From 00010eda8b2828da967a562c093c6723889203ae Mon Sep 17 00:00:00 2001 From: yukang Date: Sun, 3 Sep 2023 10:58:13 +0800 Subject: [PATCH] Fix error report for size overflow from transmute --- .../src/traits/error_reporting/mod.rs | 10 ++++++ compiler/rustc_transmute/src/layout/tree.rs | 3 ++ compiler/rustc_transmute/src/lib.rs | 4 +++ .../src/maybe_transmutable/mod.rs | 2 ++ .../transmute/issue-115402-overflow-size.rs | 27 +++++++++++++++ .../issue-115402-overflow-size.stderr | 33 +++++++++++++++++++ 6 files changed, 79 insertions(+) create mode 100644 tests/ui/transmute/issue-115402-overflow-size.rs create mode 100644 tests/ui/transmute/issue-115402-overflow-size.stderr diff --git a/compiler/rustc_trait_selection/src/traits/error_reporting/mod.rs b/compiler/rustc_trait_selection/src/traits/error_reporting/mod.rs index 457d5420ca3..746a38f956a 100644 --- a/compiler/rustc_trait_selection/src/traits/error_reporting/mod.rs +++ b/compiler/rustc_trait_selection/src/traits/error_reporting/mod.rs @@ -2920,6 +2920,16 @@ fn get_safe_transmute_error_and_reason( rustc_transmute::Reason::DstIsTooBig => { format!("The size of `{src}` is smaller than the size of `{dst}`") } + rustc_transmute::Reason::SrcSizeOverflow => { + format!( + "values of the type `{src}` are too big for the current architecture" + ) + } + rustc_transmute::Reason::DstSizeOverflow => { + format!( + "values of the type `{dst}` are too big for the current architecture" + ) + } rustc_transmute::Reason::DstHasStricterAlignment { src_min_align, dst_min_align, diff --git a/compiler/rustc_transmute/src/layout/tree.rs b/compiler/rustc_transmute/src/layout/tree.rs index e8ddb0a4396..49f24f66b24 100644 --- a/compiler/rustc_transmute/src/layout/tree.rs +++ b/compiler/rustc_transmute/src/layout/tree.rs @@ -189,6 +189,8 @@ pub(crate) enum Err { Unspecified, /// This error will be surfaced elsewhere by rustc, so don't surface it. UnknownLayout, + /// Overflow size + SizeOverflow, TypeError(ErrorGuaranteed), } @@ -196,6 +198,7 @@ impl<'tcx> From<&LayoutError<'tcx>> for Err { fn from(err: &LayoutError<'tcx>) -> Self { match err { LayoutError::Unknown(..) | LayoutError::ReferencesError(..) => Self::UnknownLayout, + LayoutError::SizeOverflow(..) => Self::SizeOverflow, err => unimplemented!("{:?}", err), } } diff --git a/compiler/rustc_transmute/src/lib.rs b/compiler/rustc_transmute/src/lib.rs index 05ad4a4a12a..af2ad547480 100644 --- a/compiler/rustc_transmute/src/lib.rs +++ b/compiler/rustc_transmute/src/lib.rs @@ -64,6 +64,10 @@ pub enum Reason { SrcLayoutUnknown, /// The layout of dst is unknown DstLayoutUnknown, + /// The size of src is overflow + SrcSizeOverflow, + /// The size of dst is overflow + DstSizeOverflow, } #[cfg(feature = "rustc")] diff --git a/compiler/rustc_transmute/src/maybe_transmutable/mod.rs b/compiler/rustc_transmute/src/maybe_transmutable/mod.rs index b223a90f751..c0141f1f841 100644 --- a/compiler/rustc_transmute/src/maybe_transmutable/mod.rs +++ b/compiler/rustc_transmute/src/maybe_transmutable/mod.rs @@ -85,6 +85,8 @@ pub fn answer(self) -> Answer< as QueryContext>::Ref> { (_, Err(Err::UnknownLayout)) => Answer::No(Reason::DstLayoutUnknown), (Err(Err::Unspecified), _) => Answer::No(Reason::SrcIsUnspecified), (_, Err(Err::Unspecified)) => Answer::No(Reason::DstIsUnspecified), + (Err(Err::SizeOverflow), _) => Answer::No(Reason::SrcSizeOverflow), + (_, Err(Err::SizeOverflow)) => Answer::No(Reason::DstSizeOverflow), (Ok(src), Ok(dst)) => { MaybeTransmutableQuery { src, dst, scope, assume, context }.answer() } diff --git a/tests/ui/transmute/issue-115402-overflow-size.rs b/tests/ui/transmute/issue-115402-overflow-size.rs new file mode 100644 index 00000000000..91168041ed6 --- /dev/null +++ b/tests/ui/transmute/issue-115402-overflow-size.rs @@ -0,0 +1,27 @@ +#![crate_type = "lib"] +#![feature(transmutability)] +mod assert { + use std::mem::BikeshedIntrinsicFrom; + struct Context; + + pub fn is_maybe_transmutable() + where + Dst: BikeshedIntrinsicFrom, + { + } +} + +fn main() { + pub union Uninit { + a: [u8; usize::MAX], + } + + #[repr(C)] + struct ExplicitlyPadded(Uninit); + + assert::is_maybe_transmutable::<(), ExplicitlyPadded>(); + //~^ ERROR `()` cannot be safely transmuted into `ExplicitlyPadded` + + assert::is_maybe_transmutable::(); + //~^ ERROR `ExplicitlyPadded` cannot be safely transmuted into `()` +} diff --git a/tests/ui/transmute/issue-115402-overflow-size.stderr b/tests/ui/transmute/issue-115402-overflow-size.stderr new file mode 100644 index 00000000000..08d180f6427 --- /dev/null +++ b/tests/ui/transmute/issue-115402-overflow-size.stderr @@ -0,0 +1,33 @@ +error[E0277]: `()` cannot be safely transmuted into `ExplicitlyPadded` in the defining scope of `assert::Context` + --> $DIR/issue-115402-overflow-size.rs:22:41 + | +LL | assert::is_maybe_transmutable::<(), ExplicitlyPadded>(); + | ^^^^^^^^^^^^^^^^ values of the type `ExplicitlyPadded` are too big for the current architecture + | +note: required by a bound in `is_maybe_transmutable` + --> $DIR/issue-115402-overflow-size.rs:9:14 + | +LL | pub fn is_maybe_transmutable() + | --------------------- required by a bound in this function +LL | where +LL | Dst: BikeshedIntrinsicFrom, + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ required by this bound in `is_maybe_transmutable` + +error[E0277]: `ExplicitlyPadded` cannot be safely transmuted into `()` in the defining scope of `assert::Context` + --> $DIR/issue-115402-overflow-size.rs:25:55 + | +LL | assert::is_maybe_transmutable::(); + | ^^ values of the type `ExplicitlyPadded` are too big for the current architecture + | +note: required by a bound in `is_maybe_transmutable` + --> $DIR/issue-115402-overflow-size.rs:9:14 + | +LL | pub fn is_maybe_transmutable() + | --------------------- required by a bound in this function +LL | where +LL | Dst: BikeshedIntrinsicFrom, + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ required by this bound in `is_maybe_transmutable` + +error: aborting due to 2 previous errors + +For more information about this error, try `rustc --explain E0277`.