have_header: checking for windows.h... -------------------- yes

"cl -I. -Ie:/ruby/lib/ruby/1.8/i386-mswin32  -MD -Zi -O2b2xg- -G6  conftest.c -P"
Microsoft (R) 32-bit C/C++ Standard Compiler Version 13.10.3077 for 80x86
Copyright (C) Microsoft Corporation 1984-2002. All rights reserved.

cl : Command line warning D4029 : optimization is not available in the standard edition compiler
cl : Command line warning D4002 : ignoring unknown option '-Og-'
conftest.c
checked program was:
/* begin */
#include <windows.h>
/* end */

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