remove move_val_init leftovers

compiler/rustc_mir/src/transform/check_unsafety.rs

@@ -223,13 +223,6 @@ impl<'a, 'tcx> Visitor<'tcx> for UnsafetyChecker<'a, 'tcx> {
         // Check for raw pointer `Deref`.
         for (base, proj) in place.iter_projections() {
             if proj == ProjectionElem::Deref {
-                let source_info = self.source_info; // Backup source_info so we can restore it later.
-                if base.projection.is_empty() && decl.internal {
-                    // Internal locals are used in the `move_val_init` desugaring.
-                    // We want to check unsafety against the source info of the
-                    // desugaring, rather than the source info of the RHS.
-                    self.source_info = self.body.local_decls[place.local].source_info;
-                }
                 let base_ty = base.ty(self.body, self.tcx).ty;
                 if base_ty.is_unsafe_ptr() {
                     self.require_unsafe(
@@ -237,7 +230,6 @@ impl<'a, 'tcx> Visitor<'tcx> for UnsafetyChecker<'a, 'tcx> {
                         UnsafetyViolationDetails::DerefOfRawPointer,
                     )
                 }
-                self.source_info = source_info; // Restore backed-up source_info.
             }
         }
 

compiler/rustc_mir_build/src/build/expr/into.rs

@@ -10,9 +10,7 @@ use rustc_data_structures::stack::ensure_sufficient_stack;
 use rustc_hir as hir;
 use rustc_middle::middle::region;
 use rustc_middle::mir::*;
-use rustc_middle::ty::{self, CanonicalUserTypeAnnotation};
+use rustc_middle::ty::{CanonicalUserTypeAnnotation};
-use rustc_span::symbol::sym;
-use rustc_target::spec::abi::Abi;
 
 use std::slice;
 
@@ -185,45 +183,8 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
                     },
                 )
             }
-            ExprKind::Call { ty, fun, args, from_hir_call, fn_span } => {
+            ExprKind::Call { ty: _, fun, args, from_hir_call, fn_span } => {
-                let intrinsic = match *ty.kind() {
-                    ty::FnDef(def_id, _) => {
-                        let f = ty.fn_sig(this.hir.tcx());
-                        if f.abi() == Abi::RustIntrinsic || f.abi() == Abi::PlatformIntrinsic {
-                            Some(this.hir.tcx().item_name(def_id))
-                        } else {
-                            None
-                        }
-                    }
-                    _ => None,
-                };
                 let fun = unpack!(block = this.as_local_operand(block, fun));
-                if let Some(sym::move_val_init) = intrinsic {
-                    // `move_val_init` has "magic" semantics - the second argument is
-                    // always evaluated "directly" into the first one.
-
-                    let mut args = args.into_iter();
-                    let ptr = args.next().expect("0 arguments to `move_val_init`");
-                    let val = args.next().expect("1 argument to `move_val_init`");
-                    assert!(args.next().is_none(), ">2 arguments to `move_val_init`");
-
-                    let ptr = this.hir.mirror(ptr);
-                    let ptr_ty = ptr.ty;
-                    // Create an *internal* temp for the pointer, so that unsafety
-                    // checking won't complain about the raw pointer assignment.
-                    let ptr_temp = this
-                        .local_decls
-                        .push(LocalDecl::with_source_info(ptr_ty, source_info).internal());
-                    let ptr_temp = Place::from(ptr_temp);
-                    // No need for a scope, ptr_temp doesn't need drop
-                    let block = unpack!(this.into(ptr_temp, None, block, ptr));
-                    // Maybe we should provide a scope here so that
-                    // `move_val_init` wouldn't leak on panic even with an
-                    // arbitrary `val` expression, but `schedule_drop`,
-                    // borrowck and drop elaboration all prevent us from
-                    // dropping `ptr_temp.deref()`.
-                    this.into(this.hir.tcx().mk_place_deref(ptr_temp), None, block, val)
-                } else {
                 let args: Vec<_> = args
                     .into_iter()
                     .map(|arg| unpack!(block = this.as_local_call_operand(block, arg)))
@@ -258,7 +219,6 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
                 schedule_drop(this);
                 success.unit()
             }
-            }
             ExprKind::Use { source } => this.into(destination, scope, block, source),
             ExprKind::Borrow { arg, borrow_kind } => {
                 // We don't do this in `as_rvalue` because we use `as_place`

compiler/rustc_span/src/symbol.rs

@@ -713,7 +713,6 @@ symbols! {
         more_struct_aliases,
         movbe_target_feature,
         move_ref_pattern,
-        move_val_init,
         mul,
         mul_assign,
         mul_with_overflow,

