Fix static_assert for c++14.
diff --git a/unsupported/Eigen/src/AutoDiff/CoherentPadOp.h b/unsupported/Eigen/src/AutoDiff/CoherentPadOp.h
index 0fdd696..7d3a3fb 100644
--- a/unsupported/Eigen/src/AutoDiff/CoherentPadOp.h
+++ b/unsupported/Eigen/src/AutoDiff/CoherentPadOp.h
@@ -51,7 +51,7 @@
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE CoherentPadOp(CoherentPadOp&& other) = default;
 
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE CoherentPadOp(const XprType& xpr, Index size) : xpr_(xpr), size_(size) {
-    static_assert(XprNested_::IsVectorAtCompileTime && "input type must be a vector");
+    static_assert(XprNested_::IsVectorAtCompileTime, "input type must be a vector");
   }
 
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const XprNested_& nestedExpression() const { return xpr_; }