diff --git a/nbdkit.spec b/nbdkit.spec
index 1b6062d..f4efeee 100644
--- a/nbdkit.spec
+++ b/nbdkit.spec
@@ -44,7 +44,7 @@ ExclusiveArch:  x86_64
 %global verify_tarball_signature 1
 
 # If there are patches which touch autotools files, set this to 1.
-%global patches_touch_autotools %{nil}
+%global patches_touch_autotools 1
 
 # The source directory.
 %global source_directory 1.26-stable