diff --git a/vector-space.cabal b/vector-space.cabal
--- a/vector-space.cabal
+++ b/vector-space.cabal
@@ -1,5 +1,5 @@
 Name:                vector-space
-Version:             0.11
+Version:             0.12
 Cabal-Version:       >= 1.6
 Synopsis:            Vector & affine spaces, linear maps, and derivatives
 Category:            math
@@ -51,6 +51,9 @@
   -- This library relies on type families working as well as in 6.10.
   if impl(ghc < 6.10) {
     buildable: False
+  }
+  if !impl(ghc >= 7.9) {
+    Build-Depends: void >= 0.4
   }
   ghc-options:         -Wall -O2
 --  ghc-prof-options:    -prof -auto-all