c++ cast bug ?

c++ cast bug ?

[John Levon]

in 3.0.1 but also in rh gcc 2.96 :

void opp_get_options(int argc, char const *argv[])
{
	...
       /* Some old version of popt needs the cast to char ** */
       optcon = poptGetContext(NULL, argc, const_cast<char **>(argv), options, 0);


compiling this c++ :

oprofpp.c:143: cannot convert `char **' to `const char **' for argument
`3' to `poptGetContext (const char *, int, const char **, const
poptOption *, int)'

how can this be right (where is implicit cast to const version of char **) ? 

if it's wrong or not, how do I fix my code to work ?

thanks
john

-- 
"If you're not part of the problem, you're part of the problem space." 

Re: c++ cast bug ?

[Alexandre Oliva]

On Sep 20, 2001, John Levon <moz@compsoc.man.ac.uk> wrote:

> oprofpp.c:143: cannot convert `char **' to `const char **' for argument
> `3' to `poptGetContext (const char *, int, const char **, const
> poptOption *, int)'

> how can this be right (where is implicit cast to const version of char **) ? 

The argument was const_casted to char**, but the parameter has type
const char**, and there's no implicit conversion from char** to const
char**.

> if it's wrong or not, how do I fix my code to work ?

Just take the const_cast out.

-- 
Alexandre Oliva   Enjoy Guarana', see http://www.ic.unicamp.br/~oliva/
Red Hat GCC Developer                  aoliva@{cygnus.com, redhat.com}
CS PhD student at IC-Unicamp        oliva@{lsd.ic.unicamp.br, gnu.org}
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