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

On Mon, Sep 27 2021, Phillip Wood wrote:

Hi Ævar

On 27/09/2021 01:39, Ævar Arnfjörð Bjarmason wrote:

quoted

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 <redacted>
---
  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.

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.