Hello all
I would like to give a certain name to a certain global variable. Unfortunately,
this name is already used in math.h for a mathematical function. Worse, I do
need to use maths library and therefore have to include math.h. Thus my compiler
reports conflicting declarations of the same name.
Does anyone know any reasonably elegant way to resolve this conflict? I
understand that I can give up and choose another name, but somehow not happy
with that.
Any advice would be much appreciated!
- V.
Nov 14 '05
16  3599 
Emmanuel Delahaye <em***@YOURBRAn oos.fr> wrote: Richard Bos wrote on 11/08/04 : (BTW, it's not a C question)
Yes, it is: you cannot have two conflicting declarations of the same
identifier, hence the problem. Of course, the answer is "don't do that,
then", but that doesn't make the question off-topic.
Ok. I meant that it's not specific to C.
Not completely, but it's not a completely general problem, either. Many
languages have ways to specify the namespace of an identifier, allowing
you to do what the OP wants to do. C does not. It's true that C isn't
the only language which doesn't; but that alone doesn't make it
off-topic.
Richard
"Arthur J. O'Dwyer" <aj*@nospam.and rew.cmu.edu> wrote: On Wed, 11 Aug 2004, CBFalconer wrote:
place. For example, if you #include <stdlib.h> and write your own
routine malloc(), the library routine for malloc may not get
loaded. However the realloc() routine may well call the original
malloc, and if rerouted its assumptions are no longer valid. All
of these may be called behind your back in the initialization
code.
Amplification: It's not just the library-linkage problem. We
have sentences in the Standard that say explicitly things like
[#3] The implementation shall behave as if no library
function calls the rand function.
and yet it's /still/ UB to define 'extern int rand;'. This may be
for the benefit of dumb optimizers who can now inline any standard
library routine they like, without checking symbol tables or whatnot.
Not just that. It would be allowed, for example, to
- save the state of rand();
- call rand() to get a random number;
- restore the previous state.
If the programmer can replace rand(), this is no longer possible.
Of course, this is hardly likely to be useful with rand() itself; but it
is a possibility.
Richard
Richard Bos wrote:
.... snip ...
Not completely, but it's not a completely general problem, either.
Many languages have ways to specify the namespace of an identifier,
allowing you to do what the OP wants to do. C does not. It's true
that C isn't the only language which doesn't; but that alone
doesn't make it off-topic.
Yes, C does have namespaces. To grossly simplify, anything
starting with a '_' is in system space, and most ordinary
identifiers are in user space. They just aren't named
namespaces. struct and enum tags are another area.
--
Chuck F (cb********@yah oo.com) (cb********@wor ldnet.att.net)
Available for consulting/temporary embedded and systems.
<http://cbfalconer.home .att.net> USE worldnet address!
"pete" <pf*****@mindsp ring.com> wrote The first question that comes to my mind is,
is that certain name, a reserved identifier?
(In other words, "Which name?")
It would be a sin to tell you.
Malcolm wrote:
"pete" <pf*****@mindsp ring.com> wrote The first question that comes to my mind is,
is that certain name, a reserved identifier?
(In other words, "Which name?")
It would be a sin to tell you.
Does it start with an underscore ?
Malcolm wrote: "pete" <pf*****@mindsp ring.com> wrote
The first question that comes to my mind is,
is that certain name, a reserved identifier?
(In other words, "Which name?")
It would be a sin to tell you.
And cos we'd have to tan your floor and say pow!
On Thu, 12 Aug 2004 19:15:56 +0100, "Malcolm"
<ma*****@55bank .freeserve.co.u k> wrote:
"pete" <pf*****@mindsp ring.com> wrote The first question that comes to my mind is,
is that certain name, a reserved identifier?
(In other words, "Which name?")
It would be a sin to tell you.
Just be cos?
--
Al Balmer
Balmer Consulting re************* ***********@att .net This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics | |
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