diff --git a/arch/arm/src/arm/arm_cache.S b/arch/arm/src/arm/arm_cache.S
index 53dd580f54..8b871365f0 100644
--- a/arch/arm/src/arm/arm_cache.S
+++ b/arch/arm/src/arm/arm_cache.S
@@ -37,6 +37,8 @@
  ****************************************************************************/
 
 	.text
+	.syntax	unified
+	.arm
 
 /* Control functions caches and the write buffer c7
  * Register c7 controls the caches and the write buffer. The function of each cache
diff --git a/arch/arm/src/arm/arm_head.S b/arch/arm/src/arm/arm_head.S
index 9d2f23ce2f..f7b55b6147 100644
--- a/arch/arm/src/arm/arm_head.S
+++ b/arch/arm/src/arm/arm_head.S
@@ -216,6 +216,8 @@
  */
 
 	.text
+	.syntax	unified
+	.arm
 	.global	__start
 	.type	__start, #function
 
diff --git a/arch/arm/src/arm/arm_nommuhead.S b/arch/arm/src/arm/arm_nommuhead.S
index f3ba484a3e..3570d8dad3 100644
--- a/arch/arm/src/arm/arm_nommuhead.S
+++ b/arch/arm/src/arm/arm_nommuhead.S
@@ -52,6 +52,8 @@
  * below.
  */
 	.text
+	.syntax	unified
+	.arm
 	.global __start
 	.type	__start, #function
 __start:
diff --git a/arch/arm/src/arm/arm_vectoraddrexcptn.S b/arch/arm/src/arm/arm_vectoraddrexcptn.S
index e0be37d2b6..5d32fd0341 100644
--- a/arch/arm/src/arm/arm_vectoraddrexcptn.S
+++ b/arch/arm/src/arm/arm_vectoraddrexcptn.S
@@ -46,12 +46,8 @@
  ****************************************************************************/
 
 	.text
-
-/****************************************************************************
- * Public Functions
- ****************************************************************************/
-
-	.text
+	.syntax	unified
+	.arm
 
 /****************************************************************************
  *  Name: arm_vectoraddrexcptn
diff --git a/arch/arm/src/arm/arm_vectors.S b/arch/arm/src/arm/arm_vectors.S
index fa30eed4dc..c1d234ceef 100644
--- a/arch/arm/src/arm/arm_vectors.S
+++ b/arch/arm/src/arm/arm_vectors.S
@@ -106,6 +106,8 @@
  ****************************************************************************/
 
 	.text
+	.syntax	unified
+	.arm
 
 /****************************************************************************
  * Public Functions
diff --git a/arch/arm/src/arm/arm_vectortab.S b/arch/arm/src/arm/arm_vectortab.S
index b2f6be8ce3..391a582d97 100644
--- a/arch/arm/src/arm/arm_vectortab.S
+++ b/arch/arm/src/arm/arm_vectortab.S
@@ -34,6 +34,9 @@
  * Public Symbols
  ****************************************************************************/
 
+	.syntax	unified
+	.arm
+
 	.globl	_vector_start
 	.globl	_vector_end