Reconcile treatment of &mut with the docs

Author: nikomatsakis

src/librustc/middle/borrowck/check_loans.rs

@@ -657,12 +657,12 @@ fn check_loans_in_fn<'a>(fk: &visit::fn_kind,
             let move_err = this.analyze_move_out_from_cmt(cmt);
             match move_err {
                 MoveOk => {}
-                MoveWhileBorrowed(loan_path, loan_span) => {
+                MoveWhileBorrowed(move_path, loan_path, loan_span) => {
                     this.bccx.span_err(
                         cap_var.span,
                         fmt!("cannot move `%s` into closure \
                               because it is borrowed",
-                             this.bccx.loan_path_to_str(loan_path)));
+                             this.bccx.loan_path_to_str(move_path)));
                     this.bccx.span_note(
                         loan_span,
                         fmt!("borrow of `%s` occurs here",

src/librustc/middle/borrowck/gather_loans/restrictions.rs

@@ -33,7 +33,7 @@ pub fn compute_restrictions(bccx: @BorrowckCtxt,
         cmt_original: cmt
     };
 
-    ctxt.compute(cmt, restr)
+    ctxt.restrict(cmt, restr)
 }
 
 ///////////////////////////////////////////////////////////////////////////
@@ -50,9 +50,9 @@ impl RestrictionsContext {
         self.bccx.tcx
     }
 
-    fn compute(&self,
-               cmt: mc::cmt,
-               restrictions: RestrictionSet) -> RestrictionResult {
+    fn restrict(&self,
+                cmt: mc::cmt,
+                restrictions: RestrictionSet) -> RestrictionResult {
 
         // Check for those cases where we cannot control the aliasing
         // and make sure that we are not being asked to.
@@ -86,7 +86,9 @@ impl RestrictionsContext {
                 // When we borrow the interior of an enum, we have to
                 // ensure the enum itself is not mutated, because that
                 // could cause the type of the memory to change.
-                self.compute(cmt_base, restrictions | RESTR_MUTATE | RESTR_CLAIM)
+                self.restrict(
+                    cmt_base,
+                    restrictions | RESTR_MUTATE | RESTR_CLAIM)
             }
 
             mc::cat_interior(cmt_base, i) => {
@@ -95,7 +97,7 @@ impl RestrictionsContext {
                 // Overwriting the base would not change the type of
                 // the memory, so no additional restrictions are
                 // needed.
-                let result = self.compute(cmt_base, restrictions);
+                let result = self.restrict(cmt_base, restrictions);
                 self.extend(result, cmt.mutbl, LpInterior(i), restrictions)
             }
 
@@ -105,7 +107,7 @@ impl RestrictionsContext {
                 // When we borrow the interior of an owned pointer, we
                 // cannot permit the base to be mutated, because that
                 // would cause the unique pointer to be freed.
-                let result = self.compute(
+                let result = self.restrict(
                     cmt_base,
                     restrictions | RESTR_MUTATE | RESTR_CLAIM);
                 self.extend(result, cmt.mutbl, LpDeref, restrictions)
@@ -180,16 +182,15 @@ impl RestrictionsContext {
                 // mutability, we can only prevent mutation or prevent
                 // freezing if it is not aliased. Therefore, in such
                 // cases we restrict aliasing on `cmt_base`.
-                if restrictions.intersects(RESTR_MUTATE |
-                                           RESTR_CLAIM |
-                                           RESTR_FREEZE) {
+                if restrictions != RESTR_EMPTY {
                     // R-Deref-Mut-Borrowed-1
-                    let result = self.compute(cmt_base, restrictions | RESTR_ALIAS);
+                    let result = self.restrict(
+                        cmt_base,
+                        RESTR_ALIAS | RESTR_MUTATE | RESTR_CLAIM);
                     self.extend(result, cmt.mutbl, LpDeref, restrictions)
                 } else {
                     // R-Deref-Mut-Borrowed-2
-                    let result = self.compute(cmt_base, restrictions);
-                    self.extend(result, cmt.mutbl, LpDeref, restrictions)
+                    Safe
                 }
             }
 
@@ -200,7 +201,7 @@ impl RestrictionsContext {
 
             mc::cat_stack_upvar(cmt_base) |
             mc::cat_discr(cmt_base, _) => {
-                self.compute(cmt_base, restrictions)
+                self.restrict(cmt_base, restrictions)
             }
         }
     }

src/librustc/middle/borrowck/mod.rs

@@ -315,6 +315,7 @@ pub struct Restriction {
     set: RestrictionSet
 }
 
+#[deriving(Eq)]
 pub struct RestrictionSet {
     bits: u32
 }