From mboxrd@z Thu Jan  1 00:00:00 1970
Message-ID: <1ebc06ba0079a91546444a93ab21bc65@quintile.net>
From: "Steve Simon" <steve@quintile.net>
Date: Wed, 27 Nov 2013 16:03:52 +0000
To: 9fans@9fans.net
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Subject: [9fans] compiler bug?
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Whilst porting some code from the net I came across
the attached, rather obscure, code.

run as:

	larch% 8c -D 'STATIC=static' t.c && 8l t.8 && 8.out
	78780000
	larch% 8c -D 'STATIC=' t.c && 8l t.8 && 8.out
	0

I think it is tickling a bug in 8c, though
I may be just showing my lack of knowledge of
the C standard...

anyone any thoughts?

-Steve
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#include <u.h>
#include <libc.h>

static uint getdword_n(void *mem, int n)
{
    STATIC uint tmp = 0;

    switch (n)
    {
    case 3:
        ((uchar*)&tmp)[1] = ((uchar*)mem)[2];
    case 2:
        ((uchar*)&tmp)[2] = ((uchar*)mem)[1];
    case 1:
        ((uchar*)&tmp)[3] = ((uchar*)mem)[0];
    default:
        break;
    }

    return tmp;
}

void
main(void)
{
	uint x;

	char buf[] = "xxxx";

	x = getdword_n(buf, 2);
	print("%x\n", x);
}
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