Re: [PATCH] middle-end/102360 - adjust .DEFERRED_INIT expansion

[Richard Biener via Gcc-patches]

On Thu, 16 Sep 2021, Jakub Jelinek wrote:

> On Thu, Sep 16, 2021 at 11:48:49AM +0200, Richard Biener via Gcc-patches 
> wrote:
> > 2021-09-16  Richard Biener  <rguent...@suse.de>
> > 
> >     PR middle-end/102360
> >     * internal-fn.c (expand_DEFERRED_INIT): Make pattern-init
> >     of non-memory more robust.
> > 
> >     * g++.dg/pr102360.C: New testcase.
> > +     if (can_native_interpret_type_p (var_type))
> > +       init = native_interpret_expr (var_type, buf, total_bytes);
> > +     else
> > +       {
> > +         tree itype = build_nonstandard_integer_type (total_bytes * 8, 1);
> 
> Shouldn't that 8 be BITS_PER_UNIT ?
> I know we have tons of problems with BITS_PER_UNIT is not 8, but adding
> further ones is unnecessary.

Well, a byte is 8 bits and we do

      unsigned HOST_WIDE_INT total_bytes
        = tree_to_uhwi (TYPE_SIZE_UNIT (var_type));

      if (init_type == AUTO_INIT_PATTERN)
        {
          unsigned char *buf = (unsigned char *) xmalloc (total_bytes);
          memset (buf, INIT_PATTERN_VALUE, total_bytes);

and thus mix host and target here.  I suppose it should be instead

   unsigned HOST_WIDE_INT total_bytes
     = tree_to_uhwi (TYPE_SIZE (var_type)) / (BITS_PER_UNIT / 8);

or so...  in this light * 8 for the build_nonstandard_integer_type
use is correct, no?  If total_bytes is really _bytes_.

Richard.