diff --git a/util/ceg/ce_back/as_back/.distr b/util/ceg/ce_back/as_back/.distr
index c98496d8e..483ef9df4 100644
--- a/util/ceg/ce_back/as_back/.distr
+++ b/util/ceg/ce_back/as_back/.distr
@@ -6,7 +6,6 @@ bss.c
 con1.c
 con2.c
 con4.c
-const.h
 do_close.c
 do_open.c
 end_back.c
diff --git a/util/ceg/ce_back/as_back/back.h b/util/ceg/ce_back/as_back/back.h
index 1de8f060d..922799e04 100644
--- a/util/ceg/ce_back/as_back/back.h
+++ b/util/ceg/ce_back/as_back/back.h
@@ -1,12 +1,51 @@
 #include <em.h>
 #include <system.h>
 
-#define codefile	_codefile
-#define cur_seg		_cur_seg
-#define saved		_saved
-#define labeltje	_labeltje
-#define name		_name
-#define output_back	_output_back
+#define codefile	B_codefile
+#define cur_seg		B_cur_seg
+#define saved		B_saved
+#define labeltje	B_labeltje
+#define name		B_name
+#define output_back	B_output_back
+
+/* Macros to change interface names */
+
+#define common		B_common
+#define con1		B_con1
+#define con2		B_con2
+#define con4		B_con4
+#define rom1		B_rom1
+#define rom2		B_rom2
+#define rom4		B_rom4
+#define text1		B_txt1
+#define text2		B_txt2
+#define text4		B_txt4
+#define close_back	B_close_back
+#define open_back	B_open_back
+#define end_back	B_end_back
+#define init_back	B_init_back
+#define extnd_pro	B_ex_pro
+#define extnd_start	B_ex_start
+#define extnd_name	B_ex_name
+#define extnd_dnam	B_ex_dnam
+#define extnd_dlb	B_ex_dlb
+#define extnd_ilb	B_ex_ilb
+#define extnd_hol	B_ex_hol
+#define extnd_part	B_ex_part
+#define extnd_cont	B_ex_cont
+#define gen1		B_gen1
+#define gen2		B_gen2
+#define gen4		B_gen4
+#define save_label	B_save_label
+#define dump_label	B_dump_label
+#define align_word	B_align_word
+#define reloc1		B_rlc1
+#define reloc2		B_rlc2
+#define reloc4		B_rlc4
+#define set_global_visible	B_stglobvis
+#define set_local_visible	B_stlocvis
+#define symbol_definition	B_symdef
+#define switchseg		B_switchseg
 
 extern File *codefile;
 
diff --git a/util/ceg/ce_back/as_back/bottom.c b/util/ceg/ce_back/as_back/bottom.c
index 8b7b54671..e47c39316 100644
--- a/util/ceg/ce_back/as_back/bottom.c
+++ b/util/ceg/ce_back/as_back/bottom.c
@@ -1,10 +1,8 @@
-#include "mach.h"
-#include "const.h"
-#include "back.h"
+#include "header.h"
 
 /* This file contains low-level routines for generating assembly code. */
 
-int cur_seg = -1, saved = FALSE;
+int cur_seg = -1, saved = 0;
 char name[256], labeltje[256];
 
 File *codefile;
@@ -27,7 +25,7 @@ save_label( l)
 char *l;
 {
 	sprint( labeltje, "%s", l);
-	saved = TRUE;
+	saved = 1;
 }
 
 
@@ -37,7 +35,7 @@ dump_label()
 		align_word();
 		symbol_definition( labeltje);
 	}
-	saved = FALSE;
+	saved = 0;
 }
 
 
@@ -76,7 +74,7 @@ char *s;
 char *extnd_dlb( g)
 arith g;
 {
-	sprint( name, DLB_FMT, (arith)g);
+	sprint( name, DLB_FMT, (long)g);
         return( name);
 }
 
@@ -84,7 +82,7 @@ arith g;
 char *extnd_ilb( l, prcno)
 arith l;
 {
-	sprint( name, ILB_FMT, prcno, (arith) l);
+	sprint( name, ILB_FMT, prcno, (long) l);
         return( name);
 }
 
@@ -100,7 +98,7 @@ int hol;
 char *extnd_part( d)
 int d;
 {
-	sprint( name, "part%x", (arith) d);
+	sprint( name, "part%x", d);
 	return( name);
 }
 
@@ -108,6 +106,6 @@ int d;
 char *extnd_cont( d)
 int d;
 {
-	sprint( name, "cont%x", (arith) d);
+	sprint( name, "cont%x", d);
 	return( name);
 }
diff --git a/util/ceg/ce_back/as_back/do_open.c b/util/ceg/ce_back/as_back/do_open.c
index 973d53fde..e2dd16dda 100644
--- a/util/ceg/ce_back/as_back/do_open.c
+++ b/util/ceg/ce_back/as_back/do_open.c
@@ -3,8 +3,8 @@
 open_back( filename)
 char *filename;
 {
-	if ( filename == (char *) '\0')
-		return( FALSE);
+	if ( filename == (char *) 0)
+		return( 0);
 	else
 		return( sys_open( filename, OP_WRITE, &codefile));
 }
diff --git a/util/ceg/ce_back/as_back/header.h b/util/ceg/ce_back/as_back/header.h
index 9f9103efa..120123825 100644
--- a/util/ceg/ce_back/as_back/header.h
+++ b/util/ceg/ce_back/as_back/header.h
@@ -1,5 +1,4 @@
 #include "mach.h"
-#include "const.h"
 #include "back.h"
 
 extern int cur_seg;