[OE-core] [PATCHv2 01/13] systemtap: remove usage of FILESPATH

[petter at technux.se]

2014-05-10 18:58 skrev Khem Raj:

> On Sat, May 10, 2014 at 1:05 AM, Petter Mabäcker <petter at technux.se>
> wrote:
>
>> +FILESEXTRAPATHS_prepend := "${THISDIR}/systemtap:"
>
> would something like
>
> FILESEXTRAPATHS =. "${FILE_DIRNAME}/systemtap:"
>
> avoid the prepend and immediate evaluation

I guess someone with deep bitbake knowledge can answer this better. But 
as far as I understand, you should always use immediate evaluation when 
using THISDIR, to be extra safe. Not sure if it's more safe to use 
FILE_DIRNAME if you want to avoid immediate expanding when using 
FILESEXTRAPATHS?

The bitbake documentations says:

"The operators "_append" and "_prepend" differ from the operators ".=" 
and "=." in that they are deferred until after parsing completes rather 
than being immediately applied."

Not sure if above means that "=." will also immediately expand 
variables or not?

Personally I have always used FILESEXTRAPATHS_prepend := 
"${THISDIR}/<somename>:" like the yocto documentation recommends. But 
sure if you can avoid immediate expanding in FILESEXTRPATHS, that would 
mean a tiny optimization. In that case perhaps the documentation should 
be updated as well. Looking in meta-layer both methods seems to be used.