diff --git a/Android.mk b/Android.mk
index c69a2cc..bf37672 100644
--- a/Android.mk
+++ b/Android.mk
@@ -18,14 +18,9 @@
 BASE_PATH := $(call my-dir)
 include $(CLEAR_VARS)
 
-# Two ways to control which JS engine is used:
-# 1. use JS_ENGINE environment variable, value can be either 'jsc' or 'v8'
-#    This is the preferred way.
-# 2. if JS_ENGINE is not set, or is not 'jsc' or 'v8', this makefile picks
-#    up a default engine to build.
-#    To help setup buildbot, a new environment variable, USE_ALT_JS_ENGINE,
-#    can be set to true, so that two builds can be different but without
-#    specifying which JS engine to use.
+ifneq ($(strip $(ARCH_ARM_HAVE_ARMV7A)),true)
+  $(error V8 requires ARM v7)
+endif
 
 # Build libv8 and v8shell
 ifeq ($(TARGET_ARCH),arm)