On 9/28/07, Kyle Moffett <[EMAIL PROTECTED]> wrote:
> On Sep 28, 2007, at 03:31:11, Geert Uytterhoeven wrote:
> > Can't you store the loglevel in the kprint_block and check it in
> > all successive kprint_*() macros? If gcc knows it's constant, it
> > can optimize the non-wanted code away. As other fields in struct
> > kprint_block cannot be constant (they store internal state), you
> > have to split it like:
> >
> > struct kprint_block {
> > int loglevel;
> > struct real_kprint_block real; /* internal state */
> > }
> >
> > and pass &block.real() instead of &block to all successive internal
> > functions. I haven't tried this, so let's hope gcc is actually
> > smart enough...
>
> Well actually, I believe you could just do:
>
> struct kprint_block {
> const int loglevel;
> [...];
> };
>
> Then cast away the constness to actually set it initially:
> *((int *)&block.loglevel) = LOGLEVEL;
This doesn't seem to work either (i.e. it is not optimized out). I
tried initializing the struct statically too, to no avail. But thanks
for the tip.
Vegard
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