diff --git a/var/spack/repos/builtin/packages/lua/package.py b/var/spack/repos/builtin/packages/lua/package.py
index 420e3b041a4..910d8b252f1 100644
--- a/var/spack/repos/builtin/packages/lua/package.py
+++ b/var/spack/repos/builtin/packages/lua/package.py
@@ -139,7 +139,7 @@ def setup_dependent_run_environment(self, env, dependent_spec):
 
         if dependent_spec.package.extends(self.spec):
             env.prepend_path('LUA_PATH', ';'.join(lua_patterns), separator=';')
-            if '+shared' in spec:
+            if '+shared' in self.spec:
                 env.prepend_path('LUA_CPATH', ';'.join(lua_cpatterns),
                                  separator=';')