linux-2.3.3 doesn't boot when compiled with egcs-2.93.22

[Martin v. Loewis]

> void main_function(struct tcphdr *th)
> {
> 	... do something with th ...
> 	function_that_plays_tricks((struct tcphdr_union *) th); 
> 	... do something with th ...
> }
> 
> Is this ok?

As Jeff points out: Technically, this is undefined for ISO C. GNU C
will understand it even under strict aliasing. Please see the
documentation for -fstrict-aliasing for details.

Regards,
Martin