libiconv linker errors

[Uncommon]

I'm synced to c2d3af2 (current master), and I've run the bootstrap script and tried cleaning, but I always get these linker errors when building the framework target:

Undefined symbols for architecture x86_64:
  "_libiconv", referenced from:
      _git_path_iconv in libgit2.a(path.c.o)
  "_libiconv_close", referenced from:
      _git_path_iconv_clear in libgit2.a(path.c.o)
  "_libiconv_open", referenced from:
      _git_path_iconv_init_precompose in libgit2.a(path.c.o)

[arrbee]

Do you happen to have iconv installed via MacPorts or another alternative version of iconv?

[Uncommon]

Isn't it a standard library? I haven't installed it explicitly.

[arrbee]

It is. One common source of problems is for people who are not using the standard version. What version of OS X are you running?

[arrbee]

Oh, and are you using MacPorts even if you didn't install it explicitly?

[Uncommon]

I've never used MacPorts. I'm on OS X 10.9.2.

[Uncommon]

The way the Objective Git framework target is set up, it's linked using the linker build phase (rather than a linker flag), using libiconv.dylib as referenced in the project, which according to Xcode is coming from the 10.9 SDK.

[Uncommon]

Also, Xcode 5.1.1.

[jspahrsummers]

If you remove it from the Link Binaries With Libraries phase, and instead add -liconv to the linker flags, does it work then?

[Uncommon]

Nope, same error. I also upgraded to 10.9.3, and tried a fresh clone (not as a submodule of my other repo).

[Uncommon]

Also tried changing the base SDK to 10.8.

[Uncommon]

I reinstalled Xcode in case the library was corrupted. No dice.

https://trac.macports.org/ticket/38851 seemed relevant, but the solution there did not help.

[Uncommon]

I tried making a simple project, adding a call to iconv_open() to the command line tool template, and with the -liconv linker flag it builds just fine.

I noticed that the library search paths for ObjectiveGit are . and External, which doesn't explicitly include /usr/lib, but apparently that doesn't matter; adding it doesn't help. What else could be making the difference?

[jspahrsummers]

Sorry for the radio silence—this is just super weird. We've still never seen this problem, on our machines or CI. 😕

You're using Xcode 5.1, right?

[Uncommon]

Xcode 5.1.1 as noted above.

Yeah, it's pretty weird. I didn't have this problem on the other machines I've worked on.

[tqc]

I'm getting the same issue building for iOS. The problem appears to be something to do with incompatible iconv versions - libgit2 is built using /opt/local/include/iconv.h (latest from macports), which contains

#define _LIBICONV_VERSION 0x010E 
#ifndef LIBICONV_PLUG
#define iconv_open libiconv_open
#endif
extern iconv_t iconv_open (const char* tocode, const char* fromcode);

When linking the app project in Xcode, it uses /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS.sdk/usr/include/iconv.h, which contains

#define _LIBICONV_VERSION 0x010B 
iconv_t iconv_open (const char* /*tocode*/, const char* /*fromcode*/);

Not sure where the proper place to define LIBICONV_PLUG is, but adding it to iconv.h seems to allow a successful build for arm64, which wasn't working previously. However, I then get other linker errors for x86_64 (iOS simulator for newer devices), and i386, which was previously working now fails.

[tqc]

Adding the following to CMakeLists.txt seems to work

IF(${CMAKE_OSX_ARCHITECTURES} MATCHES "(arm64|x86_64)")
    ADD_DEFINITIONS(-DLIBICONV_PLUG)
ENDIF()

The other linker errors turned out to be the difference between running script/update_libgit2_ios from Xcode and the command line.

Now to see if it actually runs...

[Uncommon]

That doesn't fix it for me. It looks like the header is being found at /opt/local/include/iconv.h, but the library is being linked from /usr/lib/libiconv.dylib, and the symbols are different. So what's the best way to ensure the correct header path?

[Uncommon]

...and apparently /opt/local is a MacPorts thing, so I guess I'm using it after all. I don't remember installing it explicitly.

[Napoleon-BlownApart]

I'm not sure if you've solved this, but I've finally been able to build successfully. Haven't tested the result yet.

I noticed that the symlinks in the External folder were incorrectly pointing to "/usr/local/opt/".
So I deleted these and recreated them by pointing them to /opt/local/lib. I did this for:
libssl.a, libcrypto.a, and libiconv.a.

So, my "Other Linker Flags" for the Mac Target are as follows:

-lgit2
-force_load
/opt/local/lib/libssh2.a  (which I could have made a symlink in External like the others)
External/libssl.a
External/libcrypto.a
External/libgit2.a
External/libiconv.a

Hope this is correct and helps.

Cheers,
Nap

[soniccat]

I had the same problem. I noticed that after launching ./script/update_libgit2 I had this line:
-- Found Iconv: -L/opt/local/lib -liconv
it meant that it took wrong lib.
After deactivating the lib (sudo port -f deact libiconv), removing the wrong libgit2 and rebuilding it again I saw the right path
-- Found Iconv: -L/usr/lib -liconv
And then I didn't see these linking errors.

[joshaber]

Pretty old and we've recently cleaned up the libgit2 building process: #483