1 files changed, 397 insertions, 0 deletions
diff --git a/tests/ui/intrinsics/panic-uninitialized-zeroed.rs b/tests/ui/intrinsics/panic-uninitialized-zeroed.rs
new file mode 100644
index 000000000..1a0104b85
--- /dev/null
+++ b/tests/ui/intrinsics/panic-uninitialized-zeroed.rs
@@ -0,0 +1,397 @@
+// run-pass
+// revisions: default strict
+// [strict]compile-flags: -Zstrict-init-checks
+// ignore-tidy-linelength
+// ignore-emscripten spawning processes is not supported
+// ignore-sgx no processes
+
+// This test checks panic emitted from `mem::{uninitialized,zeroed}`.
+
+#![feature(never_type)]
+#![allow(deprecated, invalid_value)]
+
+use std::{
+    mem::{self, MaybeUninit, ManuallyDrop},
+    ptr::NonNull,
+    num,
+};
+
+#[allow(dead_code)]
+struct Foo {
+    x: u8,
+    y: !,
+}
+
+enum Bar {}
+
+#[allow(dead_code)]
+enum OneVariant { Variant(i32) }
+
+#[allow(dead_code, non_camel_case_types)]
+enum OneVariant_NonZero {
+    Variant(i32, i32, num::NonZeroI32),
+    DeadVariant(Bar),
+}
+
+#[allow(dead_code, non_camel_case_types)]
+enum OneVariant_Ref {
+    Variant(&'static i32),
+    DeadVariant(Bar),
+}
+
+// An `Aggregate` abi enum where 0 is not a valid discriminant.
+#[allow(dead_code)]
+#[repr(i32)]
+enum NoNullVariant {
+    Variant1(i32, i32) = 1,
+    Variant2(i32, i32) = 2,
+}
+
+// An enum with ScalarPair layout
+#[allow(dead_code)]
+enum LR {
+    Left(i64),
+    Right(i64),
+}
+#[allow(dead_code, non_camel_case_types)]
+enum LR_NonZero {
+    Left(num::NonZeroI64),
+    Right(num::NonZeroI64),
+}
+
+struct ZeroSized;
+
+#[allow(dead_code)]
+#[repr(i32)]
+enum ZeroIsValid {
+    Zero(u8) = 0,
+    One(NonNull<()>) = 1,
+}
+
+#[track_caller]
+fn test_panic_msg<T, F: (FnOnce() -> T) + 'static>(op: F, msg: &str) {
+    use std::{panic, env, process};
+
+    // The tricky part is that we can't just run `op`, as that would *abort* the process.
+    // So instead, we reinvoke this process with the caller location as argument.
+    // For the purpose of this test, the line number is unique enough.
+    // If we are running in such a re-invocation, we skip all the tests *except* for the one with that type name.
+    let our_loc = panic::Location::caller().line().to_string();
+    let mut args = env::args();
+    let this = args.next().unwrap();
+    if let Some(loc) = args.next() {
+        if loc == our_loc {
+            op();
+            panic!("we did not abort");
+        } else {
+            // Nothing, we are running another test.
+        }
+    } else {
+        // Invoke new process for actual test, and check result.
+        let mut cmd = process::Command::new(this);
+        cmd.arg(our_loc);
+        let res = cmd.output().unwrap();
+        assert!(!res.status.success(), "test did not fail");
+        let stderr = String::from_utf8_lossy(&res.stderr);
+        assert!(stderr.contains(msg), "test did not contain expected output: looking for {:?}, output:\n{}", msg, stderr);
+    }
+}
+
+#[track_caller]
+fn test_panic_msg_only_if_strict<T>(op: impl (FnOnce() -> T) + 'static, msg: &str) {
+    if !cfg!(strict) {
+        // Just run it.
