🚀 go-pugleaf

In article <162@eliza.edvvie.at> johnny@edvvie.at (Johann Schweigl) writes:
>[... Integers must be word-aligned on an RT...]
>
>[ ... but not on a '386 ...]
>...
>This leads me to the final questions: 
>- is it acceptable that the CPU changes the adress you delivered without any
>  warning and does something you wouldn't expect
>- how do other CPU's behave (eg. 88000, 68000, SPARC, MIPS)
>- would you prefer getting an 'alignment violation trap' or something like this
>- does any CPU implement such a trap
>

The full-word alignment restriction is due to the hardware design. The
last time I looked at this problem (someone's program was dying with
the usual "bus error, core dumped" message), I recall that AIX trapped
the error and produced the message (rather than altering the
destination address so things worked). It may be that under the current
release of AIX the kernel traps the error and patches things so they
work, albeit apparently incorrectly. If the is the case, you should
report the problem to IBM.

The restriction, I am told, is very common for RISC processors. To wit, I
believe that SUN SPARCstations have the same "problem".

	-- David