struct my_struct *p = (struct my_struct *)malloc(sizeof(struct my_struct));

[Chris Fogelklou]

What is wrong with the above?

Don't worry, I already know (learned my lesson last week.) It is for the
benefit of our resident compiler guru who seems to think you need the cast.
I thought it too, up until I started posting here!

Thanks,

Chris

[Chris Fogelklou]

Re: struct my_struct *p = (struct my_struct *)malloc(sizeof (struct my_struct));

"Chris Fogelklou" <chris.fogelklo u@comhem.se> wrote in message
news:7lxfc.8975 8$dP1.269223@ne wsc.telia.net.. .[color=blue]
> What is wrong with the above?
>
> Don't worry, I already know (learned my lesson last week.) It is for the
> benefit of our resident compiler guru who seems to think you need the[/color]
cast.[color=blue]
> I thought it too, up until I started posting here!
>
> Thanks,
>
> Chris
>[/color]
Even better, here is the email itself. Please help!

<start email>
First, Casts from void * are necessary both in C and C++. This is from the
same reason you told me: otherwise, if the compiler wouldn't
know what is the size of the object which is pointed at, it might get
confused with arithmetic operations. You can ask him where did he learned
this rule from. tell me if you want me to correspond directly with him.

Second, a possible reason to use integral types for addresses rather than
void *, is that in order to perform bitwise operations on an
address, you have to use operators of an integral type.
<end email>

[Régis Troadec]

Re: struct my_struct *p = (struct my_struct *)malloc(sizeof (struct my_struct));


"Chris Fogelklou" <chris.fogelklo u@comhem.se> a écrit dans le message de
news:Snxfc.8975 9$dP1.269223@ne wsc.telia.net.. .[color=blue]
> "Chris Fogelklou" <chris.fogelklo u@comhem.se> wrote in message[/color]

Hi,
[color=blue]
> news:7lxfc.8975 8$dP1.269223@ne wsc.telia.net.. .[color=green]
> > What is wrong with the above?
> >
> > Don't worry, I already know (learned my lesson last week.) It is for[/color][/color]
the[color=blue][color=green]
> > benefit of our resident compiler guru who seems to think you need the[/color]
> cast.[color=green]
> > I thought it too, up until I started posting here!
> >
> > Thanks,
> >
> > Chris
> >[/color]
> Even better, here is the email itself. Please help!
>
> <start email>
> First, Casts from void * are necessary both in C and C++. This is from the[/color]

Casts from void* are necessary in C++, not in C.
[color=blue]
> same reason you told me: otherwise, if the compiler wouldn't
> know what is the size of the object which is pointed at, it might get
> confused with arithmetic operations. You can ask him where did he learned
> this rule from. tell me if you want me to correspond directly with him.
>
> Second, a possible reason to use integral types for addresses rather than
> void *, is that in order to perform bitwise operations on an
> address, you have to use operators of an integral type.
> <end email>
>[/color]

Regis

[Chris Fogelklou]

Re: struct my_struct *p = (struct my_struct *)malloc(sizeof (struct my_struct));


"Régis Troadec" <regt@wanadoo.f r> wrote in message
news:c5m8hk$hc5 $1@news-reader3.wanadoo .fr...[color=blue]
>
> "Chris Fogelklou" <chris.fogelklo u@comhem.se> a écrit dans le message de
> news:Snxfc.8975 9$dP1.269223@ne wsc.telia.net.. .[color=green]
> > "Chris Fogelklou" <chris.fogelklo u@comhem.se> wrote in message[/color]
>
> Hi,
>[color=green]
> > news:7lxfc.8975 8$dP1.269223@ne wsc.telia.net.. .[color=darkred]
> > > What is wrong with the above?
> > >
> > > Don't worry, I already know (learned my lesson last week.) It is for[/color][/color]
> the[color=green][color=darkred]
> > > benefit of our resident compiler guru who seems to think you need the[/color]
> > cast.[color=darkred]
> > > I thought it too, up until I started posting here!
> > >
> > > Thanks,
> > >
> > > Chris
> > >[/color]
> > Even better, here is the email itself. Please help!
> >
> > <start email>
> > First, Casts from void * are necessary both in C and C++. This is from[/color][/color]
the[color=blue]
>
> Casts from void* are necessary in C++, not in C.[/color]

I am aware... I'm fishing for more info! Perhaps if I reposted again and
said you were wrong I'll get more...

