diff -Naur a/configure.ac b/configure.ac
--- a/configure.ac	2019-09-09 11:46:49.000000000 +0000
+++ b/configure.ac	2020-05-19 04:26:55.216415743 +0000
@@ -67,7 +67,7 @@
     AS_IF([test "x$on_s390" = "xno" -a "x$with_s390" = "xyes"],
            [LIBBLOCKDEV_SOFT_FAILURE([s390 support requested, but not on s390 arch])
             AM_CONDITIONAL(WITH_S390, false)],
-          [test "x$on_s390" == "xyes" -a "x$with_s390" != "xno"],
+          [test "x$on_s390" = "xyes" -a "x$with_s390" != "xno"],
            [AC_SUBST(WITH_S390, 1)
             AM_CONDITIONAL(WITH_S390, true)
            ],
@@ -86,7 +86,7 @@
 AC_SUBST(WITH_PYTHON2, 0)
 if test "x$with_python2" != "xno"; then
     AC_PATH_PROG([python2], [python2], [no])
-    AS_IF([test "x$python2" == "xno"],
+    AS_IF([test "x$python2" = "xno"],
     [if test "x$with_python2" = "xyes"; then
       LIBBLOCKDEV_SOFT_FAILURE([Python2 support requested, but python2 is not available])
       fi],
@@ -102,7 +102,7 @@
 AC_SUBST(WITH_PYTHON3, 0)
 if test "x$with_python3" != "xno"; then
     AC_PATH_PROG([python3], [python3], [no])
-    AS_IF([test "x$python3" == "xno"],
+    AS_IF([test "x$python3" = "xno"],
     [if test "x$with_python3" = "xyes"; then
       LIBBLOCKDEV_SOFT_FAILURE([Python3 support requested, but python3 is not available])
       fi],
@@ -119,7 +119,7 @@
 AC_SUBST(WITH_GTK_DOC, 0)
 if test "x$with_gtk_doc" != "xno"; then
     AC_PATH_PROG([gtkdoc_scan], [gtkdoc-scan], [no])
-    AS_IF([test "x$gtkdoc_scan" == "xno"],
+    AS_IF([test "x$gtkdoc_scan" = "xno"],
     [if test "x$with_gtk_doc" = "xyes"; then
       LIBBLOCKDEV_SOFT_FAILURE([Building documentation with gtk-doc requested, but not available])
       fi],