diff --git a/cores/esp8266/abi.cpp b/cores/esp8266/abi.cpp
index 7eadfad10..674667776 100644
--- a/cores/esp8266/abi.cpp
+++ b/cores/esp8266/abi.cpp
@@ -58,4 +58,6 @@ namespace std {
   }
 }
 
+// TODO: rebuild windows toolchain to make this unnecessary:
+void* __dso_handle;