layout::Variants::Single { .. } => bug!(),
layout::Variants::Tagged { ref tag, .. } => {
let signed = match tag.value {
- layout::Int(_, signed) => signed,
+ // We use `i1` for bytes that are always `0` or `1`,
+ // e.g. `#[repr(i8)] enum E { A, B }`, but we can't
+ // let LLVM interpret the `i1` as signed, because
+ // then `i1 1` (i.e. E::B) is effectively `i8 -1`.
+ layout::Int(_, signed) => !tag.is_bool() && signed,
_ => false
};
bx.intcast(lldiscr, cast_to, signed)
let mut signed = false;
if let layout::Abi::Scalar(ref scalar) = operand.layout.abi {
if let layout::Int(_, s) = scalar.value {
- signed = s;
+ // We use `i1` for bytes that are always `0` or `1`,
+ // e.g. `#[repr(i8)] enum E { A, B }`, but we can't
+ // let LLVM interpret the `i1` as signed, because
+ // then `i1 1` (i.e. E::B) is effectively `i8 -1`.
+ signed = !scalar.is_bool() && s;
if scalar.valid_range.end() > scalar.valid_range.start() {
// We want `table[e as usize]` to not
--- /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.
+
+#![feature(core_intrinsics)]
+
+#[repr(i8)]
+pub enum Enum {
+ VariantA,
+ VariantB,
+}
+
+fn make_b() -> Enum { Enum::VariantB }
+
+fn main() {
+ assert_eq!(1, make_b() as i8);
+ assert_eq!(1, make_b() as u8);
+ assert_eq!(1, make_b() as i32);
+ assert_eq!(1, make_b() as u32);
+ assert_eq!(1, unsafe { std::intrinsics::discriminant_value(&make_b()) });
+}