#1231 libiconv can't be linked with executables

Hello!

i've tried to build executable with using of
libiconv-1.11-mingwPORT-20070423-1.tar.bz2

and I got following:
C:/MinGW/lib/libiconv.a(iconv.o):iconv.c:(.text+0xe8606): undefined reference to `__errno'
C:/MinGW/lib/libiconv.a(iconv.o):iconv.c:(.text+0xe863a): undefined reference to `__errno'
C:/MinGW/lib/libiconv.a(iconv.o):iconv.c:(.text+0xe8714): undefined reference to `__errno'
C:/MinGW/lib/libiconv.a(iconv.o):iconv.c:(.text+0xe8764): undefined reference to `__errno'
C:/MinGW/lib/libiconv.a(iconv.o):iconv.c:(.text+0xe8782): undefined reference to `__errno'
C:/MinGW/lib/libiconv.a(iconv.o):iconv.c:(.text+0xe8910): more undefined references to `__errno' follow
collect2: ld returned 1 exit status

source was:
#include <iconv.h>
int main(void) { iconv_open(0,0); return 0; }

command line was:
gcc -O2 ic_test.c -o ic_test.exe -liconv 2>ic_err

[Keith Marshall]

Works fine for me.

How did you build the mingwPORT?
Did that build complete successfully?
Can you build a simple, self-contained application using `errno'?

<example>
#include <stdio.h>
#include <errno.h>

int main()
{
FILE *input;
if( (input = fopen( "nonsuch", "r" )) == NULL )
{
perror( "fopen" );
fprintf( stderr, "errno = %d\n", errno );
}
return 0;
}
</example>

[Anonymous]

I'm using binaries from sf.net download page!
WIth using of MinGW i'm able to build executable of biew project:
https://sourceforge.net/project/showfiles.php?group_id=1475&package_id=1454&release_id=653021
but without libiconv support.

[Keith Marshall]

You said you were using libiconv-1.11-mingwPORT, which is *not* a binary -- you have to build it! If you didn't build it, then where did your iconv.h, and your libiconv.a come from?

FTR, the unresolved `__errno' symbol is defined in libmsvcrt.a, (which you do *not* need to, and indeed *shouldn't*, specify explicitly on your command line), as a reference to a standard DLL symbol; that should be available to *all* MinGW applications, so your problem may not be specifically related to libiconv.a usage. That is where I am going, when I ask you to run a specific self-contained test sample. Whatever else you can, or can't build is irrelevant. If you don't give full answers to my questions, then I'm sorry, but I can't help you further.

AFAICT, there is no reportable bug here. You may have a faulty MinGW installation, and should seek assistance on the mailing list.

[Anonymous]

libmsvcrt.a defines _errno symbol with single '_' leading character only? but not __errno!

[Keith Marshall]

Real info, copied and pasted from my own Win2K system:

$ nm --print-file /mingw/lib/libiconv.a | grep errno
d:/usr/mingw-3.4.5/lib/libiconv.a:iconv.o: U __errno

$ nm --print-file /mingw/lib/libmsvcrt.a | grep errno
d:/usr/mingw-3.4.5/lib/libmsvcrt.a:dayhs00152.o:00000000 T __errno
d:/usr/mingw-3.4.5/lib/libmsvcrt.a:dayhs00152.o:00000000 I __imp___errno
d:/usr/mingw-3.4.5/lib/libmsvcrt.a:dayhs00037.o:00000000 T ___doserrno
d:/usr/mingw-3.4.5/lib/libmsvcrt.a:dayhs00037.o:00000000 I __imp____doserrno

Note that the symbol is `__errno' in *both* cases; (GCC adds an extra leading underscore to the symbol name stored in the object file, when that is PE-COFF format). This symbol is unresolved in libiconv.a; defined in libmsvcrt.a

If yours isn't like this, then it isn't correctly installed.

You still haven't bothered to answer the questions I posed! See:
http://www.chiark.greenend.org.uk/~sgtatham/bugs.html

for why I have no further help to offer you.

[Kelley567]

Please try libiconv-1.12 mingwPORT if good.
https://sourceforge.net/tracker2/?func=detail&aid=2531139&group_id=2435&atid=752210

source:
#include <windows.h>
#include <stdio.h>
#include <errno.h>
#include <iconv.h>

int main(void) {
iconv_t i;
const char c1[]="dummy";
const char c2[]="utf-8";

i = iconv_open(c1, c2);
printf("iconv_t = %d\n", i);
printf("errno = %d\n", errno);
return EXIT_SUCCESS;
}

Test environment:
gcc version 3.4.5(mingw-vista special r3)
GNU ld version 2.17.50 20060824
GNU ld(GNU Binutils) 2.19

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