Added tests for discriminant overflows.

src/test/compile-fail/discrim-ill-typed.rs

@@ -0,0 +1,118 @@
+// Copyright 2015 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.
+
+// When explicit discriminant value has
+// a type that does not match the representation
+// type, rustc should fail gracefully.
+
+// See also run-pass/discrim-explicit-23030.rs where the input types
+// are correct.
+
+#![allow(dead_code, unused_variables, unused_imports)]
+
+use std::{i8,u8,i16,u16,i32,u32,i64, u64};
+
+fn f_i8() {
+    #[repr(i8)]
+    enum A {
+        Ok = i8::MAX - 1,
+        Ok2,
+        OhNo = 0_u8,
+        //~^ ERROR mismatched types
+    }
+
+    let x = A::Ok;
+}
+
+fn f_u8() {
+    #[repr(u8)]
+    enum A {
+        Ok = u8::MAX - 1,
+        Ok2,
+        OhNo = 0_i8,
+        //~^  ERROR mismatched types
+    }
+
+    let x = A::Ok;
+}
+
+fn f_i16() {
+    #[repr(i16)]
+    enum A {
+        Ok = i16::MAX - 1,
+        Ok2,
+        OhNo = 0_u16,
+        //~^ ERROR mismatched types
+    }
+
+    let x = A::Ok;
+}
+
+fn f_u16() {
+    #[repr(u16)]
+    enum A {
+        Ok = u16::MAX - 1,
+        Ok2,
+        OhNo = 0_i16,
+        //~^ ERROR mismatched types
+    }
+
+    let x = A::Ok;
+}
+
+fn f_i32() {
+    #[repr(i32)]
+    enum A {
+        Ok = i32::MAX - 1,
+        Ok2,
+        OhNo = 0_u32,
+        //~^ ERROR mismatched types
+    }
+
+    let x = A::Ok;
+}
+
+fn f_u32() {
+    #[repr(u32)]
+    enum A {
+        Ok = u32::MAX - 1,
+        Ok2,
+        OhNo = 0_i32,
+        //~^ ERROR mismatched types
+    }
+
+    let x = A::Ok;
+}
+
+fn f_i64() {
+    #[repr(i64)]
+    enum A {
+        Ok = i64::MAX - 1,
+        Ok2,
+        OhNo = 0_u64,
+        //~^ ERROR mismatched types
+    }
+
+    let x = A::Ok;
+}
+
+fn f_u64() {
+    #[repr(u64)]
+    enum A {
+        Ok = u64::MAX - 1,
+        Ok2,
+        OhNo = 0_i64,
+        //~^ ERROR mismatched types
+    }
+
+    let x = A::Ok;
+}
+
+fn main() { }

src/test/compile-fail/discrim-overflow-2.rs

@@ -0,0 +1,94 @@
+// Copyright 2015 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.
+
+// ignore-tidy-linelength
+
+// Issue 23030: Detect overflowing discriminant
+//
+// Check that we detect the overflow even if enum is not used.
+
+// See also run-pass/discrim-explicit-23030.rs where the suggested
+// workaround is tested.
+
+use std::{i8,u8,i16,u16,i32,u32,i64, u64};
+
+fn f_i8() {
+    #[repr(i8)]
+    enum A {
+        Ok = i8::MAX - 1,
+        Ok2,
+        OhNo, //~ ERROR enum discriminant overflowed on value after 127: i8; set explicitly via OhNo = -128 if that is desired outcome
+    }
+}
+
+fn f_u8() {
+    #[repr(u8)]
+    enum A {
+        Ok = u8::MAX - 1,
+        Ok2,
+        OhNo, //~ ERROR enum discriminant overflowed on value after 255: u8; set explicitly via OhNo = 0 if that is desired outcome
+    }
+}
+
+fn f_i16() {
+    #[repr(i16)]
+    enum A {
+        Ok = i16::MAX - 1,
+        Ok2,
+        OhNo, //~ ERROR enum discriminant overflowed
+    }
+}
+
+fn f_u16() {
+    #[repr(u16)]
+    enum A {
+        Ok = u16::MAX - 1,
+        Ok2,
+        OhNo, //~ ERROR enum discriminant overflowed
+    }
+}
+
+fn f_i32() {
+    #[repr(i32)]
+    enum A {
+        Ok = i32::MAX - 1,
+        Ok2,
+        OhNo, //~ ERROR enum discriminant overflowed
+    }
+}
+
+fn f_u32() {
+    #[repr(u32)]
+    enum A {
+        Ok = u32::MAX - 1,
+        Ok2,
+        OhNo, //~ ERROR enum discriminant overflowed
+    }
+}
+
+fn f_i64() {
+    #[repr(i64)]
+    enum A {
+        Ok = i64::MAX - 1,
+        Ok2,
+        OhNo, //~ ERROR enum discriminant overflowed
+    }
+}
+
+fn f_u64() {
+    #[repr(u64)]
+    enum A {
+        Ok = u64::MAX - 1,
+        Ok2,
+        OhNo, //~ ERROR enum discriminant overflowed
+    }
+}
+
+fn main() { }

