duplicate-symbol

A is a module project. There are some test targets and the relevant reusable code is compiled in a separate (static library) target. A uses the third party Lumberjack logging library. The Lumberjack code was simply dropped into the project. B is a different module project, but otherwise it has the same properties as A . C is the main project. It depends on A and B . It links the libraries of A and B . Compiling C will result in duplicate Lumberjack symbols. How can I have multiple separate module projects so that... they don't know of each other, use the same third party code, can be compiled

Some background - I've built a custom Framework using Diney's guide at http://db-in.com/blog/2011/07/universal-framework-iphone-ios-2-0/ Its built for both armv6 / armv7 , its an ARC-based framework, compiled with a depolyment target of 4.3. When i put the resulting framework in a 5.0 project it works great, but when i put it in a 4.3 project (ARC or non-arc, doesnt matter), i get the following which i can't really understand ... I've also tried adding libarclite.a manually but it didn't change anything. ld: duplicate symbol _objc_retainedObject in /Users/freak4pc/Project/MyFramework.framework

I have the following code layout header.h #ifndef _header_h #define _header_h void empty(float *array, int l) { int i; for (i=1 ; i<=l ; i++) { array[i]=0; } } #endif and two files (lets call them file1.c and file2.c) #include "header.h" void function/*1 or 2*/(){ .... empty(a,b); .... } So compiling works fine but the linker command fails as the compiler says that there is a duplicate function definition. How can I avoid that with still using the header file? It is working fine when I only define the function in the header and create another .c file containing the full function. I always

After updating my POD install, Xcode sprouted a new issue: blackops Make sure you open the .xcworkspace file rather than the project file ( .xcodeproj ) when working with pods. That should solve the issue with linking. Some times you need just clean build. It helped me. To clean build go Product -> Clean There are several cases that cause this issue. At the moment, this question has no any accepted answer and also I found another solution for the same issue, I am posting my answer/experience here. In you application, go to Target -> Build Settings, then you will find following attributes.

Sorry I know this has been covered all over the place, only I can't fix this to save my life. If someone could explain clearly what I might have done and what I might be able to do to fix this I would be forever grateful. Here is my error: Command /Xcode 4/Platforms/iPhoneOS.platform/Developer/usr/bin/llvm-gcc-4.2 failed with exit code 1 ld: duplicate symbol _OBJC_IVAR_$_sunnyHillsTL._tileMap in /Users/kahanejosh/Library/Developer/Xcode/DerivedData/workingTitle-cawhuhbkmwcesmbqxvkbkbatdbze/Build/Products/Debug-iphoneos/libcocos2d libraries.a(sunnyHillsTL.o) and /Users/kahanejosh/Library

I have static libraries A, B and C organized into Xcode projects. A and B depend on C. When I build an iPhone project that depends on A and B, I get a linker error that a duplicate symbol (from C) was detected in A and B. How can I organize these three static libraries so I can include them in other Xcode projects without experiencing this error? jamie Carl's answer is right, but for the wrong reasons: there's actually nothing wrong with linking static libraries together, as we can see using Carl's own sample. Set-up Carl's sample code and then do this: (I use libtool because that is what