[U-Boot] [PATCH] kbuild: use -fmacro-prefix-map to make __FILE__ a relative path

[Simon Glass]

On 15 April 2018 at 22:18, Masahiro Yamada
<yamada.masahiro at socionext.com> wrote:
>
> The __FILE__ macro is used everywhere in U-Boot to locate the file
> printing the log message, such as WARN_ON(), etc.  If U-Boot is
> built out of tree, this can be a long absolute path.
>
> This is because Kbuild runs in the objtree instead of the srctree,
> then __FILE__ is expanded to a file path prefixed with $(srctree)/.
>
> A brand-new option from GCC, -fmacro-prefix-map, solves this problem.
> If your compiler supports it, __FILE__ is the relative path from the
> srctree regardless of O= option.  This provides more readable log,
> more reproducible builds, and smaller image size.
>
> [ Linux commit: a73619a845d5625079cc1b3b820f44c899618388 ]
>
> Signed-off-by: Masahiro Yamada <yamada.masahiro at socionext.com>
> ---
>
> GCC 8 is required to use this new option.
>
>
>  Makefile | 3 +++
>  1 file changed, 3 insertions(+)
>

Great!

Reviewed-by: Simon Glass <sjg at chromium.org>