Re: implicit pointer of pointer argument promotion legal C++?

Article View: comp.std.c++

Article #10

#10

From: mccauleyba
Date: Thu, 29 Oct 1992 19:55

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In article <23999@alice.att.com>, ark@alice.att.com (Andrew Koenig) writes:
> 
> Incidentally, I conjecture that conversion from T** to const T * const *
> (pointer to constant pointer to constant T) is always safe,
> but I don't have a proof.

There is another point that follows from all this when considering function
pointers. The current standard does not allow any promotion of function
pointers but can anyone say definitively if something like...

int strcmp(const char*,const char*);
int (*p)(char *,char*) = strcmp;

... could be safely allowed.

I can see no hazard in permitting conversion from (*)(const T*) to (*)(T*)
but then I hadn't seen the danger of converting T** to const T**.

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<1992Oct8.162653.12028@urbana.mcd.mot.com> <23842@alice.att.com> <23849@alice.att.com> <1992Oct15.222018.16565@urbana.mcd.mot.com> <23922@alice.att.com> <1992Oct22.212802.839@urbana.mcd.mot.com> <23999@alice.att.com>

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From: mccauleyba@vax1.bham.ac.uk
Newsgroups: comp.std.c++
Subject: Re: implicit pointer of pointer argument promotion legal C++?
Message-ID: <1992Oct29.195546.1@vax1.bham.ac.uk>
Date: 29 Oct 92 19:55:46 GMT
References: <1992Oct8.162653.12028@urbana.mcd.mot.com> <23842@alice.att.com> <23849@alice.att.com> <1992Oct15.222018.16565@urbana.mcd.mot.com> <23922@alice.att.com> <1992Oct22.212802.839@urbana.mcd.mot.com> <23999@alice.att.com>
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