/// ```
#[inline]
#[stable(feature = "needs_drop", since = "1.21.0")]
+#[cfg(not(stage0))]
+pub const fn needs_drop<T>() -> bool {
+ intrinsics::needs_drop::<T>()
+}
+
+#[inline]
+#[stable(feature = "needs_drop", since = "1.21.0")]
+#[cfg(stage0)]
+/// Ceci n'est pas la documentation
pub fn needs_drop<T>() -> bool {
unsafe { intrinsics::needs_drop::<T>() }
}
match &self.item_name(def_id).as_str()[..] {
| "size_of"
| "min_align_of"
+ | "needs_drop"
=> return true,
_ => {},
}
self.write_scalar(align_val, dest)?;
}
+ "needs_drop" => {
+ let ty = substs.type_at(0);
+ let ty_needs_drop = ty.needs_drop(self.tcx.tcx, self.param_env);
+ let val = Scalar::from_bool(ty_needs_drop);
+ self.write_scalar(val, dest)?;
+ }
+
"size_of" => {
let ty = substs.type_at(0);
let size = self.layout_of(ty)?.size.bytes() as u128;
match &self.tcx.item_name(def_id).as_str()[..] {
| "size_of"
| "min_align_of"
+ | "needs_drop"
| "type_id"
| "bswap"
| "bitreverse"
(0, Vec::new(), tcx.types.never, hir::Unsafety::Unsafe)
} else {
let unsafety = match &name[..] {
- "size_of" | "min_align_of" => hir::Unsafety::Normal,
+ "size_of" | "min_align_of" | "needs_drop" => hir::Unsafety::Normal,
_ => hir::Unsafety::Unsafe,
};
let (n_tps, inputs, output) = match &name[..] {
) -> ty::PolyFnSig<'tcx> {
let unsafety = if abi == abi::Abi::RustIntrinsic {
match &*tcx.item_name(def_id).as_str() {
- "size_of" | "min_align_of" => hir::Unsafety::Normal,
+ "size_of" | "min_align_of" | "needs_drop" => hir::Unsafety::Normal,
_ => hir::Unsafety::Unsafe,
}
} else {
--- /dev/null
+// Copyright 2018 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+use std::mem;
+
+struct Trivial(u8, f32);
+
+struct NonTrivial(u8, String);
+
+const CONST_U8: bool = mem::needs_drop::<u8>();
+const CONST_STRING: bool = mem::needs_drop::<String>();
+const CONST_TRIVIAL: bool = mem::needs_drop::<Trivial>();
+const CONST_NON_TRIVIAL: bool = mem::needs_drop::<NonTrivial>();
+
+static STATIC_U8: bool = mem::needs_drop::<u8>();
+static STATIC_STRING: bool = mem::needs_drop::<String>();
+static STATIC_TRIVIAL: bool = mem::needs_drop::<Trivial>();
+static STATIC_NON_TRIVIAL: bool = mem::needs_drop::<NonTrivial>();
+
+fn main() {
+ assert!(!CONST_U8);
+ assert!(CONST_STRING);
+ assert!(!CONST_TRIVIAL);
+ assert!(CONST_NON_TRIVIAL);
+
+ assert!(!STATIC_U8);
+ assert!(STATIC_STRING);
+ assert!(!STATIC_TRIVIAL);
+ assert!(STATIC_NON_TRIVIAL);
+}