Re: [Ltib] libraries in toolchain and rootfs

[Stuart Hughes]

Hi Henry,

I guess this is a new toolchain you have put into LTIB?
Which platform are you building for?
Which LTIB are you using?

To answer your questions:

1. What do you mean by the library is downloaded? LTIB does not
automatically download libraries for you.  You should not have to add
any -I to the build.  DirectFB needs kernel headers, which it should be
getting from $DEV_IMAGE/usr/src/linux/include

2. Again what do you mean by library?  The toolchain is independent of
the rootfs, however here are some ideas:

rootfs/lib, rootfs/usr/lib will include libc/libstdc++ copied out of the
current toolchain.

additional packages that you build will add their own interface
libraries to rootfs/usr/lib (and other places), these have nothing to do
with the cross compiler (toolchain).

NOTE: the openembedded toolchain may not be suitable for use for LTIB.
You need to check that the right components got copied without errors
when building base_libs.  This is what copied the headers/libraries from
the toolchain to rootfs/....

Please include some output that shows the errors you are seeing
otherwise it's almost impossible to guess what is actually causing your
problems.

Regards, Stuart


hong zhang wrote:
> Stuart,
> 
> I am using openembedded toolchain to try build directfb application.
> Here is questions.
> 
> 1. If a compile error complains "not find a library", then library is 
> downloaded, built and installed to rootfs. That means compiler looks into 
> rootfs. Why need -I ../toolchain/include/directfb?
> 
> 2. Does toolchain has same library as rootfs? Or where does toolchain refer 
> to?
> 
> ---henry 
> 
> --- On Wed, 5/12/10, Stuart Hughes <address@hidden> wrote:
> 
>> From: Stuart Hughes <address@hidden>
>> Subject: Re: [Ltib] libraries in toolchain and rootfs
>> To: "hong zhang" <address@hidden>
>> Cc: address@hidden
>> Date: Wednesday, May 12, 2010, 2:35 AM
>> Hi HEnry,
>>
>> Which platform/toolchain/package are you referring to?
>>
>> Although you may have fixed a compile issue by adding this
>> path, it
>> isn't necessarily correct.  Also it's not normally
>> necessary to refer to
>> rootfs/.., for userspace apps, pkg-config is used for
>> headers not in
>> rootfs/usr/include (which itself is implicit).
>>
>> It's possible the headers you pick up through toolchain/..
>> are from the
>> build-in generic kernel header copies that come with all
>> toolchains but
>> it's not possible to tell without more detail.
>>
>> Regards, Stuart
>>
>> hong zhang wrote:
>>> Stuart,
>>>
>>> I have a technical question regarding libraries in
>> toolchain and rootfs.
>>>   
>>> When I cross compile user application, I have to add
>> -I .../toolchain/include/directfb instead -I
>> ../rootfs/include/directfb in Makefile. Does it mean
>> toolchain also has libraries as rootfs has?
>>> ---henry
>>>
>>>
> 
> 
>       
>