diff --git a/io.c b/io.c
index b6c6157598..10d512a58b 100644
--- a/io.c
+++ b/io.c
@@ -5494,8 +5494,10 @@ pipe_open(struct rb_exec_arg *eargp, VALUE prog, const char *modestr, int fmode,
     int write_fd = -1;
 #if !defined(HAVE_FORK)
     const char *cmd = 0;
+#if !defined(_WIN32)
     int argc;
     VALUE *argv;
+#endif
 
     if (prog)
         cmd = StringValueCStr(prog);
diff --git a/process.c b/process.c
index 8ccfe82995..57e1ed076b 100644
--- a/process.c
+++ b/process.c
@@ -3131,8 +3131,6 @@ rb_spawn_process(struct rb_exec_arg *earg, VALUE prog, char *errmsg, size_t errm
 #endif
 #if !defined HAVE_FORK || USE_SPAWNV
     struct rb_exec_arg sarg;
-    int argc;
-    VALUE *argv;
 #endif
 
 #if defined HAVE_FORK && !USE_SPAWNV