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From: Keith Thompson <Keith.S.Thompson+u@gmail.com>
Newsgroups: comp.lang.c
Subject: Re: C23 thoughts and opinions
Date: Sat, 25 May 2024 16:21:05 -0700
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David Brown <david.brown@hesbynett.no> writes:
> On 24/05/2024 21:29, Keith Thompson wrote:
[...]
>> "static_assert" is already a macro defined in <assert.h> starting in
>> C11.  The above code is valid in pre-C23, but will break in C11 and C17
>> if it includes <assert.h> directly or indirectly.  
>
> Yes.  But including <assert.h> is optional.

Your header that defines your own "static_assert" macro might depend on
some other header outside your control.  A future version of that other
header might add a "#include <assert.h>", breaking your code.

There are solutions (check "#ifdef static_assert" for the macro and
__STDC_VERSION__ for the keyword, etc.)

Perhaps it's not an issue for you, but it's a corner case to keep in
mind.

-- 
Keith Thompson (The_Other_Keith) Keith.S.Thompson+u@gmail.com
void Void(void) { Void(); } /* The recursive call of the void */