You're WRONG!
[color=blue]
>[color=green]
> > same reason you told me: otherwise, if the compiler wouldn't
> > know what is the size of the object which is pointed at, it might get
> > confused with arithmetic operations. You can ask him where did he[/color][/color]
learned[color=blue][color=green]
> > this rule from. tell me if you want me to correspond directly with him.
> >
> > Second, a possible reason to use integral types for addresses rather[/color][/color]
than[color=blue][color=green]
> > void *, is that in order to perform bitwise operations on an
> > address, you have to use operators of an integral type.
> > <end email>
> >[/color]
>
> Regis
>
>[/color]

[Thomas Stegen]

Re: struct my_struct *p = (struct my_struct *)malloc(sizeof (structmy_struc t));

Chris Fogelklou wrote:
[color=blue]
> Even better, here is the email itself. Please help!
>
> <start email>
> First, Casts from void * are necessary both in C and C++. This is from the
> same reason you told me: otherwise, if the compiler wouldn't
> know what is the size of the object which is pointed at, it might get
> confused with arithmetic operations. You can ask him where did he learned
> this rule from. tell me if you want me to correspond directly with him.[/color]

Yes, please tell her to come here. On the other hand, don't, tell
her to read the archives. This conversation is getting old ;)

the ISO/IEC 9899:1999 standard section 6.3.2.3 has what you want. That
is C99 btw. Don't know the clause in C89.
[color=blue]
>
> Second, a possible reason to use integral types for addresses rather than
> void *, is that in order to perform bitwise operations on an
> address, you have to use operators of an integral type.[/color]

This much is true. But it is in implementation defined behaviour land,
most compilers behave very nicely when it comes to this though.

--
Thomas.

[Thomas Stegen]

Re: struct my_struct *p = (struct my_struct *)malloc(sizeof (structmy_struc t));

Chris Fogelklou wrote:
[color=blue]
> What is wrong with the above?
>
> Don't worry, I already know (learned my lesson last week.) It is for the
> benefit of our resident compiler guru who seems to think you need the cast.
> I thought it too, up until I started posting here!
>[/color]

struct my_struct *p = (struct my_struct *)malloc(sizeof (struct
my_struct));

There is nothing wrong with the above. It is considered a better
idiom to use

struct my_struct *p = malloc(sizeof *p);

The argument that the compiler does not know the type of the object
is bogus since all the information is already there. The compiler knows
the type of p, it knows the type of the value returned by malloc,
nothing is missing.

In my previous reply I mentioned 6.3.2.3, I should also have mentioned
clause 6.5.4 and 6.5.16.1 which is where the "no cast required" part is.

--
Thomas.

[Régis Troadec]

Re: struct my_struct *p = (struct my_struct *)malloc(sizeof (struct my_struct));


"Chris Fogelklou" <chris.fogelklo u@comhem.se> a écrit dans le message de
news:3Hxfc.8976 2$dP1.269154@ne wsc.telia.net.. .

