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From: Keith Thompson <Keith.S.Thompson+u@gmail.com>
Newsgroups: comp.lang.c
Subject: Re: Padding between char array/VLA in struct?
Date: Mon, 02 Aug 2021 11:12:39 -0700
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Ian Pilcher <arequipeno@gmail.com> writes:
> Given the following:
>
>   struct foo {
>       /* other members */
>       char prefix[PREFIX_SIZE];
>       char name[];
>   };
>
> Is there any circumstance in which the compiler is permitted to insert
> padding between the 'prefix' and 'name' members?
>
> I'm 99% sure than the answer is no, but I've been unable to track down
> the actual rules anywhere.

I'm 99% sure the answer is "always".

Compilers typically insert padding only when it's necessary to meet
alignment requirements, but compilers are allowed to insert arbitrary
padding between members.

-- 
Keith Thompson (The_Other_Keith) Keith.S.Thompson+u@gmail.com
Working, but not speaking, for Philips
void Void(void) { Void(); } /* The recursive call of the void */