Explanation

This app demonstrates an issue when trying to use the OLMKit pod with the use_frameworks! setting.

The use_frameworks! setting is required in order for a Swift app to use the pods (it is not required for Obj-C development, however).

Try this:

1. pod install - to install all dependencies
2. Run the project (simulator is fine). The app pulls all the public rooms from https://matrix.org.
3. un-comment the use_frameworks! setting in the podfile. pod install again.
4. Attempt to build the project. It fails! (see below)
5. comment out pod 'OLMKit' in the podfile. pod install once more.
6. Attempt to build and run the project. It works! (but encryption won't be supported... gross)

Error message

The compiler fails with a Apple Mach-O Linker Error. Here is the text:

Ld /Users/averypierce/Library/Developer/Xcode/DerivedData/Dummy-Matrix-Client-Objc-csvtfdgrguorkhbzywnmlealmfke/Build/Products/Debug-iphonesimulator/OLMKit/OLMKit.framework/OLMKit normal x86_64
cd /Users/averypierce/Projects/Junk/Dummy-Matrix-Client-Objc/Pods
export IPHONEOS_DEPLOYMENT_TARGET=8.0
export PATH="/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/usr/bin:/Applications/Xcode.app/Contents/Developer/usr/bin:/usr/local/bin:/usr/bin:/bin:/usr/sbin:/sbin"
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang++ -arch x86_64 -dynamiclib -isysroot /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator10.2.sdk -L/Users/averypierce/Library/Developer/Xcode/DerivedData/Dummy-Matrix-Client-Objc-csvtfdgrguorkhbzywnmlealmfke/Build/Products/Debug-iphonesimulator/OLMKit -F/Users/averypierce/Library/Developer/Xcode/DerivedData/Dummy-Matrix-Client-Objc-csvtfdgrguorkhbzywnmlealmfke/Build/Products/Debug-iphonesimulator/OLMKit -filelist /Users/averypierce/Library/Developer/Xcode/DerivedData/Dummy-Matrix-Client-Objc-csvtfdgrguorkhbzywnmlealmfke/Build/Intermediates/Pods.build/Debug-iphonesimulator/OLMKit.build/Objects-normal/x86_64/OLMKit.LinkFileList -install_name @rpath/OLMKit.framework/OLMKit -Xlinker -rpath -Xlinker @executable_path/Frameworks -Xlinker -rpath -Xlinker @loader_path/Frameworks -mios-simulator-version-min=8.0 -dead_strip -Xlinker -object_path_lto -Xlinker /Users/averypierce/Library/Developer/Xcode/DerivedData/Dummy-Matrix-Client-Objc-csvtfdgrguorkhbzywnmlealmfke/Build/Intermediates/Pods.build/Debug-iphonesimulator/OLMKit.build/Objects-normal/x86_64/OLMKit_lto.o -Xlinker -export_dynamic -Xlinker -no_deduplicate -Xlinker -objc_abi_version -Xlinker 2 -stdlib=libc++ -fobjc-arc -fobjc-link-runtime -lc++ -framework Foundation -single_module -compatibility_version 1 -current_version 1 -Xlinker -dependency_info -Xlinker /Users/averypierce/Library/Developer/Xcode/DerivedData/Dummy-Matrix-Client-Objc-csvtfdgrguorkhbzywnmlealmfke/Build/Intermediates/Pods.build/Debug-iphonesimulator/OLMKit.build/Objects-normal/x86_64/OLMKit_dependency_info.dat -o /Users/averypierce/Library/Developer/Xcode/DerivedData/Dummy-Matrix-Client-Objc-csvtfdgrguorkhbzywnmlealmfke/Build/Products/Debug-iphonesimulator/OLMKit/OLMKit.framework/OLMKit

duplicate symbol _OLMKitVersionString in:
    /Users/averypierce/Library/Developer/Xcode/DerivedData/Dummy-Matrix-Client-Objc-csvtfdgrguorkhbzywnmlealmfke/Build/Intermediates/Pods.build/Debug-iphonesimulator/OLMKit.build/Objects-normal/x86_64/OLMKit.o
    /Users/averypierce/Library/Developer/Xcode/DerivedData/Dummy-Matrix-Client-Objc-csvtfdgrguorkhbzywnmlealmfke/Build/Intermediates/Pods.build/Debug-iphonesimulator/OLMKit.build/Objects-normal/x86_64/OLMKit_vers.o
ld: 1 duplicate symbol for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)