compiler/rustc_typeck/src/check/intrinsic.rs

@@ -159,7 +159,6 @@ pub fn check_intrinsic_type(tcx: TyCtxt<'_>, it: &hir::ForeignItem<'_>) {
             }
             sym::forget => (1, vec![param(0)], tcx.mk_unit()),
             sym::transmute => (2, vec![param(0)], param(1)),
-            sym::move_val_init => (1, vec![tcx.mk_mut_ptr(param(0)), param(0)], tcx.mk_unit()),
             sym::prefetch_read_data
             | sym::prefetch_write_data
             | sym::prefetch_read_instruction

src/test/codegen/intrinsics/move-val-init.rs

@@ -1,19 +0,0 @@
-// compile-flags: -C no-prepopulate-passes
-
-#![feature(core_intrinsics)]
-#![crate_type = "lib"]
-
-// test that `move_val_init` actually avoids big allocas
-
-use std::intrinsics::move_val_init;
-
-pub struct Big {
-    pub data: [u8; 65536]
-}
-
-// CHECK-LABEL: @test_mvi
-#[no_mangle]
-pub unsafe fn test_mvi(target: *mut Big, make_big: fn() -> Big) {
-    // CHECK: call void %make_big(%Big*{{[^%]*}} %target)
-    move_val_init(target, make_big());
-}

