Re: [PATCH 34/34] checkpatch: Warn about usage of __DATE__, __TIME__ and __TIMESTAMP__

Michal Marek
2011-05-26T11:39:09Z

On 5.4.2011 16:59, Michal Marek wrote:
> The __TIME__ and __DATE__ macros are evil. Every C textbook mentions
> them, but forgets to add the tiny detail that they make sure that your
> code will never result in the same binary. __TIMESTAMP__ is a bit more
> sane, but again produces noise as soon as you switch branches back and
> forth, or apply a patch and revert it.
>
> Cc: Andy Whitcroft <apw@canonical.com>
> Signed-off-by: Michal Marek <mmarek@suse.cz>
> ---
> scripts/checkpatch.pl | 5 +++++
> 1 files changed, 5 insertions(+), 0 deletions(-)

Hi Andy,

any comments about this patch?

Thanks,
Michal

> diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
> index 4c0383d..dbcdf04 100755
> --- a/scripts/checkpatch.pl
> +++ b/scripts/checkpatch.pl
> @@ -2804,6 +2804,11 @@ sub process {
> WARN("__func__ should be used instead of gcc specific __FUNCTION__\n" . $herecurr);
> }
>
> +# check for pointless usage of __TIME__ and friends
> + if ($line =~ /\b__(TIME|DATE|TIMESTAMP)__\b/) {
> + WARN("Usage of __$1__ should be avoided to keep the build deterministic\n" . $herecurr);
> + }
> +
> # check for semaphores initialized locked
> if ($line =~ /^.\s*sema_init.+,\W?0\W?\)/) {
> WARN("consider using a completion\n" . $herecurr);