Initial work on targets discovery with global var

libraries/library_a/CMakeLists.txt

@@ -0,0 +1,4 @@
+cmake_minimum_required(VERSION 3.10)
+project(library_a LANGUAGES C)
+
+add_library(${PROJECT_NAME}-lib OBJECT library_a.c)

libraries/library_a/library_a.c

@@ -0,0 +1,6 @@
+#include <stdio.h>
+int library_a(void)
+{
+	printf("%s\n", __func__);
+	return 0;
+}