Fix compilation with gcc

Eigen/src/Core/SpecialFunctions.h

diff --git a/Eigen/src/Core/SpecialFunctions.h b/Eigen/src/Core/SpecialFunctions.h
index 21583e6..9f89e18 100644
--- a/Eigen/src/Core/SpecialFunctions.h
+++ b/Eigen/src/Core/SpecialFunctions.h
@@ -81,7 +81,7 @@
 struct polevl {
   EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE
   static Scalar run(const Scalar x, const Scalar coef[]) {
-    EIGEN_STATIC_ASSERT(N > 0, YOU_MADE_A_PROGRAMMING_MISTAKE);
+    EIGEN_STATIC_ASSERT((N > 0), YOU_MADE_A_PROGRAMMING_MISTAKE);
 
     return polevl<Scalar, N - 1>::run(x, coef) * x + coef[N];
   }