Fix FTBFS with clang

[taken from NetBSD kdeartwork3 patches]
(cherry picked from commit 23c3263f1b2b48b729f3877e93abcd9788d7893f)

1 files changed, 6 insertions, 2 deletions

diff --git a/tdescreensaver/kdesavers/vec3.h b/tdescreensaver/kdesavers/vec3.h
index 62aeb8ed..879c55f7 100644
--- a/tdescreensaver/kdesavers/vec3.h
+++ b/tdescreensaver/kdesavers/vec3.h
@@ -148,7 +148,9 @@ inline vec3<T>::vec3(const std::slice_array<T>& a)
 template<typename T>
 inline vec3<T> operator+(vec3<T> a, const vec3<T>& b)
 {
-   a += b;   /* valarray<T>::operator+=(const valarray<T>&) */
+   std::valarray<T> &a_ = a;
+   const std::valarray<T> &b_ = b;
+   a_ += b_;   /* valarray<T>::operator+=(const valarray<T>&) */
    return a;
 }
 
@@ -158,7 +160,9 @@ inline vec3<T> operator+(vec3<T> a, const vec3<T>& b)
 template<typename T>
 inline T operator*(vec3<T> a, const vec3<T>& b)
 {
-   a *= b;   /* valarray<T>::operator*=(const T&) */
+   std::valarray<T> &a_ = a;
+   const std::valarray<T> &b_ = b;
+   a_ *= b_;   /* valarray<T>::operator*=(const valarray<T>&) */
    return a.sum();
 }