07-21-2010, 07:04 PM

Hi,

I am pretty new to XCode and Web Objects/ Objective C apps.

I am trying to build an existing Obj C app on my local machine that runs OS X 10.6.2 and getting the below error:

My XCode version is 3.2 and the cc used is gcc-4.0

regexp_stuff.m:1501:23: error: macro "strncpy" requires 3 arguments, but only 1 given
regexp_stuff.m: In function ‘_MOregsub’:
regexp_stuff.m:1501: error: ‘strncpy’ redeclared as different kind of symbol
regexp_stuff.m:1501: warning: unused variable ‘strncpy’


Please let me know if you have any pointers on how to debug this issue.

Thanks!

07-21-2010, 11:22 PM

It would really help to see your code - just seeing the error only gives part of the picture.

For example:

" regexp_stuff.m:1501:23: error: macro "strncpy" requires 3 arguments, but only 1 given "

would be given probably because there is a functioned defined as strncpy that is part of the strings library (in strings.h) and the prototype looks like:

char *strncpy(char *s1, const char *s2, size_t n);

so the compiler is wondering how come with a function that requires three parameters, you've only supplied 1.

in this:

regexp_stuff.m: In function ‘_MOregsub’:
regexp_stuff.m:1501: error: ‘strncpy’ redeclared as different kind of symbol
regexp_stuff.m:1501: warning: unused variable ‘strncpy’

In a function you have created, it appears you have defined strncpy as something else, which is giving the compiler a headache because it's already aware of a function called strncpy, you don't want local variables to have the same name as functions otherwise you run into ugly errors.

The last one is potentially nothing important - it's just stating you declared a variable but didn't actually use it in the function.

It's kind of like doing:

int addInts(int a, int b)
{
int x;

return a+b;
}

I declared x but didn't actually use it in the function - the compiler is letting you know that you have a variable in there that is either wasted space or you managed to forget to include it in what you were doing.