[beta] backports

compiler/rustc_abi/src/extern_abi.rs

@@ -36,6 +36,10 @@ pub enum ExternAbi {
     /// Stronger than just `#[cold]` because `fn` pointers might be incompatible.
     RustCold,
 
+    /// An always-invalid ABI that's used to test "this ABI is not supported by this platform"
+    /// in a platform-agnostic way.
+    RustInvalid,
+
     /// Unstable impl detail that directly uses Rust types to describe the ABI to LLVM.
     /// Even normally-compatible Rust types can become ABI-incompatible with this ABI!
     Unadjusted,
@@ -157,6 +161,7 @@ abi_impls! {
             RiscvInterruptS =><= "riscv-interrupt-s",
             RustCall =><= "rust-call",
             RustCold =><= "rust-cold",
+            RustInvalid =><= "rust-invalid",
             Stdcall { unwind: false } =><= "stdcall",
             Stdcall { unwind: true } =><= "stdcall-unwind",
             System { unwind: false } =><= "system",

compiler/rustc_ast_lowering/src/stability.rs

@@ -96,6 +96,9 @@ pub fn extern_abi_stability(abi: ExternAbi) -> Result<(), UnstableAbi> {
         ExternAbi::RustCold => {
             Err(UnstableAbi { abi, feature: sym::rust_cold_cc, explain: GateReason::Experimental })
         }
+        ExternAbi::RustInvalid => {
+            Err(UnstableAbi { abi, feature: sym::rustc_attrs, explain: GateReason::ImplDetail })
+        }
         ExternAbi::GpuKernel => Err(UnstableAbi {
             abi,
             feature: sym::abi_gpu_kernel,

compiler/rustc_hir_typeck/src/callee.rs

@@ -156,7 +156,16 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
     pub(crate) fn check_call_abi(&self, abi: ExternAbi, span: Span) {
         let canon_abi = match AbiMap::from_target(&self.sess().target).canonize_abi(abi, false) {
             AbiMapping::Direct(canon_abi) | AbiMapping::Deprecated(canon_abi) => canon_abi,
-            AbiMapping::Invalid => return,
+            AbiMapping::Invalid => {
+                // This should be reported elsewhere, but we want to taint this body
+                // so that we don't try to evaluate calls to ABIs that are invalid.
+                let guar = self.dcx().span_delayed_bug(
+                    span,
+                    format!("invalid abi for platform should have reported an error: {abi}"),
+                );
+                self.set_tainted_by_errors(guar);
+                return;
+            }
         };
 
         let valid = match canon_abi {

compiler/rustc_middle/src/ty/layout.rs

@@ -1253,7 +1253,8 @@ pub fn fn_can_unwind(tcx: TyCtxt<'_>, fn_def_id: Option<DefId>, abi: ExternAbi)
         | CCmseNonSecureCall
         | CCmseNonSecureEntry
         | Custom
-        | Unadjusted => false,
+        | Unadjusted
+        | RustInvalid => false,
         Rust | RustCall | RustCold => tcx.sess.panic_strategy() == PanicStrategy::Unwind,
     }
 }

compiler/rustc_smir/src/rustc_internal/internal.rs

@@ -494,6 +494,7 @@ impl RustcInternal for Abi {
             Abi::RustCall => rustc_abi::ExternAbi::RustCall,
             Abi::Unadjusted => rustc_abi::ExternAbi::Unadjusted,
             Abi::RustCold => rustc_abi::ExternAbi::RustCold,
+            Abi::RustInvalid => rustc_abi::ExternAbi::RustInvalid,
             Abi::RiscvInterruptM => rustc_abi::ExternAbi::RiscvInterruptM,
             Abi::RiscvInterruptS => rustc_abi::ExternAbi::RiscvInterruptS,
             Abi::Custom => rustc_abi::ExternAbi::Custom,

compiler/rustc_smir/src/rustc_smir/convert/ty.rs

@@ -877,6 +877,7 @@ impl<'tcx> Stable<'tcx> for rustc_abi::ExternAbi {
             ExternAbi::RustCall => Abi::RustCall,
             ExternAbi::Unadjusted => Abi::Unadjusted,
             ExternAbi::RustCold => Abi::RustCold,
+            ExternAbi::RustInvalid => Abi::RustInvalid,
             ExternAbi::RiscvInterruptM => Abi::RiscvInterruptM,
             ExternAbi::RiscvInterruptS => Abi::RiscvInterruptS,
             ExternAbi::Custom => Abi::Custom,

compiler/rustc_smir/src/stable_mir/ty.rs

@@ -1126,6 +1126,7 @@ pub enum Abi {
     RustCold,
     RiscvInterruptM,
     RiscvInterruptS,
+    RustInvalid,
     Custom,
 }
 

compiler/rustc_target/src/spec/abi_map.rs

@@ -156,7 +156,8 @@ impl AbiMap {
                 | ExternAbi::Msp430Interrupt
                 | ExternAbi::RiscvInterruptM
                 | ExternAbi::RiscvInterruptS
-                | ExternAbi::X86Interrupt,
+                | ExternAbi::X86Interrupt
+                | ExternAbi::RustInvalid,
                 _,
             ) => return AbiMapping::Invalid,
         };

compiler/rustc_trait_selection/src/traits/util.rs

@@ -377,6 +377,13 @@ pub fn sizedness_fast_path<'tcx>(tcx: TyCtxt<'tcx>, predicate: ty::Predicate<'tc
             _ => return false,
         };
 
