Re: [PATCH] staging: rtl8723bs: Replace `& 0xfff` with `% 4096u`

On Fri, Apr 11, 2025 at 03:47:40PM +0300, Andy Shevchenko wrote:
> On Fri, Apr 11, 2025 at 1:37 PM Dan Carpenter <[email protected]> wrote:
> > On Thu, Apr 10, 2025 at 08:43:53PM +0300, Andy Shevchenko wrote:
> > >
> > > > $ make drivers/staging/rtl8723bs/core/rtw_xmit.o
> > > > $ cmp rtw_xmit_before.o rtw_xmit_after.o
> > >
> > > cmp is good but not good enough in general. Here it shows the 1:1
> > > binary, but in some cases code can be the same, while binaries are
> > > different. To make sure the code is the same use the bloat-o-meter
> > > tool instead.
> >
> > I don't understand what you're saying at all.  cmp shows that the compiler
> > was automaticall tanslating the "& 0xfff" into "% 04096u" so the resulting
> > object files are exactly the same.
> 
> There is a possibility that the compiler changes the code to the
> equivalent and cmp will break, bloat-o-meter will check at least what
> happened to the size of the *code*. object file is not only a code. It
> may also contain debug symbols and other stuff which may break cmp,
> while the code can be *the same*.

So far as I can see bloat-o-meter is only looking at the size.  I
deliberately introduced a bug to see if bloat-o-meter said anything but
it said the size was the same.

regards,
dan carpenter