1 files changed, 1 insertions, 1 deletions
diff --git a/eval.c b/eval.c
index 60d2b46a3c..d00891aa13 100644
--- a/eval.c
+++ b/eval.c
@@ -10296,7 +10296,7 @@ rb_thread_switch(n)
 
 NORETURN(static void rb_thread_restore_context _((rb_thread_t,int)));
 
-# if _MSC_VER >= 1300
+# if defined(_MSC_VER) && _MSC_VER >= 1300
 __declspec(noinline) static void stack_extend(rb_thread_t, int);
 # endif
 static void