borrowck: classify expressions as assignees, uses or both

- Repurposes `MoveData.assignee_ids` to mean only `=` but not `+=`, so
  that borrowck effectively classifies all expressions into assignees,
  uses or both.
- Removes two `span_err` in liveness analysis, which are now borrowck's
  responsibilities.

Closes #12527.

22 files changed, 56 insertions, 3 deletions

diff --git a/src/test/compile-fail/asm-out-read-uninit.rs b/src/test/compile-fail/asm-out-read-uninit.rs
index b63865921c6..65750eb926b 100644
--- a/src/test/compile-fail/asm-out-read-uninit.rs
+++ b/src/test/compile-fail/asm-out-read-uninit.rs
@@ -19,7 +19,7 @@ fn foo(x: int) { info!("{}", x); }
 pub fn main() {
     let x: int;
     unsafe {
-        asm!("mov $1, $0" : "=r"(x) : "r"(x)); //~ ERROR use of possibly uninitialized value: `x`
+        asm!("mov $1, $0" : "=r"(x) : "r"(x)); //~ ERROR use of possibly uninitialized variable: `x`
     }
     foo(x);
 }
diff --git a/src/test/compile-fail/liveness-and-init.rs b/src/test/compile-fail/borrowck-and-init.rs
index 134390d0b59..134390d0b59 100644
--- a/src/test/compile-fail/liveness-and-init.rs
+++ b/src/test/compile-fail/borrowck-and-init.rs
diff --git a/src/test/compile-fail/liveness-block-unint.rs b/src/test/compile-fail/borrowck-block-unint.rs
index c46b9013a06..fc865e271e3 100644
--- a/src/test/compile-fail/liveness-block-unint.rs
+++ b/src/test/compile-fail/borrowck-block-unint.rs
@@ -11,7 +11,7 @@
 fn force(f: ||) { f(); }
 fn main() {
     let x: int;
-    force(|| {
-        info!("{}", x); //~ ERROR capture of possibly uninitialized variable: `x`
+    force(|| {  //~ ERROR capture of possibly uninitialized variable: `x`
+        info!("{}", x);
     });
 }
diff --git a/src/test/compile-fail/liveness-break-uninit-2.rs b/src/test/compile-fail/borrowck-break-uninit-2.rs
index accb9076974..accb9076974 100644
--- a/src/test/compile-fail/liveness-break-uninit-2.rs
+++ b/src/test/compile-fail/borrowck-break-uninit-2.rs
diff --git a/src/test/compile-fail/liveness-break-uninit.rs b/src/test/compile-fail/borrowck-break-uninit.rs
index d49e79d2c64..d49e79d2c64 100644
--- a/src/test/compile-fail/liveness-break-uninit.rs
+++ b/src/test/compile-fail/borrowck-break-uninit.rs
diff --git a/src/test/compile-fail/liveness-if-no-else.rs b/src/test/compile-fail/borrowck-if-no-else.rs
index 8dc590b47f0..8dc590b47f0 100644
--- a/src/test/compile-fail/liveness-if-no-else.rs
+++ b/src/test/compile-fail/borrowck-if-no-else.rs
diff --git a/src/test/compile-fail/liveness-if-with-else.rs b/src/test/compile-fail/borrowck-if-with-else.rs
index 55fb8222634..55fb8222634 100644
--- a/src/test/compile-fail/liveness-if-with-else.rs
+++ b/src/test/compile-fail/borrowck-if-with-else.rs
diff --git a/src/test/compile-fail/liveness-init-in-called-fn-expr.rs b/src/test/compile-fail/borrowck-init-in-called-fn-expr.rs
index d759a5738bd..d759a5738bd 100644
--- a/src/test/compile-fail/liveness-init-in-called-fn-expr.rs
+++ b/src/test/compile-fail/borrowck-init-in-called-fn-expr.rs
diff --git a/src/test/compile-fail/liveness-init-in-fn-expr.rs b/src/test/compile-fail/borrowck-init-in-fn-expr.rs
index f6bb2f54283..f6bb2f54283 100644
--- a/src/test/compile-fail/liveness-init-in-fn-expr.rs
+++ b/src/test/compile-fail/borrowck-init-in-fn-expr.rs
diff --git a/src/test/compile-fail/liveness-init-in-fru.rs b/src/test/compile-fail/borrowck-init-in-fru.rs
index 97fc2b4d44c..97fc2b4d44c 100644
--- a/src/test/compile-fail/liveness-init-in-fru.rs
+++ b/src/test/compile-fail/borrowck-init-in-fru.rs
diff --git a/src/test/compile-fail/liveness-init-op-equal.rs b/src/test/compile-fail/borrowck-init-op-equal.rs
index cbe805551c2..cbe805551c2 100644
--- a/src/test/compile-fail/liveness-init-op-equal.rs
+++ b/src/test/compile-fail/borrowck-init-op-equal.rs
diff --git a/src/test/compile-fail/liveness-init-plus-equal.rs b/src/test/compile-fail/borrowck-init-plus-equal.rs
index 6e813809f03..6e813809f03 100644
--- a/src/test/compile-fail/liveness-init-plus-equal.rs
+++ b/src/test/compile-fail/borrowck-init-plus-equal.rs
diff --git a/src/test/compile-fail/liveness-or-init.rs b/src/test/compile-fail/borrowck-or-init.rs
index f878afce969..f878afce969 100644
--- a/src/test/compile-fail/liveness-or-init.rs
+++ b/src/test/compile-fail/borrowck-or-init.rs
diff --git a/src/test/compile-fail/liveness-return.rs b/src/test/compile-fail/borrowck-return.rs
index 6558bc57968..6558bc57968 100644
--- a/src/test/compile-fail/liveness-return.rs
+++ b/src/test/compile-fail/borrowck-return.rs
diff --git a/src/test/compile-fail/liveness-uninit-after-item.rs b/src/test/compile-fail/borrowck-uninit-after-item.rs
index a828b1d6b9f..a828b1d6b9f 100644
--- a/src/test/compile-fail/liveness-uninit-after-item.rs
+++ b/src/test/compile-fail/borrowck-uninit-after-item.rs
diff --git a/src/test/compile-fail/borrowck-uninit-in-assignop.rs b/src/test/compile-fail/borrowck-uninit-in-assignop.rs
new file mode 100644
index 00000000000..b5e462e592a
--- /dev/null
+++ b/src/test/compile-fail/borrowck-uninit-in-assignop.rs
@@ -0,0 +1,44 @@
+// Copyright 2012-2014 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.
+
+// Tests that the use of uninitialized variable in assignment operator
+// expression is detected.
+
+pub fn main() {
+    let x: int;
+    x += 1; //~ ERROR use of possibly uninitialized variable: `x`
+
+    let x: int;
+    x -= 1; //~ ERROR use of possibly uninitialized variable: `x`
+
+    let x: int;
+    x *= 1; //~ ERROR use of possibly uninitialized variable: `x`
+
+    let x: int;
+    x /= 1; //~ ERROR use of possibly uninitialized variable: `x`
+
+    let x: int;
+    x %= 1; //~ ERROR use of possibly uninitialized variable: `x`
+
+    let x: int;
+    x ^= 1; //~ ERROR use of possibly uninitialized variable: `x`
+
+    let x: int;
+    x &= 1; //~ ERROR use of possibly uninitialized variable: `x`
+
+    let x: int;
+    x |= 1; //~ ERROR use of possibly uninitialized variable: `x`
+
+    let x: int;
+    x <<= 1;    //~ ERROR use of possibly uninitialized variable: `x`
+
+    let x: int;
+    x >>= 1;    //~ ERROR use of possibly uninitialized variable: `x`
+}
diff --git a/src/test/compile-fail/liveness-uninit.rs b/src/test/compile-fail/borrowck-uninit.rs
index a6ce736c89b..a6ce736c89b 100644
--- a/src/test/compile-fail/liveness-uninit.rs
+++ b/src/test/compile-fail/borrowck-uninit.rs
diff --git a/src/test/compile-fail/liveness-use-in-index-lvalue.rs b/src/test/compile-fail/borrowck-use-in-index-lvalue.rs
index 7ec0607fc97..3ced9859240 100644
--- a/src/test/compile-fail/liveness-use-in-index-lvalue.rs
+++ b/src/test/compile-fail/borrowck-use-in-index-lvalue.rs
@@ -11,6 +11,10 @@
 fn test() {
     let w: ~[int];
     w[5] = 0; //~ ERROR use of possibly uninitialized variable: `w`
+              //~^ ERROR cannot assign to immutable vec content `w[..]`
+
+    let mut w: ~[int];
+    w[5] = 0; //~ ERROR use of possibly uninitialized variable: `w`
 }
 
