diff --git a/src/helper/jim.c b/src/helper/jim.c
index 7f21b4304..5da0aa114 100644
--- a/src/helper/jim.c
+++ b/src/helper/jim.c
@@ -11979,7 +11979,7 @@ static int Jim_EnvCoreCommand(Jim_Interp *interp, int argc,
 
     if (argc == 1) {
 
-#if !defined(_WIN32) && !defined(__USE_GNU)
+#ifndef HAVE_UNISTD_H
         extern char **environ;
 #endif