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Re: [PATCH 5/5] cbtree.h: define cb_init() in terms of CBTREE_INIT

From
PWPhillip Wood <phillip.wood123@gmail.com>
Date
Sep 30, 2021, 10:01 UTC
Message-ID
<05770f9c-49e9-2572-d610-dcbd2b97cca3@gmail.com>
In-Reply-To
<87h7e61duk.fsf@evledraar.gmail.com>
On 27/09/2021 12:00, Ævar Arnfjörð Bjarmason wrote:
Show 40 quoted lines
> 
> On Mon, Sep 27 2021, Phillip Wood wrote:
> 
>> Hi Ævar
>>
>> On 27/09/2021 01:39, Ævar Arnfjörð Bjarmason wrote:
>>> Use the same pattern for cb_init() as the one established in the
>>> recent refactoring of other such patterns in
>>> 5726a6b4012 (*.c *_init(): define in terms of corresponding *_INIT
>>> macro, 2021-07-01).
>>> Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
>>> ---
>>>    cbtree.h | 5 +++--
>>>    1 file changed, 3 insertions(+), 2 deletions(-)
>>> diff --git a/cbtree.h b/cbtree.h
>>> index a04a312c3f5..dedbb8e2a45 100644
>>> --- a/cbtree.h
>>> +++ b/cbtree.h
>>> @@ -37,11 +37,12 @@ enum cb_next {
>>>    	CB_BREAK = 1
>>>    };
>>>    -#define CBTREE_INIT { .root = NULL }
>>> +#define CBTREE_INIT { 0 }
>>>      static inline void cb_init(struct cb_tree *t)
>>>    {
>>> -	t->root = NULL;
>>> +	struct cb_tree blank = CBTREE_INIT;
>>> +	memcpy(t, &blank, sizeof(*t));
>>>    }
>>
>> Slightly off topic but would this be a good site for a compound
>> literal test balloon?
>>
>> 	*t = (struct cb_tree){ 0 };
>>
>> Compound literals are in C99 and seem to have been supported by MSVC
>> since 2013 [1].
> 
> I think that's a good thing to test out, FWIW I've also tested it on the
> IBM xlc, Oracle SunCC and HP/UX's aCC, they all seem to accept it.

Thanks for taking the time to test those other systems, it's good to know they support compound literals

> But I'd prefer just doing that in some general follow-up to bd4232fac33
> (Merge branch 'ab/struct-init', 2021-07-16), i.e. let's just use the
> init pattern it established here.

I agree it makes sense to introduce it as a separate series. I'm not sure if there is a pressing need for them but it is the sort of thing that is occasionally useful.

Best Wishes
Phillip
Previous: Ævar Arnfjörð BjarmasonNext: Ævar Arnfjörð Bjarmason
Message 18 of 32 in “Designated initializer cleanup & conversion”
  1. 0/5 Designated initializer cleanup & conversionÆvar Arnfjörð Bjarmason, Sep 27, 2021
  2. 2/5 *.[ch] *_INIT macros: use { 0 } for a "zero out" idiomÆvar Arnfjörð Bjarmason, Sep 27, 2021
  3. Eric SunshineSep 27, 2021
  4. Johannes SixtSep 27, 2021
  5. Junio C HamanoSep 27, 2021
  6. 1/5 submodule-config.h: remove unused SUBMODULE_INIT macroÆvar Arnfjörð Bjarmason, Sep 27, 2021
  7. 3/5 *.h _INIT macros: don't specify fields equal to 0Ævar Arnfjörð Bjarmason, Sep 27, 2021
  8. 5/5 cbtree.h: define cb_init() in terms of CBTREE_INITÆvar Arnfjörð Bjarmason, Sep 27, 2021
  9. Johannes SixtSep 27, 2021
  10. Ævar Arnfjörð BjarmasonSep 27, 2021
  11. Jeff KingSep 27, 2021
  12. Johannes SixtSep 28, 2021
  13. Junio C HamanoSep 28, 2021
  14. Ævar Arnfjörð BjarmasonSep 28, 2021
  15. Junio C HamanoSep 28, 2021
  16. Phillip WoodSep 27, 2021
  17. Ævar Arnfjörð BjarmasonSep 27, 2021
  18. Phillip WoodSep 30, 2021
  19. 4/5 *.h: move some *_INIT to designated initializersÆvar Arnfjörð Bjarmason, Sep 27, 2021
  20. 0/5 Designated initializer cleanup & conversionÆvar Arnfjörð Bjarmason, Sep 27, 2021
  21. 1/5 submodule-config.h: remove unused SUBMODULE_INIT macroÆvar Arnfjörð Bjarmason, Sep 27, 2021
  22. Jeff KingSep 27, 2021
  23. 2/5 *.[ch] *_INIT macros: use { 0 } for a "zero out" idiomÆvar Arnfjörð Bjarmason, Sep 27, 2021
  24. Jeff KingSep 27, 2021
  25. Ævar Arnfjörð BjarmasonSep 28, 2021
  26. Jeff KingSep 28, 2021
  27. Ramsay JonesSep 28, 2021
  28. 3/5 *.h _INIT macros: don't specify fields equal to 0Ævar Arnfjörð Bjarmason, Sep 27, 2021
  29. Junio C HamanoSep 27, 2021
  30. 4/5 *.h: move some *_INIT to designated initializersÆvar Arnfjörð Bjarmason, Sep 27, 2021
  31. Junio C HamanoSep 27, 2021
  32. 5/5 cbtree.h: define cb_init() in terms of CBTREE_INITÆvar Arnfjörð Bjarmason, Sep 27, 2021

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