diff --git a/src/arch/arm/isa/decoder/arm.isa b/src/arch/arm/isa/decoder/arm.isa
index 29ec46f9b..3f43b23e1 100644
--- a/src/arch/arm/isa/decoder/arm.isa
+++ b/src/arch/arm/isa/decoder/arm.isa
@@ -50,7 +50,7 @@
 //
 //
 
-0: decode COND_CODE {
+decode COND_CODE {
 0xF: ArmUnconditional::armUnconditional();
 default: decode ENCODING {
 format DataOp {
diff --git a/src/arch/arm/isa/decoder/decoder.isa b/src/arch/arm/isa/decoder/decoder.isa
index e88a18d3b..cf7d17871 100644
--- a/src/arch/arm/isa/decoder/decoder.isa
+++ b/src/arch/arm/isa/decoder/decoder.isa
@@ -41,6 +41,8 @@
 // Authors: Gabe Black
 
 decode THUMB default Unknown::unknown() {
+0:
 ##include "arm.isa"
+1:
 ##include "thumb.isa"
 }
diff --git a/src/arch/arm/isa/decoder/thumb.isa b/src/arch/arm/isa/decoder/thumb.isa
index 6c1dd7d57..3799bdf1f 100644
--- a/src/arch/arm/isa/decoder/thumb.isa
+++ b/src/arch/arm/isa/decoder/thumb.isa
@@ -40,7 +40,7 @@
 //
 // Authors: Gabe Black
 
-1: decode BIGTHUMB {
+decode BIGTHUMB {
     // 16 bit thumb instructions.
     0: decode TOPCODE_15_13 {
         0x0, 0x1: Thumb16ShiftAddSubMoveCmp::thumb16ShiftAddMoveCmp();