Probable Bug in tcp.h

[Bruce M. Simpson]

Marc Lörner wrote:
> th_x2 and th_off are created as a bitfield. But C-Standard says that bitfields 
> are accessed as integers => 4-bytes
>
> On itanium integers are read with ld4-command but the address of th_x2/th_off 
> may not be aligned to 4-bytes => we get an unaligned reference fault.
>
> If we'd change to 1 byte-accesses => I won't get any misaligned faults 
> anymore.
>   

It's worth noting that Linux implements its version of tcphdr using a 
32-bit-wide bitfield and the TCP header flags live there as bits instead 
of as integer quantities.

I think it should be OK to change the u_int to a uint8_t as NetBSD has. 
The problem with bitfields in "signed char" is that they can become 
unintentionally sign extended on a read, and for many years compilers 
only supported "char", not "unsigned char".

Does anyone see a reason why we should not make this change?