Re: [gentoo-user] Questions on Raspberry Pi cross compiling

[R0b0t1]

On Thu, Jul 20, 2017 at 1:20 AM, Danny YUE <sheepduke@×××××.com> wrote:
>
> On 2017-07-20 05:59, R0b0t1 <r030t1@×××××.com> wrote:
>> On Thu, Jul 20, 2017 at 12:42 AM, Danny YUE <sheepduke@×××××.com> wrote:
>>> Hi guys,
>>>
>>> I am setting up cross compiling environment for my newly bought
>>> Raspberry Pi 3, under the guide of:
>>> https://wiki.gentoo.org/wiki/Raspberry_Pi
>>> https://wiki.gentoo.org/wiki/Raspberry_Pi/Quick_Install_Guide
>>>
>>> My original idea was to use crossdev to cross compile packages on my PC
>>> and install binaries on RPI.
>>> However I found it really nasty because it kept giving me the error
>>> message about "libintl: no such file or directory" during compilation of
>>> packages such as attr, python etc.
>>>
>>> And if some (even very few) packages fail to build on the PC, it is
>>> hardly possible to keep PC and RPI 'consistent'.
>>> (Yes, I did setup the 'make.profile' symlink to the right place.)
>>>
>>> So my question is:
>>> 1) If some packages are *doomed* to fail, how do you keep the
>>> emerge world environment consistency between PC and RPI?
>>> Or is my understanding of this method incorrect?
>>>
>>
>> Match compilation and USE flags.
>>
>>> 2) If it is not really a good idea to use crossdev, which one do you
>>> recommend between distcc and chroot method?
>>> (I googled but did not really get one answer about compilation speed.)
>>>
>>
>> You should be able to mix crossdev compiled packages freely with
>> device compiled ones. Incompatible packages will be ignored and it
>> will try to recompile a package with matching flags, so pay attention.
>> If you need to compile something on device then I suspect you want to
>> use distcc if at all possible.
>>
> Thanks for your reply. :-)
>
> Well, yes. But do you know how is distcc compared with chroot referring
> to compilation speed?
>

Using qemu-user to emulate the target architecture and hosting the
system in a chroot is generally slower than compiling on device, if
that is what you are referring to. I've read of people who tested this
with the RPi3 and some Hardkernel devices.