--- clients/lcdproc/iface.c.orig	2020-09-28 23:25:01.655900000 +0200

+++ clients/lcdproc/iface.c	2020-09-28 23:25:27.294816000 +0200

@@ -37,6 +37,7 @@

 static char unit_label[10] = "B";	/* default unit label is Bytes */

 static int transfer_screen = 0;	/* by default, transfer screen is not shown */

+IfaceInfo iface[MAX_INTERFACES]; /* interface info */

 /** Reads and parses configuration file.

  * \return  0 on success, -1 on error

--- clients/lcdproc/iface.h.orig	2020-09-28 23:24:28.536083000 +0200

+++ clients/lcdproc/iface.h	2020-09-28 23:24:52.494772000 +0200

@@ -18,7 +18,7 @@

 /** max number of interfaces in multi-interface mode */

 #define MAX_INTERFACES 3

-IfaceInfo iface[MAX_INTERFACES];	/* interface info */

+extern IfaceInfo iface[MAX_INTERFACES];	/* interface info */

 /** Update screen content */

 int iface_screen(int rep, int display, int *flags_ptr);