Yes, sorry for that, i read your post too quickly,
[color=blue]
> "Régis Troadec" <regt@wanadoo.f r> wrote in message
> news:c5m8hk$hc5 $1@news-reader3.wanadoo .fr...[color=green]
> >
> > "Chris Fogelklou" <chris.fogelklo u@comhem.se> a écrit dans le message de
> > news:Snxfc.8975 9$dP1.269223@ne wsc.telia.net.. .[color=darkred]
> > > "Chris Fogelklou" <chris.fogelklo u@comhem.se> wrote in message[/color]
> >
> > Hi,
> >[color=darkred]
> > > news:7lxfc.8975 8$dP1.269223@ne wsc.telia.net.. .
> > > > What is wrong with the above?
> > > >
> > > > Don't worry, I already know (learned my lesson last week.) It is[/color][/color][/color]
for[color=blue][color=green]
> > the[color=darkred]
> > > > benefit of our resident compiler guru who seems to think you need[/color][/color][/color]
the[color=blue][color=green][color=darkred]
> > > cast.
> > > > I thought it too, up until I started posting here!
> > > >
> > > > Thanks,
> > > >
> > > > Chris
> > > >
> > > Even better, here is the email itself. Please help!
> > >
> > > <start email>
> > > First, Casts from void * are necessary both in C and C++. This is from[/color][/color]
> the[color=green]
> >
> > Casts from void* are necessary in C++, not in C.[/color]
>
> I am aware... I'm fishing for more info! Perhaps if I reposted again and
> said you were wrong I'll get more...
>
> You're WRONG![/color]

void* is implicitly converted to the destination pointer type (C99 §6.3.2.3
and §7.20.3.1).
[color=blue][color=green]
> >[color=darkred]
> > > same reason you told me: otherwise, if the compiler wouldn't
> > > know what is the size of the object which is pointed at, it might get
> > > confused with arithmetic operations.[/color][/color][/color]

sizeof ?
[color=blue]
>You can ask him where did he
> learned[color=green][color=darkred]
> > > this rule from. tell me if you want me to correspond directly with[/color][/color][/color]
him.[color=blue][color=green][color=darkred]
> > >
> > > Second, a possible reason to use integral types for addresses rather[/color][/color]
> than[color=green][color=darkred]
> > > void *, is that in order to perform bitwise operations on an
> > > address, you have to use operators of an integral type.[/color][/color][/color]

It's also said in the standard (C99), part 6 of §6.3.2.3 that :
"Any pointer type may be converted to an integer type. Except as previously
specified, the result is implementation-defined. If the result cannot be
represented in the integer type, the behavior is undefined. The result need
not be in the range of values of any integer type."

Is he/she sure that he/she can always hold his adressses with an integral
type ? It implies sizeof(the famous integral type) >= sizeof(void*).

There is a way in C99 to hold pointers and adresses with integers thanks to
the types intptr_t and uintptr_t. (C99 7.18.1.4), but I'm not sure it's
possible in C90..

Regis
[color=blue][color=green][color=darkred]
> > > <end email>
> > >[/color]
> >
> > Regis
> >
> >[/color]
>[/color]

[Chris Fogelklou]

Re: struct my_struct *p = (struct my_struct *)malloc(sizeof (struct my_struct));

"Thomas Stegen" <tstegen@cis.st rath.ac.uk> wrote in message
news:c5m9qn$3c0 d0$1@ID-228872.news.uni-berlin.de...[color=blue]
> Chris Fogelklou wrote:
>[color=green]
> > What is wrong with the above?
> >
> > Don't worry, I already know (learned my lesson last week.) It is for[/color][/color]
the[color=blue][color=green]
> > benefit of our resident compiler guru who seems to think you need the[/color][/color]
cast.[color=blue][color=green]
> > I thought it too, up until I started posting here!
> >[/color]
>
> struct my_struct *p = (struct my_struct *)malloc(sizeof (struct
> my_struct));
>
> There is nothing wrong with the above. It is considered a better
> idiom to use
>
> struct my_struct *p = malloc(sizeof *p);
>
> The argument that the compiler does not know the type of the object
> is bogus since all the information is already there. The compiler knows
> the type of p, it knows the type of the value returned by malloc,
> nothing is missing.
>
> In my previous reply I mentioned 6.3.2.3, I should also have mentioned
> clause 6.5.4 and 6.5.16.1 which is where the "no cast required" part is.
>
> --
> Thomas.
>[/color]

Hi Thomas,

Thanks! OK, then what about this:

int my_func(void *pinst)
{
my_struct *pthis = (my_struct *)pinst; //Cast
pthis->print("Lets see what's wrong with this!");
return 0;
}

If it is OK to never cast to/from void * as was made abundantly clear last
week, then this is also OK. However, pinst could be a run-time defineable
value.

