diff --git a/include/boost/math/special_functions/gamma.hpp b/include/boost/math/special_functions/gamma.hpp
index c94024614..320a4141b 100644
--- a/include/boost/math/special_functions/gamma.hpp
+++ b/include/boost/math/special_functions/gamma.hpp
@@ -221,7 +221,7 @@ BOOST_MATH_GPU_ENABLED BOOST_MATH_FORCEINLINE T gamma_imp(T z, const Policy& pol
          }
 #endif
          BOOST_MATH_INSTRUMENT_VARIABLE(result);
-         BOOST_IF_CONSTEXPR(!std::numeric_limits<T>::is_specialized || (std::numeric_limits<T>::digits > 64))
+         BOOST_MATH_IF_CONSTEXPR(!std::numeric_limits<T>::is_specialized || (std::numeric_limits<T>::digits > 64))
          {
             if ((fabs(result) < 1) && (tools::max_value<T>() * fabs(result) < boost::math::constants::pi<T>()))
             {