+        // FIXME(sized_hierarchy): this temporarily reverts the `sized_hierarchy` feature
+        // while a proper fix for `tests/ui/sized-hierarchy/incomplete-inference-issue-143992.rs`
+        // is pending a proper fix
+        if !tcx.features().sized_hierarchy() && matches!(sizedness, SizedTraitKind::MetaSized) {
+            return true;
+        }
+
         if trait_ref.self_ty().has_trivial_sizedness(tcx, sizedness) {
             debug!("fast path -- trivial sizedness");
             return true;

src/librustdoc/clean/mod.rs

@@ -2746,7 +2746,8 @@ fn add_without_unwanted_attributes<'hir>(
                     attrs.push((Cow::Owned(attr), import_parent));
                 }
             }
-            hir::Attribute::Parsed(..) if is_inline => {
+            // FIXME: make sure to exclude `#[cfg_trace]` here when it is ported to the new parsers
+            hir::Attribute::Parsed(..) => {
                 attrs.push((Cow::Owned(attr), import_parent));
             }
             _ => {}

tests/rustdoc/attributes-re-export.rs

@@ -0,0 +1,13 @@
+// Tests that attributes are correctly copied onto a re-exported item.
+//@ edition:2021
+#![crate_name = "re_export"]
+
+//@ has 're_export/fn.thingy2.html' '//pre[@class="rust item-decl"]' '#[no_mangle]'
+pub use thingymod::thingy as thingy2;
+
+mod thingymod {
+    #[no_mangle]
+    pub fn thingy() {
+
+    }
+}

tests/ui/abi/invalid-call-abi-ctfe.rs

@@ -0,0 +1,14 @@
+// Fix for #142969 where an invalid ABI in a signature still had its call ABI computed
+// because CTFE tried to evaluate it, despite previous errors during AST-to-HIR lowering.
+
+#![feature(rustc_attrs)]
+
+const extern "rust-invalid" fn foo() {
+    //~^ ERROR `"rust-invalid"` is not a supported ABI for the current target
+    panic!()
+}
+
+const _: () = foo();
+
+
+fn main() {}

tests/ui/abi/invalid-call-abi-ctfe.stderr

@@ -0,0 +1,9 @@
+error[E0570]: `"rust-invalid"` is not a supported ABI for the current target
+  --> $DIR/invalid-call-abi-ctfe.rs:6:1
+   |
+LL | const extern "rust-invalid" fn foo() {
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error: aborting due to 1 previous error
+
+For more information about this error, try `rustc --explain E0570`.

tests/ui/abi/invalid-call-abi.rs

@@ -0,0 +1,12 @@
+// Tests the `"rustc-invalid"` ABI, which is never canonizable.
+
+#![feature(rustc_attrs)]
+
+const extern "rust-invalid" fn foo() {
+    //~^ ERROR `"rust-invalid"` is not a supported ABI for the current target
+    panic!()
+}
+
+fn main() {
+    foo();
+}

tests/ui/abi/invalid-call-abi.stderr

@@ -0,0 +1,9 @@
+error[E0570]: `"rust-invalid"` is not a supported ABI for the current target
+  --> $DIR/invalid-call-abi.rs:5:1
+   |
+LL | const extern "rust-invalid" fn foo() {
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error: aborting due to 1 previous error
+
+For more information about this error, try `rustc --explain E0570`.

tests/ui/consts/const-size_of_val-align_of_val-extern-type.rs

@@ -8,8 +8,8 @@ extern "C" {
 }
 
 const _SIZE: usize = unsafe { size_of_val(&4 as *const i32 as *const Opaque) };
-//~^ ERROR the size for values of type `Opaque` cannot be known
+//~^ ERROR `extern type` does not have known layout
 const _ALIGN: usize = unsafe { align_of_val(&4 as *const i32 as *const Opaque) };
-//~^ ERROR the size for values of type `Opaque` cannot be known
+//~^ ERROR `extern type` does not have known layout
 
 fn main() {}

tests/ui/consts/const-size_of_val-align_of_val-extern-type.stderr

@@ -1,27 +1,15 @@
-error[E0277]: the size for values of type `Opaque` cannot be known
-  --> $DIR/const-size_of_val-align_of_val-extern-type.rs:10:43
+error[E0080]: `extern type` does not have known layout
+  --> $DIR/const-size_of_val-align_of_val-extern-type.rs:10:31
    |
 LL | const _SIZE: usize = unsafe { size_of_val(&4 as *const i32 as *const Opaque) };
-   |                               ----------- ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ doesn't have a known size
-   |                               |
-   |                               required by a bound introduced by this call
-   |
-   = help: the trait `MetaSized` is not implemented for `Opaque`
-note: required by a bound in `std::intrinsics::size_of_val`
-  --> $SRC_DIR/core/src/intrinsics/mod.rs:LL:COL
+   |                               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ evaluation of `_SIZE` failed here
 
