diff -r -w -u0 willuslib/bmpmupdf.c willuslib/bmpmupdf.c
--- willuslib/bmpmupdf.c    2018-11-20 21:13:12.000000000 +0100
+++ willuslib/bmpmupdf.c    2019-07-27 20:12:37.386555334 +0200
@@ -28 +28,3 @@
-void pdf_install_load_system_font_funcs(fz_context *ctx);
+void pdf_install_load_system_font_funcs(fz_context *ctx)
+{
+}