> > The offender is almost certainly the 'generic expander'.
>
> I tried to make a simpler example which reproduces the same error:
>
> *****************************************************************
>
> target memsize 8 byteorder little pointersize 32 wordsize 32;
>
> export main;
>
> foo (bits64 x) {
> return (%and(x,1::bits64));
> }
>
> foreign "C" main (bits32 argc, "address" bits32 argv) {
> foo (10::bits64);
> foreign "C" return (0);
> }
>
> *****************************************************************
>
> $ qc-- -globals simple.c--
> This can't happen: Asked for temporary in space `general-purpose
> temporaries' with unsupported width 64
> Fatal error: exception Impossible.Impossible("Asked for temporary in space
> `general-purpose temporaries' with unsupported width 64")
>
> *****************************************************************
Thanks for the nice clean bug report. Undoubtedly what is happening
is that the generic expander is asking for a 64-bit temporary to help
move the literal 10 where 64-bit parameters go. Of course what it
*should* do is split the 64-bit literal into two 32-bit literals.
Rather than tackle this sort of problem piecemeal, we are hoping to
replace the generic expander with a new 'tiler', which will have a
more principled approach to this problem, and in particular we should
be able to prove that either this problem does not occur or that it is
detected in advance. The solution to this problem is worth a good
chunk of a PhD thesis, so it may have to wait until I find a
student...
Norman
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