[OE-core] RFC: Maintain backwards compatibility or not for module-base.bbclass

[Koen Kooi]

Op 16 jan. 2014, om 14:58 heeft Peter Kjellerstedt <peter.kjellerstedt at axis.com> het volgende geschreven:

> Background: Back in September, Richard made a commit to 
> linux-libc-headers.inc describing why one should not fork the 
> linux-libc-headers recipe:
> 
> http://git.yoctoproject.org/cgit/cgit.cgi/poky/commit/?id=babbf7a46acaefd9b36031483cafce053f607e66
> 
> As a result I created a local bbclass for our layer called 
> kernel-headers, which provides a recipe with kernel headers 
> that match the actually used version of the Linux kernel.
> This was needed for packages that need to access hardware 
> specific features that are not present in the generic kernel 
> headers provided by linux-libc-headers.
> 
> My intention for this class was that it should be generic 
> enough to be able to upstream it to OE Core.
> 
> Now, the other day a colleague of mine had a build failure due 
> to this class. It turned out that even though the class adds a 
> dependency on virtual/kernel and then uses the files that are 
> installed to ${STAGING_KERNEL_DIR} when running oe_runmake 
> headers_install, the command could fail because the 
> ${STAGING_KERNEL_DIR}/scripts was not populated. After asking 
> Richard about this, I learned that this is due to problems 
> with the sstate cache and not knowing whether a 32 bit host or 
> a 64 bit host was used to generate the files. Thus I also 
> learned that the scripts are actually built as a result of 
> building modules.
> 
> Since I did not want my class to depend on modules having been 
> built, I looked into modules.bbclass and modules-base.bbclass. 
> There I found the function do_make_scripts() which is 
> responsible for building  the kernel scripts. However, the 
> current setup doesn't lend itself very well to use the 
> modules-base.bbclass for something other than modules.
> 
> My idea then was to break this part out into a separate class, 
> kernel-scripts, which I did. You can find both the 
> kernel-scripts and kernel-headers classes here: 
> 
> http://git.yoctoproject.org/cgit/cgit.cgi/poky-contrib/log/?h=pkj/kernel-headers
> 
> When I showed this to Richard he noted that my change was not 
> backwards compatible (as I no longer provide the 
> do_make_scripts() function from the module-base.bbclass). 
> However, there is nothing besides module.bbclass in OE Core 
> and meta-oe that use the module-base.bbclass.

Can't do_make_script run as an sstate post function? 

regards,

Koen