diff --git a/build.config.x86_64 b/build.config.x86_64
index b16ac8a68b25..cc3c66e7d3d5 100644
--- a/build.config.x86_64
+++ b/build.config.x86_64
@@ -1,5 +1,6 @@
 ARCH=x86_64
 
+LLVM_IAS=1
 CROSS_COMPILE=x86_64-linux-gnu-
 LINUX_GCC_CROSS_COMPILE_PREBUILTS_BIN=prebuilts/gas/linux-x86