Thanks!

Chris

[CBFalconer]

Re: struct my_struct *p = (struct my_struct *)malloc(sizeof (structmy_struc t));

Chris Fogelklou wrote:[color=blue]
> "Chris Fogelklou" <chris.fogelklo u@comhem.se> wrote in message
>[color=green]
> > What is wrong with the above?
> >
> > Don't worry, I already know (learned my lesson last week.) It
> > is for the benefit of our resident compiler guru who seems to
> > think you need the cast. I thought it too, up until I started
> > posting here!
> >[/color]
> Even better, here is the email itself. Please help!
>
> <start email>
> First, Casts from void * are necessary both in C and C++. This is
> from the same reason you told me: otherwise, if the compiler
> wouldn't know what is the size of the object which is pointed at,
> it might get confused with arithmetic operations. You can ask him
> where did he learned this rule from. tell me if you want me to
> correspond directly with him.
>
> Second, a possible reason to use integral types for addresses
> rather than void *, is that in order to perform bitwise operations
> on an address, you have to use operators of an integral type.
> <end email>[/color]

Don't get too antsy with him/her. This sounds like some system
programming operations on some embedded system, where the rules
are often different. The cast of the malloc remains unnecessary
(and don't put the question in the subject only).

Do learn to organize your questions into a single consistent
message, rather than a bit here and a bit there.

--
fix (vb.): 1. to paper over, obscure, hide from public view; 2.
to work around, in a way that produces unintended consequences
that are worse than the original problem. Usage: "Windows ME
fixes many of the shortcomings of Windows 98 SE". - Hutchison

[Chris Fogelklou]

Re: struct my_struct *p = (struct my_struct *)malloc(sizeof (struct my_struct));

"Régis Troadec" <regt@wanadoo.f r> wrote in message
news:c5maek$b90 $1@news-reader4.wanadoo .fr...[color=blue]
>
> "Chris Fogelklou" <chris.fogelklo u@comhem.se> a écrit dans le message de
> news:3Hxfc.8976 2$dP1.269154@ne wsc.telia.net.. .
>
> Yes, sorry for that, i read your post too quickly,
>[color=green]
> > "Régis Troadec" <regt@wanadoo.f r> wrote in message
> > news:c5m8hk$hc5 $1@news-reader3.wanadoo .fr...[color=darkred]
> > >
> > > "Chris Fogelklou" <chris.fogelklo u@comhem.se> a écrit dans le message[/color][/color][/color]
de[color=blue][color=green][color=darkred]
> > > news:Snxfc.8975 9$dP1.269223@ne wsc.telia.net.. .
> > > > "Chris Fogelklou" <chris.fogelklo u@comhem.se> wrote in message
> > >
> > > Hi,
> > >
> > > > news:7lxfc.8975 8$dP1.269223@ne wsc.telia.net.. .
> > > > > What is wrong with the above?
> > > > >
> > > > > Don't worry, I already know (learned my lesson last week.) It is[/color][/color]
> for[color=green][color=darkred]
> > > the
> > > > > benefit of our resident compiler guru who seems to think you need[/color][/color]
> the[color=green][color=darkred]
> > > > cast.
> > > > > I thought it too, up until I started posting here!
> > > > >
> > > > > Thanks,
> > > > >
> > > > > Chris
> > > > >
> > > > Even better, here is the email itself. Please help!
> > > >
> > > > <start email>
> > > > First, Casts from void * are necessary both in C and C++. This is[/color][/color][/color]
from[color=blue][color=green]
> > the[color=darkred]
> > >
> > > Casts from void* are necessary in C++, not in C.[/color]
> >
> > I am aware... I'm fishing for more info! Perhaps if I reposted again[/color][/color]
and[color=blue][color=green]
> > said you were wrong I'll get more...
> >
> > You're WRONG![/color]
>
> void* is implicitly converted to the destination pointer type (C99[/color]
§6.3.2.3[color=blue]
> and §7.20.3.1).
>[color=green][color=darkred]
> > >
> > > > same reason you told me: otherwise, if the compiler wouldn't
> > > > know what is the size of the object which is pointed at, it might[/color][/color][/color]
get[color=blue][color=green][color=darkred]
> > > > confused with arithmetic operations.[/color][/color]
>
> sizeof ?
>[color=green]
> >You can ask him where did he
> > learned[color=darkred]
> > > > this rule from. tell me if you want me to correspond directly with[/color][/color]
> him.[color=green][color=darkred]
> > > >
> > > > Second, a possible reason to use integral types for addresses rather[/color]
> > than[color=darkred]
> > > > void *, is that in order to perform bitwise operations on an
> > > > address, you have to use operators of an integral type.[/color][/color]
>
> It's also said in the standard (C99), part 6 of §6.3.2.3 that :
> "Any pointer type may be converted to an integer type. Except as[/color]
previously[color=blue]
> specified, the result is implementation-defined. If the result cannot be
> represented in the integer type, the behavior is undefined. The result[/color]
need[color=blue]
> not be in the range of values of any integer type."
>
> Is he/she sure that he/she can always hold his adressses with an integral
> type ? It implies sizeof(the famous integral type) >= sizeof(void*).
>
> There is a way in C99 to hold pointers and adresses with integers thanks[/color]
to[color=blue]
> the types intptr_t and uintptr_t. (C99 7.18.1.4), but I'm not sure it's
> possible in C90..
>
> Regis
>[color=green][color=darkred]
> > > > <end email>
> > > >
> > >
> > > Regis
> > >
> > >[/color]
> >[/color]
>
>[/color]
Do you know if this was also a standard in C89/C90? If so, it would
strengthen my argument since the recent response was that "GCC-derived
compilers don't fully support C99 yet." Not sure if it's true... Any
thoughts?

