diff --git a/libxcrypt.spec b/libxcrypt.spec
index c0ff2cf..bd1b5ac 100644
--- a/libxcrypt.spec
+++ b/libxcrypt.spec
@@ -20,11 +20,13 @@
 %endif
 
 # Run memcheck?
+%ifarch %{valgrind_arches}
 # Valgrind does not work well on %%{power64} arches.
-%ifnarch %{power64}
-%bcond_without memcheck
-%else
+%ifarch %{power64}
 %bcond_with    memcheck
+%else
+%bcond_without memcheck
+%endif
 %endif