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

On Mon, Sep 27 2021, Johannes Sixt wrote:

Am 27.09.21 um 02:39 schrieb Ævar Arnfjörð Bjarmason:

quoted

--- 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;

This could be

	static const struct cb_tree blank = CBTREE_INIT;

*nod*...

quoted

+	memcpy(t, &blank, sizeof(*t));

Is
	*t = blank;

not a thing in C?

-- Hannes

...but to both this & the above my reply in the side-thread at
https://lore.kernel.org/git/87h7e61duk.fsf@evledraar.gmail.com/ (local)
applies. I.e. this is just following a pattern I got from Jeff King &
used in bd4232fac33 (Merge branch 'ab/struct-init', 2021-07-16).

FWIW with "const" in general I don't use it as much as I'd personally
prefer, see e.g. [1] for one recent discussion, but maybe there wouldn't
be any push-back in this case...

1. https://lore.kernel.org/git/patch-1.1-c317e6e125e-20210921T124416Z-avarab@gmail.com/ (local)