { + let z: Option<&'a &'b usize> = None; +} + +fn main() {} |