diff --git a/src/Makefile.housekeeping b/src/Makefile.housekeeping
index 70ec50c5..0a80d2ac 100644
--- a/src/Makefile.housekeeping
+++ b/src/Makefile.housekeeping
@@ -734,8 +734,8 @@ $(DBGCOL_LIST) : $(MAKEDEPS)
 VERYCLEANUP += $(DBGCOL_LIST)
 
 DBGCOL_COLOURS := $(subst -, ,$(DBGCOL))
-DBGCOL_MIN := $(word 1,$(DBGCOL_COLOURS))
-DBGCOL_MAX := $(word 2,$(DBGCOL_COLOURS))
+DBGCOL_MIN := $(firstword $(DBGCOL_COLOURS))
+DBGCOL_MAX := $(lastword $(DBGCOL_COLOURS))
 
 debug_DEPS += $(DBGCOL_LIST)
 
diff --git a/src/core/debug.c b/src/core/debug.c
index def5d8b0..9b2a823f 100644
--- a/src/core/debug.c
+++ b/src/core/debug.c
@@ -194,8 +194,12 @@ static int dbg_autocolour ( unsigned long stream ) {
  * @v stream		Message stream ID
  */
 void dbg_autocolourise ( unsigned long stream ) {
-	dbg_printf ( "\033[%dm",
-		     ( stream ? ( DBGCOL_MIN + dbg_autocolour ( stream ) ) :0));
+
+	if ( DBGCOL_MIN ) {
+		dbg_printf ( "\033[%dm",
+			     ( stream ?
+			       ( DBGCOL_MIN + dbg_autocolour ( stream ) ) : 0));
+	}
 }
 
 /**
@@ -203,5 +207,7 @@ void dbg_autocolourise ( unsigned long stream ) {
  *
  */
 void dbg_decolourise ( void ) {
-	dbg_printf ( "\033[0m" );
+
+	if ( DBGCOL_MIN )
+		dbg_printf ( "\033[0m" );
 }