diff --git a/compiler/optimizing/optimizing_compiler.cc b/compiler/optimizing/optimizing_compiler.cc
index a1da20b..698b0b6 100644
--- a/compiler/optimizing/optimizing_compiler.cc
+++ b/compiler/optimizing/optimizing_compiler.cc
@@ -833,9 +833,7 @@
 
   // Always use the Thumb-2 assembler: some runtime functionality
   // (like implicit stack overflow checks) assume Thumb-2.
-  if (instruction_set == kArm) {
-    instruction_set = kThumb2;
-  }
+  DCHECK_NE(instruction_set, kArm);
 
   // Do not attempt to compile on architectures we do not support.
   if (!IsInstructionSetSupported(instruction_set)) {