From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jesper Skov <jskov@redhat.com>
To: ecos-discuss@sourceware.cygnus.com
Subject: Re: [ECOS] RedBoot sending incorrect TCP window size
Date: Fri, 09 Feb 2001 06:00:00 -0000
Message-id: <ww4itmkvuix.fsf@host176.cambridge.redhat.com>
References: <20010208105133.A1381@visi.com> <3A82FE61.7F6F2EE8@ri.silicomp.fr> <20010208145836.A2740@visi.com> <200102091340.f19De5J22761@sheesh.cambridge.redhat.com>
X-SW-Source: 2001-02/msg00142.html

>>>>> "Bart" == Bart Veer <bartv@redhat.com> writes:
Bart> Possibly there should be a gcc extension __packed_sizeof(),
Bart> returning a number that excludes external padding. This would
Bart> not be a complete solution: people would still use sizeof() in a
Bart> non-portable fashion.  However it might make it easier to write
Bart> portable code.

IIRC GCC treats one-off struct variables different from arrays of the
same struct. So you may have something like:

typedef struct {
  int  foo;
  char bar;
} __attribute__ ((packed)) icky;

icky a;
icky b[10];

sizeof(a) == 5
sizeof(b[0]) == 8

Or something to that effect (*hand wave*)

Jesper