unalligned sparc memory access problem (memcpy vs bcopy)

[Bernd Eckenfels <lists@lina.inka.de>]

Hello,

I just fixed net-acct to work on sparc (removed a sigbus and some endianess
problems). I noticed that: tmp_iphdr->saddr access needs to be changed into
a memory copy operation because the values are not alligned. Problem: it
works with bcopy, but memcpy still gets an sigbus:

this works:

    bcopy(&(tmp_iphdr->saddr), &tmpsrc, sizeof(tmpsrc));

this will give me sigbus:

    memcpy(&tmpsrc, &(tmp_iphdr->saddr), sizeof(tmpsrc));

Is it right, that memcpy is unable to deal with unalligned start address?

This is gcc on autic:

Reading specs from /usr/lib/gcc-lib/sparc-linux/2.95.2/specs
gcc version 2.95.2 20000220 (Debian GNU/Linux)

ecki@auric:~/net-acct-0.71$ ldd src/nacctd
        libc.so.6 => /lib/libc.so.6 (0x7002c000)
        /lib/ld-linux.so.2 => /lib/ld-linux.so.2 (0x70000000)

There is nothing in the man page which describes this problem of memcpy, in
fact I found a few postings on the net, and all of them where recommending
to use memcpy to access members of badly alligned ip-header structures.

Greetings
Bernd
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