Path: ...!eternal-september.org!feeder3.eternal-september.org!news.eternal-september.org!.POSTED!not-for-mail
From: Michael S <already5chosen@yahoo.com>
Newsgroups: comp.lang.c
Subject: Re: A Famous Security Bug
Date: Sun, 24 Mar 2024 17:26:41 +0300
Organization: A noiseless patient Spider
Lines: 59
Message-ID: <20240324172641.00005ede@yahoo.com>
References: <bug-20240320191736@ram.dialup.fu-berlin.de>
	<20240320114218.151@kylheku.com>
	<20240321211306.779b21d126e122556c34a346@gmail.moc>
	<utkea9$31sr2$1@dont-email.me>
	<utktul$35ng8$1@dont-email.me>
	<utm06k$3glqc$1@dont-email.me>
	<utme8b$3jtip$1@dont-email.me>
MIME-Version: 1.0
Content-Type: text/plain; charset=US-ASCII
Content-Transfer-Encoding: 7bit
Injection-Info: dont-email.me; posting-host="ea83786ed9d7b4303133f886081061ed";
	logging-data="443456"; mail-complaints-to="abuse@eternal-september.org";	posting-account="U2FsdGVkX1/SH9loVKg7wrcy8lU7ziHQlPjyMlq5BKU="
Cancel-Lock: sha1:s9BWYOyihGEyr+36mYl4065uvpE=
X-Newsreader: Claws Mail 3.19.1 (GTK+ 2.24.33; x86_64-w64-mingw32)
Bytes: 3040

On Sat, 23 Mar 2024 11:26:03 +0000
bart <bc@freeuk.com> wrote:

> On 23/03/2024 07:26, James Kuyper wrote:
> > bart <bc@freeuk.com> writes:  
> >> On 22/03/2024 17:14, James Kuyper wrote:  
> > [...]  
> >>> If you want to tell a system not only what a program must do, but
> >>> also how it must do it, you need to use a lower-level language
> >>> than C.  
> >>
> >> Which one?  
> > 
> > That's up to you. The point is, C is NOT that language.  
> 
> I'm asking which /mainstream/ HLL is lower level than C. So
> specifically ruling out assembly.
> 
> If there is no such choice, then this is the problem: it has to be C
> or nothing.
> 
> >> I don't think anyone seriously wants to switch to assembly for the
> >> sort of tasks they want to use C for.  
> > 
> > Why not? Assembly provides the kind of control you're looking for; C
> > does not. If that kind of control is important to you, you have to
> > find a language which provides it. If not assembler or C, what
> > would you use?  
> 
> Among non-mainstream ones, my own would fit the bill. Since I write
> the implementations, I can ensure the compiler doesn't have a mind of
> its own.
> 
> However if somebody else tried to implement it, then I can't
> guarantee the same behaviour. This would need to somehow be enforced
> with a precise language spec, or mine would need to be a reference 
> implementation with a lot of test cases.
> 
> 
> -----------------
> 
> Take this program:
> 
>    #include <stdio.h>
>    int main(void) {
>        goto L;
>        0x12345678;
>    L:
>        printf("Hello, World!\n");
>    }
> 
> If I use my compiler, then that 12345678 pattern gets compiled into
> the binary (because it is loaded into a register then discarded).
> That means I can use that value as a marker or sentinel which can be
> searched for.
>

Does it apply to your aarch64 compiler as well?