Merge pull request rust-lang#278 from solson/unions

Process untagged unions

Author: eddyb

.travis.yml

@@ -27,6 +27,11 @@ script:
 - |
   # and run all tests with full mir
   MIRI_SYSROOT=~/.xargo/HOST cargo test
+- |
+  # test that the rustc_tests binary compiles
+  cd rustc_tests &&
+  cargo build &&
+  cd ..
 notifications:
   email:
     on_success: never

Cargo.toml

@@ -34,4 +34,4 @@ rustc_miri = { path = "src/librustc_mir" }
 compiletest_rs = "0.2.6"
 
 [workspace]
-exclude = ["xargo", "cargo-miri-test"]
+exclude = ["xargo", "cargo-miri-test", "rustc_tests"]

miri/fn_call.rs

@@ -126,7 +126,13 @@ impl<'a, 'tcx> EvalContextExt<'tcx> for EvalContext<'a, 'tcx, super::Evaluator>
             }
 
             "syscall" => {
+                // TODO: read `syscall` ids like `sysconf` ids and
+                // figure out some way to actually process some of them
+                //
+                // libc::syscall(NR_GETRANDOM, buf.as_mut_ptr(), buf.len(), GRND_NONBLOCK)
+                // is called if a `HashMap` is created the regular way.
                 match self.value_to_primval(args[0], usize)?.to_u64()? {
+                    318 |
                     511 => return Err(EvalError::Unimplemented("miri does not support random number generators".to_owned())),
                     id => return Err(EvalError::Unimplemented(format!("miri does not support syscall id {}", id))),
                 }

rustc_tests/Cargo.lock

@@ -4,4 +4,4 @@ version = "0.1.0"
 authors = ["Oliver Schneider <[email protected]>"]
 
 [dependencies]
-miri = { path = "../miri" }
+miri = { path = ".." }

rustc_tests/Cargo.toml

@@ -149,11 +149,7 @@ fn main() {
             args.push(Path::new(&std::env::var("HOME").unwrap()).join(".xargo").join("HOST").display().to_string());
         }
 
-        // we run the optimization passes inside miri
-        // if we ran them twice we'd get funny failures due to borrowck ElaborateDrops only working on
-        // unoptimized MIR
-        // FIXME: add an after-mir-passes hook to rustc driver
-        args.push("-Zmir-opt-level=0".to_owned());
+        args.push("-Zmir-opt-level=3".to_owned());
         // for auxilary builds in unit tests
         args.push("-Zalways-encode-mir".to_owned());
 
@@ -218,7 +214,7 @@ fn main() {
             }
         }
     }
-    let stderr = std::io::stderr();:{MetaItemKind, NestedMetaItemKind, self};
+    let stderr = std::io::stderr();
     let mut stderr = stderr.lock();
     writeln!(stderr, "{} success, {} no mir, {} crate not found, {} failed, \
                         {} C fn, {} ABI, {} unsupported, {} intrinsic",

rustc_tests/src/main.rs

@@ -955,6 +955,8 @@ impl<'a, 'tcx, M: Machine<'tcx>> EvalContext<'a, 'tcx, M> {
                 let variant_def = adt_def.struct_variant();
                 use rustc::ty::layout::Layout::*;
                 match *self.type_layout(ty)? {
+                    UntaggedUnion { ref variants } => 
+                        Ok(TyAndPacked { ty: variant_def.fields[field_index].ty(self.tcx, substs), packed: variants.packed }),
                     Univariant { ref variant, .. } =>
                         Ok(TyAndPacked { ty: variant_def.fields[field_index].ty(self.tcx, substs), packed: variant.packed }),
                     _ => Err(EvalError::Unimplemented(format!("get_field_ty can't handle struct type: {:?}, {:?}", ty, ty.sty))),
@@ -988,8 +990,9 @@ impl<'a, 'tcx, M: Machine<'tcx>> EvalContext<'a, 'tcx, M> {
             StructWrappedNullablePointer { ref nonnull, .. } => {
                 Ok(nonnull.offsets[field_index])
             }
+            UntaggedUnion { .. } => Ok(Size::from_bytes(0)),
             _ => {
-                let msg = format!("can't handle type: {:?}, with layout: {:?}", ty, layout);
+                let msg = format!("get_field_offset: can't handle type: {:?}, with layout: {:?}", ty, layout);
                 Err(EvalError::Unimplemented(msg))
             }
         }
@@ -1006,8 +1009,9 @@ impl<'a, 'tcx, M: Machine<'tcx>> EvalContext<'a, 'tcx, M> {
             Vector { count , .. } |
             Array { count, .. } => Ok(count),
             Scalar { .. } => Ok(0),
+            UntaggedUnion { .. } => Ok(1),
             _ => {
-                let msg = format!("can't handle type: {:?}, with layout: {:?}", ty, layout);
+                let msg = format!("get_field_count: can't handle type: {:?}, with layout: {:?}", ty, layout);
                 Err(EvalError::Unimplemented(msg))
             }
         }

src/librustc_mir/interpret/eval_context.rs

@@ -0,0 +1,21 @@
+// Copyright 2017 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(unsized_tuple_coercion)]
+
+fn main() {
+    let x : &(i32, i32, [i32]) = &(0, 1, [2, 3]);
+    let y : &(i32, i32, [i32]) = &(0, 1, [2, 3, 4]);
+    let mut a = [y, x];
+    a.sort();
+    assert_eq!(a, [x, y]);
+
+    assert_eq!(&format!("{:?}", a), "[(0, 1, [2, 3]), (0, 1, [2, 3, 4])]");
+}