svn commit: r362217 - head/stand/common

[Rodney W. Grimes]

> In message <55903c38d363aef2a6f6d0075dd4526b86d51258.camel at freebsd.org>, 
> Ian Le
> pore writes:
> > On Tue, 2020-06-16 at 07:05 +0000, Toomas Soome wrote:
> > > Author: tsoome
> > > Date: Tue Jun 16 07:05:03 2020
> > > New Revision: 362217
> > > URL: https://svnweb.freebsd.org/changeset/base/362217
> > > 
> > > Log:
> > >   loader: variable i is unused without MBR/GPT support built in
> > >   
> > >   Because i is only used as index in for loop, declare it in for
> > > statement.
> > > 
> >
> > As much as I prefer doing it this way, style(9) doesn't allow for
> > variable declarations inside a for() statement (or even inside a local
> > block, which is just too 1980s for me, but it is still our standard).

Last time I tried to assert that bit of style(9) with respect to
inside a local block I was over ridden, so it is probably time
to atleast revisit that part of style(9).

> Doesn't this use stack for a shorter period of time or does the compiler 
> optimize this, making this change moot?
> 
> The tradeoff is a few extra bytes of stack for a longer period of time vs a 
> few extra instructions incrementing and decrementing the stack pointer.

I do not think the reasoning had to do with stack space vs instuctions,
but more about being able to clearly know about variable reuse and not
do it as that can create fun bugs.

Tools have modernized since that part of style was written.

> -- 
> Cy Schubert <Cy.Schubert at cschubert.com>
-- 
Rod Grimes                                                 rgrimes at freebsd.org