diff --git a/macros.fedora-misc b/macros.fedora-misc
index a73b7c5..83e455a 100644
--- a/macros.fedora-misc
+++ b/macros.fedora-misc
@@ -12,9 +12,9 @@
 # Arguments passed to the macro without flags will be interpreted as inclusion
 # globs.
 %listfiles(i:x:) %{expand:
-%if "%{?-i*}%{expand:?listfiles_include}%*" != ""
+%if %{lua: print(string.len(rpm.expand("%{?-i*}%{?listfiles_include}%*")))}
   listfiles_include=$(realpath -e --relative-base=. %{?-i*} %{?listfiles_include} %* | sort -u)
-  %if "%{?-x*}%{expand:?listfiles_exclude}" != ""
+  %if  %{lua: print(string.len(rpm.expand("%{?-x*}%{?listfiles_exclude}")))}
     while IFS= read -r finc ; do
       realpath -qe --relative-base=. %{?-x*} %{?listfiles_exclude} \\
         | sort -u | grep -q "${finc}" || echo "${finc}"
diff --git a/redhat-rpm-config.spec b/redhat-rpm-config.spec
index 13d4662..9acd12b 100644
--- a/redhat-rpm-config.spec
+++ b/redhat-rpm-config.spec
@@ -202,6 +202,7 @@ install -p -m 644 -t %{buildroot}%{_rpmluadir}/fedora/srpm forge.lua
 %{_rpmconfigdir}/macros.d/macros.kmp
 
 %changelog
+- listfiles: make it robust against all kinds of “interesting” inputs
 - wordwrap: make list indenting smarter, to produce something with enough
   structure that it can be converted into AppStream metadata