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From: Keith Thompson <Keith.S.Thompson+u@gmail.com>
Newsgroups: comp.lang.c++
Subject: Re: I think references should have been const by default
Date: Tue, 26 Oct 2021 09:49:34 -0700
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Xref: csiph.com comp.lang.c++:82117

Bart <bc@freeuk.com> writes:
> On 26/10/2021 14:29, Ben Bacarisse wrote:
>> Bart <bc@freeuk.com> writes:
[...]
>>>     char* s = "ABC";
>> This relies on an a conversion that is valid (bad unwise) in C and
>> not
>> permitted in C++.
>
> I tried it in C++ before posting (as I'd thought that "ABC" would have
> type const char*) but it seemed to work. (Using -Wall -std=c++14.)

And you didn't bother to mention the diagnostic?  I get
    warning: ISO C++ forbids converting a string constant to ‘char*’ [-Wwrite-strings]
And of course with "-pedantic-errors" it becomes a fatal error.

Did you not get a diagnostic?  It's not all that interesting to see what
you can get away with by ignoring warnings.

> I'm writing about what is typically observed.

What I typically observe is that skilled programmers pay attention to
warnings and do not attempt to modify string literals.

> (I don't put string literals into a readonly segment because I haven't
> got round to it yet.
>
> It is surprising that a big compiler like MSVC doesn't do so either,
> but apparently that's only done when optimising; rather odd.)

My quick experiment with MSVC 2017 does not confirm that.
    char *s = "ABC";
gives a fatal error in C++.  It compiles in C (as expected), but
attempting to modify the literal causes a run-time crash.

-- 
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 */