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From: Nikita Danilov <Nikita@Namesys.COM>
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Date: Wed, 17 Apr 2002 18:29:00 +0400
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To: Andrey Ulanov <drey@rt.mipt.ru>
Cc: linux-kernel@vger.kernel.org
Subject: Re: FPU, i386
In-Reply-To: <20020417140510.GB9930@gleam.rt.mipt.ru>
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Andrey Ulanov writes:
 > Look at this:
 > 
 > $ cat test.c
 > #include <stdio.h>
 > 
 > main()
 > {
 > 	double h = 0.2;
 > 	
 > 	if(1/h == 5.0)
 > 	    printf("1/h == 5.0\n");
 > 
 > 	if(1/h < 5.0)
 > 	    printf("1/h < 5.0\n");
 > 	return 0;
 > }
 > $ gcc test.c

$ gcc -O test.c
$ ./a.out
1/h == 5.0

without -O, gcc initializes h to 0.2000000000000000111

 > $ ./a.out
 > 1/h < 5.0
 > $ 
 > 
 > I also ran same a.out under FreeBSD. It says "1/h == 5.0".
 > It seems there is difference somewhere in FPU 
 > initialization code. And I think it should be fixed.
 > 
 > ps. cc to me
 > -- 
 > with best regards, Andrey Ulanov.
 > drey@rt.mipt.ru
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