From NetBSD:
Force proper LDFLAGS for MODULE, as cmake doesn't set rpath for these
Index: gerbview/CMakeLists.txt
--- gerbview/CMakeLists.txt.orig
+++ gerbview/CMakeLists.txt
@@ -178,6 +178,9 @@ target_link_options( gerbview_kiface PRIVATE
 # if building gerbview, then also build gerbview_kiface if out of date.
 add_dependencies( gerbview gerbview_kiface )
 
+set_property(TARGET gerbview_kiface APPEND_STRING
+   PROPERTY LINK_FLAGS " $ENV{LDFLAGS}")
+
 # these 2 binaries are a matched set, keep them together
 if( APPLE )
     set_target_properties( gerbview PROPERTIES
