$NetBSD: patch-ba,v 1.2 2017/06/08 14:06:38 joerg Exp $

Avoid missing prototypes.
Check buffer for the error value, pointers are not signed.

--- Xlib/XlibImage.cc.orig	1997-09-09 13:24:11.000000000 +0000
+++ Xlib/XlibImage.cc
@@ -2,6 +2,7 @@
 #include <X11/Xutil.h>
 #include <sys/ipc.h>
 #include <sys/shm.h>
+#include <string.h>
 #include "Utils.hh"
 
 static bool DontUseShm = FALSE;
@@ -173,7 +174,7 @@ XSHMBuffer::XSHMBuffer(XDrawable* mainw)
 	 "can't create shared memory ID");
   buffer = (Pixel_t *) shmat(shminfo.shmid, 0, 0);
   shminfo.shmaddr = (char *) buffer;
-  if (buffer < 0) {
+  if (buffer == (void *)-1) {
     shmctl(shminfo.shmid, IPC_RMID, 0);
     Die("can't map shared memory");
   }