Hello, I have a problem with compiling my code...

Platform: Ubuntu Linux 10.04
Compiler: gcc (Ubuntu 4.4.3-4ubuntu5) 4.4.3
IDE: Netbeans 6.9.1

My C program is required to exclusively deal with Unicode. I can use these functions just fine: wcscpy(), wcslen(), mbstowcs(), wcstombs(), snprintf()

The problem seems to only be when I use this function: swprintf()

Here are the headers I am including in the order I am including them:

#include <stdlib.h>
#include <string.h>
#include <math.h>
#include <stdio.h>
#include <wchar.h>
#include <wctype.h>

This is the line of code which gives me an error:

ret = __builtin_apply( (void *)swprintf, args, 1024 );

This is the error I get. Its the only error I get:

456: error: ‘swprintf’ undeclared (first use in this function)
456: error: (Each undeclared identifier is reported only once
456: error: for each function it appears in.)

In the NetBeans IDE, I right click the function name "swprintf" and click "Navigate / Go to Definition". It takes me to line 602 of "wchar.h":

/* Write formatted output of at most N characters to S.  */
extern int swprintf (wchar_t *__restrict __s, size_t __n,
		     __const wchar_t *__restrict __format, ...)
     __THROW /* __attribute__ ((__format__ (__wprintf__, 3, 4))) */;

So curiously enough, NetBeans can see it just fine. Why can't gcc? Remember, all the other wchar_t functions did not have any compiler errors. Also keep in mind that this is not a linker error.

Any ideas?

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How are you compiling in GCC? That error usually comes from not supplying the required libraries at compile time.

I will admit that I don't completely know my way around the NetBeans IDE as well as I should. This is the only meaningful line of code in the "Build" tab right before the error shows up:

gcc    -c -g -I/usr/include/freetype2/freetype -I/usr/include/freetype2 -I/usr/local/include/SDL -I../shared -MMD -MP -MF build/Debug/GNU-Linux-x86/_ext/819228780/iString.o.d -o build/Debug/GNU-Linux-x86/_ext/819228780/iString.o ../shared/iString.c

iString.c/h being the file name of my code containing the error.

There is nothing in the C compiler options menu for the current project in Netbeans which adds any new information to this problem. It has all the appropriate include folders:

/usr/include/freetype2/freetype
/usr/include/freetype2
/usr/local/include/SDL
../shared

shared being where my code is located.

Here are the libraries I am linking at link time. I highly doubt that the linker is involved here:

GLU
GLUT
FreeType
SDL
SDLmain

So its basically OpenGL and its helper library, the FreeType library, and the SDL interface library.

If I haven't answered your question completely enough, please help me find that information for you in NetBeans. I can provide screenshots if that is helpful.

I will admit that I don't completely know my way around the NetBeans IDE as well as I should. This is the only meaningful line of code in the "Build" tab right before the error shows up:

gcc    -c -g -I/usr/include/freetype2/freetype -I/usr/include/freetype2 -I/usr/local/include/SDL -I../shared -MMD -MP -MF build/Debug/GNU-Linux-x86/_ext/819228780/iString.o.d -o build/Debug/GNU-Linux-x86/_ext/819228780/iString.o ../shared/iString.c

iString.c/h being the file name of my code containing the error.

There is nothing in the C compiler options menu for the current project in Netbeans which adds any new information to this problem. It has all the appropriate include folders:

/usr/include/freetype2/freetype
/usr/include/freetype2
/usr/local/include/SDL
../shared

shared being where my code is located.

Here are the libraries I am linking at link time. I highly doubt that the linker is involved here:

GLU
GLUT
FreeType
SDL
SDLmain

So its basically OpenGL and its helper library, the FreeType library, and the SDL interface library.

If I haven't answered your question completely enough, please help me find that information for you in NetBeans. I can provide screenshots if that is helpful.

Agree with you that it doesnt seem to be a linker issue
Which gcc version you are using?

My first post mentioned the version of gcc I was using, but here it is again written a different way:

[b]bash:~$[/b] gcc --version
gcc (Ubuntu 4.4.3-4ubuntu5) 4.4.3
Copyright (C) 2009 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

My first post mentioned the version of gcc I was using, but here it is again written a different way:

[b]bash:~$[/b] gcc --version
gcc (Ubuntu 4.4.3-4ubuntu5) 4.4.3
Copyright (C) 2009 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

My mistake.. i dint notice it..
Ok, Is this function definition protected by some macros???
Anyways try reading this link..
mite provide some help

EDIT: Also in my header file i dont see that 'extern' keywork in front of swprintf()
I am using mingw...
It could mean that your c library dont have the implementation... :S

Looking at "wchar.h", I notice this piece of code preceding the swprintf declaration as well as some other functions:

#if defined __USE_ISOC95 || defined __USE_UNIX98
__BEGIN_NAMESPACE_STD

I don't know how many nested preprocessor conditions are involved with that code, but either way, it seems I found a workaround to my problem....

My fix was as simple as appending the missing declaration to the top of my C code as shown here:

#include <stdlib.h>
#include <string.h>
#include <math.h>
#include <stdio.h>
#include <wchar.h>
#include <wctype.h>

/* Write formatted output of at most N characters to S.  */
extern int swprintf (wchar_t *__restrict __s, size_t __n,
		     __const wchar_t *__restrict __format, ...)
     __THROW /* __attribute__ ((__format__ (__wprintf__, 3, 4))) */;

Then I tested swprintf and it behaved as it should. Its strange that it was blocked in the first place. Well it doesn't matter now, as long as it works I'm happy.

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