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From: "hpa at zytor dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c/39252] Request new feature __builtin_not_reached();
Date: Thu, 19 Feb 2009 22:21:00 -0000	[thread overview]
Message-ID: <20090219222143.17235.qmail@sourceware.org> (raw)
In-Reply-To: <bug-39252-3556@http.gcc.gnu.org/bugzilla/>



------- Comment #5 from hpa at zytor dot com  2009-02-19 22:21 -------
Let me respectfully disagree, and explain why.

*You* can just create a builtin, but for us (the Linux kernel community) we
stare a multi-year pipeline in the face whenever we have to request a gcc
change.  This feature would allow us to do arbitrary trapping constructs via
the existing generic asm feature, without having to do wait for this pipeline
to flush every time we want to do something new.

In theory, ALL asm() constructs could be turned into builtins, and on some
level, that would be the right thing to do.  However, I think you can see why
this is completely unrealistic, at least with anything less than us forking gcc
and have an ad hoc compiler for the kernel.

Yes, this feature can be abused.  So can *any* use of asm().


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39252


  parent reply	other threads:[~2009-02-19 22:21 UTC|newest]

Thread overview: 17+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-02-19 20:42 [Bug c/39252] New: " hpa at zytor dot com
2009-02-19 20:46 ` [Bug c/39252] " hjl dot tools at gmail dot com
2009-02-19 20:51 ` hjl dot tools at gmail dot com
2009-02-19 21:50 ` pinskia at gcc dot gnu dot org
2009-02-19 21:58 ` hpa at zytor dot com
2009-02-19 22:13 ` hpa at zytor dot com
2009-02-19 22:14 ` pinskia at gcc dot gnu dot org
2009-02-19 22:21 ` hpa at zytor dot com [this message]
2009-02-19 23:02 ` jakub at gcc dot gnu dot org
2009-02-20  4:34 ` hpa at zytor dot com
2009-02-20  9:57 ` rguenth at gcc dot gnu dot org
2009-03-01 22:34 ` hpa at zytor dot com
2009-03-01 22:42 ` rguenth at gcc dot gnu dot org
2009-06-09 20:12 ` daney at gcc dot gnu dot org
2009-06-09 20:16 ` daney at gcc dot gnu dot org
2009-06-11 23:56 ` [Bug c/39252] Request new feature __builtin_unreachable () daney at gcc dot gnu dot org
2009-06-12  0:29 ` daney at gcc dot gnu dot org

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