diff --git a/tool/run/run b/tool/run/run
index 53678caa6..f0278147a 100755
--- a/tool/run/run
+++ b/tool/run/run
@@ -812,7 +812,9 @@ proc build_core_image { modules } {
 	copy_genode_binaries_to_run_dir $modules
 
 	# create core binary without modules for debugging
-	build_core debug/$core_obj {} [run_dir].core [core_link_address]
+	if {[file exists debug/$core_obj]} {
+		build_core debug/$core_obj {} [run_dir].core [core_link_address]
+	}
 
 	# determine modules to be incorporated into the core image
 	set modules [glob -nocomplain -tails -directory [run_dir]/genode/ *]