Not sure what she meant with arithmetic operations... you don't normally do
arithmetic on pointers, but if you did, I guess you could just cast to an
integral type of the correct size, correct?

The fact is I am very uncomfortable holding addresses in an integral data
type. Usually we let the compiler choose the addressing scheme (depending
on the memory model) and it should (if it is smart) know how big to make
pointers. But if all of our generic pointers are integral and need to be
casted to pointers, it's our own code that must know what the memory model
is.

Thanks in advance!

Chris

[Chris Torek]

Re: struct my_struct *p = (struct my_struct *)malloc(sizeof (struct my_struct));

In article <GSCfc.89809$dP 1.269709@newsc. telia.net>
Chris Fogelklou <chris.fogelklo u@comhem.se> writes:[color=blue]
>Is there really that much wrong with making code compatible with both C and
>C++? If we leave the cast in there, the code could be copied and pasted
>into a C++ library verbatim. ...[/color]

There is nothing inherently wrong with it, but I see it as a waste of
effort in most cases.

There are quite a few subtle differences between C and C++, so that
one can write programs that are syntactically valid in both languages,
compile in both languages, yet mean something different in each
language. The problem is similar to getting Americans and Brits
to understand each other: when an American committee "tables" a
subject it is put aside to stop discussion, while the British
committee "tables" the subject to bring it up and begin discussion.

(I posted an example earlier today in which "sizeof type" changes
when the code is compiled in the alternate language. Look for
"struct scopetrick".)

More typically, good C code often fails to compile at all as C++
code (because -- among other things -- it omits casts that C++
requires); and of course good C++ code generally uses "new" instead
of malloc, or -- even better -- uses container classes.
--
In-Real-Life: Chris Torek, Wind River Systems
Salt Lake City, UT, USA (40°39.22'N, 111°50.29'W) +1 801 277 2603
email: forget about it http://web.torek.net/torek/index.html
Reading email is like searching for food in the garbage, thanks to spammers.

