[OE-core] SDK meta-toolchain

[Kyle Farnsworth]

On 05/07/2013 11:36 AM, Mark Hatle wrote:
> On 5/7/13 11:09 AM, Kyle Farnsworth wrote:
>> I'm a bit confused about what exactly meta-toolchain is building?  It
>> seems to be bitbaking gcc and creating a toolchain with the prefix
>> x86_64-oesdk-linux- (default SDK_PREFIX) but I'm not sure what it is.
>> Is it a cross-compile for my target MACHINE or a compiler for my build
>> machine?  Based on the prefix name I am assuming the latter.
>
> There are two ways to generate an SDK.
>
> * targeted SDK -- This is a meta-toolchain* recipe that lists
> -exactly- what is going to be in the SDK.  This is great if you want
> to limit your SDK to specific libraries for your application developers.
>
> * implied / image based SDK -- This type of SDK bases off of what is
> in the image to generate an SDK that contains all of the libraries
> that are runnable inside of the image.  This is a very simple way to
> generate an SDK for application developers that -will- match the
> run-time image.
>
> Both of the above have their place, depending on the level of command
> and control people want.
>
> The basic meta-toolchain is just the cross compile toolchain and I
> believe the libc.  meta-toolchain-gmae is an example Gnome Mobile
> Application Environment.
Thanks. This a good info.  I need to do the targeted SDK.  But why is it
re-creating the cross-compile toolchain with the new prefix and a libc? 
I also have cases where I want to deliver an external toolchain within
the SDK.