Yesterday night I wrote

> Note: this is not yet a confirmed compiler bug

but in the meantime there is good confirmation.
This really is a bug in gcc 2.95.2.

>From [EMAIL PROTECTED] Thu Nov 23 10:45:07 2000
> Please, could you send me ...

>From [EMAIL PROTECTED] Thu Nov 23 18:00:48 2000
> Can we get a show of hands?

Below a demo program.

Andries

-------------------- bug.c -----------------------------
/*
 * bug.c - aeb, 001124
 *
 * This program shows a bug in gcc 2.95.2.
 * It should print 0x0 and exit.
 * For me it prints 0x84800000.
 *
 * Compile with:
 *    gcc -Wall -O2 -o bug bug.c
 */
#include <stdio.h>

struct inode {
        long long               i_size;
        struct super_block      *i_sb;
};

struct file {
        long long               f_pos;
};

struct super_block {
        int                     s_blocksize;
        unsigned char           s_blocksize_bits;
        int                     s_hs;
};

static char *
isofs_bread(unsigned int block)
{
        printf("0x%x\n", block);
        exit(0);
}

static int
do_isofs_readdir(struct inode *inode, struct file *filp)
{
        int bufsize = inode->i_sb->s_blocksize;
        unsigned char bufbits = inode->i_sb->s_blocksize_bits;
        unsigned int block, offset;
        char *bh = NULL;
        int hs;

        if (filp->f_pos >= inode->i_size)
                return 0;
 
        offset = filp->f_pos & (bufsize - 1);
        block = filp->f_pos >> bufbits;
        hs = inode->i_sb->s_hs;

        while (filp->f_pos < inode->i_size) {
                if (!bh)
                        bh = isofs_bread(block);

                hs += block << bufbits;

                if (hs == 0)
                        filp->f_pos++;

                if (offset >= bufsize)
                        offset &= bufsize - 1;

                if (*bh)
                        filp->f_pos++;

                filp->f_pos++;
        }
        return 0;
}

struct super_block s;
struct inode i;
struct file f;

int
main(int argc, char **argv){
        s.s_blocksize = 512;
        s.s_blocksize_bits = 9;
        i.i_size = 2048;
        i.i_sb = &s;
        f.f_pos = 0;

        do_isofs_readdir(&i,&f);
        return 0;
}
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