src/test/compile-fail/discrim-overflow.rs

@@ -0,0 +1,108 @@
+// Copyright 2015 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.
+
+// ignore-tidy-linelength
+
+// Issue 23030: Detect overflowing discriminant
+
+// See also run-pass/discrim-explicit-23030.rs where the suggested
+// workaround is tested.
+
+use std::{i8,u8,i16,u16,i32,u32,i64, u64};
+
+fn f_i8() {
+    #[repr(i8)]
+    enum A {
+        Ok = i8::MAX - 1,
+        Ok2,
+        OhNo, //~ ERROR enum discriminant overflowed on value after 127: i8; set explicitly via OhNo = -128 if that is desired outcome
+    }
+
+    let x = A::Ok;
+}
+
+fn f_u8() {
+    #[repr(u8)]
+    enum A {
+        Ok = u8::MAX - 1,
+        Ok2,
+        OhNo, //~ ERROR enum discriminant overflowed on value after 255: u8; set explicitly via OhNo = 0 if that is desired outcome
+    }
+
+    let x = A::Ok;
+}
+
+fn f_i16() {
+    #[repr(i16)]
+    enum A {
+        Ok = i16::MAX - 1,
+        Ok2,
+        OhNo, //~ ERROR enum discriminant overflowed
+    }
+
+    let x = A::Ok;
+}
+
+fn f_u16() {
+    #[repr(u16)]
+    enum A {
+        Ok = u16::MAX - 1,
+        Ok2,
+        OhNo, //~ ERROR enum discriminant overflowed
+    }
+
+    let x = A::Ok;
+}
+
+fn f_i32() {
+    #[repr(i32)]
+    enum A {
+        Ok = i32::MAX - 1,
+        Ok2,
+        OhNo, //~ ERROR enum discriminant overflowed
+    }
+
+    let x = A::Ok;
+}
+
+fn f_u32() {
+    #[repr(u32)]
+    enum A {
+        Ok = u32::MAX - 1,
+        Ok2,
+        OhNo, //~ ERROR enum discriminant overflowed
+    }
+
+    let x = A::Ok;
+}
+
+fn f_i64() {
+    #[repr(i64)]
+    enum A {
+        Ok = i64::MAX - 1,
+        Ok2,
+        OhNo, //~ ERROR enum discriminant overflowed
+    }
+
+    let x = A::Ok;
+}
+
+fn f_u64() {
+    #[repr(u64)]
+    enum A {
+        Ok = u64::MAX - 1,
+        Ok2,
+        OhNo, //~ ERROR enum discriminant overflowed
+    }
+
+    let x = A::Ok;
+}
+
+fn main() { }

