Re: kern/51450 (tcptraceroute stopped working properly in 6.0 -> 7.0 transition)

[Havard Eidnes <he%NetBSD.org@localhost>]

>> Problem fixed; was wrong types in evel/libnet10 (not explictly sized),
>> causing an LP64 bug.  So not a kern bug after all.
> 
> Are the relevant struct packed?  If not, might there be other
> instances of this issue caused by target-dependent struct
> padding?  For example, I remember that the default alignment
> for some data types (like int64_t) is different on Intel than
> on RISC processors.

The structs were not packed.  Inside our source tree, <sys/cdefs.h>
defines __packed for this purpose, while outside our source tree (as
here), it's a little more sketchy.  Therefore I've locally added

+/* If you've not made __packed visible yet, too bad... */
+#ifndef __packed
+#define __packed       /* ignore */
+#endif
+

to that header and marked all the structs with __packed; should I
commit that update as well?

Not that it would make any difference for any of our platforms,
since the conversion I did was

u_long -> uin32_t
u_short -> uint16_t

and I left u_char alone, even though it could be replaced with
uint8_t.  Anyway, differences in alignment rules for 64-bit types
don't actually factor into the equation here.

Regards,

- Håvard