diff --git a/mach/6500/cg/mach.h b/mach/6500/cg/mach.h
index 3bb921b76..792996a66 100644
--- a/mach/6500/cg/mach.h
+++ b/mach/6500/cg/mach.h
@@ -10,7 +10,7 @@
 #define newilb(x)       fprintf(codefile,"%s:\n",x)
 #define newdlb(x)       fprintf(codefile,"%s:\n",x)
 #define dlbdlb(x,y)     fprintf(codefile,"%s = %s\n",x,y)
-#define newlbss(l,x)    fprintf(codefile,"%s: .space\t%d\n",l,x);
+#define newlbss(l,x)    fprintf(codefile,".comm %s,%u\n",l,x);
 
 #define cst_fmt         "%d"
 #define off_fmt         "%d"
diff --git a/mach/i80/ncg/mach.h b/mach/i80/ncg/mach.h
index 82927cfe0..9c24fc7ed 100644
--- a/mach/i80/ncg/mach.h
+++ b/mach/i80/ncg/mach.h
@@ -9,7 +9,7 @@
 #define newilb(x)       fprintf(codefile,"%s:\n",x)
 #define newdlb(x)       fprintf(codefile,"%s:\n",x)
 #define dlbdlb(x,y)     fprintf(codefile,"%s = %s\n",x,y)
-#define newlbss(l,x)       fprintf(codefile,"%s:.space\t%d\n",l,x);
+#define newlbss(l,x)       fprintf(codefile,".comm %s,%u\n",l,x);
 
 #define cst_fmt         "%d"
 #define off_fmt         "%d"
diff --git a/mach/m68k2/cg/mach.h b/mach/m68k2/cg/mach.h
index a16e5ec22..61f4a6528 100644
--- a/mach/m68k2/cg/mach.h
+++ b/mach/m68k2/cg/mach.h
@@ -9,7 +9,7 @@
 #define newilb(x)	fprintf(codefile,"%s:\n",x)
 #define newdlb(x)	fprintf(codefile,"%s:\n",x)
 #define	dlbdlb(x,y)	fprintf(codefile,"%s = %s\n",x,y)
-#define newlbss(l,x)	fprintf(codefile,"%s:.space\t%ld\n",l,x);
+#define newlbss(l,x)	fprintf(codefile,".comm %s,%ld\n",l,x);
 
 #define	pop_fmt		"(sp)+"
 #define cst_fmt		"%ld"
diff --git a/mach/pdp/cg/mach.h b/mach/pdp/cg/mach.h
index 4c2395f18..dbbdf8f86 100644
--- a/mach/pdp/cg/mach.h
+++ b/mach/pdp/cg/mach.h
@@ -23,7 +23,7 @@
 #define newilb(x)	fprintf(codefile,"%s:\n",x)
 #define newdlb(x)	fprintf(codefile,"%s:\n",x)
 #ifdef ACK_ASS
-#define newlbss(l,x)	fprintf(codefile,"%s:.space 0%o\n",l,x);
+#define newlbss(l,x)	fprintf(codefile,".comm %s,%u\n",l,x);
 #else
 #define newlbss(l,x)	fprintf(codefile,"%s:.=.+0%o\n",l,x);
 #endif
diff --git a/mach/pdp/ncg/mach.h b/mach/pdp/ncg/mach.h
index 4c2395f18..dbbdf8f86 100644
--- a/mach/pdp/ncg/mach.h
+++ b/mach/pdp/ncg/mach.h
@@ -23,7 +23,7 @@
 #define newilb(x)	fprintf(codefile,"%s:\n",x)
 #define newdlb(x)	fprintf(codefile,"%s:\n",x)
 #ifdef ACK_ASS
-#define newlbss(l,x)	fprintf(codefile,"%s:.space 0%o\n",l,x);
+#define newlbss(l,x)	fprintf(codefile,".comm %s,%u\n",l,x);
 #else
 #define newlbss(l,x)	fprintf(codefile,"%s:.=.+0%o\n",l,x);
 #endif
diff --git a/mach/z80/cg/mach.h b/mach/z80/cg/mach.h
index 779de8543..8adfc5538 100644
--- a/mach/z80/cg/mach.h
+++ b/mach/z80/cg/mach.h
@@ -12,7 +12,7 @@
 #define newilb(x)       fprintf(codefile,"%s:\n",x)
 #define newdlb(x)       fprintf(codefile,"%s:\n",x)
 #define dlbdlb(x,y)     fprintf(codefile,"%s = %s\n",x,y)
-#define newlbss(l,x)       fprintf(codefile,"%s:.space\t%d\n",l,x);
+#define newlbss(l,x)    fprintf(codefile,".comm %s,%u\n",l,x);
 
 #define cst_fmt         "%d"
 #define off_fmt         "%d"
diff --git a/mach/z8000/cg/mach.h b/mach/z8000/cg/mach.h
index bff94ee8c..23cbb840a 100644
--- a/mach/z8000/cg/mach.h
+++ b/mach/z8000/cg/mach.h
@@ -9,7 +9,7 @@
 #define newilb(x)       fprintf(codefile,"%s:\n",x)
 #define newdlb(x)       fprintf(codefile,"%s:\n",x)
 #define dlbdlb(x,y)     fprintf(codefile,"%s = %s\n",x,y)
-#define newlbss(l,x)    fprintf(codefile,"%s:\t.space %d\n",l,x);
+#define newlbss(l,x)    fprintf(codefile,".comm %s,%u\n",l,x);
 
 #define cst_fmt         "%d"
 #define off_fmt         "%d"