-error[E0277]: the size for values of type `Opaque` cannot be known
-  --> $DIR/const-size_of_val-align_of_val-extern-type.rs:12:45
+error[E0080]: `extern type` does not have known layout
+  --> $DIR/const-size_of_val-align_of_val-extern-type.rs:12:32
    |
 LL | const _ALIGN: usize = unsafe { align_of_val(&4 as *const i32 as *const Opaque) };
-   |                                ------------ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ doesn't have a known size
-   |                                |
-   |                                required by a bound introduced by this call
-   |
-   = help: the trait `MetaSized` is not implemented for `Opaque`
-note: required by a bound in `std::intrinsics::align_of_val`
-  --> $SRC_DIR/core/src/intrinsics/mod.rs:LL:COL
+   |                                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ evaluation of `_ALIGN` failed here
 
 error: aborting due to 2 previous errors
 
-For more information about this error, try `rustc --explain E0277`.
+For more information about this error, try `rustc --explain E0080`.

tests/ui/extern/extern-types-size_of_val.rs

@@ -1,4 +1,4 @@
-//@ check-fail
+//@ check-pass
 #![feature(extern_types)]
 
 use std::mem::{align_of_val, size_of_val};
@@ -11,7 +11,5 @@ fn main() {
     let x: &A = unsafe { &*(1usize as *const A) };
 
     size_of_val(x);
-    //~^ ERROR the size for values of type `A` cannot be known
     align_of_val(x);
-    //~^ ERROR the size for values of type `A` cannot be known
 }

tests/ui/extern/extern-types-unsized.rs

@@ -27,9 +27,7 @@ fn main() {
 
     assert_sized::<Bar<A>>();
     //~^ ERROR the size for values of type
-    //~| ERROR the size for values of type
 
     assert_sized::<Bar<Bar<A>>>();
     //~^ ERROR the size for values of type
-    //~| ERROR the size for values of type
 }

tests/ui/extern/extern-types-unsized.stderr

@@ -59,21 +59,8 @@ help: consider relaxing the implicit `Sized` restriction
 LL | fn assert_sized<T: ?Sized>() {}
    |                  ++++++++
 
-error[E0277]: the size for values of type `A` cannot be known
-  --> $DIR/extern-types-unsized.rs:28:20
-   |
-LL |     assert_sized::<Bar<A>>();
-   |                    ^^^^^^ doesn't have a known size
-   |
-   = help: the trait `MetaSized` is not implemented for `A`
-note: required by a bound in `Bar`
-  --> $DIR/extern-types-unsized.rs:14:12
-   |
-LL | struct Bar<T: ?Sized> {
-   |            ^ required by this bound in `Bar`
-
 error[E0277]: the size for values of type `A` cannot be known at compilation time
-  --> $DIR/extern-types-unsized.rs:32:20
+  --> $DIR/extern-types-unsized.rs:31:20
    |
 LL |     assert_sized::<Bar<Bar<A>>>();
    |                    ^^^^^^^^^^^ doesn't have a size known at compile-time
@@ -94,19 +81,6 @@ help: consider relaxing the implicit `Sized` restriction
 LL | fn assert_sized<T: ?Sized>() {}
    |                  ++++++++
 
-error[E0277]: the size for values of type `A` cannot be known
-  --> $DIR/extern-types-unsized.rs:32:20
-   |
-LL |     assert_sized::<Bar<Bar<A>>>();
-   |                    ^^^^^^^^^^^ doesn't have a known size
-   |
-   = help: the trait `MetaSized` is not implemented for `A`
-note: required by a bound in `Bar`
-  --> $DIR/extern-types-unsized.rs:14:12
-   |
-LL | struct Bar<T: ?Sized> {
-   |            ^ required by this bound in `Bar`
-
-error: aborting due to 6 previous errors
+error: aborting due to 4 previous errors
 
 For more information about this error, try `rustc --explain E0277`.

tests/ui/extern/unsized-extern-derefmove.rs

@@ -7,14 +7,10 @@ extern "C" {
 }
 
 unsafe fn make_device() -> Box<Device> {
-//~^ ERROR the size for values of type `Device` cannot be known
     Box::from_raw(0 as *mut _)
-//~^ ERROR the size for values of type `Device` cannot be known
-//~| ERROR the size for values of type `Device` cannot be known
 }
 
 fn main() {
     let d: Device = unsafe { *make_device() };
 //~^ ERROR the size for values of type `Device` cannot be known
-//~| ERROR the size for values of type `Device` cannot be known
 }