Re: [issues] Building eglibc on systems with recent linux kernels

[Edmar Wienskoski-RA8797 <edmar@xxxxxxxxxxxxx>]

It seems I found the answer. I found that an even newer version of linux 
(2.6.22)
restores back the missing definitions.

Regarding --with-headers it was an oversight of my part. The build in 
the old
host happened with linux-2.6.22 after all. (The build with 2.6.19 
happened with
much older eglibc versions)

Thanks,
Edmar


Edmar Wienskoski-RA8797 wrote:
> I use to build eglibc with no problems, but recently the same build
> does not work anymore.
> Perhaps someone can tell me if this is a known problem or how to work 
> around it.
>
> Problem:
> The file sysdeps/unix/sysv/linux/ifaddrs.c gives me several undefined 
> symbols.
> One of them is IFLA_RTA
>
> Normally this symbol is defined in /usr/include/linux/rtnetlink.h
> But with newer versions of linux, IFLA_RTA does not exist anymore.
>
> I have being able to build eglibc with the following configuration 
> options
> --enable-kernel=2.6.19 --with-headers=<..>
> Note that linux 2.6.19 does not defines IFLA_RTA, but it happened that
> the machine I used to do the cross-build had a 2.6.9 kernel.
>
> Once the host was upgraded the build start failing.
>
> So,
> 1) The --enable-kernel option is used to checked against internal 
> minimum version,
> and assumes everything newer is ok. (i.e. it assumes that linux headers
> are always backwards compatible). Is this desirable ? Is this a known 
> problem ?
>
> 2) It seems that the system headers are used even though I specified 
> --with-headers=<..>
> I had the impression this option would prevent /usr/include to be used.
> I checked that --with-headers=<.../include/linux/rtnetlink.h> does 
> *not* have
> IFLA_RTA defined, but yet the build is successful in hosts with old 
> kernels...
> Am I misunderstanding these options ?
>
> Thanks
> Edmar