From mboxrd@z Thu Jan  1 00:00:00 1970
Message-ID: <9c9d07436eff1c038450ca310ea13a7a@plan9.jp>
To: 9fans@cse.psu.edu
From: Joel Salomon <JoelCSalomon@Gmail.com>
Date: Tue, 20 Feb 2007 18:55:31 -0500
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Subject: [9fans] NaN(2)
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My system doesn=E2=80=99t seem to like it when I call NaN(2):

cpu% cat tnan.c
#include <u.h>
#include <libc.h>

void
main(int, char**)
{
	double d =3D NaN();
	print("d =3D %f\n", d);

	exits(0);
}
cpu% 8c -FVw tnan.c
cpu% 8l tnan.8
cpu% 8.out
8.out 55798: suicide: sys: fp: invalid operation fppc=3D0x10a4 status=3D0=
x8081 pc=3D0x00001028
cpu% acid 55798
/proc/55798/text:386 plan 9 executable

/sys/lib/acid/port
/sys/lib/acid/386
acid: stk()
main()+0x8 /usr/chesky/src/hak/lex/tnan.c:7
_main+0x31 /sys/src/libc/386/main9.s:16
acid: asm(main)
main 0x00001020	SUBL	$0x1c,SP
main+0x3 0x00001023	CALL	NaN(SB)
main+0x8 0x00001028	FMOVDP	F0,d+0x14(SP)
=E2=80=A6

Why is this happening?

Also, what is Intel=E2=80=99s name for the FMOVDP instruction?

--Joel