[U-Boot] [PATCH] scripts/check-config.sh: fix "command not found" error handling

[Simon Glass]

On 15 March 2018 at 04:08, Luca Ceresoli <luca at lucaceresoli.net> wrote:
> scripts/check-config.sh exits successfully and silently without doing
> any checks when the 'comm' command is not found.
>
> The problem triggers from the command around line 39:
>
>   comm -23 ${suspects} ${ok} >${new_adhoc}
>
> This statement fails when 'comm' is not in $PATH, creating an empty
> ${new_adhoc} file. But the script continues and the following line,
> which is supposed to detect an error:
>
>   if [ -s ${new_adhoc} ]; then
>
> will always be false since the file is empty, and the script will exit
> successfully as if everything were OK.
>
> The case where 'comm' in not in $PATH is not theoretical. It used to
> happen on yocto until a recent fix [0], and still happens on the
> current stable branch (rocko).
>
> Fix by setting the errexit flag to exit with error when a statement
> fails, so that at least the problem is noticed.
>
> For additional safety also set the nounset flag to detect expansion
> errors.
>
> [0] http://git.yoctoproject.org/cgit/cgit.cgi/poky/commit/?id=fe0b4cb5b48580d4a3f3c0eb82bfa6f1b13801e4
>
> Signed-off-by: Luca Ceresoli <luca at lucaceresoli.net>
> ---
>  scripts/check-config.sh | 3 +++
>  1 file changed, 3 insertions(+)

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

I wonder if we should have an explicit

|| die "msg"

at the end of the command that can fail, but this seems OK too.

Regards,
Simon