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* [gentoo-user] Downgrading gcc
@ 2012-02-20  4:20 meino.cramer
  2012-02-20  4:30 ` [gentoo-user] " Nikos Chantziaras
                   ` (2 more replies)
  0 siblings, 3 replies; 5+ messages in thread
From: meino.cramer @ 2012-02-20  4:20 UTC (permalink / raw
  To: Gentoo

Hi,

I want to downgrade gcc from 4.5.3-r1 to 4.4.5.

The Gentoo gcc UPgrade guide tells me, that ABI are only upward
compatible which implies problems when downgrading and not upgrading.

Nonetheless a downgrade is needed here and I want to go 
to gcc-4.4.5.

How can I acchieve this in a clean way?

Best regards,
mcc









^ permalink raw reply	[flat|nested] 5+ messages in thread

* [gentoo-user] Re: Downgrading gcc
  2012-02-20  4:20 [gentoo-user] Downgrading gcc meino.cramer
@ 2012-02-20  4:30 ` Nikos Chantziaras
  2012-02-20  4:38 ` [gentoo-user] " Pandu Poluan
  2012-02-20 20:09 ` walt
  2 siblings, 0 replies; 5+ messages in thread
From: Nikos Chantziaras @ 2012-02-20  4:30 UTC (permalink / raw
  To: gentoo-user

On 20/02/12 06:20, meino.cramer@gmx.de wrote:
> Hi,
>
> I want to downgrade gcc from 4.5.3-r1 to 4.4.5.
>
> The Gentoo gcc UPgrade guide tells me, that ABI are only upward
> compatible which implies problems when downgrading and not upgrading.
>
> Nonetheless a downgrade is needed here and I want to go
> to gcc-4.4.5.
>
> How can I acchieve this in a clean way?

You don't need to downgrade.  You can just emerge it alongside 4.5.3 and 
switch to it with "gcc-config".  You can switch back and forth at will, 
meaning that you can build specific packages with 4.4.5 and keep the 
rest of the packages on 4.5.3.

Or if you really want everything built with 4.4.5, you can switch to it 
with "gcc-config" and then "emerge -e world".




^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: [gentoo-user] Downgrading gcc
  2012-02-20  4:20 [gentoo-user] Downgrading gcc meino.cramer
  2012-02-20  4:30 ` [gentoo-user] " Nikos Chantziaras
@ 2012-02-20  4:38 ` Pandu Poluan
  2012-02-20  5:02   ` [gentoo-user] " Nikos Chantziaras
  2012-02-20 20:09 ` walt
  2 siblings, 1 reply; 5+ messages in thread
From: Pandu Poluan @ 2012-02-20  4:38 UTC (permalink / raw
  To: gentoo-user

[-- Attachment #1: Type: text/plain, Size: 580 bytes --]

Just re-emerge the older version e.g. emerge =...gcc-4.4.5 (... is the
category). Then use eselect gcc or gcc-config to select the active gcc
version.

CMIIW

Rgds,
 On Feb 20, 2012 11:24 AM, <meino.cramer@gmx.de> wrote:

> Hi,
>
> I want to downgrade gcc from 4.5.3-r1 to 4.4.5.
>
> The Gentoo gcc UPgrade guide tells me, that ABI are only upward
> compatible which implies problems when downgrading and not upgrading.
>
> Nonetheless a downgrade is needed here and I want to go
> to gcc-4.4.5.
>
> How can I acchieve this in a clean way?
>
> Best regards,
> mcc
>
>
>
>
>
>
>
>

[-- Attachment #2: Type: text/html, Size: 872 bytes --]

^ permalink raw reply	[flat|nested] 5+ messages in thread

* [gentoo-user] Re: Downgrading gcc
  2012-02-20  4:38 ` [gentoo-user] " Pandu Poluan
@ 2012-02-20  5:02   ` Nikos Chantziaras
  0 siblings, 0 replies; 5+ messages in thread
From: Nikos Chantziaras @ 2012-02-20  5:02 UTC (permalink / raw
  To: gentoo-user

On 20/02/12 06:38, Pandu Poluan wrote:
> Just re-emerge the older version e.g. emerge =...gcc-4.4.5 (... is the
> category). Then use eselect gcc or gcc-config to select the active gcc
> version.

It's better to emerge it by using its slot:

   emerge gcc:4.4

so you can get updates normally for that slot.



>
> CMIIW
>
> Rgds,
>
> On Feb 20, 2012 11:24 AM, <meino.cramer@gmx.de
> <mailto:meino.cramer@gmx.de>> wrote:
>
>     Hi,
>
>     I want to downgrade gcc from 4.5.3-r1 to 4.4.5.
>
>     The Gentoo gcc UPgrade guide tells me, that ABI are only upward
>     compatible which implies problems when downgrading and not upgrading.
>
>     Nonetheless a downgrade is needed here and I want to go
>     to gcc-4.4.5.
>
>     How can I acchieve this in a clean way?
>
>     Best regards,
>     mcc
>
>
>
>
>
>
>





^ permalink raw reply	[flat|nested] 5+ messages in thread

* [gentoo-user] Re: Downgrading gcc
  2012-02-20  4:20 [gentoo-user] Downgrading gcc meino.cramer
  2012-02-20  4:30 ` [gentoo-user] " Nikos Chantziaras
  2012-02-20  4:38 ` [gentoo-user] " Pandu Poluan
@ 2012-02-20 20:09 ` walt
  2 siblings, 0 replies; 5+ messages in thread
From: walt @ 2012-02-20 20:09 UTC (permalink / raw
  To: gentoo-user

On 02/19/2012 08:20 PM, meino.cramer@gmx.de wrote:
> Hi,
> 
> I want to downgrade gcc from 4.5.3-r1 to 4.4.5.
> 
> The Gentoo gcc UPgrade guide tells me, that ABI are only upward
> compatible which implies problems when downgrading and not upgrading.
> 
> Nonetheless a downgrade is needed here and I want to go 
> to gcc-4.4.5.
> 

As the others have already said, gcc-config is the way to switch between
gcc versions.  In theory, every time you switch between different gcc's
you *should* run 'fix_libtool_files.sh <old-gcc-version-number>' *and*
recompile every package that links to libstdc++ (because libstdc++ is
part of the gcc package and gcc-config switches versions of libstdc++).

I suspect most people don't actually do those things, however :)
Just keep it in mind if any c++ applications start acting weird.





^ permalink raw reply	[flat|nested] 5+ messages in thread

end of thread, other threads:[~2012-02-20 20:11 UTC | newest]

Thread overview: 5+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2012-02-20  4:20 [gentoo-user] Downgrading gcc meino.cramer
2012-02-20  4:30 ` [gentoo-user] " Nikos Chantziaras
2012-02-20  4:38 ` [gentoo-user] " Pandu Poluan
2012-02-20  5:02   ` [gentoo-user] " Nikos Chantziaras
2012-02-20 20:09 ` walt

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