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From: Keith Thompson <Keith.S.Thompson+u@gmail.com>
Newsgroups: comp.lang.c,comp.lang.c++
Subject: Re: Compile time checking of standards conformance
Date: Thu, 23 May 2024 15:32:06 -0700
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Paavo Helde <eesnimi@osa.pri.ee> writes:
> On 23.05.2024 02:44, olcott wrote:
>> Does enables conformance mean: Flags non conformance?
>
> No. Enabling conformance means enabling support for the conforming features.
>
> Flagging non-conformance is not possible in general as there are more
> creative fools out there than there are compiler writers.
>
> There are zillions of ways to write non-conforming code, for example
> an endless loop is not conforming in C++. The compiler is not obliged
> to diagnose it, but it is allowed for the compiler to silently
> optimize the non-conforming code away, assuming it is never called. At
> least that's what g++ folks think.

A conforming C compiler must produce a diagnostic for any violation of
any syntax rule or constraint.  Many C constructs (for example signed
integer overflow) have *undefined behavior*, which need not be
diagnosed.

C++ has similar rules.

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