--- files/patch-glib-demo-CMakeLists.txt	(nonexistent)
+++ files/patch-glib-demo-CMakeLists.txt	(working copy)
@@ -0,0 +1,16 @@ 
+Fix this error:
+/usr/bin/ld: cannot find -lgtk-3
+see https://stackoverflow.com/questions/29191855/what-is-the-proper-way-to-use-pkg-config-from-cmake
+need to add -L paths as well as -lgtk-3; try to leverage pkg-config
+ Note: earlier attempt to change GTK3_LIBRARIES to PkgConfig::GTK3 didn't add -L paths to link.txt
+
+--- glib/demo/CMakeLists.txt.orig	2019-12-28 12:18:51 UTC
++++ glib/demo/CMakeLists.txt
+@@ -27,4 +27,6 @@
+   taggedstruct.c
+ )
+ poppler_add_test(poppler-glib-demo BUILD_GTK_TESTS ${poppler_glib_demo_SRCS})
+-target_link_libraries(poppler-glib-demo ${CAIRO_LIBRARIES} poppler-glib ${GTK3_LIBRARIES})
++find_package(PkgConfig REQUIRED)
++pkg_check_modules(GTK3 REQUIRED IMPORTED_TARGET gtk+-3.0)
++target_link_libraries(poppler-glib-demo ${CAIRO_LIBRARIES} poppler-glib PkgConfig::GTK3)