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From: "bigotp at acm dot org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug middle-end/25140] aliases, including weakref, break alias analysis
Date: Fri, 13 Aug 2010 20:11:00 -0000 [thread overview]
Message-ID: <20100813201131.26251.qmail@sourceware.org> (raw)
In-Reply-To: <bug-25140-638@http.gcc.gnu.org/bugzilla/>
------- Comment #11 from bigotp at acm dot org 2010-08-13 20:11 -------
(In reply to comment #9)
> (In reply to comment #8)
> > Hm, I only can see references to "symbol" not to either function or variable
> > declaration in the documentation. Can you cite the part that makes you think
> > it restricts the use to functions?
>
> It's documented in the section on function attributes, but not listed in the
> section on variable attributes. Compare 'deprecated' or 'weak', which are
> listed in both places.
Is there any intention to restrict use of weakref to functions? It seems to
be exactly what I want to use to allow a translation unit to reference a
memory-mapped register by its vendor-defined name, while not making that
name a global symbol that impacts other translation units, nor providing the
actual register address until the final link phase:
static volatile uint16_t P1IN __attribute((weakref("__P1IN")));
uint16_t c3 () { return P1IN; }
with __P1IN = 0x0020; in a linker script.
Other approaches seem to require that I have a definition for __P1IN
available at the time the object file is generated, which means I'd have a
potential for conflict if a different object file happened to include a
header that gave the register a different address; or that I use:
volatile uint16_t P1IN __attribute((weak));
uint16_t c3 () { return P1IN; }
which clutters the namespace.
Heck, I'll submit a patch to gcc/doc/extend.texi that explicitly allows use
of weakref on variables if that'd help.
--
bigotp at acm dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |bigotp at acm dot org
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25140
next prev parent reply other threads:[~2010-08-13 20:11 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2005-11-28 17:03 [Bug middle-end/25140] New: " geoffk at gcc dot gnu dot org
2005-11-28 17:06 ` [Bug middle-end/25140] " pinskia at gcc dot gnu dot org
2005-11-28 18:40 ` aoliva at gcc dot gnu dot org
2005-11-28 19:22 ` geoffk at geoffk dot org
2005-11-29 13:55 ` aoliva at gcc dot gnu dot org
2005-11-30 1:01 ` geoffk at geoffk dot org
2009-09-26 11:29 ` rguenth at gcc dot gnu dot org
2009-09-26 11:51 ` geoffk at gcc dot gnu dot org
2009-09-26 12:01 ` rguenth at gcc dot gnu dot org
2009-09-26 12:15 ` geoffk at gcc dot gnu dot org
2010-05-09 16:50 ` rguenth at gcc dot gnu dot org
2010-08-13 20:11 ` bigotp at acm dot org [this message]
[not found] <bug-25140-4@http.gcc.gnu.org/bugzilla/>
2014-02-17 12:25 ` rguenth at gcc dot gnu.org
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