[OE-core] why 'FILESPATH =. "${FILE_DIRNAME}/u-boot-git/${MACHINE}:"' in u-boot.inc?

[Robert P. J. Day]

  a bit of an oddity as i'm playing with u-boot recipes in other
layers ... in a xilinx layer that sits above oe-core, i have the
u-boot recipe u-boot-zynq_git.bb (note, a full recipe, not a bbappend)
which opens with:

require recipes-bsp/u-boot/u-boot.inc

simplifying things, i removed the current FILESEXTRAPATHS_prepend from
that file (it has no effect on this question), then used bitbake-env
to see the final path for the "u-boot-zynq" recipe:

$ bitbake-env -r u-boot-zynq FILESPATH | tr ":" '\n'
# FILESPATH="${FILE_DIRNAME}/u-boot-git/${MACHINE}
${@base_set_filespath(["${FILE_DIRNAME}/${BP}",
"${FILE_DIRNAME}/${BPN}", "${FILE_DIRNAME}/files"], d)}"
FILESPATH="/home/rpjday/oe/dist/layers/xilinx/milo-zynq/recipes-bsp/u-boot/u-boot-git/zedboard
/home/rpjday/oe/dist/layers/xilinx/milo-zynq/recipes-bsp/u-boot/u-boot-zynq-xilinx-zynq/arm
/home/rpjday/oe/dist/layers/xilinx/milo-zynq/recipes-bsp/u-boot/u-boot-zynq-xilinx-zynq/armv7a
/home/rpjday/oe/dist/layers/xilinx/milo-zynq/recipes-bsp/u-boot/u-boot-zynq-xilinx-zynq/zedboard
/home/rpjday/oe/dist/layers/xilinx/milo-zynq/recipes-bsp/u-boot/u-boot-zynq-xilinx-zynq/
/home/rpjday/oe/dist/layers/xilinx/milo-zynq/recipes-bsp/u-boot/u-boot-zynq-xilinx-zynq/
/home/rpjday/oe/dist/layers/xilinx/milo-zynq/recipes-bsp/u-boot/u-boot-zynq/arm
/home/rpjday/oe/dist/layers/xilinx/milo-zynq/recipes-bsp/u-boot/u-boot-zynq/armv7a
/home/rpjday/oe/dist/layers/xilinx/milo-zynq/recipes-bsp/u-boot/u-boot-zynq/zedboard
/home/rpjday/oe/dist/layers/xilinx/milo-zynq/recipes-bsp/u-boot/u-boot-zynq/
/home/rpjday/oe/dist/layers/xilinx/milo-zynq/recipes-bsp/u-boot/u-boot-zynq/
/home/rpjday/oe/dist/layers/xilinx/milo-zynq/recipes-bsp/u-boot/files/arm
/home/rpjday/oe/dist/layers/xilinx/milo-zynq/recipes-bsp/u-boot/files/armv7a
/home/rpjday/oe/dist/layers/xilinx/milo-zynq/recipes-bsp/u-boot/files/zedboard
/home/rpjday/oe/dist/layers/xilinx/milo-zynq/recipes-bsp/u-boot/files/
/home/rpjday/oe/dist/layers/xilinx/milo-zynq/recipes-bsp/u-boot/files/"
$

  it's that first entry that's confusing to me:

FILESPATH="/home/rpjday/oe/dist/layers/xilinx/milo-zynq/recipes-bsp/u-boot/u-boot-git/zedboard

there is no such directory "u-boot-git" under that layer, but that
entry is clearly(?) being prepended by the processing of this line
from oe-core's u-boot.inc file:

FILESPATH =. "${FILE_DIRNAME}/u-boot-git/${MACHINE}:"

  but what is the point of that line in the oe-core layer? is that not
assuming that every conceivable u-boot recipe in every layer will
probably have that subdirectory? it seems kind of backwards for any
recipe or include file in oe-core to make any assumptions about the
structure of recipes or file subdirectories in "higher" layers. in
fact, i don't see a single "u-boot-git" recipe subdirectory anywhere
in any of the layers i have checked out.

  so what is that line doing? am i just confused? i'm aware it doesn't
do any damage, but it still looks weird.

rday

-- 

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Robert P. J. Day                                 Ottawa, Ontario, CANADA
                        http://crashcourse.ca

Twitter:                                       http://twitter.com/rpjday
LinkedIn:                               http://ca.linkedin.com/in/rpjday
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