src/test/ui/intrinsics/intrinsic-move-val-cleanups.rs

@@ -1,191 +0,0 @@
-// run-pass
-#![allow(unused_braces)]
-#![allow(unused_unsafe)]
-#![allow(unreachable_code)]
-// ignore-emscripten no threads support
-#![allow(stable_features)]
-
-// This test is checking that the move_val_init intrinsic is
-// respecting cleanups for both of its argument expressions.
-//
-// In other words, if either DEST or SOURCE in
-//
-//   `intrinsics::move_val_init(DEST, SOURCE)
-//
-// introduce temporaries that require cleanup, and SOURCE panics, then
-// make sure the cleanups still occur.
-
-#![feature(core_intrinsics, sync_poison)]
-
-use std::cell::RefCell;
-use std::intrinsics;
-use std::sync::{Arc, LockResult, Mutex, MutexGuard};
-use std::thread;
-
-type LogEntry = (&'static str, i32);
-type Guarded = RefCell<Vec<LogEntry>>;
-#[derive(Clone)]
-struct Log(Arc<Mutex<Guarded>>);
-struct Acquired<'a>(MutexGuard<'a, Guarded>);
-type LogState = (MutexWas, &'static [LogEntry]);
-
-#[derive(Copy, Clone, PartialEq, Eq, Debug)]
-enum MutexWas { Poisoned, NotPoisoned }
-
-impl Log {
-    fn lock(&self) -> LockResult<MutexGuard<RefCell<Vec<LogEntry>>>> { self.0.lock() }
-    fn acquire(&self) -> Acquired { Acquired(self.0.lock().unwrap()) }
-}
-
-impl<'a> Acquired<'a> {
-    fn log(&self, s: &'static str, i: i32) { self.0.borrow_mut().push((s, i)); }
-}
-
-const TEST1_EXPECT: LogState = (MutexWas::NotPoisoned,
-                                &[("double-check non-poisoning path", 1)
-                                  ]);
-
-fn test1(log: Log) {
-    {
-        let acq = log.acquire();
-        acq.log("double-check non-poisoning path", 1);
-    }
-    panic!("every test ends in a panic");
-}
-
-const TEST2_EXPECT: LogState = (MutexWas::Poisoned,
-                                &[("double-check poisoning path", 1),
-                                  ("and multiple log entries", 2),
-                                  ]);
-fn test2(log: Log) {
-    let acq = log.acquire();
-    acq.log("double-check poisoning path", 1);
-    acq.log("and multiple log entries", 2);
-    panic!("every test ends in a panic");
-}
-
-struct LogOnDrop<'a>(&'a Acquired<'a>, &'static str, i32);
-impl<'a> Drop for LogOnDrop<'a> {
-    fn drop(&mut self) {
-        self.0.log(self.1, self.2);
-    }
-}
-
-const TEST3_EXPECT: LogState = (MutexWas::Poisoned,
-                                &[("double-check destructors can log", 1),
-                                  ("drop d2", 2),
-                                  ("drop d1", 3),
-                                  ]);
-fn test3(log: Log) {
-    let acq = log.acquire();
-    acq.log("double-check destructors can log", 1);
-    let _d1 = LogOnDrop(&acq, "drop d1", 3);
-    let _d2 = LogOnDrop(&acq, "drop d2", 2);
-    panic!("every test ends in a panic");
-}
-
-// The *real* tests of panic-handling for move_val_init intrinsic
-// start here.
-
-const TEST4_EXPECT: LogState = (MutexWas::Poisoned,
-                                &[("neither arg panics", 1),
-                                  ("drop temp LOD", 2),
-                                  ("drop temp LOD", 3),
-                                  ("drop dest_b", 4),
-                                  ("drop dest_a", 5),
-                                  ]);
-fn test4(log: Log) {
-    let acq = log.acquire();
-    acq.log("neither arg panics", 1);
-    let mut dest_a = LogOnDrop(&acq, "a will be overwritten, not dropped", 0);
-    let mut dest_b = LogOnDrop(&acq, "b will be overwritten, not dropped", 0);
-    unsafe {
-        intrinsics::move_val_init({ LogOnDrop(&acq, "drop temp LOD", 2); &mut dest_a },
-                                  LogOnDrop(&acq, "drop dest_a", 5));
-        intrinsics::move_val_init(&mut dest_b, { LogOnDrop(&acq, "drop temp LOD", 3);
-                                                 LogOnDrop(&acq, "drop dest_b", 4) });
-    }
-    panic!("every test ends in a panic");
-}
-
-
-// Check that move_val_init(PANIC, SOURCE_EXPR) never evaluates SOURCE_EXPR
-const TEST5_EXPECT: LogState = (MutexWas::Poisoned,
-                                &[("first arg panics", 1),
-                                  ("drop orig dest_a", 2),
-                                  ]);
-fn test5(log: Log) {
-    let acq = log.acquire();
-    acq.log("first arg panics", 1);
-    let mut _dest_a = LogOnDrop(&acq, "drop orig dest_a", 2);
-    unsafe {
-        intrinsics::move_val_init({ panic!("every test ends in a panic") },
-                                  LogOnDrop(&acq, "we never get here", 0));
-    }
-}
-
-// Check that move_val_init(DEST_EXPR, PANIC) cleans up temps from DEST_EXPR.
-const TEST6_EXPECT: LogState = (MutexWas::Poisoned,
-                                &[("second arg panics", 1),
-                                  ("drop temp LOD", 2),
-                                  ("drop orig dest_a", 3),
-                                  ]);
-fn test6(log: Log) {
-    let acq = log.acquire();
-    acq.log("second arg panics", 1);
-    let mut dest_a = LogOnDrop(&acq, "drop orig dest_a", 3);
-    unsafe {
-        intrinsics::move_val_init({ LogOnDrop(&acq, "drop temp LOD", 2); &mut dest_a },
-                                  { panic!("every test ends in a panic"); });
-    }
-}
-
-// Check that move_val_init(DEST_EXPR, COMPLEX_PANIC) cleans up temps from COMPLEX_PANIC.
-const TEST7_EXPECT: LogState = (MutexWas::Poisoned,
-                                &[("second arg panics", 1),
-                                  ("drop temp LOD", 2),
-                                  ("drop temp LOD", 3),
-                                  ("drop orig dest_a", 4),
-                                  ]);
-fn test7(log: Log) {
-    let acq = log.acquire();
-    acq.log("second arg panics", 1);
-    let mut dest_a = LogOnDrop(&acq, "drop orig dest_a", 4);
-    unsafe {
-        intrinsics::move_val_init({ LogOnDrop(&acq, "drop temp LOD", 2); &mut dest_a },
-                                  { LogOnDrop(&acq, "drop temp LOD", 3);
-                                    panic!("every test ends in a panic"); });
-    }
-}
-
-const TEST_SUITE: &'static [(&'static str, fn (Log), LogState)] =
-    &[("test1", test1, TEST1_EXPECT),
-      ("test2", test2, TEST2_EXPECT),
-      ("test3", test3, TEST3_EXPECT),
-      ("test4", test4, TEST4_EXPECT),
-      ("test5", test5, TEST5_EXPECT),
-      ("test6", test6, TEST6_EXPECT),
-      ("test7", test7, TEST7_EXPECT),
-      ];
-
-fn main() {
-    for &(name, test, expect) in TEST_SUITE {
-        let log = Log(Arc::new(Mutex::new(RefCell::new(Vec::new()))));
-        let ret = { let log = log.clone(); thread::spawn(move || test(log)).join() };
-        assert!(ret.is_err(), "{} must end with panic", name);
-        {
-            let l = log.lock();
-            match l {
-                Ok(acq) => {
-                    assert_eq!((MutexWas::NotPoisoned, &acq.borrow()[..]), expect);
-                    println!("{} (unpoisoned) log: {:?}", name, *acq);
-                }
-                Err(e) => {
-                    let acq = e.into_inner();
-                    assert_eq!((MutexWas::Poisoned, &acq.borrow()[..]), expect);
-                    println!("{} (poisoned) log: {:?}", name, *acq);
-                }
-            }
-        }
-    }
-}

