hi there
i m trying to convert (viod *) data to (unsigned char) using
reinterpret_cas t as following
void *aData; // some data already provided
unsigned char c = reinterpret_cas t<unsingned char>(aData);
and the gcc is giving me the following error
-------------------------------------------------
reinterpret_cas t from
`void*' to `unsigned char' loses precision
-------------------------------------------------
is this what i m doing is valid Standard C++ ???
I have kept settings to treat all warning as Errors, so this is giving me
error
any suggestions ??
6  2795 
On Tue, 13 Jul 2004 12:59:59 +0530, hack_tick <ha*******@yaho o.com> wrote: hi there
i m trying to convert (viod *) data to (unsigned char) using
reinterpret_cas t as following
void *aData; // some data already provided
unsigned char c = reinterpret_cas t<unsingned char>(aData);
and the gcc is giving me the following error
-------------------------------------------------
reinterpret_cas t from
`void*' to `unsigned char' loses precision
-------------------------------------------------
is this what i m doing is valid Standard C++ ???
I have kept settings to treat all warning as Errors, so this is giving me
error
any suggestions ??
Converting void* to unsigned char is a completely meaningless thing to do.
As the warning states, void* is four bytes (probably) and unsigned char is
one byte, so you are losing information.
Are you sure you didn't mean to convert to unsigned char*? That would make
a lot more sense.
john
"hack_tick" <ha*******@yaho o.com> wrote in message
news:2l******** ****@uni-berlin.de... hi there
i m trying to convert (viod *) data to (unsigned char) using
reinterpret_cas t as following
void *aData; // some data already provided
unsigned char c = reinterpret_cas t<unsingned char>(aData);
and the gcc is giving me the following error
reinterpret_cas t means like telling the compiler that I know better than you
here, just carry out what I am saying. That's unsafe and compiler warns you
here that
it could be that the destination type is not big enough to hold the source
value. reinterpret_cas t is very much standard C++.
hi there
"John Harrison" <jo************ *@hotmail.com> wrote in message
news:opsa2ey3vg 212331@andronic us...
[..] Converting void* to unsigned char is a completely meaningless thing to do.
As the warning states, void* is four bytes (probably) and unsigned char is
one byte, so you are losing information.
Are you sure you didn't mean to convert to unsigned char*? That would make
a lot more sense.
opps !! actually my mistake, it was (unsigned char *), sorry and thankx for
making me realize that
:-)
hack_tick wrote: hi there
"John Harrison" <jo************ *@hotmail.com> wrote in message
news:opsa2ey3vg 212331@andronic us...
[..]
Converting void* to unsigned char is a completely meaningless thing to do.
As the warning states, void* is four bytes (probably) and unsigned char is
one byte, so you are losing information.
Are you sure you didn't mean to convert to unsigned char*? That would make
a lot more sense.
opps !! actually my mistake, it was (unsigned char *), sorry and thankx for
making me realize that
:-)
I believe that you can use static_cast<> to cast a void* into
any-other-type*
hi there
"red floyd" <no*****@here.d ude> wrote in message
news:ip******** *********@newss vr25.news.prodi gy.com...
[..] I believe that you can use static_cast<> to cast a void* into
any-other-type*
yup we can, i was doing all in hurry and forgt the actual data it was
containing(addr ess)
thanks for your reply :-)
hack_tick wrote: hi there
"red floyd" <no*****@here.d ude> wrote in message
news:ip******** *********@newss vr25.news.prodi gy.com...
[..]
I believe that you can use static_cast<> to cast a void* into
any-other-type*
yup we can, i was doing all in hurry and forgt the actual data it was
containing(addr ess)
thanks for your reply :-)
just to add , reinterpret cast is best when you try to convert an
integer to a pointer. ( assuming the integer contains a valid address).
It is no doubt dangerous, ( and not portable, to add ) , but assuming
you know what you are doing , then it is best used in scenarios to
convert an integer to a pointer.
HTH
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