[gentoo-user] Re: how to "git-bisect" in a portage-compatible way ?

[walt <w41ter@gmail.com>]

On 03/10/2010 03:03 AM, Nicolas Richard wrote:
> Hello,
>
> ...
> So the general question is : if I want to use git-bisect (I have never
> done that before, but today is a good time to try),

It's a great tool and easy to use once you've learned the basic steps.
You can ask here if you need help with it.

> I guess it means
> I'll have to build libdrm outside portage : if so, once I'm finished
> with hunting the bug, how to go back to the situation where portage does
> everything for me ?

I can think of several possible ways, but here is one that "should"
work.

When you configure the git test package, use the "--prefix=/usr/local"
flag so that the test library gets installed in /usr/local/lib, and
/usr/local/include, etc.

Then, to test the new library, just change the /usr/lib/libdrm symlink
to point at /usr/local/lib/libdrm.so.whatever.

That avoids overwriting existing files, and you can just delete the files
in /usr/local when you finish.  Also, some packages have a "make uninstall"
option you could use instead.

Warning:  don't try this method with critical system libs like glibc.
Changing that symlink would break your whole system at warp speed.