 fn main() { test(); }
diff --git a/src/test/compile-fail/liveness-while-break.rs b/src/test/compile-fail/borrowck-while-break.rs
index e5d4b6ef48c..e5d4b6ef48c 100644
--- a/src/test/compile-fail/liveness-while-break.rs
+++ b/src/test/compile-fail/borrowck-while-break.rs
diff --git a/src/test/compile-fail/liveness-while-cond.rs b/src/test/compile-fail/borrowck-while-cond.rs
index 27d42d666ea..27d42d666ea 100644
--- a/src/test/compile-fail/liveness-while-cond.rs
+++ b/src/test/compile-fail/borrowck-while-cond.rs
diff --git a/src/test/compile-fail/liveness-while.rs b/src/test/compile-fail/borrowck-while.rs
index b904fd53d72..b904fd53d72 100644
--- a/src/test/compile-fail/liveness-while.rs
+++ b/src/test/compile-fail/borrowck-while.rs
diff --git a/src/test/compile-fail/liveness-unused.rs b/src/test/compile-fail/liveness-unused.rs
index 83c911d916e..33fc094abbe 100644
--- a/src/test/compile-fail/liveness-unused.rs
+++ b/src/test/compile-fail/liveness-unused.rs
@@ -23,6 +23,11 @@ fn f1b(x: &mut int) {
 #[allow(unused_variable)]
 fn f1c(x: int) {}
 
+fn f1d() {
+    let x: int;
+    //~^ ERROR unused variable: `x`
+}
+
 fn f2() {
     let x = 3;
     //~^ ERROR unused variable: `x`