diff --git a/src/functions.c b/src/functions.c
index 9a43981..112776e 100644
--- a/src/functions.c
+++ b/src/functions.c
@@ -38,6 +38,8 @@ typedef struct {
     void *address;
 } ProcMap;
 
+int _ogx_functions_c = 0; /* referenced by gc_gl.c, see the comment in there */
+
 #define PROC(name) { #name, name }
 static const ProcMap s_proc_map[] = {
     //PROC(glAccum),
diff --git a/src/gc_gl.c b/src/gc_gl.c
index 458ef53..dfa4006 100644
--- a/src/gc_gl.c
+++ b/src/gc_gl.c
@@ -79,6 +79,13 @@ typedef struct
 char _ogx_log_level = 0;
 static GXTexObj s_zbuffer_texture;
 static uint8_t s_zbuffer_texels[2 * 32] ATTRIBUTE_ALIGN(32);
+/* Force the inclusion of functions.c's TU in the build when GL functions are
+ * used. In this way, if a client library (such as SDL) defines weak symbols
+ * for the opengx functions it uses, a client application which actually uses
+ * opengx will link and use its real implementation; at the same time, a client
+ * which does not use OpenGL is not forced to link with opengx. */
+extern int _ogx_functions_c;
+void *_ogx_force_proctable = &_ogx_functions_c;
 
 static void draw_arrays_general(DrawMode gxmode, int first, int count, int ne,
                                 int color_provide, int texen);