+        op();
+    } else {
+        test_panic_msg(op, msg);
+    }
+}
+
+fn main() {
+    unsafe {
+        // Uninhabited types
+        test_panic_msg(
+            || mem::uninitialized::<!>(),
+            "attempted to instantiate uninhabited type `!`"
+        );
+        test_panic_msg(
+            || mem::zeroed::<!>(),
+            "attempted to instantiate uninhabited type `!`"
+        );
+        test_panic_msg(
+            || MaybeUninit::<!>::uninit().assume_init(),
+            "attempted to instantiate uninhabited type `!`"
+        );
+
+        test_panic_msg(
+            || mem::uninitialized::<Foo>(),
+            "attempted to instantiate uninhabited type `Foo`"
+        );
+        test_panic_msg(
+            || mem::zeroed::<Foo>(),
+            "attempted to instantiate uninhabited type `Foo`"
+        );
+        test_panic_msg(
+            || MaybeUninit::<Foo>::uninit().assume_init(),
+            "attempted to instantiate uninhabited type `Foo`"
+        );
+
+        test_panic_msg(
+            || mem::uninitialized::<Bar>(),
+            "attempted to instantiate uninhabited type `Bar`"
+        );
+        test_panic_msg(
+            || mem::zeroed::<Bar>(),
+            "attempted to instantiate uninhabited type `Bar`"
+        );
+        test_panic_msg(
+            || MaybeUninit::<Bar>::uninit().assume_init(),
+            "attempted to instantiate uninhabited type `Bar`"
+        );
+
+        test_panic_msg(
+            || mem::uninitialized::<[Foo; 2]>(),
+            "attempted to instantiate uninhabited type `[Foo; 2]`"
+        );
+        test_panic_msg(
+            || mem::zeroed::<[Foo; 2]>(),
+            "attempted to instantiate uninhabited type `[Foo; 2]`"
+        );
+        test_panic_msg(
+            || MaybeUninit::<[Foo; 2]>::uninit().assume_init(),
+            "attempted to instantiate uninhabited type `[Foo; 2]`"
+        );
+
+        test_panic_msg(
+            || mem::uninitialized::<[Bar; 2]>(),
+            "attempted to instantiate uninhabited type `[Bar; 2]`"
+        );
+        test_panic_msg(
+            || mem::zeroed::<[Bar; 2]>(),
+            "attempted to instantiate uninhabited type `[Bar; 2]`"
+        );
+        test_panic_msg(
+            || MaybeUninit::<[Bar; 2]>::uninit().assume_init(),
+            "attempted to instantiate uninhabited type `[Bar; 2]`"
+        );
+
+        // Types that don't allow either.
+        test_panic_msg(
+            || mem::zeroed::<&i32>(),
+            "attempted to zero-initialize type `&i32`, which is invalid"
+        );
+        test_panic_msg(
+            || mem::uninitialized::<&i32>(),
+            "attempted to leave type `&i32` uninitialized, which is invalid"
+        );
+
+        test_panic_msg(
+            || mem::zeroed::<Box<[i32; 0]>>(),
+            "attempted to zero-initialize type `alloc::boxed::Box<[i32; 0]>`, which is invalid"
+        );
+        test_panic_msg(
+            || mem::uninitialized::<Box<[i32; 0]>>(),
+            "attempted to leave type `alloc::boxed::Box<[i32; 0]>` uninitialized, which is invalid"
+        );
+
+        test_panic_msg(
+            || mem::zeroed::<Box<u8>>(),
+            "attempted to zero-initialize type `alloc::boxed::Box<u8>`, which is invalid"
+        );
+        test_panic_msg(
+            || mem::uninitialized::<Box<u8>>(),
+            "attempted to leave type `alloc::boxed::Box<u8>` uninitialized, which is invalid"
+        );
+
+        test_panic_msg(
+            || mem::zeroed::<&[i32]>(),
+            "attempted to zero-initialize type `&[i32]`, which is invalid"
+        );
+        test_panic_msg(
+            || mem::uninitialized::<&[i32]>(),
+            "attempted to leave type `&[i32]` uninitialized, which is invalid"
+        );
+
+        test_panic_msg(
+            || mem::zeroed::<&(u8, [u8])>(),
+            "attempted to zero-initialize type `&(u8, [u8])`, which is invalid"
+        );
+        test_panic_msg(
