[Top] [All Lists]

Re: [PATCH] Discardable strings for init and exit sections

To: Adrian Bunk <>
Subject: Re: [PATCH] Discardable strings for init and exit sections
From: Ralf Baechle <>
Date: Fri, 12 Oct 2007 18:52:10 +0100
Cc: "Maciej W. Rozycki" <>, Franck Bui-Huu <>,,, Andrew Morton <>,
In-reply-to: <>
Original-recipient: rfc822;
References: <> <>
User-agent: Mutt/1.5.14 (2007-02-12)
On Fri, Oct 12, 2007 at 07:19:38PM +0200, Adrian Bunk wrote:

> I have an objection against this approach:
> Our __*init*/__*exit* annotations are already a constant source of bugs, 
> and adding more pifalls (e.g. forgotten removal of _i()/_e() when a 
> function is no longer __*init*/__*exit*) doesn't sound like a good plan.
> Shouldn't it be possible to automatically determine where to put the 
> strings? I don't know enough gcc/ld voodoo for being able to tell 
> whether it is currently possible, and if yes how, but doing it 
> automatically sounds like the only solution that wouldn't result in an
> unmaintainable mess.

gcc tends to place data such as strings or jump tables generated from
switches not into a place were it would be easily discardable.  The
latter is the reason that on MIPS we can't discard __exit functions
at all - a switch table in .rodata might be referencing discarded code
in .exit.text which makes ld fail.  When I discussed this with some gcc
people a while ago nobody really had a good suggestion to solve this.


<Prev in Thread] Current Thread [Next in Thread>