src/test/run-pass/discrim-explicit-23030.rs

@@ -0,0 +1,156 @@
+// Copyright 2015 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.
+
+// Issue 23030: Workaround overflowing discriminant
+// with explicit assignments.
+
+// See also compile-fail/overflow-discrim.rs, which shows what
+// happens if you leave the OhNo explicit cases out here.
+
+use std::{i8,u8,i16,u16,i32,u32,i64,u64,isize,usize};
+
+fn f_i8() {
+    #[repr(i8)]
+    enum A {
+        Ok = i8::MAX - 1,
+        Ok2,
+        OhNo = i8::MIN,
+        NotTheEnd = -1,
+        Zero,
+    }
+
+    let _x = (A::Ok, A::Ok2, A::OhNo);
+    let z = (A::NotTheEnd, A::Zero).1 as i8;
+    assert_eq!(z, 0);
+}
+
+fn f_u8() {
+    #[repr(u8)]
+    enum A {
+        Ok = u8::MAX - 1,
+        Ok2,
+        OhNo = u8::MIN,
+    }
+
+    let _x = (A::Ok, A::Ok2, A::OhNo);
+}
+
+fn f_i16() {
+    #[repr(i16)]
+    enum A {
+        Ok = i16::MAX - 1,
+        Ok2,
+        OhNo = i16::MIN,
+        NotTheEnd = -1,
+        Zero,
+    }
+
+    let _x = (A::Ok, A::Ok2, A::OhNo);
+    let z = (A::NotTheEnd, A::Zero).1 as i16;
+    assert_eq!(z, 0);
+}
+
+fn f_u16() {
+    #[repr(u16)]
+    enum A {
+        Ok = u16::MAX - 1,
+        Ok2,
+        OhNo = u16::MIN,
+    }
+
+    let _x = (A::Ok, A::Ok2, A::OhNo);
+}
+
+fn f_i32() {
+    #[repr(i32)]
+    enum A {
+        Ok = i32::MAX - 1,
+        Ok2,
+        OhNo = i32::MIN,
+        NotTheEnd = -1,
+        Zero,
+    }
+
+    let _x = (A::Ok, A::Ok2, A::OhNo);
+    let z = (A::NotTheEnd, A::Zero).1 as i32;
+    assert_eq!(z, 0);
+}
+
+fn f_u32() {
+    #[repr(u32)]
+    enum A {
+        Ok = u32::MAX - 1,
+        Ok2,
+        OhNo = u32::MIN,
+    }
+
+    let _x = (A::Ok, A::Ok2, A::OhNo);
+}
+
+fn f_i64() {
+    #[repr(i64)]
+    enum A {
+        Ok = i64::MAX - 1,
+        Ok2,
+        OhNo = i64::MIN,
+        NotTheEnd = -1,
+        Zero,
+    }
+
+    let _x = (A::Ok, A::Ok2, A::OhNo);
+    let z = (A::NotTheEnd, A::Zero).1 as i64;
+    assert_eq!(z, 0);
+}
+
+fn f_u64() {
+    #[repr(u64)]
+    enum A {
+        Ok = u64::MAX - 1,
+        Ok2,
+        OhNo = u64::MIN,
+    }
+
+    let _x = (A::Ok, A::Ok2, A::OhNo);
+}
+
+fn f_isize() {
+    #[repr(isize)]
+    enum A {
+        Ok = isize::MAX - 1,
+        Ok2,
+        OhNo = isize::MIN,
+        NotTheEnd = -1,
+        Zero,
+    }
+
+    let _x = (A::Ok, A::Ok2, A::OhNo);
+    let z = (A::NotTheEnd, A::Zero).1 as isize;
+    assert_eq!(z, 0);
+}
+
+fn f_usize() {
+    #[repr(usize)]
+    enum A {
+        Ok = usize::MAX - 1,
+        Ok2,
+        OhNo = usize::MIN,
+    }
+
+    let _x = (A::Ok, A::Ok2, A::OhNo);
+}
+
+fn main() {
+    f_i8(); f_u8();
+    f_i16(); f_u16();
+    f_i32(); f_u32();
+    f_i64(); f_u64();
+
+    f_isize(); f_usize();
+}