src/test/ui/intrinsics/intrinsic-move-val.rs

@@ -1,81 +0,0 @@
-// run-pass
-
-#![feature(box_syntax)]
-#![feature(intrinsics)]
-
-mod rusti {
-    extern "rust-intrinsic" {
-        pub fn move_val_init<T>(dst: *mut T, src: T);
-    }
-}
-
-pub fn main() {
-    unsafe {
-        // sanity check
-        check_drops_state(0, None);
-
-        let mut x: Option<Box<D>> = Some(box D(1));
-        assert_eq!(x.as_ref().unwrap().0, 1);
-
-        // A normal overwrite, to demonstrate `check_drops_state`.
-        x = Some(box D(2));
-
-        // At this point, one destructor has run, because the
-        // overwrite of `x` drops its initial value.
-        check_drops_state(1, Some(1));
-
-        let mut y: Option<Box<D>> = std::mem::zeroed();
-
-        // An initial binding does not overwrite anything.
-        check_drops_state(1, Some(1));
-
-        // Since `y` has been initialized via the `init` intrinsic, it
-        // would be unsound to directly overwrite its value via normal
-        // assignment.
-        //
-        // The code currently generated by the compiler is overly
-        // accepting, however, in that it will check if `y` is itself
-        // null and thus avoid the unsound action of attempting to
-        // free null. In other words, if we were to do a normal
-        // assignment like `y = box D(4);` here, it probably would not
-        // crash today. But the plan is that it may well crash in the
-        // future, (I believe).
-
-        // `x` is moved here; the manner in which this is tracked by the
-        // compiler is hidden.
-        rusti::move_val_init(&mut y, x);
-
-        // But what we *can* observe is how many times the destructor
-        // for `D` is invoked, and what the last value we saw was
-        // during such a destructor call. We do so after the end of
-        // this scope.
-
-        assert_eq!(y.as_ref().unwrap().0, 2);
-        y.as_mut().unwrap().0 = 3;
-        assert_eq!(y.as_ref().unwrap().0, 3);
-
-        check_drops_state(1, Some(1));
-    }
-
-    check_drops_state(2, Some(3));
-}
-
-static mut NUM_DROPS: i32 = 0;
-static mut LAST_DROPPED: Option<i32> = None;
-
-fn check_drops_state(num_drops: i32, last_dropped: Option<i32>) {
-    unsafe {
-        assert_eq!(NUM_DROPS, num_drops);
-        assert_eq!(LAST_DROPPED, last_dropped);
-    }
-}
-
-struct D(i32);
-impl Drop for D {
-    fn drop(&mut self) {
-        unsafe {
-            NUM_DROPS += 1;
-            LAST_DROPPED = Some(self.0);
-        }
-    }
-}

src/test/ui/panic-handler/weak-lang-item.stderr

@@ -10,10 +10,10 @@ help: you can use `as` to change the binding name of the import
 LL | extern crate core as other_core;
    |
 
-error: `#[panic_handler]` function required, but not found
-
 error: language item required, but not found: `eh_personality`
 
+error: `#[panic_handler]` function required, but not found
+
 error: aborting due to 3 previous errors
 
 For more information about this error, try `rustc --explain E0259`.

src/test/ui/unsafe/unsafe-move-val-init.rs

@@ -1,10 +0,0 @@
-#![feature(core_intrinsics)]
-
-use std::intrinsics;
-
-// `move_val_init` has an odd desugaring, check that it is still treated
-// as unsafe.
-fn main() {
-    intrinsics::move_val_init(1 as *mut u32, 1);
-    //~^ ERROR dereference of raw pointer is unsafe
-}

src/test/ui/unsafe/unsafe-move-val-init.stderr

@@ -1,11 +0,0 @@
-error[E0133]: dereference of raw pointer is unsafe and requires unsafe function or block
-  --> $DIR/unsafe-move-val-init.rs:8:5
-   |
-LL |     intrinsics::move_val_init(1 as *mut u32, 1);
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ dereference of raw pointer
-   |
-   = note: raw pointers may be NULL, dangling or unaligned; they can violate aliasing rules and cause data races: all of these are undefined behavior
-
-error: aborting due to previous error
-
-For more information about this error, try `rustc --explain E0133`.