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NNTP-Posting-Date: Wed, 20 Jul 2016 14:38:11 -0500
From: Gareth Owen <gwowen@gmail.com>
Newsgroups: comp.lang.c
Subject: Re: A glitch regarding the usual malloc() idiom
References: <lnr3apmfbl.fsf@kst-u.example.com> <nmmu85$c1p$1@dont-email.me> <nmn0uu$i8g$1@dont-email.me> <4cd22745-22ad-4ac7-bdba-39ffa1c75e13@googlegroups.com> <lna8hcmgux.fsf@kst-u.example.com> <7d995799-5f23-4784-a62e-ea423de00650@googlegroups.com> <nmoj6s$lm4$1@dont-email.me>
Date: Wed, 20 Jul 2016 20:38:11 +0100
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Xref: csiph.com comp.lang.c:90687

Richard Heathfield <rjh@cpax.org.uk> writes:

>> It's the double abstraction problem
>>
>> magptr = malloc(40 * sizeof(float));
>>
>> tells us that we are asking for 160 bytes of memory.
>
> No, it doesn't. It tells us we're asking for 40 * sizeof(float) bytes
> of memory.

Supremely confident idiot.