+            || mem::uninitialized::<&(u8, [u8])>(),
+            "attempted to leave type `&(u8, [u8])` uninitialized, which is invalid"
+        );
+
+        test_panic_msg(
+            || mem::zeroed::<&dyn Send>(),
+            "attempted to zero-initialize type `&dyn core::marker::Send`, which is invalid"
+        );
+        test_panic_msg(
+            || mem::uninitialized::<&dyn Send>(),
+            "attempted to leave type `&dyn core::marker::Send` uninitialized, which is invalid"
+        );
+
+        test_panic_msg(
+            || mem::zeroed::<*const dyn Send>(),
+            "attempted to zero-initialize type `*const dyn core::marker::Send`, which is invalid"
+        );
+        test_panic_msg(
+            || mem::uninitialized::<*const dyn Send>(),
+            "attempted to leave type `*const dyn core::marker::Send` uninitialized, which is invalid"
+        );
+
+        test_panic_msg(
+            || mem::uninitialized::<NoNullVariant>(),
+            "attempted to leave type `NoNullVariant` uninitialized, \
+                which is invalid"
+        );
+        test_panic_msg(
+            || mem::zeroed::<NoNullVariant>(),
+            "attempted to zero-initialize type `NoNullVariant`, \
+                which is invalid"
+        );
+
+        test_panic_msg(
+            || mem::zeroed::<OneVariant_Ref>(),
+            "attempted to zero-initialize type `OneVariant_Ref`, \
+                which is invalid"
+        );
+        test_panic_msg(
+            || mem::uninitialized::<OneVariant_Ref>(),
+            "attempted to leave type `OneVariant_Ref` uninitialized, which is invalid"
+        );
+
+        // Types where both are invalid, but we allow uninit since the 0x01-filling is not LLVM UB.
+        test_panic_msg(
+            || mem::zeroed::<fn()>(),
+            "attempted to zero-initialize type `fn()`, which is invalid"
+        );
+        test_panic_msg_only_if_strict(
+            || mem::uninitialized::<fn()>(),
+            "attempted to leave type `fn()` uninitialized, which is invalid"
+        );
+
+        test_panic_msg(
+            || mem::zeroed::<&()>(),
+            "attempted to zero-initialize type `&()`, which is invalid"
+        );
+        test_panic_msg_only_if_strict(
+            || mem::uninitialized::<&()>(),
+            "attempted to leave type `&()` uninitialized, which is invalid"
+        );
+
+        test_panic_msg(
+            || mem::zeroed::<&[u8]>(),
+            "attempted to zero-initialize type `&[u8]`, which is invalid"
+        );
+        test_panic_msg_only_if_strict(
+            || mem::uninitialized::<&[u8]>(),
+            "attempted to leave type `&[u8]` uninitialized, which is invalid"
+        );
+
+        test_panic_msg(
+            || mem::zeroed::<&str>(),
+            "attempted to zero-initialize type `&str`, which is invalid"
+        );
+        test_panic_msg_only_if_strict(
+            || mem::uninitialized::<&str>(),
+            "attempted to leave type `&str` uninitialized, which is invalid"
+        );
+
+        test_panic_msg(
+            || mem::zeroed::<(NonNull<u32>, u32, u32)>(),
+            "attempted to zero-initialize type `(core::ptr::non_null::NonNull<u32>, u32, u32)`, \
+                which is invalid"
+        );
+        test_panic_msg_only_if_strict(
+            || mem::uninitialized::<(NonNull<u32>, u32, u32)>(),
+            "attempted to leave type `(core::ptr::non_null::NonNull<u32>, u32, u32)` uninitialized, which is invalid"
+        );
+
+        test_panic_msg(
+            || mem::zeroed::<OneVariant_NonZero>(),
+            "attempted to zero-initialize type `OneVariant_NonZero`, \
+                which is invalid"
+        );
+        test_panic_msg_only_if_strict(
+            || mem::uninitialized::<OneVariant_NonZero>(),
+            "attempted to leave type `OneVariant_NonZero` uninitialized, which is invalid"
+        );
+
+        // Types where both are invalid but we allow the zeroed form since it is not LLVM UB.
