diff --git a/src/librustc/middle/liveness.rs b/src/librustc/middle/liveness.rs
index e725f8629fb..90bcdb54e19 100644
--- a/src/librustc/middle/liveness.rs
+++ b/src/librustc/middle/liveness.rs
@@ -640,8 +640,8 @@ struct Liveness {
     tcx: ty::ctxt,
     ir: @IrMaps,
     s: Specials,
-    mut successors: ~[LiveNode],
-    mut users: ~[users],
+    successors: ~[mut LiveNode],
+    users: ~[mut users],
     // The list of node IDs for the nested loop scopes
     // we're in.
     loop_scope: DVec<node_id>,
diff --git a/src/librustc/middle/trans/cabi_x86_64.rs b/src/librustc/middle/trans/cabi_x86_64.rs
index 699b82b7dd4..e4a70241d1a 100644
--- a/src/librustc/middle/trans/cabi_x86_64.rs
+++ b/src/librustc/middle/trans/cabi_x86_64.rs
@@ -127,13 +127,13 @@ fn classify_ty(ty: TypeRef) -> ~[x86_64_reg_class] {
         }
     }
 
-    fn all_mem(cls: &mut [x86_64_reg_class]) {
+    fn all_mem(cls: &[mut x86_64_reg_class]) {
         for uint::range(0, cls.len()) |i| {
             cls[i] = memory_class;
         }
     }
 
-    fn unify(cls: &mut [x86_64_reg_class],
+    fn unify(cls: &[mut x86_64_reg_class],
              i: uint,
              newv: x86_64_reg_class) {
         if cls[i] == newv {
@@ -159,7 +159,7 @@ fn classify_ty(ty: TypeRef) -> ~[x86_64_reg_class] {
     }
 
     fn classify_struct(tys: &[TypeRef],
-                       cls: &mut [x86_64_reg_class], i: uint,
+                       cls: &[mut x86_64_reg_class], i: uint,
                        off: uint) {
         let mut field_off = off;
         for vec::each(tys) |ty| {
@@ -170,7 +170,7 @@ fn classify_ty(ty: TypeRef) -> ~[x86_64_reg_class] {
     }
 
     fn classify(ty: TypeRef,
-                cls: &mut [x86_64_reg_class], ix: uint,
+                cls: &[mut x86_64_reg_class], ix: uint,
                 off: uint) {
         unsafe {
             let t_align = ty_align(ty);
@@ -220,7 +220,7 @@ fn classify_ty(ty: TypeRef) -> ~[x86_64_reg_class] {
         }
     }
 
-    fn fixup(ty: TypeRef, cls: &mut [x86_64_reg_class]) {
+    fn fixup(ty: TypeRef, cls: &[mut x86_64_reg_class]) {
         unsafe {
             let mut i = 0u;
             let llty = llvm::LLVMGetTypeKind(ty) as int;
diff --git a/src/librustc/middle/trans/type_use.rs b/src/librustc/middle/trans/type_use.rs
index c11d4f5ebc0..c19db4a75b9 100644
--- a/src/librustc/middle/trans/type_use.rs
+++ b/src/librustc/middle/trans/type_use.rs
@@ -49,7 +49,7 @@ pub const use_repr: uint = 1u;   /* Dependency on size/alignment/mode and
                                     take/drop glue */
 pub const use_tydesc: uint = 2u; /* Takes the tydesc, or compares */
 
-pub type ctx = {ccx: @crate_ctxt, mut uses: ~[type_uses]};
+pub type ctx = {ccx: @crate_ctxt, uses: ~[mut type_uses]};
 
 pub fn type_uses_for(ccx: @crate_ctxt, fn_id: def_id, n_tps: uint)
     -> ~[type_uses] {
diff --git a/src/librustc/middle/typeck/check/method.rs b/src/librustc/middle/typeck/check/method.rs
index 34798387d73..44dd65f238b 100644
--- a/src/librustc/middle/typeck/check/method.rs
+++ b/src/librustc/middle/typeck/check/method.rs
@@ -778,7 +778,7 @@ pub impl LookupContext {
         /*!
          *
          * In the event that we are invoking a method with a receiver
-         * of a linear borrowed type like `&mut T` or `&mut [T]`,
+         * of a linear borrowed type like `&mut T` or `&[mut T]`,
          * we will "reborrow" the receiver implicitly.  For example, if
          * you have a call `r.inc()` and where `r` has type `&mut T`,
          * then we treat that like `(&mut *r).inc()`.  This avoids
diff --git a/src/librustc/middle/typeck/infer/region_inference.rs b/src/librustc/middle/typeck/infer/region_inference.rs
index d928ad264fd..5d602ab88bb 100644
--- a/src/librustc/middle/typeck/infer/region_inference.rs
+++ b/src/librustc/middle/typeck/infer/region_inference.rs
@@ -1191,11 +1191,11 @@ struct GraphNode {
     span: span,
     mut classification: Classification,
     mut value: GraphNodeValue,
-    head_edge: [uint * 2],
+    head_edge: [mut uint * 2], // FIXME(#3226)--should not need mut
 }
 
 struct GraphEdge {
-    next_edge: [uint * 2],
+    next_edge: [mut uint * 2], // FIXME(#3226)--should not need mut
     constraint: Constraint,
     span: span,
 }
@@ -1237,7 +1237,7 @@ impl RegionVarBindings {
                 classification: Contracting,
                 span: self.var_spans[var_idx],
                 value: NoValue,
-                head_edge: [uint::max_value, uint::max_value]
+                head_edge: [mut uint::max_value, uint::max_value]
             }
         });
 
@@ -1245,7 +1245,7 @@ impl RegionVarBindings {
         let mut edges = vec::with_capacity(num_edges);
         for self.constraints.each_ref |constraint, span| {
             edges.push(GraphEdge {
-                next_edge: [uint::max_value, uint::max_value],
+                next_edge: [mut uint::max_value, uint::max_value],
                 constraint: *constraint,
                 span: *span
             });