$OpenBSD: patch-gcc_dbxout_c,v 1.5 2006/03/05 22:11:15 espie Exp $
--- gcc/dbxout.c.orig	Thu Oct  6 02:47:21 2005
+++ gcc/dbxout.c	Sat Mar  4 14:34:46 2006
@@ -1012,7 +1012,7 @@ dbxout_init (const char *input_file_name
 	  if (cwd[0] == '\0')
 	    cwd = "/";
 	  else if (!IS_DIR_SEPARATOR (cwd[strlen (cwd) - 1]))
-	    cwd = concat (cwd, "/", NULL);
+	    cwd = concat (cwd, "/", (void *)0);
 	}
 #ifdef DBX_OUTPUT_MAIN_SOURCE_DIRECTORY
       DBX_OUTPUT_MAIN_SOURCE_DIRECTORY (asm_out_file, cwd);
