On 15 August 2017 at 16:17, Torsten Bögershausen <[email protected]> wrote:
> On Tue, Aug 15, 2017 at 02:53:01PM +0200, Martin Ågren wrote:
>> convert_attrs populates a struct conv_attrs. The field attr_action is
>> not set in all code paths, but still one caller unconditionally reads
>> it. Since git_check_attr always returns the same value, we'll always end
>> up in the same code path and there is no problem right now. But
>> convert_attrs is obviously trying not to rely on such an
>> implementation-detail of another component.
>>
>> Initialize attr_action to CRLF_UNDEFINED in the dead code path.
>>
>> Actually, in the code path that /is/ taken, the variable is assigned to
>> twice and the first assignment has no effect. That's not wrong, but
>> let's remove that first assignment while we're here.
>>
>> Signed-off-by: Martin Ågren <[email protected]>
>> ---
>> I hit a warning about attr_action possibly being uninitialized when
>> building with SANITIZE=thread. I guess it's some random interaction
>> between code added by tsan, the optimizer (-O3) and the warning
>> machinery. (This was with gcc 5.4.0.)
>>
>> convert.c | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/convert.c b/convert.c
>> index 1012462e3..943d957b4 100644
>> --- a/convert.c
>> +++ b/convert.c
>> @@ -1040,7 +1040,6 @@ static void convert_attrs(struct conv_attrs *ca, const
>> char *path)
>> ca->crlf_action = git_path_check_crlf(ccheck + 4);
>> if (ca->crlf_action == CRLF_UNDEFINED)
>> ca->crlf_action = git_path_check_crlf(ccheck + 0);
>> - ca->attr_action = ca->crlf_action;
>
> I don't think the removal of that line is correct.
(Thanks for confirming in a follow-up mail that you meant that you /do/
think the removal is correct.)
>
>> ca->ident = git_path_check_ident(ccheck + 1);
>> ca->drv = git_path_check_convert(ccheck + 2);
>> if (ca->crlf_action != CRLF_BINARY) {
>> @@ -1058,6 +1057,7 @@ static void convert_attrs(struct conv_attrs *ca, const
>> char *path)
>> } else {
>> ca->drv = NULL;
>> ca->crlf_action = CRLF_UNDEFINED;
>> + ca->attr_action = CRLF_UNDEFINED;
>
> But this one can be avoided, when the line
> ca->attr_action = ca->crlf_action;
> would move completely out of the "if/else" block.
>
>> ca->ident = 0;
>> }
>> if (ca->crlf_action == CRLF_TEXT)
>> --
>> 2.14.1.151.gdfeca7a7e
>>
>
> Thanks for spotting my mess.
> What do you think about the following:
>
>
> diff --git a/convert.c b/convert.c
> index 1012462e3c..fd91b91ada 100644
> --- a/convert.c
> +++ b/convert.c
> @@ -1040,7 +1040,6 @@ static void convert_attrs(struct conv_attrs *ca, const
> char *path)
> ca->crlf_action = git_path_check_crlf(ccheck + 4);
> if (ca->crlf_action == CRLF_UNDEFINED)
> ca->crlf_action = git_path_check_crlf(ccheck + 0);
> - ca->attr_action = ca->crlf_action;
> ca->ident = git_path_check_ident(ccheck + 1);
> ca->drv = git_path_check_convert(ccheck + 2);
> if (ca->crlf_action != CRLF_BINARY) {
> @@ -1060,6 +1059,8 @@ static void convert_attrs(struct conv_attrs *ca, const
> char *path)
> ca->crlf_action = CRLF_UNDEFINED;
> ca->ident = 0;
> }
> + /* Save attr and make a decision for action */
> + ca->attr_action = ca->crlf_action;
> if (ca->crlf_action == CRLF_TEXT)
> ca->crlf_action = text_eol_is_crlf() ? CRLF_TEXT_CRLF :
> CRLF_TEXT_INPUT;
> if (ca->crlf_action == CRLF_UNDEFINED && auto_crlf == AUTO_CRLF_FALSE)
Yeah, makes lots of sense. Then we could also remove the second
assignment to attr_action. That is, this function would set attr_action
at one place, always. I'll do this in a v2.
Thanks.
