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 Tue,  4 Feb 2020 20:13:42 +0300 (MSK)
Date: Tue, 4 Feb 2020 20:13:42 +0300
From: Nikita Pettik <korablev@tarantool.org>
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Subject: Re: [Tarantool-patches] [PATCH v3 1/2] b-tree: return NULL on
 matras_alloc fail
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To: Konstantin Osipov <kostja.osipov@gmail.com>, Ilya Kosarev <i.kosarev@tarantool.org>, tarantool-patches@dev.tarantool.org, v.shpilevoy@tarantool.org

On 31 Jan 11:18, Konstantin Osipov wrote:
> * Nikita Pettik <korablev@tarantool.org> [20/01/21 13:37]:
> > On 20 Jan 21:13, Ilya Kosarev wrote:
> > > In bps_tree_create_leaf we use matras_alloc in case
> > > bps_tree_garbage_pop didn't work out. However it also might not
> > > succeed. Then we need to return NULL instead of dereferencing NULL
> > > pointer.
> 
> I don't understand the attempt to fix it.
> 
> The reason the allocations are not checked - most likely -because
> BPS should refuse to even begin an operation if there is not
> enough memory in matras.

According to the code it doesn't look so. Matras allocation checked
on fails, except two ones in bps_tree_create_inner() and
bps_tree_create_leaf().
 
> Most likely Alexander Lyapunov was relying on that, and this is why you
> don't have these checks all over bps code.> 
> 
> -- 
> Konstantin Osipov, Moscow, Russia