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Date: Wed, 25 Apr 2012 18:52:00 -0000
From: "Maciej W. Rozycki" <macro@codesourcery.com>
To: Sterling Augustine <saugustine@google.com>
CC: Andreas Schwab <schwab@linux-m68k.org>, Tom Tromey <tromey@redhat.com>,	Sergio Durigan Junior <sergiodj@redhat.com>, Jan Kratochvil	<jan.kratochvil@redhat.com>, <gdb@sourceware.org>
Subject: Re: Switch -Wunused-variable on?
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On Wed, 25 Apr 2012, Sterling Augustine wrote:

> >>  Then you don't actually need a definition, because the call will be
> >> optimised away
> >
> > You still need to support unoptimized builds.
> 
> GCC eliminates the unreachable block of an "if (0)" even without
> optimization. Many other compilers don't. It is an ongoing source of
> complications for getting compilers other than GCC to build the linux
> kernel which uses this approach extensively.

 That sounds silly, I didn't know that.  In this case a "static inline" 
dummy function would have to be provided indeed that makes the solution a 
bit less elegant then I would like it to be.  Still probably better than a 
maze of #ifdefs scattered throughout code, but YMMV.

  Maciej