diff --git a/targets/esp8266.json b/targets/esp8266.json
index c0c7ad3f..593d0769 100644
--- a/targets/esp8266.json
+++ b/targets/esp8266.json
@@ -8,6 +8,7 @@
 	"cflags": [
 		"-mcpu=esp8266"
 	],
+	"rtlib": "compiler-rt",
 	"linkerscript": "targets/esp8266.ld",
 	"extra-files": [
 		"src/device/esp/esp8266.S",