Fix two more write guard failures

Author: nikomatsakis

src/librustc/middle/resolve.rs

@@ -4825,10 +4825,12 @@ pub impl Resolver {
 
             expr_loop(_, Some(label)) => {
                 do self.with_label_rib {
-                    let this = &mut *self;
-                    let def_like = dl_def(def_label(expr.id));
-                    let rib = this.label_ribs[this.label_ribs.len() - 1];
-                    rib.bindings.insert(label, def_like);
+                    {
+                        let this = &mut *self;
+                        let def_like = dl_def(def_label(expr.id));
+                        let rib = this.label_ribs[this.label_ribs.len() - 1];
+                        rib.bindings.insert(label, def_like);
+                    }
 
                     visit_expr(expr, (), visitor);
                 }

src/libsyntax/ext/pipes/liveness.rs

@@ -42,7 +42,7 @@ use ext::pipes::proto::{protocol_};
 
 use std::bitv::Bitv;
 
-pub fn analyze(proto: &mut protocol_, _cx: @ext_ctxt) {
+pub fn analyze(proto: @mut protocol_, _cx: @ext_ctxt) {
     debug!("initializing colive analysis");
     let num_states = proto.num_states();
     let mut colive = do (copy proto.states).map_to_vec |state| {

src/test/run-fail/borrowck-wg-imm-then-mut.rs

@@ -0,0 +1,19 @@
+// error-pattern:borrowed
+
+// Test that if you imm borrow then mut borrow it fails.
+
+fn add1(a:@mut int)
+{
+    add2(a); // already frozen
+}
+
+fn add2(_:&mut int)
+{
+}
+
+pub fn main()
+{
+    let a = @mut 3;
+    let b = &*a; // freezes a
+    add1(a);
+}

src/test/run-fail/borrowck-wg-mut-then-imm.rs

@@ -0,0 +1,19 @@
+// error-pattern:borrowed
+
+// Test that if you mut borrow then imm borrow it fails.
+
+fn add1(a:@mut int)
+{
+    add2(a); // already frozen
+}
+
+fn add2(_:&int)
+{
+}
+
+pub fn main()
+{
+    let a = @mut 3;
+    let b = &mut *a; // freezes a
+    add1(a);
+}