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Date: Fri, 24 Feb 2023 00:56:02 +0000
From: Joseph Myers <joseph@codesourcery.com>
To: Qing Zhao <qing.zhao@oracle.com>
CC: Richard Biener <rguenther@suse.de>, Siddhesh Poyarekar
	<siddhesh@gotplt.org>, Kees Cook <keescook@chromium.org>, Gcc Patches
	<gcc-patches@gcc.gnu.org>
Subject: Re: [v3][PATCH 2/2] Update documentation to clarify a GCC extension
 (PR77650)
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Message-ID: <d627a9-3fd3-8032-114b-341d5d72cab3@codesourcery.com>
References: <20230211005013.789161-3-qing.zhao@oracle.com> <89D4C326-54FD-4403-8E54-6CE5B21AA411@oracle.com> <68c735b-90cc-14ef-be83-db1b754ad0f4@codesourcery.com> <EFA5315F-CBA1-425B-B2B5-874C0333A965@oracle.com>
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On Thu, 23 Feb 2023, Qing Zhao via Gcc-patches wrote:

> But the following:
> 
> struct flex1  { int length1; char data1[]; };
> struct flex2  { int length2; char data2[]; };
> union union_flex { struct flex1 f1; struct flex2 f2; };  /* this is C standard.  */
> 
> struct out_flex { int n; union union_flex flex_data1;};  /* this is GNU extension.  */
> 
> Should add this item into the documentation?

"union that contains a structure with a flexible array member" is just 
like "structure with a flexible array member".  I suppose the 
documentation should try to make that clear, without repeating it too much 
for every separate case.

-- 
Joseph S. Myers
joseph@codesourcery.com