$OpenBSD: patch-gcc_dbxout_c,v 1.4 2005/05/29 13:26:49 espie Exp $
--- gcc/dbxout.c.orig	Tue May 17 22:11:41 2005
+++ gcc/dbxout.c	Sun May 29 13:55:46 2005
@@ -1011,7 +1011,7 @@ 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);
