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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-17 12:19:50 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-17 12:19:50 +0000
commit2e00214b3efbdfeefaa0fe9e8b8fd519de7adc35 (patch)
treed325add32978dbdc1db975a438b3a77d571b1ab8 /tests/ui/derives/deriving-with-repr-packed.rs
parentReleasing progress-linux version 1.68.2+dfsg1-1~progress7.99u1. (diff)
downloadrustc-2e00214b3efbdfeefaa0fe9e8b8fd519de7adc35.tar.xz
rustc-2e00214b3efbdfeefaa0fe9e8b8fd519de7adc35.zip
Merging upstream version 1.69.0+dfsg1.
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'tests/ui/derives/deriving-with-repr-packed.rs')
-rw-r--r--tests/ui/derives/deriving-with-repr-packed.rs53
1 files changed, 27 insertions, 26 deletions
diff --git a/tests/ui/derives/deriving-with-repr-packed.rs b/tests/ui/derives/deriving-with-repr-packed.rs
index 3884e3977..58be45197 100644
--- a/tests/ui/derives/deriving-with-repr-packed.rs
+++ b/tests/ui/derives/deriving-with-repr-packed.rs
@@ -1,45 +1,46 @@
-#![deny(unaligned_references)]
-
// Check that deriving certain builtin traits on certain packed structs cause
-// errors. This happens when the derived trait would need to use a potentially
-// misaligned reference. But there are two cases that are allowed:
-// - If all the fields within the struct meet the required alignment: 1 for
-// `repr(packed)`, or `N` for `repr(packed(N))`.
-// - If `Default` is the only trait derived, because it doesn't involve any
-// references.
+// errors. To avoid potentially misaligned references, field copies must be
+// used, which involves adding `T: Copy` bounds.
#[derive(Copy, Clone, Default, PartialEq, Eq)]
-//~^ ERROR `Clone` can't be derived on this `#[repr(packed)]` struct with type or const parameters
-//~| hard error
-//~^^^ ERROR `PartialEq` can't be derived on this `#[repr(packed)]` struct with type or const parameters
-//~| hard error
#[repr(packed)]
pub struct Foo<T>(T, T, T);
+// This one is fine because the fields all impl `Copy`.
#[derive(Default, Hash)]
-//~^ ERROR `Hash` can't be derived on this `#[repr(packed)]` struct that does not derive `Copy`
-//~| hard error
#[repr(packed)]
pub struct Bar(u32, u32, u32);
-// This one is fine because the field alignment is 1.
-#[derive(Default, Hash)]
-#[repr(packed)]
-pub struct Bar2(u8, i8, bool);
-
-// This one is fine because the field alignment is 2, matching `packed(2)`.
-#[derive(Default, Hash)]
-#[repr(packed(2))]
-pub struct Bar3(u16, i16, bool);
-
// This one is fine because it's not packed.
#[derive(Debug, Default)]
struct Y(usize);
+// This one has an error because `Y` doesn't impl `Copy`.
+// Note: there is room for improvement in the error message.
#[derive(Debug, Default)]
-//~^ ERROR `Debug` can't be derived on this `#[repr(packed)]` struct that does not derive `Copy`
-//~| hard error
#[repr(packed)]
struct X(Y);
+//~^ ERROR cannot move out of `self` which is behind a shared reference
+
+// This is currently allowed, but will be phased out at some point. From
+// `zerovec` within icu4x-0.9.0.
+#[derive(Debug)]
+#[repr(packed)]
+struct FlexZeroSlice {
+ width: u8,
+ data: [u8],
+ //~^ WARNING byte slice in a packed struct that derives a built-in trait
+ //~^^ this was previously accepted
+}
+
+// Again, currently allowed, but will be phased out.
+#[derive(Debug)]
+#[repr(packed)]
+struct WithStr {
+ width: u8,
+ data: str,
+ //~^ WARNING string slice in a packed struct that derives a built-in trait
+ //~^^ this was previously accepted
+}
fn main() {}