diff --git a/3.4.1-fix-windres-s390x.patch b/3.4.1-fix-windres-s390x.patch
new file mode 100644
index 0000000..0a9b3d3
--- /dev/null
+++ b/3.4.1-fix-windres-s390x.patch
@@ -0,0 +1,11 @@
+--- openslide-3.4.1/configure.orig	2020-10-11 20:09:50.894162151 -0400
++++ openslide-3.4.1/configure	2020-10-11 20:10:22.971551105 -0400
+@@ -12521,7 +12521,7 @@
+ CC=$lt_save_CC
+ CFLAGS=$lt_save_CFLAGS
+ 
+- if test x$RC != x; then
++ if test $host_os = mingw32; then
+   WINDOWS_RESOURCES_TRUE=
+   WINDOWS_RESOURCES_FALSE='#'
+ else
diff --git a/openslide.spec b/openslide.spec
index eb3ef2e..fc7df63 100644
--- a/openslide.spec
+++ b/openslide.spec
@@ -6,6 +6,8 @@ Summary:	C library for reading virtual slides
 License:	LGPLv2
 URL:		http://openslide.org/
 Source0:	https://github.com/%{name}/%{name}/releases/download/v%{version}/%{name}-%{version}.tar.xz
+# Based on upstream a3153fa9fb8e37e14941f441a1647532a6ceaa9a
+Patch0:		3.4.1-fix-windres-s390x.patch
 
 BuildRequires:	pkgconfig(glib-2.0)
 BuildRequires:	pkgconfig(cairo)
@@ -49,6 +51,7 @@ with virtual slides.
 
 %prep
 %setup -q
+%patch0 -p1
 
 
 %build
@@ -79,6 +82,9 @@ find $RPM_BUILD_ROOT -name '*.la' -exec rm -f {} ';'
 
 
 %changelog
+* Sun Oct 11 2020 Benjamin Gilbert <bgilbert@backtick.net> - 3.4.1-18
+- Fix build on s390x
+
 * Sat Aug 01 2020 Fedora Release Engineering <releng@fedoraproject.org> - 3.4.1-17
 - Second attempt - Rebuilt for
   https://fedoraproject.org/wiki/Fedora_33_Mass_Rebuild