I saw a DT build issue report some time before [1]. I was able to
reproduce the bug, and figure out the root cause.
Since commit 6d427c6b1fa0 ("binman: Automatically include a U-Boot
.dtsi file"), invalid .*.cmd files are generated.
Since that commit, DTS files are put into sed and piped to CPP.
Because CPP reads the stream from stdin, -Wp,-MD,$(depfile).pre.tmp
option generates a depfile with the target name "-". This is not
the format expected by fixdep.
Use one more temporary file instead of using pipe. With this, deps_
in the .*.cmd will be fixed. Having a temp file name in source_ is
odd, but it is unsed in the build system. Not a big deal.
[1] https://lists.denx.de/pipermail/u-boot/2017-June/294451.html
Fiexes: 6d427c6b1fa0 ("binman: Automatically include a U-Boot .dtsi file")
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
ecc9709fc1