diff --git a/zlib.spec b/zlib.spec
index 709e865..f55b28a 100644
--- a/zlib.spec
+++ b/zlib.spec
@@ -69,14 +69,9 @@ iconv -f iso-8859-2 -t utf-8 < ChangeLog > ChangeLog.tmp
 mv ChangeLog.tmp ChangeLog
 
 %build
-%if 0%{?rhel} >= 7
-    %ifarch ppc64
-        export CFLAGS="$RPM_OPT_FLAGS -O3"
-    %else
-        export CFLAGS="$RPM_OPT_FLAGS"
-    %endif
-%else
 export CFLAGS="$RPM_OPT_FLAGS"
+%ifarch ppc64
+CFLAGS+=" -O3"
 %endif
 export LDFLAGS="$LDFLAGS -Wl,-z,relro -Wl,-z,now"
 ./configure --libdir=%{_libdir} --includedir=%{_includedir} --prefix=%{_prefix}
@@ -140,6 +135,7 @@ rm -f $RPM_BUILD_ROOT%{_libdir}/*.la
 %changelog
 * Thu Feb 09 2017 Pavel Raiskup <praiskup@redhat.com> - 1.2.11-2
 - fix s390(x) optimizing patch (FTBFS on s390(x))
+- simplify ppc64 hack with -O3
 
 * Mon Jan 30 2017 Pavel Raiskup <praiskup@redhat.com> - 1.2.11-1
 - latest upstream release (rhbz#1409372)