MINGW: Fix build error on Windows UCRT

win32/win32.c

@@ -887,6 +887,13 @@ socklist_delete(SOCKET *sockp, int *flagp)
     return ret;
 }
 
+#if RUBY_MSVCRT_VERSION >= 80
+# ifdef __MINGW32__
+#  define _CrtSetReportMode(type,mode) ((void)0)
+#  define _RTC_SetErrorFunc(func) ((void)0)
+# endif
+static void set_pioinfo_extra(void);
+#endif
 static int w32_cmdvector(const WCHAR *, char ***, UINT, rb_encoding *);
 //
 // Initialization stuff
@@ -896,7 +903,6 @@ void
 rb_w32_sysinit(int *argc, char ***argv)
 {
 #if RUBY_MSVCRT_VERSION >= 80
-    static void set_pioinfo_extra(void);
 
     _CrtSetReportMode(_CRT_ASSERT, 0);
     _set_invalid_parameter_handler(invalid_parameter);