[CBFalconer]

Re: struct my_struct *p = (struct my_struct *)malloc(sizeof (structmy_struc t));

Chris Torek wrote:[color=blue]
> Chris Fogelklou <chris.fogelklo u@comhem.se> writes:
>[color=green]
>> Is there really that much wrong with making code compatible with
>> both C and C++? If we leave the cast in there, the code could
>> be copied and pasted into a C++ library verbatim. ...[/color]
>
> There is nothing inherently wrong with it, but I see it as a
> waste of effort in most cases.
>
> There are quite a few subtle differences between C and C++, so
> that one can write programs that are syntactically valid in both
> languages, compile in both languages, yet mean something
> different in each language. The problem is similar to getting
> Americans and Brits to understand each other: when an American[/color]
....

Back when I was young and in my prime there was this amiable, but
poverty stricken Yank who met this foxy Brit chick. Nature took
its course, but then she told him: "I am getting divorced, with a
big settlement. Meet me after the divorce, but meanwhile I have
to stay pristine." And she handed him an envelope and told him to
open it after the day was over.

Well, he followed instructions, and opened it and read: "Until
7/6, noon, in Trafalger Square.". Since it was January, he went
off and did other things, such as roping calves etc., and returned
to London on 7/6. He never found her again.

She meant every word of it, and she was there on 7/6, but never
found him again.

Your mission, should you care to accept it, is to explain this
paradox. Alternate timelines or universes will not be accepted.

--
fix (vb.): 1. to paper over, obscure, hide from public view; 2.
to work around, in a way that produces unintended consequences
that are worse than the original problem. Usage: "Windows ME
fixes many of the shortcomings of Windows 98 SE". - Hutchison

[Severian]

Re: struct my_struct *p = (struct my_struct *)malloc(sizeof (struct my_struct));

On Fri, 16 Apr 2004 04:29:22 GMT, CBFalconer <cbfalconer@yah oo.com>
wrote:
[color=blue]
>Chris Torek wrote:[color=green]
>> Chris Fogelklou <chris.fogelklo u@comhem.se> writes:
>>[color=darkred]
>>> Is there really that much wrong with making code compatible with
>>> both C and C++? If we leave the cast in there, the code could
>>> be copied and pasted into a C++ library verbatim. ...[/color]
>>
>> There is nothing inherently wrong with it, but I see it as a
>> waste of effort in most cases.
>>
>> There are quite a few subtle differences between C and C++, so
>> that one can write programs that are syntactically valid in both
>> languages, compile in both languages, yet mean something
>> different in each language. The problem is similar to getting
>> Americans and Brits to understand each other: when an American[/color]
>...
>
>Back when I was young and in my prime there was this amiable, but
>poverty stricken Yank who met this foxy Brit chick. Nature took
>its course, but then she told him: "I am getting divorced, with a
>big settlement. Meet me after the divorce, but meanwhile I have
>to stay pristine." And she handed him an envelope and told him to
>open it after the day was over.
>
>Well, he followed instructions, and opened it and read: "Until
>7/6, noon, in Trafalger Square.". Since it was January, he went
>off and did other things, such as roping calves etc., and returned
>to London on 7/6. He never found her again.
>
>She meant every word of it, and she was there on 7/6, but never
>found him again.
>
>Your mission, should you care to accept it, is to explain this
>paradox. Alternate timelines or universes will not be accepted.[/color]

Too easy. June 7th != July 6th. However, your language point is
evident.

--
Sev

[Christian Bau]

Re: struct my_struct *p = (struct my_struct *)malloc(sizeof (struct my_struct));

