diff --git a/mach/arm/ncg/table b/mach/arm/ncg/table
index db841361b..07931553c 100644
--- a/mach/arm/ncg/table
+++ b/mach/arm/ncg/table
@@ -2172,6 +2172,7 @@ pat lor $1==2				yields {absolute, "_RegHp"}
 pat lpb					leaving adp 8
 
 pat nop
+kills ALL
 gen MOV_NV R0,R0
 
 pat rck
diff --git a/mach/i386/ncg/table b/mach/i386/ncg/table
index 5bd7c5d00..22a76e2fd 100644
--- a/mach/i386/ncg/table
+++ b/mach/i386/ncg/table
@@ -2746,7 +2746,9 @@ kills ALL
 
 pat nop
 kills ALL
-  /* gen proccall {label, ".nop"} */
+#ifdef DEBUG
+  gen proccall {label, ".nop"}
+#endif
 
 pat rck $1==4
 with BXREG ACC
diff --git a/mach/i80/ncg/table b/mach/i80/ncg/table
index 8e210b3cc..3648a0c97 100644
--- a/mach/i80/ncg/table
+++ b/mach/i80/ncg/table
@@ -2035,7 +2035,9 @@ gen Call {label,".mon"}
 
 pat nop
 kills ALL
+#ifdef DEBUG
 gen Call {label,".nop"}
+#endif
 
 pat rck
 with hl_or_de STACK
diff --git a/mach/i86/ncg/table b/mach/i86/ncg/table
index 16472814d..b806674e7 100644
--- a/mach/i86/ncg/table
+++ b/mach/i86/ncg/table
@@ -3288,7 +3288,7 @@ kills ALL
 
 pat nop
 kills ALL
-#if 0
+#if DEBUG
   gen joehoe {label, ".nop"}
 #endif
 
diff --git a/mach/m68020/ncg/table b/mach/m68020/ncg/table
index 97e20fa0d..b0f3649c3 100644
--- a/mach/m68020/ncg/table
+++ b/mach/m68020/ncg/table
@@ -5872,11 +5872,12 @@ with STACK
     kills ALL
     gen jsr {absolute4, ".mon"}
 
-/* used by the ANSI-compiler to indicate volatile */
 pat nop
 with STACK
     kills ALL
-/*     gen jsr {absolute4, ".nop"} */
+#ifdef DEBUG
+    gen jsr {absolute4, ".nop"}
+#endif
 
 #if WORD_SIZE==2
 pat rck $1==2
diff --git a/mach/m68k2/ncg/table b/mach/m68k2/ncg/table
index 97e20fa0d..b0f3649c3 100644
--- a/mach/m68k2/ncg/table
+++ b/mach/m68k2/ncg/table
@@ -5872,11 +5872,12 @@ with STACK
     kills ALL
     gen jsr {absolute4, ".mon"}
 
-/* used by the ANSI-compiler to indicate volatile */
 pat nop
 with STACK
     kills ALL
-/*     gen jsr {absolute4, ".nop"} */
+#ifdef DEBUG
+    gen jsr {absolute4, ".nop"}
+#endif
 
 #if WORD_SIZE==2
 pat rck $1==2
diff --git a/mach/m68k4/ncg/table b/mach/m68k4/ncg/table
index 97e20fa0d..b0f3649c3 100644
--- a/mach/m68k4/ncg/table
+++ b/mach/m68k4/ncg/table
@@ -5872,11 +5872,12 @@ with STACK
     kills ALL
     gen jsr {absolute4, ".mon"}
 
-/* used by the ANSI-compiler to indicate volatile */
 pat nop
 with STACK
     kills ALL
-/*     gen jsr {absolute4, ".nop"} */
+#ifdef DEBUG
+    gen jsr {absolute4, ".nop"}
+#endif
 
 #if WORD_SIZE==2
 pat rck $1==2
diff --git a/mach/moon3/ncg/table b/mach/moon3/ncg/table
index 97e20fa0d..b0f3649c3 100644
--- a/mach/moon3/ncg/table
+++ b/mach/moon3/ncg/table
@@ -5872,11 +5872,12 @@ with STACK
     kills ALL
     gen jsr {absolute4, ".mon"}
 
-/* used by the ANSI-compiler to indicate volatile */
 pat nop
 with STACK
     kills ALL
-/*     gen jsr {absolute4, ".nop"} */
+#ifdef DEBUG
+    gen jsr {absolute4, ".nop"}
+#endif
 
 #if WORD_SIZE==2
 pat rck $1==2
diff --git a/mach/ns/ncg/table b/mach/ns/ncg/table
index 9df0785c8..ed84a74cf 100644
--- a/mach/ns/ncg/table
+++ b/mach/ns/ncg/table
@@ -2227,9 +2227,11 @@ gen jsr {absolute4, ".mon"}
 
 pat nop
 kills ALL
+#ifdef DEBUG
     gen move {absolute4, "hol0"}, {TOS}
 	jsr {absolute4, ".print"}
 	jsr {absolute4, ".prnl"}
+#endif
 
 pat rck $1==4
 kills ALL
diff --git a/mach/pdp/cg/table b/mach/pdp/cg/table
index 9e61e2d1b..389258901 100644
--- a/mach/pdp/cg/table
+++ b/mach/pdp/cg/table
@@ -2675,7 +2675,10 @@ lor $1==2       | |     			| {relative2,"reghp~"}  | |
 mon             | |     remove(all)
 			"jsr pc,mon~"                   |       | |
 nop             | |     remove(all)
-			"jsr pc,nop~"                   |       | |
+#ifdef DEBUG
+			"jsr pc,nop~"
+#endif
+							|       | |
 #ifdef DORCK
 rck $1==2       | source2 |
 			remove(all)
diff --git a/mach/pdp/ncg/table b/mach/pdp/ncg/table
index 508a78c64..dea4500f1 100644
--- a/mach/pdp/ncg/table
+++ b/mach/pdp/ncg/table
@@ -2190,7 +2190,9 @@ gen jsr pc,{label, "mon~"}
 
 pat nop
 kills ALL
+#ifdef DEBUG
 gen jsr pc,{label, "nop~"}
+#endif
 
 pat rck $1==2
 with src2
diff --git a/mach/vax4/cg/table b/mach/vax4/cg/table
index 4f0c3d8cf..b7b71c54f 100644
--- a/mach/vax4/cg/table
+++ b/mach/vax4/cg/table
@@ -4454,7 +4454,7 @@ lpb		| bigsource4 |
 mon		| STACK |
 			"jsb\t.mon"		|	| |
 nop		| STACK |
-#ifdef TESTING
+#ifdef DEBUG
 			"jsb\t.nop"
 #endif
 						|	| |
diff --git a/mach/z8000/cg/table b/mach/z8000/cg/table
index 5a2ac0229..7439930c3 100644
--- a/mach/z8000/cg/table
+++ b/mach/z8000/cg/table
@@ -1711,7 +1711,7 @@ mon	| STACK	| "calr mon"	| | |
 nop	| STACK	|
 #ifdef DEBUG
 	"calr noop"
-#ENDIF
+#endif
 					| | |
 rtt	| | | | ret 0	|
 sig	| REG	| allocate(REG)