Treat warnings as errors for ARM target builds.

Change-Id: Icbc4867a001f33abebb759ddcc69dd877950b69a
diff --git a/vm/Dvm.mk b/vm/Dvm.mk
index c9e122e..8f421d4 100644
--- a/vm/Dvm.mk
+++ b/vm/Dvm.mk
@@ -273,6 +273,7 @@
 ifeq ($(dvm_arch),arm)
   #dvm_arch_variant := armv7-a
   #LOCAL_CFLAGS += -march=armv7-a -mfloat-abi=softfp -mfpu=vfp
+  LOCAL_CFLAGS += -Werror
   MTERP_ARCH_KNOWN := true
   # Select architecture-specific sources (armv4t, armv5te etc.)
   LOCAL_SRC_FILES += \