In article <9gou709pl8pkpa j8k8eni61qjkufd eihlj@4ax.com>,
Severian <severian@chlam ydia-is-not-a-flower.com> wrote:
[color=blue]
> On Fri, 16 Apr 2004 04:29:22 GMT, CBFalconer <cbfalconer@yah oo.com>
> wrote:
>[color=green]
> >Chris Torek wrote:[color=darkred]
> >> Chris Fogelklou <chris.fogelklo u@comhem.se> writes:
> >>
> >>> Is there really that much wrong with making code compatible with
> >>> both C and C++? If we leave the cast in there, the code could
> >>> be copied and pasted into a C++ library verbatim. ...
> >>
> >> There is nothing inherently wrong with it, but I see it as a
> >> waste of effort in most cases.
> >>
> >> There are quite a few subtle differences between C and C++, so
> >> that one can write programs that are syntactically valid in both
> >> languages, compile in both languages, yet mean something
> >> different in each language. The problem is similar to getting
> >> Americans and Brits to understand each other: when an American[/color]
> >...
> >
> >Back when I was young and in my prime there was this amiable, but
> >poverty stricken Yank who met this foxy Brit chick. Nature took
> >its course, but then she told him: "I am getting divorced, with a
> >big settlement. Meet me after the divorce, but meanwhile I have
> >to stay pristine." And she handed him an envelope and told him to
> >open it after the day was over.
> >
> >Well, he followed instructions, and opened it and read: "Until
> >7/6, noon, in Trafalger Square.". Since it was January, he went
> >off and did other things, such as roping calves etc., and returned
> >to London on 7/6. He never found her again.
> >
> >She meant every word of it, and she was there on 7/6, but never
> >found him again.
> >
> >Your mission, should you care to accept it, is to explain this
> >paradox. Alternate timelines or universes will not be accepted.[/color]
>
> Too easy. June 7th != July 6th. However, your language point is
> evident.[/color]

Many years ago, a C++ framework that I investigated for its usefulness
changed a constructor from

Point::Point (int width, int height);

to

Point::Point (int vertical, int horizontal);

I decided not to use that framework...

[Régis Troadec]

Re: struct my_struct *p = (struct my_struct *)malloc(sizeof (struct my_struct));


"Dan Pop" <Dan.Pop@cern.c h> a écrit dans le message de
news:c5mf3u$b63 $1@sunnews.cern .ch...[color=blue]
> In <c5mdq4$msh$1@n ews-reader4.wanadoo .fr> "Régis Troadec"[/color]
<regt@wanadoo.f r> writes:[color=blue]
>[/color]

Hi,
[color=blue][color=green]
> >"Dan Pop" <Dan.Pop@cern.c h> a écrit dans le message de
> >news:c5mblu$1r p$3@sunnews.cer n.ch...[color=darkred]
> >> In <c5maek$b90$1@n ews-reader4.wanadoo .fr> "Régis Troadec"[/color]
> ><regt@wanadoo. fr> writes:[color=darkred]
> >>
> >>
> >> >"Chris Fogelklou" <chris.fogelklo u@comhem.se> a écrit dans le message[/color][/color][/color]
de[color=blue][color=green][color=darkred]
> >> >news:3Hxfc.897 62$dP1.269154@n ewsc.telia.net. ..
> >> >
> >> >> You're WRONG!
> >> >
> >> >void* is implicitly converted to the destination pointer type (C99[/color]
> >§6.3.2.3[color=darkred]
> >> >and §7.20.3.1).
> >>
> >> You're WRONG!
> >>
> >> There is NOTHING in C99 §6.3.2.3 or §7.20.3.1 supporting your[/color][/color][/color]
assertion.[color=blue][color=green]
> >
> >Let's correct it : void * may be converted to a pointer to any incomplete[/color][/color]
or[color=blue][color=green]
> >object type. As well, void* may be converted from a pointer to any
> >incomplete or object type. This is what I read in C99 §6.3.2.3.
> >You were probably hurt by seeing "void* IS ... converted".[/color]
>
> I was hurt by not seeing *anywhere* in 6.3.2.3 that the conversion
> doesn't require a cast. I am still hurt... ;-)[/color]

Perhaps one day I'll be right and exhaustive...
Let's now add C99 §6.5.4 concerning the cast operator and the further
reference to simple assignments in §6.5.16.1.
I'm too lazy to find out the interesting and relevant parts in the
paragraphs but I think the reader will find something that prove the
conversion doesn't require a cast.
Am I complete now, or is something missing ?

Regards,

Regis
[color=blue]
>
> Dan
> --
> Dan Pop
> DESY Zeuthen, RZ group
> Email: Dan.Pop@ifh.de[/color]