+        test_panic_msg_only_if_strict(
+            || mem::zeroed::<LR_NonZero>(),
+            "attempted to zero-initialize type `LR_NonZero`, which is invalid"
+        );
+        test_panic_msg(
+            || mem::uninitialized::<LR_NonZero>(),
+            "attempted to leave type `LR_NonZero` uninitialized, which is invalid"
+        );
+
+        test_panic_msg_only_if_strict(
+            || mem::zeroed::<ManuallyDrop<LR_NonZero>>(),
+            "attempted to zero-initialize type `core::mem::manually_drop::ManuallyDrop<LR_NonZero>`, \
+             which is invalid"
+        );
+        test_panic_msg(
+            || mem::uninitialized::<ManuallyDrop<LR_NonZero>>(),
+            "attempted to leave type `core::mem::manually_drop::ManuallyDrop<LR_NonZero>` uninitialized, \
+             which is invalid"
+        );
+
+        // Some strict-only things
+        test_panic_msg_only_if_strict(
+            || mem::uninitialized::<i32>(),
+            "attempted to leave type `i32` uninitialized, which is invalid"
+        );
+
+        test_panic_msg_only_if_strict(
+            || mem::uninitialized::<*const ()>(),
+            "attempted to leave type `*const ()` uninitialized, which is invalid"
+        );
+
+        test_panic_msg_only_if_strict(
+            || mem::uninitialized::<[i32; 1]>(),
+            "attempted to leave type `[i32; 1]` uninitialized, which is invalid"
+        );
+
+        test_panic_msg_only_if_strict(
+            || mem::zeroed::<[NonNull<()>; 1]>(),
+            "attempted to zero-initialize type `[core::ptr::non_null::NonNull<()>; 1]`, which is invalid"
+        );
+
+        // Types that can be zero, but not uninit (though some are mitigated).
+        let _val = mem::zeroed::<LR>();
+        test_panic_msg(
+            || mem::uninitialized::<LR>(),
+            "attempted to leave type `LR` uninitialized, which is invalid"
+        );
+
+        let _val = mem::zeroed::<ManuallyDrop<LR>>();
+        test_panic_msg(
+            || mem::uninitialized::<ManuallyDrop<LR>>(),
+            "attempted to leave type `core::mem::manually_drop::ManuallyDrop<LR>` uninitialized, which is invalid"
+        );
+
+        let _val = mem::zeroed::<bool>();
+        test_panic_msg_only_if_strict(
+            || mem::uninitialized::<bool>(),
+            "attempted to leave type `bool` uninitialized, which is invalid"
+        );
+
+        let _val = mem::zeroed::<OneVariant>();
+        test_panic_msg_only_if_strict(
+            || mem::uninitialized::<OneVariant>(),
+            "attempted to leave type `OneVariant` uninitialized, which is invalid"
+        );
+
+        // Some things that are actually allowed.
+        let _val = mem::zeroed::<Option<&'static i32>>();
+        let _val = mem::zeroed::<MaybeUninit<NonNull<u32>>>();
+        let _val = mem::zeroed::<[!; 0]>();
+        let _val = mem::zeroed::<ZeroIsValid>();
+        let _val = mem::uninitialized::<MaybeUninit<bool>>();
+        let _val = mem::uninitialized::<[!; 0]>();
+        let _val = mem::uninitialized::<()>();
+        let _val = mem::uninitialized::<ZeroSized>();
+    }
+}