From: Ian Lance Taylor <iant@google.com>
To: Eli Bendersky <eliben@gmail.com>
Cc: gcc-help@gnu.org
Subject: Re: why does -fno-pic coge generation on x64 require the large model?
Date: Mon, 07 Nov 2011 15:37:00 -0000 [thread overview]
Message-ID: <mcrpqh46j13.fsf@dhcp-172-18-216-180.mtv.corp.google.com> (raw)
In-Reply-To: <CAF-Rda_zw1y5KHk4rYD9hBdSYq8aeSUawXfZDk=YhKfTFLJR=A@mail.gmail.com> (Eli Bendersky's message of "Mon, 7 Nov 2011 13:39:05 +0200")
Eli Bendersky <eliben@gmail.com> writes:
> I'm experimenting with generating PIC and non-PIC code on x64 Ubuntu.
> It's possible to generate non PIC code as follows:
>
> gcc -fno-PIC -mcmodel=large -shared -c file.c
>
> However, I noticed that for other models (i.e. -mcmodel=small, or by
> default, without the -mcmodel argument), the code being generated is
> not really suitable for PIC as it has problematic load-time
> relocations.
>
> My question is - why is the large model required to generate true PIC code?
It's odd to try to create PIC while using -fno-PIC. I think you must
have some goal in mind for what you want your generated code to look
like, but I don't know what that is. It most likely does not correspond
to gcc's goal when using -fno-PIC, which is to not generate PIC.
Ian
next prev parent reply other threads:[~2011-11-07 15:37 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-11-07 11:39 Eli Bendersky
2011-11-07 15:37 ` Ian Lance Taylor [this message]
2011-11-07 15:57 ` Eli Bendersky
2011-11-07 17:17 ` Andrew Haley
2011-11-07 18:12 ` Ian Lance Taylor
2011-11-08 3:19 ` Eli Bendersky
2011-11-08 5:49 ` Ian Lance Taylor
2011-11-08 6:09 ` Eli Bendersky
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