Compiling iOS library with bitcode enabled

Question

I need to release a framework with bitcode enabled which turns out as a hassle. I set 'Enable Bitcode' in the project's settings to 'YES' and it builds cleanly for both a real device and a simulator.

I wanted to test the library so I integrated it to a new app I created for this purpose but now it only build for simulators. When I try to build for a real device I get:

ld: '/path/to/Framework.framework/Company(File.o)' does not contain bitcode. You must rebuild it with bitcode enabled (Xcode setting ENABLE_BITCODE), obtain an updated library from the vendor, or disable bitcode for this target. for architecture armv7
clang: error: linker command failed with exit code 1 (use -v to see invocation)

Like I said, I had built it with Bitcode enabled so I'm not sure why this happens.

Any ideas? thanks

Answer 1

AFAIK, when you build app with Xcode it includes Bitcode only when you make archive, the reason - decrease compile time when just want to debug or test the app/library.

To ensure that Xcode emits bitcode at each build you can add -fembed-bitcode flag to Other C flags and Other linker flags:

Also, the easiest way to check if the binary contains bitcode is to use otool and grep:

otool -l binary_name | grep __LLVM

you will see one or more segname __LLVM entries if it does have bitcode or empty output if does not.

Answer 2

Another way with RunScript code: (build setting -- Build Phases RunScript)

# define output folder environment variable
UNIVERSAL_OUTPUTFOLDER=${BUILD_DIR}/${CONFIGURATION}-universal

# Step 1. Build Device and Simulator versions
xcodebuild -target TARGETNAME ONLY_ACTIVE_ARCH=NO -configuration Release -sdk iphoneos  BUILD_DIR="${BUILD_DIR}" BUILD_ROOT="${BUILD_ROOT}"
xcodebuild -target TARGETNAME -configuration Release -sdk iphonesimulator BUILD_DIR="${BUILD_DIR}" BUILD_ROOT="${BUILD_ROOT}"

# make sure the output directory exists
mkdir -p "${UNIVERSAL_OUTPUTFOLDER}"

# Step 2. Create universal binary file using lipo
lipo -create -output "${UNIVERSAL_OUTPUTFOLDER}/lib${PROJECT_NAME}.a" "${BUILD_DIR}/${CONFIGURATION}-iphoneos/lib${PROJECT_NAME}.a" "${BUILD_DIR}/${CONFIGURATION}-iphonesimulator/lib${PROJECT_NAME}.a"

# Last touch. copy the header files. Just for convenience
cp -R "${BUILD_DIR}/${CONFIGURATION}-iphoneos/include" "${UNIVERSAL_OUTPUTFOLDER}/"

Answer 3

For enabling bitcode using xcodebuild command you have to add

BITCODE_GENERATION_MODE=bitcode.

find the below command

xcodebuild BITCODE_GENERATION_MODE=bitcode -target TARGETNAME ONLY_ACTIVE_ARCH=NO -configuration Release -sdk iphoneos  BUILD_DIR="${BUILD_DIR}" BUILD_ROOT="${BUILD_ROOT}"