diff --git a/byaccj.changes b/byaccj.changes
index e9679cd..7907d1f 100644
--- a/byaccj.changes
+++ b/byaccj.changes
@@ -1,3 +1,9 @@
+-------------------------------------------------------------------
+Tue Jul 27 13:20:50 UTC 2021 - Fridrich Strba <fstrba@suse.com>
+
+- Define %%make_build for systems that don't have it defined in
+  rpm macros
+
 -------------------------------------------------------------------
 Wed Feb  3 18:57:06 UTC 2021 - Pedro Monreal <pmonreal@suse.com>
 
diff --git a/byaccj.spec b/byaccj.spec
index 75f2b93..b7eaf30 100644
--- a/byaccj.spec
+++ b/byaccj.spec
@@ -16,6 +16,7 @@
 #
 
 
+%{!?make_build:%global make_build make %{?_smp_mflags}}
 %define jpp_release 3
 Name:           byaccj
 Version:        1.15