diff --git a/src/base/edition.rs b/src/base/edition.rs
index 31489f95..5b1c16c4 100644
--- a/src/base/edition.rs
+++ b/src/base/edition.rs
@@ -58,7 +58,7 @@ impl<N: Scalar + Zero, R: Dim, C: Dim, S: Storage<N, R, C>> Matrix<N, R, C, S> {
         for j in 0..ncols.value() {
             // FIXME: use unchecked column indexing
             let mut res = res.column_mut(j);
-            let mut src = self.column(j);
+            let src = self.column(j);
 
             for (destination, source) in irows.clone().enumerate() {
                 unsafe {
diff --git a/src/sparse/cs_matrix_solve.rs b/src/sparse/cs_matrix_solve.rs
index 1dfd7843..14ca9f78 100644
--- a/src/sparse/cs_matrix_solve.rs
+++ b/src/sparse/cs_matrix_solve.rs
@@ -78,7 +78,8 @@ impl<N: RealField, D: Dim, S: CsStorage<N, D, D>> CsMatrix<N, D, D, S> {
                 }
 
                 for (i, val) in column {
-                    b[i] -= b[j] * val;
+                    let bj = b[j];
+                    b[i] -= bj * val;
                 }
             }
         }
@@ -119,7 +120,8 @@ impl<N: RealField, D: Dim, S: CsStorage<N, D, D>> CsMatrix<N, D, D, S> {
 
                 if let Some(diag) = diag {
                     for (i, val) in column {
-                        b[j] -= val * b[i];
+                        let bi = b[i];
+                        b[j] -= val * bi;
                     }
 
                     b[j] /= diag;
@@ -178,7 +180,8 @@ impl<N: RealField, D: Dim, S: CsStorage<N, D, D>> CsMatrix<N, D, D, S> {
             }
 
             for (i, val) in column {
-                workspace[i] -= workspace[j] * val;
+                let wj = workspace[j];
+                workspace[i] -= wj * val;
             }
         }
 
diff --git a/tests/geometry/isometry.rs b/tests/geometry/isometry.rs
index cf3a4dfa..ecf29e94 100644
--- a/tests/geometry/isometry.rs
+++ b/tests/geometry/isometry.rs
@@ -1,7 +1,6 @@
 #![cfg(feature = "arbitrary")]
 #![allow(non_snake_case)]
 
-use alga::linear::{ProjectiveTransformation, Transformation};
 use na::{
     Isometry2, Isometry3, Point2, Point3, Rotation2, Rotation3, Translation2, Translation3,
     UnitComplex, UnitQuaternion, Vector2, Vector3,
diff --git a/tests/geometry/similarity.rs b/tests/geometry/similarity.rs
index 475af976..a5736864 100644
--- a/tests/geometry/similarity.rs
+++ b/tests/geometry/similarity.rs
@@ -1,7 +1,6 @@
 #![cfg(feature = "arbitrary")]
 #![allow(non_snake_case)]
 
-use alga::linear::{ProjectiveTransformation, Transformation};
 use na::{Isometry3, Point3, Similarity3, Translation3, UnitQuaternion, Vector3};
 
 quickcheck!(