[U-Boot] [PATCH 2/8] dts/Makefile: simplify dtc invocation

[Stephen Warren <swarren@wwwdotorg.org>]

On 06/19/2013 02:37 PM, Simon Glass wrote:
> Hi Stephen,
> 
> On Mon, Jun 10, 2013 at 4:16 PM, Stephen Warren <swarren@wwwdotorg.org
> <mailto:swarren@wwwdotorg.org>> wrote:
...
>     Related, split the invocation of cpp and dtc into separate commands
>     rather than a pipeline, so that if either fail, it is detected. This has
>     the nice benefit of saving off the result of the pre-processing step,
>     allowing it to be easily inspected.
...
>     diff --git a/.gitignore b/.gitignore
...
>      $(DT_BIN): $(TOPDIR)/board/$(VENDOR)/dts/$(DEVICE_TREE).dts
...
>     +       $(CPP) -P $(DTS_CPPFLAGS) $< -o $(DT_BIN).dtstmp
>     +       $(DTC) -R 4 -p 0x1000 -O dtb -o ${DT_BIN} $(DT_BIN).dtstmp
> 
> 
> When you get an error here, will dtc report a bogus filename? Or will
> the CPP line information deal with that> - iwc please add a comment to
> the commit message.

Added this to commit description:

Assuming a new enough dtc (which an earlier patch enforces), dtc will
parse #line directives in its input file, and generate correct file and
line numbers in error messages, even though cpp is unconditionally
applied to its input file.

(note the patch that refers to will be new in v2 of the series).